JP2005193743A - Vehicle tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To bury a passive type radio tag in a tire, and to simultaneously send a tire ID memorized in the radio tag to an exterior device beyond a communication range of the radio tag with air pressure data. <P>SOLUTION: A pressure monitoring unit 4 is attached to a tire inner space 11 side of an air valve 3. In the inside 12 of a structure member of the tire 1, the radio tag 5 is buried. When a radio communication device (not shown) on the outside accesses to the pressure monitoring unit 4, the pressure monitoring unit 4 detects air pressure of the tire inner space 11, and accesses to the radio tag 5. The radio tag 5 operates by using electric power of an access signal of the pressure monitoring unit 4 as a poser source, and sends the tire ID memorized in advance to the pressure monitoring unit 4. The pressure monitoring unit 4 simultaneously sends the received tire ID, and the detected air pressure data to the radio communication device on the outside. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle tire that can simultaneously read air pressure data and a tire ID by wireless communication from the outside.

  It is known to detect the air pressure of an automobile tire and notify a driver or the like of an abnormality in the air pressure. For example, Patent Literature 1 discloses a tire internal pressure detection device configured to wirelessly transmit an output of an air pressure sensor attached to a tire rim to a receiving unit attached to a vehicle body side brake cover. . The tire internal pressure detecting device radiates electromagnetic waves from the antenna coil of the receiving unit toward the air pressure sensor, receives an echo signal from the air pressure sensor, and detects an abnormal internal pressure of the tire based on a frequency change of the echo signal.

There is also known a system in which an electronic device having an ID (identification code) of a tire is embedded in a tire of an automobile so that the ID can be read from outside without contact. For example, Patent Document 2 discloses an RFID system in which an RFID tag (Radio Frequency IDentification tag: hereinafter referred to as a wireless tag) is embedded in a tire and wireless communication is performed with an external RFID interrogator. Yes.
Japanese Patent Application Laid-Open No. 8-219922 JP 7-321698 A

  However, the tire internal pressure detection device described in Patent Document 1 can read tire pressure data in a non-contact manner, but cannot read the tire ID. For example, when the tire is punctured, the cause is investigated. It is difficult to follow up. On the other hand, in the RFID system described in Patent Document 2, the tire pressure data cannot be read even though the tire ID can be read in a non-contact manner.

  In addition, the wireless tag embedded in the tire needs to be ultra-small, and for that purpose, a passive type without a battery is desirable. However, in the case of the passive type, the power required for operation is obtained by rectifying the radiated electromagnetic field of an external RFID interrogator, so the communication distance is short compared to an active type wireless tag with a built-in battery. There is a drawback. Furthermore, when this passive wireless tag is embedded in a tire, the communication distance is drastically reduced due to the influence of rubber and other components. According to our experimental results, when a passive wireless tag having a communication distance of 30 cm in free space was embedded in the tire, the communication distance was reduced to a maximum of 5 cm even if various conditions were optimized.

  On the other hand, there is a tire pressure monitoring system (TPMS) currently available on the market. Since TPMS has a built-in battery and a communication distance is about 1 to 5 m, there is no problem in the communication distance.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a vehicle tire that can simultaneously read tire pressure data and ID without contact.

  The present invention also provides a vehicle tire in which a passive wireless tag is embedded in a tire, and a tire ID stored in the wireless tag can be simultaneously transmitted to an external device beyond the communication distance of the wireless tag together with tire air pressure data. And a wireless system built in the tire.

  The invention according to claim 1 is an air pressure monitoring unit having a function of detecting tire air pressure and a function of transmitting the detected air pressure data wirelessly, a function of storing a tire ID, and transmitting the tire ID wirelessly. The vehicle tire is characterized in that the tire ID and the air pressure data are simultaneously transmitted in response to an access from an external wireless communication device. With this configuration, when accessed from an external wireless communication device, the air pressure data detected by the air pressure monitoring unit and the tire ID stored in the wireless tag can be simultaneously transmitted to the external wireless communication device. it can.

  According to a second aspect of the present invention, in the vehicle tire according to the first aspect, the wireless tag is embedded in the tire. With this configuration, since the wireless tag is surrounded and held by the tire components, there is a risk of peeling due to poor adhesion compared to the case where the wireless tag is fixed to the inner wall surface of the tire with an adhesive or the like. Therefore, it can be operated in a stable state at all times.

  According to a third aspect of the present invention, in the vehicle tire according to the first aspect, the air pressure monitoring unit is attached to the inside of the tire of the air valve of the wheel. With this configuration, the air pressure monitoring unit can be easily attached and detached.

  According to a fourth aspect of the present invention, in the vehicle tire according to the first aspect, the wireless tag does not have a built-in power supply for operation, and obtains power for operation from the received electromagnetic field. It is. With this configuration, the wireless tag can acquire operating power from an electromagnetic field radiated from an external wireless communication device or an electromagnetic field radiated from an air pressure monitoring unit.

  According to a fifth aspect of the present invention, in the vehicle tire according to the first aspect, the air pressure monitoring unit includes an operation power source and radiates an electromagnetic field for the operation power to the wireless tag. It is characterized by. With this configuration, the air pressure monitoring unit can supply power to a wireless tag that does not incorporate an operation power supply.

  According to a sixth aspect of the present invention, in the vehicle tire according to the first aspect, the wireless tag transmits a tire ID to the air pressure monitoring unit, the air pressure monitoring unit receives the tire ID, and an air pressure The data is transmitted to an external wireless communication apparatus together with the data. With this configuration, the air pressure monitoring unit can simultaneously transmit the tire ID received from the wireless tag and the air pressure data detected by itself to an external wireless communication device.

  According to a seventh aspect of the present invention, in the vehicle tire according to the first aspect, the air pressure monitoring unit and the wireless tag can individually perform wireless communication with an external wireless communication device. Is. With this configuration, the air pressure monitoring unit and the wireless tag can individually transmit the air pressure data or the tire ID for access from an external wireless communication device.

  The invention according to claim 8 is a pneumatic pressure monitoring unit having a function of detecting tire air pressure and a function of transmitting the detected air pressure data wirelessly, a function of storing tire ID, and transmitting the tire ID wirelessly. A wireless system that simultaneously transmits the tire ID and the air pressure data in response to a data transmission request from an external wireless communication device, wherein the air pressure monitoring unit wirelessly transmits the data to the wireless tag. Thus, it is possible to supply power, and the tire ID can be transmitted wirelessly from the wireless tag to the air pressure monitoring unit. With this configuration, for access from an external wireless communication device, the air pressure monitoring unit supplies power to a wireless tag that does not incorporate an operation power supply, and the wireless tag transmits a tire ID to the air pressure monitoring unit. The air pressure monitoring unit can simultaneously transmit the tire ID received from the wireless tag and the air pressure data detected by itself to an external wireless communication device.

  According to the vehicle tire of the present invention, the air pressure monitoring unit having the function of detecting the tire air pressure and the function of transmitting the detected air pressure data wirelessly, the function of storing the tire ID, and the tire ID wirelessly. And the tire ID and the air pressure data are simultaneously transmitted in response to a data transmission request from an external wireless communication device, so that the air pressure data and the tire ID are transmitted from the external wireless communication device. Can be read simultaneously without contact.

  Further, according to the vehicle tire according to the present invention, since the wireless tag does not include the operation power supply and acquires the operation power from the received electromagnetic field, the tire ID can be obtained even when the passive wireless tag is used. Can be read simultaneously with the air pressure data from an external wireless communication device without contact.

  Further, according to the vehicle tire according to the present invention, the wireless tag transmits a tire ID to the air pressure monitoring unit, and the air pressure monitoring unit receives the tire ID, and an external wireless communication device together with the air pressure data. Therefore, even if a passive wireless tag with a short communication distance is used, the tire ID can be read out in a non-contact manner simultaneously with the air pressure data from an external device beyond the communication distance of the wireless tag.

  FIG. 1 is a diagram showing a configuration of a tire according to an embodiment of the present invention. In this figure, (a) is a horizontal sectional view of a tire. Further, (b) is a side view corresponding to the configuration of (a), (c) is a side view when the positional relationship between the air pressure monitoring unit 4 and the wireless tag 5 is different from (a) and (b). It is. For convenience, (b) and (c) are shown in 1/2 size of (a). 2 is a block diagram showing an electrical configuration of the air pressure monitoring unit 4 and the wireless tag 5 in FIG. 1, and FIG. 3 is a sequence diagram showing an operation of reading air pressure data and a tire ID from the tire of FIG.

  As shown in FIG. 1A, the tire 1 is mounted on the rim 21 of the wheel 2, and an internal space 11 of the tire 1 is formed inside the tire 1 and the rim 21. An air valve 3 for supplying air to the internal space 11 of the tire 1 is attached to the rim 21. The above is the same as the structure of a general tire. In the present embodiment, the air pressure monitoring unit 4 is fixed to the tire internal space 11 side of the air valve 3. A wireless tag 5 is embedded in the interior 12 of the constituent member of the tire 1. As will be described later, since the air pressure monitoring unit 4 performs wireless communication with the wireless tag 5, it is necessary to arrange the air pressure monitoring unit 4 in a positional relationship that allows mutual communication. 1 (b) and 1 (c) are naturally arranged in such a positional relationship, but as shown in FIG. 1 (c), the same radius of the tire 1 when viewed from the side of the tire 1 is used. When arranged in the direction, the mutual distance is the shortest, so it can be said that it is best to arrange in the positional relationship.

  As shown in FIG. 2A, the air pressure monitoring unit 4 includes a control unit 41, a detection unit 42, a storage unit 43, a transmission / reception unit 44, and a battery 45, each of which is connected to the control unit 41. It has. An antenna 46 is connected to the transmission / reception unit 44. The control unit 41 controls the entire air pressure monitoring unit 4 and the like. The detection unit 42 detects the air pressure in the internal space 11 of the tire 1. The storage unit 43 stores various programs necessary for the operation of the control unit 41 in advance. In addition, data such as air pressure data detected by the detection unit 42 and tire ID received from the wireless tag 5 is stored. The transmission / reception unit 44 performs wireless communication with an external wireless communication device (not shown) and the wireless tag 5. The antenna 46 emits and receives an electromagnetic field during wireless communication. The battery 45 supplies power for operation to each part. The air pressure monitoring unit 4 includes a battery, and the communication distance is sufficiently longer than the communication distance of the passive wireless tag 5 that does not include the battery.

  As shown in FIG. 2B, the wireless tag 5 includes a control unit 51, a storage unit 52 that is connected to the control unit 51, and a transmission / reception unit 53. An antenna 54 is connected to the transmission / reception unit 53. The controller 51 controls the entire wireless tag 5 and the like. Various programs necessary for the operation of the control unit 51 and the tire ID of the tire 1 are stored in the storage unit 52 in advance. The transmission / reception unit 53 performs wireless communication with the air pressure monitoring unit 4. The antenna 54 emits and receives an electromagnetic field during wireless communication. In addition, the transmission / reception unit 53 rectifies and holds the electromagnetic wave carrier wave received by the antenna 54, and supplies the operation power to the control unit 51 and the storage unit 52 as well as operation power for the transmission / reception unit 53 itself. .

  Next, an operation for reading the air pressure data and the tire ID from the external wireless communication device for the tire 1 configured as described above will be described. An external wireless communication device (not shown) is disposed at a position where wireless communication with the air pressure monitoring unit 4 in FIG. 1 is possible, and transmits an access signal to the air pressure monitoring unit 4 (step S1 in FIG. 3). In the air pressure monitoring unit 4, the transmission / reception unit 44 receives an access signal through the antenna 46 and sends it to the control unit 41. When receiving the access signal, the control unit 41 controls the detection unit 42 to measure the air pressure data and controls the transmission / reception unit 44 to send the access signal to the wireless tag 5 (procedure of FIG. 3). S2). The air pressure data measured by the detection unit 42 is stored in the storage unit 43. In the wireless tag 5, the electromagnetic field of the access signal from the air pressure monitoring unit 4 is received by the antenna 54, rectified and held by the transmission / reception unit 53, and becomes the operation power of the transmission / reception unit 53 itself. The electric power for operation is supplied to the unit 52. The access signal from the air pressure monitoring unit 4 is received by the transmission / reception unit 53 through the antenna 54 and sent to the control unit 51. When receiving the access signal, the control unit 51 reads the tire ID stored in the storage unit 52 and transmits the tire ID to the air pressure monitoring unit 4 via the transmission / reception unit 53 and the antenna 54 (step S3 in FIG. 3). In the air pressure monitoring unit 4, the tire ID is received by the transmission / reception unit 44 through the antenna 46 and sent to the control unit 41. The control unit 41 temporarily stores the tire ID in the storage unit 43, then reads the tire ID together with the air pressure data, and transmits the tire ID to the external wireless communication device via the transmission / reception unit 44 and the antenna 46 (step S4 in FIG. 3). In this way, the external wireless communication apparatus reads the tire pressure data and the tire ID at the same time.

Thus, this embodiment has the following characteristics.
(1) Air pressure data and tire ID can be simultaneously transmitted to an external wireless communication device.
(2) Since the wireless tag 5 employs a small and light passive wireless tag, the wireless tag 5 can be easily embedded in the interior 12 of the constituent member of the tire 1. Then, by embedding in the inside 12 of the constituent member of the tire 1, there is no fear of peeling as compared with the case where it is fixed to the inner wall surface of the constituent member of the tire 1, so that it can always be operated in a stable state.
(3) The wireless tag 5 and the external wireless communication device do not directly perform wireless communication, but perform wireless communication with the external wireless communication device via the air pressure monitoring unit 4 having a sufficiently longer communication distance than the wireless tag 5. Therefore, even if the external wireless communication device is disposed outside the communication distance of the wireless tag 5 alone, the tire ID can be read out within the communication distance of the air pressure monitoring unit 4. As a result, the communication distance between the wireless tag 5 and the external wireless communication device can be greatly increased as compared with the case of the wireless tag 5 alone.
(4) The air pressure monitoring unit 4 can be easily attached and detached.
According to the experiment by the present inventor, a passive wireless tag having a communication distance of 70 cm in a free space is attached inside a 195/65 R15 tire, a wheel is attached, and a radio wave transmission source is provided outside the tire. As a virtual air pressure monitoring unit, a communication experiment was conducted, and the communication distance was 50 cm. Accordingly, if the wireless tag 5 and the air pressure monitoring unit 4 are arranged in the positional relationship of FIG. 1C, the wireless tag 5 and the air pressure monitoring unit 4 can communicate with each other regardless of the tire. I was able to confirm.

  In addition, this invention is not limited to the said embodiment, For example, various deformation | transformation like following (1)-(4) are possible.

(1) The wireless tag 5 is an active type that has a built-in battery.
(2) The air pressure monitoring unit 4 is a passive type that does not incorporate a battery.
(3) The wireless tag 5 and the air pressure monitoring unit 4 are configured to be able to transmit data individually and simultaneously for access from an external wireless communication device.
(4) The wireless tag 5 is not embedded in the inside 12 of the constituent member of the tire 1 but is fixed to the inner wall surface of the constituent member.

It is a figure which shows the structure of the tire which is embodiment of this invention. It is a block diagram which shows the electrical structure of the air pressure monitoring unit in FIG. 1, and a wireless tag. It is a sequence diagram which shows the operation | movement which reads air pressure data and tire ID from the tire of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Tire, 2 ... Wheel, 3 ... Air valve, 4 ... Air pressure monitoring unit, 5 ... Wireless tag.

Claims (8)

  An air pressure monitoring unit having a function of detecting tire air pressure and a function of wirelessly transmitting the detected air pressure data, and a wireless tag having a function of storing a tire ID and a function of wirelessly transmitting the tire ID And the tire ID and the air pressure data are simultaneously transmitted in response to an access from an external wireless communication device.   The vehicle tire according to claim 1, wherein the wireless tag is embedded in the tire.   The vehicle tire according to claim 1, wherein the air pressure monitoring unit is attached to an inside of a tire of a pneumatic valve of a wheel.   2. The vehicle tire according to claim 1, wherein the wireless tag does not include a power source for operation and acquires power for operation from the received electromagnetic field. 3.   5. The vehicle tire according to claim 4, wherein the air pressure monitoring unit includes an operation power source and radiates an electromagnetic field for operation power to the wireless tag.   The wireless tag transmits the tire ID to the air pressure monitoring unit, and the air pressure monitoring unit receives the tire ID and transmits the tire ID together with the air pressure data to an external wireless communication device. The vehicle tire described.   2. The vehicle tire according to claim 1, wherein the air pressure monitoring unit and the wireless tag are individually capable of wireless communication with an external wireless communication device.   An air pressure monitoring unit having a function of detecting tire air pressure and a function of transmitting the detected air pressure data wirelessly, and a wireless tag having a function of storing tire ID and a function of transmitting the tire ID wirelessly A wireless system for simultaneously transmitting the tire ID and the air pressure data in response to an access from an external wireless communication device, wherein power can be wirelessly supplied from the air pressure monitoring unit to the wireless tag; A wireless system capable of transmitting a tire ID wirelessly from a tag to the air pressure monitoring unit.

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