JP6568824B2 - Tire condition detection device - Google Patents

Description

  The present invention relates to a tire condition detection device.

  For example, Patent Document 1 discloses a tire state monitoring device provided in a vehicle including a plurality of wheels. The tire condition monitoring device described in Patent Literature 1 includes a tire condition detection device mounted on a wheel and a receiver.

  The tire condition detection device includes a condition detection unit that detects the condition of the tire, and a transmission unit that transmits a transmission signal including information indicating the tire condition detected by the condition detection unit. Further, individual identification information is set in the tire state detection device. This identification information is also included in the transmission signal. The receiver includes a receiving unit that receives a transmission signal and a receiver control unit.

  A transmission signal corresponding to the protocol of the receiver is transmitted from the transmission unit. When the receiving unit receives a transmission signal corresponding to the protocol corresponding to the receiver, the receiver control unit determines from the identification information included in the transmission signal whether the transmission signal is a transmission signal transmitted to itself. Process to do. When it is determined that the transmission signal is a transmission signal transmitted to itself, the receiver control unit acquires information indicating the state of the tire included in the transmission signal.

JP 2014-91344 A

  By the way, the protocol of the receiver differs depending on the manufacturer that manufactures the receiver. When manufacturing a tire condition detection device corresponding to the protocol of each receiver, the number of tire condition detection devices corresponding to the type of protocol is required. Therefore, a tire condition detection apparatus corresponding to a multi-protocol has been proposed as a tire condition detection apparatus. The tire condition detection device corresponding to the multi-protocol transmits transmission signals corresponding to a plurality of types of protocols. That is, the tire condition detection device corresponding to the multi-protocol also transmits a transmission signal according to a protocol different from the protocol corresponding to the receiver mounted on the vehicle on which the tire is detected. Then, the transmission signal transmitted from the tire condition detection device may be received by a receiver mounted on another vehicle.

  An object of the present invention is to provide a tire state detection device capable of suppressing a receiver mounted on another vehicle from processing data included in a transmission signal.

  A tire condition detection device that solves the above problem includes a receiving unit that receives a transmission signal and a control unit for a receiver that acquires data included in the transmission signal, and transmits the transmission to a receiver mounted on a vehicle. A tire condition detection device that transmits a signal, a condition detection unit that detects a condition of a tire mounted on a wheel, a storage unit that stores a plurality of types of protocols, and the tire that is detected by the condition detection unit A transmission unit that transmits a transmission signal including the state of the control unit, and a control unit that causes the transmission unit to transmit a transmission signal. Among the plurality of types of protocols, the protocol corresponding to the receiver is a first protocol, If the second protocol is a protocol different from the protocol corresponding to the receiver, the control unit is configured to use a frame format defined by the first protocol. DOO transmission signal, and to transmit the frame format transmitted signal which mislead the synchronous bit in the frame format defined by the second protocol to the transmitting unit.

  When the synchronization bit is correct in the frame format defined by the protocol, the receiver control unit of the receiver acquires data included in the received transmission signal. Since the transmission signal transmitted from the transmission unit is transmitted in the frame format defined by the first protocol, the receiver control unit corresponding to the first protocol transmits the data included in the transmission signal. get. That is, the receiver control unit of the receiver mounted on the vehicle provided with the above-described tire condition detection device acquires data included in the transmission signal.

  On the other hand, the data included in the transmission signal of the frame format in which the synchronization bit in the frame format defined by the second protocol is mistaken is acquired by the receiver control unit of the receiver corresponding to the second protocol. Not. For this reason, when there is another vehicle equipped with a receiver corresponding to the second protocol around the vehicle provided with the above-described tire condition detection device, for the receiver of the receiver mounted on the vehicle. The control unit does not acquire data included in the transmission signal. Therefore, the tire state detection device can suppress the receiver included in the other vehicle from processing the data included in the transmission signal.

  A tire condition detection device that solves the above problem includes a receiving unit that receives a transmission signal and a control unit for a receiver that acquires data included in the transmission signal, and transmits the transmission to a receiver mounted on a vehicle. A tire condition detection device that transmits a signal, a condition detection unit that detects a condition of a tire mounted on a wheel, a storage unit that stores a plurality of types of protocols, and the tire that is detected by the condition detection unit A transmission unit that transmits a transmission signal including the state of the control unit, and a control unit that causes the transmission unit to transmit a transmission signal. Among the plurality of types of protocols, the protocol corresponding to the receiver is a first protocol, If the second protocol is a protocol different from the protocol corresponding to the receiver, the control unit is configured to use a frame format defined by the first protocol. DOO transmission signal, and to transmit the frame format transmitted signal which mislead an error detection or correction code in the frame format defined by the second protocol to the transmitting unit.

  The receiver control unit of the receiver, when the synchronization bit is correct among the frame formats defined by the protocol, and the code present in the frame format among the error detection code and error correction code is correct, Data included in the transmission signal is acquired. For this reason, the receiver control unit of the receiver corresponding to the second protocol does not acquire data included in the transmission signal of the frame format in which the error detection code or the error correction code is erroneously set. Therefore, the tire state detection device can suppress the receiver included in the other vehicle from processing the data included in the transmission signal.

  A tire condition detection device that solves the above problem includes a receiving unit that receives a transmission signal and a control unit for a receiver that acquires data included in the transmission signal, and transmits the transmission to a receiver mounted on a vehicle. A tire condition detection device that transmits a signal, a condition detection unit that detects a condition of a tire mounted on a wheel, a storage unit that stores a plurality of types of protocols, and the tire that is detected by the condition detection unit A transmission unit that transmits a transmission signal including the state of the control unit, and a control unit that causes the transmission unit to transmit a transmission signal. Among the plurality of types of protocols, the protocol corresponding to the receiver is a first protocol, If the second protocol is a protocol different from the protocol corresponding to the receiver, the control unit is configured to use a frame format defined by the first protocol. A transmission signal having a frame format defined by a second protocol is transmitted at a first transmission rate at which the receiver can acquire data included in the transmission signal. The transmission is performed at a second transmission rate that is higher than the second transmission rate.

  In the receiver, a transmission rate at which data included in the transmission signal can be acquired is set. When the receiving unit receives a transmission signal transmitted at a transmission rate higher than the transmission rate, the receiver control unit does not acquire data included in the transmission signal. Therefore, the data included in the transmission signal of the frame format defined by the second protocol is less likely to be acquired by the receiver control unit than the data included in the transmission signal of the frame format defined by the first protocol. . For this reason, it is suppressed that the receiver control unit of the receiver corresponding to the second protocol acquires the data of the transmission signal. Therefore, the tire state detection device can suppress the receiver included in the other vehicle from processing the data included in the transmission signal.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress making the receiver mounted in the other vehicle process the data contained in a transmission signal.

Schematic of a vehicle equipped with a receiver corresponding to the first protocol, a vehicle equipped with a receiver compatible with the second protocol, and a trigger device. The schematic block diagram of a transmitter and a trigger device. (A) is a schematic diagram showing a frame format defined by protocol A, (b) is a schematic diagram showing a frame format defined by protocol B. Schematic which shows the frame format which made the synchronization bit mislead. Schematic of consolidated data. Schematic which shows the frame format which made the CRC code mislead. Schematic which shows the speed | rate which transmits the transmission signal of the frame format defined by each protocol.

(First embodiment)
Hereinafter, the tire state detection device of the first embodiment will be described.
As shown in FIG. 1, the tire condition monitoring device 20 includes a transmitter 21 that is attached to each of the four wheels 11 of the vehicle 10, and a receiver 40 that is installed on the vehicle body of the vehicle 10. Each wheel 11 includes a wheel 12 and a tire 13 attached to the wheel 12.

First, the transmitter 21 will be described.
The transmitter 21 is attached to the wheel 11 so as to be disposed in the internal space of the tire 13. The transmitter 21 as a tire condition detection device detects the condition of the corresponding tire 13 (for example, tire pressure or tire internal temperature), and wirelessly transmits a transmission signal including information on the detected tire 13 to the receiver 40. . The tire condition monitoring device 20 is a device that monitors the condition of the tire 13 by receiving a transmission signal transmitted from the transmitter 21 by the receiver 40.

  As shown in FIG. 2, the transmitter 21 includes a pressure sensor 22, a temperature sensor 23, an acceleration sensor 24, a control unit 25, a transmission circuit 26, a reception circuit 27, a transmission antenna 28, a reception antenna 29, and a battery 30. . The battery 30 is a power source for the transmitter 21.

  The pressure sensor 22 as a state detection unit detects the air pressure of the corresponding tire 13. The pressure sensor 22 outputs the detection result to the control unit 25. The temperature sensor 23 as a state detection unit detects the temperature in the corresponding tire 13. The temperature sensor 23 outputs the detection result to the control unit 25. The acceleration sensor 24 rotates with the wheel 11 and detects the acceleration acting on itself. The acceleration sensor 24 outputs the detection result to the control unit 25.

  The control unit 25 includes a microcomputer including a CPU 25a and a storage unit 25b (RAM, ROM, etc.). An ID code which is identification information unique to each transmitter 21 is registered in the storage unit 25b. In addition, a plurality of types of protocols are stored in the storage unit 25b. As the plurality of types of protocols, protocols corresponding to vehicle receivers on which the transmitter 21 can be mounted are stored. The transmitter 21 of the present embodiment is a multi-protocol transmitter that allows a plurality of receivers to receive data. In the present embodiment, three protocols are stored in the storage unit 25b. In the following description, the three protocols are indicated as protocol A, protocol B, and protocol C, respectively.

  In the protocol, a plurality of frames are defined. There are frames used for data transmission in the plurality of frames. The format of this frame (frame format) differs for each protocol.

  As shown in FIG. 3A, the frame format F1 of protocol A includes a synchronization bit area A1, an identification information area A2, a status area A3, a pressure area A4, a temperature area A5, and an error detection area A6. . A synchronization bit corresponding to the protocol is stored in the synchronization bit area A1. An ID code corresponding to the transmitter 21 is stored in the identification information area A2. Data indicating the state of the transmitter 21 is stored in the status area A3. The air pressure data of the tire 13 is stored in the pressure region A4. The temperature data of the tire 13 is stored in the temperature region A5. An error detection code is stored in the error detection area A6. In the present embodiment, a CRC code used for CRC (Cyclic Redundancy Check) is stored in the error detection area A6 as an error detection code.

  As shown in FIG. 3B, the frame format F2 of protocol B includes the same areas A1 to A6 as the frame format F1 of protocol A. In the protocol B, the order of the pressure region A4 and the temperature region A5 is opposite to the protocol A. Although not shown, the frame format of protocol C is different from protocols A and B. For example, the size (bit) of each region is different, or a region for storing acceleration data is included.

  The control unit 25 synchronizes the frame format data defined by the first protocol corresponding to the receiver 40 and the frame format defined by the second protocol different from the protocol corresponding to the receiver 40. Generate frame format data with incorrect bits. The transmitter 21 has a synchronization bit (correct synchronization bit) for synchronizing with the receiver 40. To make the synchronization bit wrong means to generate data storing a synchronization bit different from the correct synchronization bit. For example, when the first protocol is protocol A, the control unit 25 causes the synchronization bit to be erroneous in the frame format of protocol B as shown in FIG. Similarly for protocol C, the synchronization bit in the frame format is erroneous.

  The control unit 25 concatenates the data in the frame format defined in the first protocol and the data in the frame format in which the synchronization bit in the frame format defined in the second protocol is erroneously linked into one concatenation. Data. For example, when the first protocol is the protocol A, as shown in FIG. 5, the frame format data defined in the protocol A (protocol A in the figure), and the synchronization bits out of the frame formats of the protocols B and C are mistaken. The frame format data (protocols B ′ and C ′ in the figure) are concatenated into one concatenated data.

  The control unit 25 outputs data obtained by adding the master CRC code to the concatenated data to a transmission circuit 26 as a transmission unit. The master CRC code is an error detection code for concatenated data. The transmission circuit 26 modulates the output data to generate a transmission signal (RF signal), and transmits the transmission signal via the transmission antenna 28. As a result, the transmission signal of the frame format defined by the first protocol and the transmission signal of the frame format in which the synchronization bit is wrong among the frame formats defined by the second protocol are transmitted from the transmission circuit 26. .

The reception circuit 27 receives a trigger signal transmitted from a trigger device described later via the reception antenna 29. The receiving circuit 27 demodulates the trigger signal and outputs it to the control unit 25.
Next, the receiver 40 will be described.

  As shown in FIG. 1, the receiver 40 includes a receiver control unit 41, a receiver reception circuit (reception IC) 42, and a reception antenna 43. An alarm device 44 is connected to the receiver control unit 41. A control device (vehicle ECU) 45 mounted on the vehicle 10 is connected to the receiver control unit 41.

  The receiver control unit 41 includes a microcomputer including a receiver CPU 41a and a receiver storage unit 41b (ROM, RAM, etc.). The receiver storage unit 41b stores a program and protocol for comprehensively controlling the operation of the receiver 40. The receiver receiving circuit 42 as a receiving unit demodulates the transmission signal received from each transmitter 21 via the receiving antenna 43. When the synchronization bit and the error detection code (CRC code) included in the transmission signal are correct, the receiver reception circuit 42 causes the receiver control unit 41 to acquire demodulated data. For example, the receiver receiving circuit 42 outputs a wake-up signal to the receiver control unit 41 to cause the receiver control unit 41 to acquire data. Note that the synchronization bit and the error detection code are correct means that a synchronization bit that can be synchronized with the transmitter 21 and the receiver 40 is used, and an error in the data included in the transmission signal is used as the error detection code. It means that what can be detected is used.

  The receiver control unit 41 determines whether the ID code from the acquired data matches the ID code stored in the receiver storage unit 41b. When the ID codes match, data included in the transmission signal such as data indicating the state of the tire 13 is acquired.

  Based on this, the receiver control unit 41 grasps the state of the tire 13 (for example, the tire air pressure and the tire internal temperature). The receiver control unit 41 notifies an alarm device (notifier) 44 when an abnormality occurs in the tire 13. As the alarm device 44, for example, a device for notifying abnormality by lighting or blinking of light or a device for notifying abnormality by sound is used. The receiver control unit 41 outputs the state of the tire 13 to the control device 45.

Next, the trigger device will be described.
As shown in FIGS. 1 and 2, the trigger device 50 requests the transmitter 21 to transmit a tire condition or an ID code, or changes the transmission mode (for example, transmission interval) of the transmitter 21. Used for.

  The trigger device 50 includes a plurality of operation units 51, a trigger device transmission circuit 52, a trigger device reception circuit 53, a display unit 54, a trigger device control unit 55, a trigger device transmission antenna 56, and a trigger device reception antenna. 57. Each operation unit 51 is operated by a user. The plurality of operation units 51 include an operation unit 51 corresponding to the protocol A, an operation unit 51 corresponding to the protocol B, and an operation unit 51 corresponding to the protocol C. Further, the plurality of operation units 51 include an operation unit 51 that requests the transmitter 21 to transmit an ID code and an operation unit 51 that requests a change in transmission mode.

  The operation unit 51 is connected to the trigger device control unit 55. The trigger device control unit 55 generates data in accordance with the operation of the operation unit 51. The trigger device transmission circuit 52 transmits a trigger signal (LF signal) obtained by modulating data from the trigger device transmission antenna 56. The trigger device reception circuit 53 receives a transmission signal (RF signal) transmitted from the transmitter 21 via the trigger device reception antenna 57.

The trigger device 50 of the present embodiment can specify a protocol corresponding to the receiver 40, that is, the first protocol.
When the operation unit 51 corresponding to the protocol is operated, the trigger device 50 transmits a trigger signal designating use of the protocol corresponding to the operation unit 51. The control unit 25 sets the protocol designated by the trigger signal (the protocol corresponding to the operation unit 51) as the first protocol. For example, when the operation unit 51 corresponding to the protocol A is operated, the protocol A is designated as the first protocol.

  In addition, when the operation unit 51 corresponding to the protocol is operated, the trigger device 50 may transmit a trigger signal instructing not to use the protocol corresponding to the operation unit 51. In this case, the protocol stored in the storage unit 25b is instructed to be not used for one time. As the first protocol, one protocol not designated is designated. For example, when the operation unit 51 corresponding to the protocol B and the protocol C is operated, the protocol A is designated as the first protocol.

  Next, the operation of the transmitter 21 of this embodiment will be described together with the control performed by the control unit 25. For convenience of explanation, the vehicle 10, the transmitter 21, and the receiver 40 of the embodiment will be described as the first vehicle 10, the first transmitter 21, and the first receiver 40, respectively.

  As shown in FIG. 1, it is assumed that a second vehicle 10 </ b> A (another vehicle) different from the first vehicle 10 exists around the first vehicle 10. The second vehicle 10A is provided with a second transmitter 21A mounted on the plurality of wheels 11 and a second receiver 40A mounted on the vehicle body. The second transmitter 21A and the second receiver 40A have the same configuration as the first transmitter 21 and the first receiver 40 except that the protocols are different. The second receiver 40A corresponds to the protocol B, and the second transmitter 21A transmits a transmission signal having a frame format defined by the protocol B.

  If a transmission signal having a frame format defined by the protocols A, B, and C is transmitted from the first transmitter 21, the first receiver 40 corresponding to the protocol A receives the transmission signal. . In addition, since the transmission signal includes data in the frame format defined in the protocol B, the second receiver 40A corresponding to the protocol B also transmits the transmission signal transmitted from the first transmitter 21. There is a risk of receiving.

  When the receiver receiving circuit 42 of the second receiver 40A receives the transmission signal from the first transmitter 21, the receiver control unit 41 of the second receiver 40A uses the ID code included in the transmission signal. Is stored in the receiver storage unit 41b. Since the ID code of the first transmitter 21 does not match the ID code of the second receiver 40A, the ID code confirmation process is useless for the receiver control unit 41 of the second receiver 40A. Processing. If a transmission signal is sent from the second transmitter 21A while the ID code confirmation process is being performed, data from the second transmitter 21A to be originally acquired cannot be acquired, or data processing can be performed. There is a risk of delays. That is, the second receiver 40A is included in the transmission signal from the second transmitter 21A associated with itself by processing of the transmission signal transmitted from the first transmitter 21 unrelated to itself. There is a risk of data acquisition failure.

  In the present embodiment, the first transmitter 21 transmits a frame format transmission signal defined by the protocol A, and a frame format transmission signal in which the synchronization bit is wrong among the frame formats corresponding to the protocols B and C. Is sent.

For this reason, the receiver control unit 41 of the second receiver 40A does not acquire data included in the transmission signal from the transmitter 21, and does not perform ID code confirmation processing.
On the other hand, since the synchronization bit and CRC code of the protocol A are correct, the receiver control unit 41 of the first receiver 40 partially acquires data corresponding to the protocol A in the transmission signal.

Therefore, according to the above embodiment, the following effects can be obtained.
(1) The transmitter 21 transmits a transmission signal having a frame format defined by the first protocol and a transmission signal having a frame format in which a synchronization bit is mistaken among the frame formats defined by the second protocol. Yes. Since the synchronization bit is incorrect, even when the receiver corresponding to the second protocol receives the transmission signal, the receiver control unit of this receiver does not acquire the data included in the transmission signal. For this reason, the transmitter 21 can suppress causing a receiver mounted on another vehicle to process the transmission signal.

  (2) The transmitter 21 transmits a transmission signal having a frame format defined by the first protocol and a transmission signal having a frame format in which a synchronization bit is mistaken among the frame formats defined by the second protocol. Yes. When the transmitter 21 is inspected, it is possible to inspect whether or not the transmitter 21 operates normally by using a receiver that acquires data regardless of whether the synchronization bit is correct or incorrect.

  (3) A transmitter compatible with the multi-protocol may have the same ID code as that of other transmitters. In this case, there is a risk of causing wrong data to be acquired by a receiver mounted on another vehicle. As in this embodiment, the receiver control unit of the receiver mounted on the other vehicle does not perform the ID code confirmation process, thereby acquiring erroneous data on the receiver mounted on the other vehicle. Can be suppressed.

(Second Embodiment)
Hereinafter, the tire condition detection device of the second embodiment will be described.
The transmitter 21 as the tire condition detection device has the same configuration as the transmitter 21 of the first embodiment. The transmitter 21 of the second embodiment differs from the transmitter 21 of the first embodiment in the control performed by the control unit 25. For this reason, the control performed by the control unit 25 will be described, and other description will be omitted.

  The control unit 25 according to the present embodiment transmits a transmission signal having a frame format defined by the first protocol and a transmission signal having a frame format in which the CRC code is wrong among the frame formats defined by the second protocol. The signal is transmitted to the circuit 26.

  For example, when the first protocol is the protocol A, the control unit 25 causes the CRC code to be erroneous in the frame format F2 of the protocol B as shown in FIG. Similarly for protocol C, the CRC code in the frame format is wrong. Note that the error of the CRC code indicates that the error detection of the data included in the transmission signal cannot be performed using the CRC code.

  Also in this embodiment, as in the first embodiment, the control unit 25 erroneously uses the CRC code of the frame format data defined by the first protocol and the frame format defined by the second protocol. The frame format data is concatenated into one concatenated data. Then, data obtained by adding the master CRC code to the concatenated data is output to the transmission circuit 26, and the transmission signal is transmitted from the transmission circuit 26.

Therefore, according to the said embodiment, in addition to (3) of 1st Embodiment, the following effects can be acquired.
(4) Since the CRC code is incorrect, even when the receiver corresponding to the second protocol receives the transmission signal, the receiver control unit 41 of this receiver converts the data included in the transmission signal. Do not get. For this reason, the transmitter 21 can suppress causing a receiver mounted on another vehicle to process data.

(5) When the transmitter 21 is inspected, it is possible to inspect whether the transmitter 21 operates normally by using a receiver that acquires data regardless of whether the CRC code is correct or incorrect.
(6) By making the error detection code wrong, even if the receiver that acquires the data included in the transmission signal regardless of whether the synchronization bit is correct or not, the receiver can acquire the data even when the transmission signal is received. Is suppressed.

(Third embodiment)
Hereinafter, the tire condition detection apparatus of 3rd Embodiment is demonstrated.
The transmitter 21 as the tire condition detection device has the same configuration as the transmitter 21 of the first embodiment. The transmitter 21 of the third embodiment is different from the transmitter 21 of the first embodiment in the control performed by the control unit 25. For this reason, the control performed by the control unit 25 will be described, and other description will be omitted.

  The control unit 25 according to the present embodiment transmits a transmission signal having a frame format defined by the first protocol corresponding to the receiver 40 and a transmission signal having a frame format defined by the second protocol. That is, unlike the first and second embodiments, the synchronization bit and CRC code are correct.

  The receiver 40 is set with a transmission speed (rated value) at which data included in the transmission signal can be acquired when the transmission signal is received. Data included in the transmission signal transmitted at a higher speed than the transmission speed is not acquired by the receiver control unit 41.

  When transmitting the transmission signal, the control unit 25 causes the transmission signal of the frame format defined by the first protocol to be transmitted at the first transmission rate (bit rate). The first transmission rate is a transmission rate at which data included in the transmission signal can be acquired when the receiver 40 receives the transmission signal. The control unit 25 transmits a transmission signal having a frame format defined by the second protocol at a second transmission rate (bit rate). The second transmission rate is higher than the first transmission rate. For example, when the receiver 40 receives a transmission signal, the second transmission rate is a transmission rate that does not acquire data included in the transmission signal. When the first protocol is the protocol A, as shown in FIG. 7, the transmission signal of the frame format defined by the protocol A is transmitted at the first transmission rate, and the transmission of the frame format defined by the protocols B and C is performed. A signal is transmitted at a second transmission rate.

  Next, the operation of the transmitter 21 of this embodiment will be described. As in the first embodiment, the description will be made on the assumption that the second vehicle 10A exists around the first vehicle 10 on which the first transmitter 21 and the first receiver 40 are mounted. The second receiver 40A corresponds to the protocol B as in the first embodiment.

  As the second receiver 40A, when a transmission signal transmitted at the first transmission rate is received, the data included in the transmission signal can be acquired, and the transmission signal transmitted at the second transmission rate Assume that a receiver that cannot acquire data included in the transmission signal is used.

  When a transmission signal is transmitted from the first transmitter 21, the receiver receiving circuit 42 of the first receiver 40 receives the transmission signal. Only the portion of the transmission signal that includes data in the frame format defined by protocol A is transmitted at the first transmission rate, and the other portion is transmitted at the second transmission rate. The receiver control unit 41 partially acquires data in the frame format defined by the protocol A among the data included in the transmission signal. On the other hand, since the transmission signal of the frame format defined by the protocols B and C is transmitted at the second transmission rate, the receiver control unit 41 of the second receiver 40A is defined by the protocols B and C. Data in the specified format cannot be obtained. That is, the data included in the transmission signal is acquired except when the second receiver 40A can acquire data included in the transmission signal transmitted at the second transmission speed, such as a receiver corresponding to the high-speed bit rate. I can't get it. For this reason, it is suppressed that the 2nd receiver 40A acquires the data contained in a transmission signal.

Therefore, according to the above embodiment, according to the above embodiment, the following effect can be obtained in addition to (3) of the first embodiment.
(7) The transmitter 21 transmits the transmission signal of the frame format defined by the first protocol corresponding to the receiver 40 at the first transmission rate, and the transmission signal of the frame format defined by the second protocol. At the second transmission rate. The second transmission rate is higher than the first transmission rate. For this reason, when the receiver corresponding to the second protocol cannot acquire the data included in the transmission signal transmitted at the second transmission rate, the transmission signal is not processed. Therefore, the transmitter 21 can suppress a receiver mounted on another vehicle from processing data.

(8) When inspecting the transmitter 21, it is possible to inspect whether or not the transmitter 21 operates normally by using a receiver capable of receiving a transmission signal transmitted at the second transmission rate. .
In addition, you may change embodiment as follows.

  -You may combine the control which the control part 25 of 1st Embodiment performs, and the control which the control part 25 of 2nd Embodiment performs. Specifically, the control unit 25 transmits a frame format in which a synchronization bit and a CRC code are misplaced among a transmission signal having a frame format defined by the first protocol and a frame format defined by the second protocol. May be transmitted to the transmission circuit 26.

  In each embodiment, the transmission data may be transmitted by dividing the concatenated data into a plurality of pieces. That is, the concatenated data may be transmitted as a single transmission signal, or may be transmitted as a transmission signal divided into a plurality of times.

  In the first embodiment, the control unit 25 concatenates the data in the frame format defined in the first protocol and the data in which the synchronization bit is erroneous in the frame format defined in the second protocol. However, the present invention is not limited to this. The control unit 25 individually generates data in the frame format defined by the first protocol and data in which the synchronization bit is erroneous in the frame format defined in the second protocol, and modulates each data. The transmitted signal may be transmitted from the transmission circuit 26. Similarly, in the second embodiment, the control unit 25 obtains data in the frame format defined in the first protocol and data in which the CRC code is misplaced in the frame format defined in the second protocol. A transmission signal generated individually and modulated for each data may be transmitted from the transmission circuit 26.

  In the third embodiment, the data in the frame format defined in each protocol and the data in the frame format defined in the second protocol may be concatenated into one data, or as individual data Good.

In each embodiment, the number of protocols stored in the storage unit 25b may be plural, and may be changed as appropriate.
In each embodiment, an example of the frame format defined by each protocol has been shown, but the frame format may be in any form.

  In each embodiment, it suffices that either an error detection code or an error correction code exists in the frame format defined by each protocol. That is, an error correction code may be stored in the error detection area A6 instead of the error detection code. The error correction code is a code for detecting an error in the transmission signal and correcting (correcting) the error. In other words, it is sufficient that at least a code capable of detecting an error in the transmission signal exists in the frame format. As the error detection code, any error detection code such as a parity bit, a checksum, or mirror data may be used. As the error correction code, any error correction code such as a BCH code, an RS code, a Hamming code, a turbo code, and a convolutional code may be used.

  In the second embodiment, when the error correction code exists in the frame format, the control unit 25 transmits the transmission signal of the frame format defined by the first protocol and the frame defined by the second protocol. A transmission signal in a frame format in which the error correction code is wrong among the formats is transmitted to the transmission circuit 26. That is, of the error detection code and the error correction code, a code existing in the frame format defined by the second protocol is made erroneous.

  The receiver reception circuit 42 of the receiver 40 causes the receiver control unit 41 to acquire demodulated data when the synchronization bit and the error correction code included in the transmission signal are correct. That is, the receiver control unit 41 of the receiver 40 acquires data when the synchronization bit is correct and the code present in the frame format is correct among the error detection code and the error correction code. Therefore, even when the error detection code is replaced with an error correction code, the same effect as in the second embodiment can be obtained.

In each embodiment, the master CRC code may be replaced with the above-described error detection code or error correction code.
-In each embodiment, any one of the pressure sensor 22 and the temperature sensor 23 should just be provided as a state detection part.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 12 ... Wheel, 13 ... Tire, 21 ... Transmitter (tire condition detection apparatus), 22 ... Pressure sensor (state detection part), 23 ... Temperature sensor (state detection part), 25 ... Control part, 25b ... Storage unit, 26... Transmission circuit (transmission unit), 40... Receiver, 41... Control unit for receiver, 42.

Claims (3)

A tire condition detection device that includes a receiving unit that receives a transmission signal and a control unit for a receiver that acquires data included in the transmission signal, and that transmits the transmission signal to a receiver mounted on a vehicle. ,
A state detector for detecting the state of the tire mounted on the wheel;
A storage unit storing a plurality of types of protocols;
A transmission unit for transmitting a transmission signal including the state of the tire detected by the state detection unit;
A control unit that causes the transmission unit to transmit a transmission signal,
Of the plurality of types of protocols, a protocol corresponding to the receiver is a first protocol, and a protocol different from the protocol corresponding to the receiver is a second protocol.
The control unit sends a transmission signal of a frame format defined by the first protocol and a transmission signal of a frame format in which a synchronization bit in the frame format defined by the second protocol is mistaken to the transmission unit. Tire condition detection device to be transmitted. A tire condition detection device that includes a receiving unit that receives a transmission signal and a control unit for a receiver that acquires data included in the transmission signal, and that transmits the transmission signal to a receiver mounted on a vehicle. ,
A state detector for detecting the state of the tire mounted on the wheel;
A storage unit storing a plurality of types of protocols;
A transmission unit for transmitting a transmission signal including the state of the tire detected by the state detection unit;
A control unit that causes the transmission unit to transmit a transmission signal,
Of the plurality of types of protocols, a protocol corresponding to the receiver is a first protocol, and a protocol different from the protocol corresponding to the receiver is a second protocol.
The control unit includes a frame format transmission signal defined in the first protocol, and a frame format transmission signal in which an error detection code or error correction code in the frame format defined in the second protocol is misleading. Is a tire condition detection device that transmits the transmission to the transmission unit. A tire condition detection device that includes a receiving unit that receives a transmission signal and a control unit for a receiver that acquires data included in the transmission signal, and that transmits the transmission signal to a receiver mounted on a vehicle. ,
A state detector for detecting the state of the tire mounted on the wheel;
A storage unit storing a plurality of types of protocols;
A transmission unit for transmitting a transmission signal including the state of the tire detected by the state detection unit;
A control unit that causes the transmission unit to transmit a transmission signal,
Of the plurality of types of protocols, a protocol corresponding to the receiver is a first protocol, and a protocol different from the protocol corresponding to the receiver is a second protocol.
The control unit transmits a transmission signal having a frame format defined by the first protocol at a first transmission rate at which the receiver can acquire data included in the transmission signal, and is defined by the second protocol. A tire condition detection device that transmits a transmission signal of a frame format that has been transmitted at a second transmission rate that is higher than the first transmission rate.

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