JP4924189B2 - Wheel position detecting device and tire air pressure detecting device having the same - Google Patents

Description

  The present invention relates to a wheel position detection device for detecting at which position of a vehicle a wheel is mounted, and in particular, a transmitter / receiver provided with a pressure sensor on a wheel to which a tire is mounted is directly mounted. It is suitable for application to a direct type tire pressure detecting device that detects tire pressure by transmitting a detection signal from the transmitter / receiver and receiving it by a receiver attached to the vehicle body side.

  Conventionally, there is a direct type as one of tire pressure detecting devices. In this type of tire air pressure detection device, a transmitter / receiver equipped with a sensor such as a pressure sensor is directly attached to a wheel side to which a tire is attached. Also, an antenna and a receiver are provided on the vehicle body side, and when a detection signal from the sensor is transmitted from the transceiver, the detection signal is received by the receiver via the antenna, and tire pressure is detected. To be done.

  In such a direct type tire pressure detecting device, the transmitter / receiver transmits so that it is possible to determine whether the transmitted data belongs to the own vehicle and to which wheel the transmitter / receiver is attached. In the data, ID information for discriminating between the own vehicle and the other vehicle and for discriminating the wheel to which the transceiver is attached is added.

  Then, the ID information is registered in advance on the receiver side, and when the data sent from the transceiver is received, it is determined which wheel the data is from the received ID information. Specifically, when a trigger signal is sent to a transceiver using a trigger machine while the receiver is in a transceiver ID registration mode, data is transmitted from the transceiver to the receiver in synchronization with the trigger signal. ID registration is performed (for example, refer to Patent Document 1).

  However, according to such means, when the user himself / herself changes the position of the wheel, such as tire rotation, the ID information of the wheel rotated by the user is read and the ID information registered so far If it is not registered again, the tire pressure detecting device cannot cope with the wheel position change. Therefore, complicated re-registration work occurs, and there is a problem that work efficiency at the time of tire rotation is deteriorated.

  For this reason, it is desirable to be able to detect the wheel to which each transceiver is attached, that is, the attachment position, without ID information (wheel position information). Or when it is necessary to re-register ID information by the position change of a wheel, it is desired to be able to detect it automatically.

  Therefore, in Patent Document 2, the inventors transmit a trigger signal with a constant intensity from the trigger machine, and also detect the reception intensity of the trigger signal with a transceiver attached to each wheel, and the signal intensity of the trigger signal is Wheel position detection of which wheel each transmitter / receiver is attached to based on the reception intensity of the trigger signal received by each transmitter / receiver by using attenuation as the distance from the trigger device increases We are proposing a new technology to do this.

And so that such wheel position detection can be performed more suitably, each front wheel trigger machine that outputs a trigger signal received only by each transceiver mounted on both front wheels, and each rear wheel mounted Proposing to include a trigger device for a rear wheel that outputs a trigger signal received only by a transceiver.
Japanese Patent No. 3212311 JP 2007-15491 A

  In the above-mentioned patent document 2, it is proposed to detect the wheel position based on the reception intensity itself of the trigger signal. However, the present inventors can detect the wheel position by a new method other than the reception intensity itself. I found out.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a wheel position detection device that can detect which wheel each transceiver is attached without reading ID information by a user.

To achieve the above object, the present invention, the first triggering device and the second triggering device as a trigger signal to perform the measurement of the execution command to perform the measurement of the change in reception strength of the trigger signal to the transceiver It outputs a signal containing run command, transceiver mounted to the left and right front wheels receives the output by the trigger signal of the first triggering device performs measurement of the change in received intensity on the basis of the execution command, the reception intensity and transmits the stored data about the changes to the frame, the transceiver attached to the left and right rear wheels, receives an output the trigger signal of the second triggering device, the measurement of the change in received intensity on the basis of the execution command was carried out, and transmits the stored data relating to changes in the reception intensity in the frame, the second control unit (33) receives the frame, stored in the frame of the attached transceiver to the left and right front wheels Based on the changes in received intensity, as well as identify whether those transceivers attached to any of the left and right front wheels, a reception strength stored in the frame of the attached transceiver to the left and right rear wheels varying The first feature is to identify which of the left and right rear wheels the transmitter / receiver is attached to based on the conversion .

Thus, the first control unit, dissipate measured change in reception strength to transmit and store it in the frame. Change in reception strength is, if the vehicle is traveling, because determined by the relationship between the first, the moving range of the distance and the transceiver from the second triggering device, the first, larger as closer to the second triggering device, The farther away, the smaller. Based on this, it is possible to detect whether at the second control unit, the transceiver on the basis of the change in reception strength is attached to both of the left and right front wheels and left and right rear wheels. Therefore, it can be set as the wheel position detection apparatus which can detect, without reading the transmitter / receiver ID by a user.

  By the way, when the transmitter / receiver is also attached to the spare tire, for example, since the spare tire is arranged between both rear wheels, when the trigger signal is output from the trigger device for the rear wheels, The trigger signal is received by the transmitter / receiver of the three wheels of the spare tire. At this time, according to the method of Patent Document 2, the reception intensity of the trigger signal received by the transmitter / receiver of the spare tire is not so different from the reception intensity of the trigger signal received by the transmitter / receiver of both rear wheels. It may become impossible to distinguish whether the transmitter is attached to both rear wheels or a spare tire.

  However, if the first feature of the present invention is applied to the wheel position detection including the spare tire (6e), the wheel position can be detected separately from the spare tire.

  As an apparatus capable of detecting a spare tire, there is an apparatus disclosed in Japanese Patent No. 3815305. This device has centrifugal force determination means mounted on a transmitter provided on a wheel, compares an identification code including a rotation detection signal with an identification code stored as a running tire, and stores ID information again. ing. However, the centrifugal force detecting means generally cannot detect the centrifugal force unless traveling at 30 km / h or higher, and cannot detect the wheel position including the spare tire at a lower speed than that.

  On the other hand, when the first feature of the present invention is applied to the wheel position detection including the spare tire (6e), since the centrifugal force detecting means is not used, the spare tire can be used even at a lower speed. It becomes possible to detect the wheel positions distinguished.

  Specifically, when the second control unit (33) receives three frames of the transmitter / receiver attached to the left and right rear wheels and the spare tire, the change in the reception intensity is the smallest among the three frames. Identifies the transmitter / receiver attached to the spare tire, and the largest one is attached to the wheel located on the side closer to the second trigger machine (5b) of the right rear wheel (6c) and the left rear wheel (6d). A transmitter / receiver attached to a wheel disposed on the far side from the second trigger device (5b) of the right rear wheel (6c) and the left rear wheel (6d). Can be identified.

  In the first feature of the present invention, vehicle speed determination means (100) for determining whether or not the vehicle speed is equal to or higher than a predetermined speed by inputting data related to the vehicle speed from the vehicle speed detection unit (8) to the second control unit. ) And a trigger command signal that outputs a trigger signal to the trigger machine when the vehicle speed is equal to or higher than a predetermined speed can reliably detect wheel positions that are distinguished from spare tires during traveling. It becomes possible.

Furthermore, in the present invention, the second control unit receives data relating to the vehicle speed from the vehicle speed detection unit (8), measuring the change in reception strength of the trigger signal to the first control unit of the transceiver in response to vehicle speed Provided with time calculation means (100a) for calculating the measurement time (T) to be output, and when outputting a trigger command signal for outputting a trigger signal to the trigger machine, information on the measurement time is also sent to the trigger machine. measurement time information to output the trigger signal, including related measurement time period to the first control unit, and a second feature in that to measure the change in reception strength of the trigger signal.

Thus, determining the measuring time may be caused to measure the change in the reception intensity during the measurement time. Even if it does in this way, the same effect as the 1st feature of the present invention can be acquired.

  The second feature of the present invention can also be applied to wheel position detection including a spare tire. Also in this case, since the centrifugal force detecting means is not used, it is possible to detect the wheel position distinguished from the spare tire even at a lower speed.

  Specifically, when the second control unit (33) receives three frames of the transmitter / receiver attached to the left and right rear wheels and the spare tire, the change in the reception intensity is the smallest among the three frames. Identifies the transmitter / receiver attached to the spare tire, and the largest one is attached to the wheel located on the side closer to the second trigger machine (5b) of the right rear wheel (6c) and the left rear wheel (6d). A transmitter / receiver attached to a wheel disposed on the far side from the second trigger device (5b) of the right rear wheel (6c) and the left rear wheel (6d). Can be identified.

  In the second feature of the present invention, it is preferable that the time calculation means sets the measurement time to the upper limit value when the time corresponding to the vehicle speed exceeds the upper limit value. By providing such an upper limit value, it is possible to prevent the reception intensity measurement time from becoming too long, thereby preventing an increase in battery consumption of the transceiver.

  In the above description, the present invention has been described as a wheel position detection device. However, the wheel position detection device may be incorporated into a tire air pressure detection device.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an overall configuration of a tire air pressure detection device to which a wheel position detection device according to an embodiment of the present invention is applied. The upper direction in the drawing of FIG. 1 corresponds to the front of the vehicle 1, and the lower direction of the drawing corresponds to the rear of the vehicle 1. With reference to this figure, the tire pressure detecting device in the present embodiment will be described.

  As shown in FIG. 1, the tire air pressure detection device is attached to a vehicle 1 and includes a transceiver 2, a receiver 3, a display device 4, and a trigger device 5. In the present embodiment, the transceiver 2, the receiver 3, and the trigger machine 5 correspond to the wheel position detection device of the present invention.

  The transceiver 2 is attached to each of the four wheels 6a to 6d and the spare tire 6e in the vehicle 1, and detects the air pressure of the tires attached to the wheels 6a to 6d and the spare tire 6e, and the detection result is The detection signal data shown is stored and transmitted in a frame to be transmitted. The receiver 3 is attached to the vehicle body 7 side of the vehicle 1 and receives a frame transmitted from the transceiver 2 and performs various processes and calculations based on the detection signal stored therein. Therefore, the tire pressure is obtained. 2A and 2B show block configurations of the transceiver 2 and the receiver 3. FIG.

  As shown in FIG. 2A, the transceiver 2 includes a sensing unit 21, a control unit 22, an RF transmission unit 23, a battery 24, a trigger signal reception unit 25, a transmission antenna 26, and a reception antenna 27. ing.

  The sensing unit 21 includes, for example, a diaphragm type pressure sensor and a temperature sensor, and outputs a detection signal corresponding to the tire pressure and a detection signal corresponding to the temperature.

  The control unit (first control unit) 22 is configured by a known microcomputer including a CPU, a ROM, a RAM, an I / O, and the like, and executes a predetermined process according to a program stored in the ROM or the like.

  Specifically, the control unit 22 receives a detection signal related to the tire pressure from the sensing unit 21, processes the signal, processes the signal as necessary, and indicates the detection result (hereinafter referred to as data related to the tire pressure). Are stored in a frame to be transmitted together with the ID information of each transceiver 2, and then the frame is sent to the RF transmitter 23. The process of sending a signal to the RF transmitter 23 is executed at predetermined intervals according to the program.

When the ignition switch is off, the control unit 22 is normally in a sleep state. However, the control unit 22 receives a trigger signal and switches to a wake-up state when an activation command included in the trigger signal is input. Further, the control unit 22 includes a trigger signal strength measuring unit 22a. When the trigger signal is received from the trigger device 5 through the receiving antenna 27 and the trigger signal receiving unit 25 and the Wake-up state is established, the trigger signal strength is obtained. The measurement intensity of the trigger signal is measured by the measurement unit 22a, and the amplitude of the reception intensity is measured as a value corresponding to a change in the reception intensity during a predetermined time when the tire is assumed to be rotated once or more, for example. Then, the control unit 22 processes the received intensity data as necessary, stores the data related to the received intensity and amplitude in a frame in which data related to the tire pressure is stored, or another frame, and then stores the frame. This is sent to the RF transmitter 23. The measurement of the reception intensity of the trigger signal and the process of transmitting the reception intensity and amplitude data thereof to the RF transmission unit 23 are also performed according to the program.

  FIG. 3 is a diagram showing a frame structure when the reception intensity and amplitude data thereof are stored in a frame in which data relating to tire air pressure is stored in the transceiver 2. As shown in this figure, for example, together with ID information (hereinafter referred to as transceiver ID) attached to distinguish each transceiver 2, the reception intensity of the trigger signal, the amplitude of the reception intensity, the air pressure data, and the temperature Data is stored in the same frame, and this frame is sent to the receiver 3.

  Further, the control unit 22 controls the timing for sending the frame to the RF transmission unit 23. This is to prevent batting between transmission data from each transceiver 2. For example, the transmission timing of how many seconds after the trigger signal is received is set to be different for each transceiver 2 in advance. Therefore, frames are transmitted from the transceivers 2 of the wheels 6a to 6d at different timings.

  However, in order to transmit frames at different timings from the transceivers 2 of the wheels 6a to 6d, each transmission / reception is simply performed by storing different transmission timings in the control unit 22 of each transceiver 2. The stored contents of the machine 2 will be different. For this reason, for example, a map in which the transmission timing can be selected according to the reception intensity or a function expression for obtaining the transmission timing using the transmission intensity as a variable is given to the control unit 22 so that the transmission timing of the frame is shifted according to the reception intensity. If the transmission timing of each transmitter / receiver 2 is inevitably different due to the difference in reception strength, the program of the control unit 22 of all the transmitter / receivers 2 can be made common.

  Moreover, you may set the program memorize | stored in the control part 22 so that transmission timing may be changed at random every time. In this way, if it is changed randomly each time, it is possible to make the transmission timings of the respective transceivers 2 all different with a high probability.

  The RF transmission unit 23 functions as an output unit that transmits a frame transmitted from the control unit 22 to the receiver 3 through the transmission antenna 26 using an RF band, for example, a radio wave of 310 MHz.

  The trigger signal receiving unit 25 functions as an input unit that receives a trigger signal through the receiving antenna 27 and sends it to the control unit 22.

  The battery 24 supplies power to the control unit 22 and the like, and receives power supply from the battery 24 to collect data related to tire air pressure in the sensing unit 21 and various calculations in the control unit 22. Is executed.

  The transceiver 2 configured in this way is attached to an air injection valve in each of the wheels 6a to 6d and the spare tire 6e, for example, and is arranged so that the sensing unit 21 is exposed inside the tire. Thus, the corresponding tire pressure is detected, and the frame is transmitted at predetermined intervals (for example, every minute) through the transmission antenna 26 provided in each transceiver 2.

  As shown in FIG. 2B, the receiver 3 includes an antenna 31, an RF receiver 32, and a controller 33.

  The antenna 31 is a single common antenna that collectively receives frames transmitted from the transceivers 2 and is fixed to the vehicle body 7.

  The RF receiving unit 32 functions as an input unit that receives a frame transmitted from each transceiver 2 by the antenna 31 and sends it to the control unit 33.

  The control unit 33 is configured by a known microcomputer including a CPU, ROM, RAM, I / O, and the like, and executes predetermined processing according to a program stored in the ROM or the like.

  Specifically, the control unit 33 outputs a trigger command signal that instructs the trigger machine 5 to output a trigger signal, receives a frame received by the RF receiving unit 32, and stores each frame stored in the frame. Based on the received intensity data of the trigger signal at the transceiver 2, wheel position detection is performed to identify which of the four wheels 6a to 6d the transmitted frame is for the transceiver 2 attached to. In the case of the present embodiment, the control unit 33 inputs vehicle speed data from the vehicle speed detection unit 8 provided in the vehicle, and triggers the trigger machine 5 when the vehicle speed reaches a predetermined speed (for example, 5 km / h). A command signal is output to detect the wheel position. Examples of the vehicle speed detection unit 8 include a vehicle speed sensor and a wheel speed sensor. If the vehicle speed is calculated by another ECU based on these detection signals, the ECU is used as the vehicle speed detection unit. The data of the calculation result of the vehicle speed may be obtained therefrom.

  Further, the control unit 33 obtains the tire air pressure by performing various signal processing and calculations based on the data indicating the detection result stored in the received frame, and displays an electrical signal corresponding to the obtained tire air pressure. 4 is output. For example, the control unit 33 compares the obtained tire pressure with a predetermined threshold value Th, and outputs a signal to that effect to the display 4 when detecting that the tire pressure has decreased. As a result, the indicator 4 is informed that the tire pressure of any of the four wheels 6a to 6d and the spare tire 6e has decreased.

  As shown in FIG. 1, the display 4 is arranged at a place where the driver can visually recognize, and is configured by an alarm lamp installed in an instrument panel in the vehicle 1, for example. For example, when a signal indicating that the tire air pressure has decreased is sent from the control unit 33 in the receiver 3, the display device 4 notifies the driver of the decrease in tire air pressure by displaying that effect.

  When the trigger command signal sent from the control unit 33 of the receiver 3 is input, the trigger device 5 outputs, for example, a trigger signal having a predetermined signal strength in the LF band of 125 to 135 kHz. It is. As a trigger signal, the thing of the form shown to Fig.4 (a)-(c) can be used, for example.

  FIG. 4A shows a form in which a plurality of frames in which command parts are stored are arranged as trigger signals. Each command part includes a start command and an execution command. The activation command is determined in advance as a command for switching the control unit 22 in the transceiver 2 from the Sleep state to the Wake-up state. The execution command causes the activated control unit 22 to measure the received intensity of the received trigger signal, process the received intensity data as necessary, and store the received intensity data as data related to tire pressure. Alternatively, after storing in a different frame, an operation instruction is given to send the frame to the RF transmitter 23. For example, such a trigger signal is an electromagnetic wave of 125 kHz, and when the transceiver 2 receives a frame storing the first command part, the reception intensity of the subsequent frame storing the second command part is measured. The reception intensity of the trigger signal can be measured. In this example, the trigger signal in which two frames storing the command part are arranged is taken as an example, but the number of frames may be three or more. Further, the frames may be intermittent as shown in FIG. 4A, but may be continuous.

  FIG. 4B shows a form in which the trigger signal is a frame in which a command part and a dummy part are stored. The command part includes a start command and an execution command as described above. The dummy part is used for reception intensity measurement, and may be a modulated signal or a simple carrier signal that is not modulated. For example, such a trigger signal is an electromagnetic wave of 125 kHz, and when the transmitter / receiver 2 receives the command part, the reception intensity of the trigger signal can be measured by measuring the reception intensity of the subsequent dummy part.

  FIG. 4C shows a form in which the trigger signal is a frame in which a signal composed of a pulse train and a dummy part are stored. The pulse train includes a predetermined number (for example, four) of pulse signals CW within a predetermined time ta. This pulse train functions as an activation command for setting the transceiver 2 to the Wake-up state. Each pulse signal CW may be an AM-modulated signal or an unmodulated signal. The dummy part is used for reception intensity measurement as described above. For example, such a trigger signal is an electromagnetic wave of 125 kHz, and when the transmitter / receiver 2 receives a predetermined number (four) of pulse signals CW within a predetermined time ta, the reception intensity of the subsequent dummy part is measured. By doing so, the reception intensity of the trigger signal can be measured.

  The trigger signal shown here is an example, and the trigger signal may have another form. For example, it is possible to divide a frame into a trigger signal for setting the transceiver 2 in a Wake-up state in advance and a trigger signal for measuring reception intensity. In this case, since it is not necessary to use a trigger signal for setting the Wake-up state for reception intensity measurement, the signal intensity may be different from the trigger signal for reception intensity measurement. If the transmitter / receiver 2 is always in the Wake-up state, only the part obtained by removing the start command from the configuration shown in FIGS. 4A and 4B can be used as a trigger signal. .

  The trigger machine 5 includes two units: a first trigger machine 5a arranged on the front wheel side and a second trigger machine 5b arranged on the rear wheel side.

  Each trigger machine 5a, 5b is offset and arrange | positioned with respect to the centerline which divides the vehicle 1 symmetrically so that it may become a different distance with respect to each corresponding wheel. In the present embodiment, the first trigger machine 5a is arranged in the vicinity of the left front wheel 6b, and the second trigger machine 5b is arranged in the vicinity of the left rear wheel 6d, both of which are arranged on the left side of the center line. Yes. Therefore, the distance from the first trigger machine 5a to the right front wheel 6a is longer than the distance from the first trigger machine 5a to the left front wheel 6b, and the distance from the second trigger machine 5b to the right rear wheel 6c. However, it is longer than the distance from the second trigger machine 5b to the left rear wheel 6d.

  Further, in the present embodiment, the trigger signal transmitted from the first trigger machine 5a reaches the transceiver 2 attached to the left and right front wheels 6a, 6b, and the trigger signal transmitted from the second trigger machine 5b is transmitted to the left and right rear wheels 6c. , 6d so as to reach the transmitter / receiver 2.

  The trigger machine 5 may be mounted anywhere as long as the surroundings are not covered with metal, but the place where the trigger machine 5 is not covered with metal as much as possible, and stones etc. do not hit during traveling. For example, it is preferably mounted in a liner or a vehicle interior.

  As described above, the tire air pressure detection device to which the wheel position detection device in the present embodiment is applied is configured.

  Next, the operation of the tire pressure detection device of the present embodiment will be described. The tire air pressure detecting device first detects a wheel position after a predetermined time since an ignition switch (not shown) is switched from OFF to ON. This wheel position detection is performed when the control part 33 of the receiver 3 performs a wheel position detection process.

  FIG. 5 is a flowchart of the wheel position detection process executed by the control unit 33 of the receiver 3. This wheel position detection process is executed when an ignition switch (not shown) is switched from OFF to ON and the controller 33 of the receiver 3 is turned on. FIG. 6 is a flowchart of processing executed by the control unit 22 of each transceiver 2 when a trigger signal is received.

  First, in step 100 shown in FIG. 5, it is determined whether or not the vehicle speed is a predetermined speed, for example, 5 km / h or less. The vehicle speed is obtained by inputting vehicle speed data from the vehicle speed detector 8. Here, the process waits until an affirmative determination is made. This is a state in which the wheels 6a to 6d are not rotating when the vehicle 1 is stopped. Therefore, there is no change in the reception intensity of the trigger signal at the transceiver 2 attached to each of the wheels 6a to 6d. This is because the wheels 6a to 6d and the spare tire 6e cannot be distinguished.

  In step 105, a trigger command signal is output toward the first trigger machine 5a. When this trigger command signal is input to the first trigger machine 5a, a trigger signal having a predetermined signal intensity is output from the first trigger machine 5a to the transceiver 2 attached to the left and right front wheels 6a, 6b. .

On the other hand, as shown in FIG. 6, the transceiver 2 confirms at step 200 whether or not a trigger signal has been received at every predetermined period, and the transmission and reception of the trigger signal attached to the left and right front wheels 6a and 6b. When the signal is input to the control unit 22 through the receiving antenna 27 and the trigger signal receiving unit 25 of the machine 2, the Wake-up state is entered. After the MPU activation process is performed in step 210, the trigger signal is stored in step 220. Receive the command. Then, the trigger signal strength measurement unit 22a measures the reception strength of the trigger signal received in step 230, and measures the amplitude of the reception strength as a value corresponding to a change in the reception strength during a predetermined time in step 240. To do. At this time, the fixed time is, for example, a period in which the tire is assumed to make one rotation or more at the vehicle speed (for example, 5 km / h) determined as the determination criterion in Step 100.

  Subsequently, after measuring the air pressure and temperature in step 250, in step 260, the data of the trigger signal reception intensity and the amplitude of the reception intensity are transmitted together with the transceiver ID, air pressure data, and temperature data of each transceiver 2. Is stored in a frame to be transmitted, and the frame is transmitted to the receiver 3. At this time, since the transmission timings of the respective transceivers 2 are different from each other, the frames transmitted from the respective transceivers 2 can be reliably received by the receiver 3 without interference. In this way, the response of each transceiver 2 is completed.

  Thereby, in the receiver 3, it is determined in step 110 whether or not the two transceivers 2 have responded to the trigger signal output from the first trigger device 5a. As used herein, the two transceivers 2 mean those attached to both front wheels 6a and 6b. The trigger signal is basically set to such an intensity that it can be received by the transceiver 2 attached to both front wheels 6a, 6b, but it is parked near a facility / equipment that emits jamming waves, etc. If the trigger signal is affected by the surrounding environment of the vehicle, the transmitter / receiver 2 may not be able to receive the trigger signal. When at least one of the two transceivers 2 attached to the front wheels 6a and 6b cannot receive the trigger signal, the response from the at least one transceiver 2 is lost. Cannot be received, and it cannot be determined that the two transceivers 2 have responded. In this case, a negative determination is made in step 110, and in order to retry each of the above processes, the process proceeds to step 115, and the count value of a counter (not shown) built in the control unit 33 is incremented by 1, and the number of retries is stored. Keep it.

  In step 115, it is determined whether or not the number of retries is 5 or less, and if it is 5 or less, the process returns to step 105 and retries, and if it exceeds 5 times, the process is stopped without retrying. . In this case, since it is considered that the transmitter / receiver 2 has failed or the battery has run out, the fact may be transmitted through the display 4.

On the other hand, if an affirmative determination is made in step 110, the process proceeds to step 120. In step 120, wheel positions are assigned based on amplitude data, which is a value corresponding to the amount of change in received intensity stored in the received frame. This will be described with reference to FIG. 7 and FIG.

  FIG. 7 is a diagram showing the relationship between the distance from the trigger machine 5 and the intensity of the trigger signal. As shown in this figure, the signal intensity of the trigger signal has a relationship that attenuates as the distance from the trigger machine 5 increases.

  FIGS. 8A and 8B are attached to the front wheels 6a and 6b with respect to the change in the distance between the first trigger device 5a and the transceiver 2 attached to the front wheels 6a and 6b and the travel time of the vehicle 1. FIG. It is the figure which showed the relationship of the change of the reception intensity | strength of the trigger signal in each transmitted / received transmitter / receiver 2.

  As shown to Fig.8 (a), in the front left wheel 6b near the 1st trigger machine 5b, the transmitter / receiver 2 moves in the range shown in figure according to wheel rotation. Since the distance from the 1st trigger machine 5a to the transmitter / receiver 2 is short at this time, the ratio of the variation | change_quantity of the said distance with respect to the distance becomes large. Therefore, the change in the reception strength of the trigger signal is large, and the amplitude of the change in the reception strength is large.

  Moreover, as shown in FIG.8 (b), in the right front wheel 6a far from the 1st trigger machine 5a, the transmitter / receiver 2 moves in the range shown in figure according to wheel rotation. Since the distance from the 1st trigger machine 5a to the transmitter / receiver 2 is long at this time, the ratio of the variation | change_quantity of the said distance with respect to the distance becomes small. Therefore, the change in the reception strength of the trigger signal is small, and the amplitude of the change in the reception strength is small.

  Therefore, it can be specified that the transmitter / receiver 2 that has transmitted a frame having a small amplitude of reception intensity is attached to the right front wheel 6a. And it can specify that the transmitter / receiver 2 which transmitted the flame | frame with a large amplitude of receiving intensity was attached to the left front wheel 6b.

  Based on such knowledge, in step 120, it is determined that the transmitter / receiver 2 that has transmitted a frame having a small reception intensity amplitude is attached to the right front wheel 6a, and the transmission / reception that has transmitted a frame having a large reception intensity amplitude is performed. It is determined that the machine 2 is attached to the left front wheel 6b. The transceiver ID stored in each frame is stored (registered) in the memory in the control unit 33 in association with the right front wheel 6a and the left front wheel 6b to which the transceiver 2 is attached.

  In the subsequent processes of steps 125 to 140, a trigger command signal is output to the second trigger machine 5b in step 125, so that the rear wheels 6c and 6d side are the same as the processes shown in steps 105 to 115 above. Do that. Since these processes are substantially the same as those executed for the front wheels 6a and 6b, the description thereof will be omitted. However, when a trigger signal is output from the second trigger machine 5b, it is added to both the rear wheels 6c and 6d. Since the trigger signal is also received by the transceiver 2 of the spare tire 6e and the three transceivers 2 respond and transmit frames, whether or not the three transceivers 2 respond in step 130. The only difference is in determining whether or not.

Thereby, it is determined whether or not the received frame includes a response due to the transceiver 2 attached to the spare tire 6e. If an affirmative determination is made here, the process proceeds to step 140, and the data of the amplitude of the reception intensity indicating the value corresponding to the change amount of the transceiver ID and the reception intensity is read from the three frames. Then, based on the amplitude of the received intensity, it is determined whether the transceiver 2 that has transmitted the frame is of the spare tire 6e or of the rear wheels 6c and 6d. This will be described with reference to FIG.

  9 (a) to 9 (c) show the change in distance between the second trigger machine 5b and the transceiver 2 attached to the rear wheels 6c and 6d and the spare tire 6e and the rear of the vehicle 1 with respect to the travel time. It is the figure which showed the relationship of the change of the reception intensity | strength of the trigger signal in each transmitter / receiver 2 attached to wheel 6c, 6d and spare tire 6e.

  As shown in FIG. 9A, in the left rear wheel 6d closest to the second trigger machine 5b, the transceiver 2 moves within the range shown in the drawing corresponding to the wheel rotation. Since the distance from the 2nd trigger machine 5b to the transmitter / receiver 2 is short at this time, the ratio of the variation | change_quantity of the said distance with respect to the distance becomes large. Therefore, the change in the reception strength of the trigger signal is large, and the amplitude of the change in the reception strength is large.

  Moreover, as shown in FIG.9 (b), in the right rear wheel 6c furthest from the 2nd trigger machine 5b, the transmitter / receiver 2 moves in the range shown in the figure corresponding to wheel rotation. Since the distance from the 2nd trigger machine 5b to the transmitter / receiver 2 is long at this time, the ratio of the variation | change_quantity of the said distance with respect to the distance becomes small. Therefore, the change in the reception strength of the trigger signal is small, and the amplitude of the change in the reception strength is small.

  Furthermore, as shown in FIG.9 (c), in the spare tire 6e, since wheel rotation does not arise, the transmitter / receiver 2 does not move. Therefore, the change in the reception intensity of the trigger signal does not occur, and the amplitude of the change in the reception intensity becomes almost zero.

  Therefore, it can be specified that the transceiver 2 that has transmitted the frame having the smallest amplitude of reception intensity is attached to the spare tire 6e. A transceiver 2 that has transmitted a frame having the largest amplitude of reception intensity is attached to the left rear wheel 6d, and a transceiver 2 that has transmitted a frame having the second smallest (largest) amplitude of reception intensity. It can be identified as being attached to the right rear wheel 6c.

  Based on such knowledge, in Step 140, the transceiver 2 that has transmitted the frame with the smallest received intensity amplitude is the spare tire 6e, and the transceiver 2 that has transmitted the frame with the largest received intensity amplitude is the left. It is determined that the transmitter / receiver 2 that has transmitted the rear wheel 6d and the frame having the second smallest (larger) amplitude of received intensity is attached to the right rear wheel 6c. Then, the transceiver ID stored in each frame is stored (registered) in the memory in the control unit 33 in association with the right rear wheel 6c, the left rear wheel 6d, and the spare tire 6e to which the transceiver 2 is attached. In this way, the wheel position detection process ends.

  As a result, when the tire 3 detects tire pressure, which will be described later, when a frame in which data relating to tire pressure is stored is transmitted, the receiver 3 transmits / receives a frame from the transceiver ID stored in the frame. It is possible to determine which of the four wheels 6a to 6d the machine 2 is attached to and determine the tire pressure of each wheel 6a to 6d. Therefore, it is possible to detect which of the wheels 6a to 6d is attached to each of the transceivers 2 without reading the transceiver ID by the user.

  Then, the tire air pressure detecting device detects the tire air pressure after detecting the wheel position in this way.

  Specifically, the tire air pressure detection device is in a periodic transmission mode, and as described above, in each transceiver 2, a detection signal indicating the tire air pressure from the sensing unit 21 or the temperature in the tire is input to the control unit 22. The Then, the detection signal is processed as necessary to obtain data relating to tire air pressure, and is stored in a frame to be transmitted together with the transmitter / receiver ID of each transmitter / receiver 2, and then passed through the RF transmitter 23 at predetermined intervals. It is transmitted to the receiver 3 side.

  On the other hand, when a frame is transmitted from the transceiver 2, it is received by the antenna 31 of the receiver 3 and input to the controller 33 through the receiver 32. Then, in the control unit 33, data indicating the tire pressure and data indicating the temperature in the tire are extracted from the received frame, temperature correction is performed as necessary based on the data indicating the temperature, and the tire pressure is obtained. At this time, since the transceiver ID is stored in the frame, the transceiver 2 is collated with the transceiver ID stored at the time of wheel position detection, and the frame is attached to any of the four wheels 6a to 6d. It is determined whether it is sent from.

  When the change in the tire pressure is small such that the difference between the calculated tire pressure and the previously determined tire pressure does not exceed a predetermined threshold, the cycle for detecting the tire pressure remains unchanged (for example, 1 If the change in tire air pressure is large exceeding a predetermined threshold, the cycle is advanced (for example, every 5 seconds).

  Thereafter, if it is determined that the obtained tire pressure is below a predetermined threshold value, a signal indicating that is output from the control unit 33 to the display unit 4, and the tire pressure has decreased. It is displayed on the display 4 in a form that can identify which of the wheels 6a to 6d. Thereby, it becomes possible to notify the driver which tire pressure of the wheels 6a to 6d has decreased.

  Finally, when the ignition switch is switched from on to off, a trigger command signal is output from the control unit 33 of the receiver 3 to the trigger unit 5 again, and a trigger signal is output from the trigger unit 5. When the trigger signal is input to the control unit 22 through the receiving antenna 27 and the trigger signal receiving unit 25, the transceiver 2 is switched to the Sleep state. Thereby, the tire air pressure detection of the tire air pressure detecting device is completed.

  By the tire air pressure detection device provided with the wheel position detection device of the present embodiment described above, it is determined whether the transmitter / receiver 2 is attached to the wheels 6a to 6d or the spare tire 6e, by reading the transmitter / receiver ID by the user, etc. It can be set as the wheel position detection apparatus which can detect even if it does not perform. And since it is not what uses a centrifugal force detection means etc., it becomes possible to detect the wheel position distinguished from the spare tire even at a lower speed.

(Second Embodiment)
A second embodiment of the present invention will be described. In the above embodiment, the wheel position is detected when the vehicle speed is equal to or higher than the predetermined speed, and the measurement of the reception intensity of the trigger signal in each transmitter / receiver 2 is performed for a certain period of time, thereby obtaining a value corresponding to a change in the reception intensity. The amplitude of the received intensity is measured, but in this embodiment, the time for measuring the received intensity of the trigger signal in each transceiver 2 is set according to the vehicle speed, and the maximum received intensity during that time is set. Find the difference between the value and the minimum value. In addition, since this embodiment changes the process which the control part 33 by the side of the receiver 3 performs with respect to 1st Embodiment, and others are the same as that of 1st Embodiment, only about a different part. explain.

  FIG. 10 is a flowchart of a wheel position detection process executed by the control unit 33 on the receiver 3 side in the tire air pressure detection device of the present embodiment. As shown in this figure, in this process, the process of step 100a is executed instead of the process of step 100 in FIG. 5 of the first embodiment.

  That is, in step 100a, based on the vehicle speed data received from the vehicle speed detection unit 8, a time T during which the transceiver 2 measures the reception intensity of the trigger signal is set. The amplitude of the reception intensity described above means the maximum value and the minimum value of the amplitude waveform of the reception intensity. However, when the vehicle 1 is very low speed, the time required for one rotation of the tire is very long. It becomes long. For example, the relationship between the vehicle speed and the time required for one rotation of the tire is shown in FIG. 11, and the time required for one rotation of the tire increases as the vehicle speed decreases. Basically, it is preferable to set the time for measuring the reception intensity so that the reception intensity of the trigger signal corresponding to one or more rotations of the tire can be obtained, but if the measurement time is too long, The consumption of the battery 24 will increase.

  For this reason, in step 100a, the time required for one rotation of the tire is determined based on the vehicle speed. If the time does not exceed the predetermined upper limit value, the time is set as time T, and the upper limit value is set. If it exceeds, the upper limit value is set as time T.

  In step 105, when a trigger command signal is transmitted to the first trigger machine 5a, information on the time T is also transmitted. Then, information related to time T is included in the trigger command included in the trigger signal, and information related to time T is transmitted to each transmitter / receiver 2, and the reception intensity of the trigger signal is measured during the time T. Based on this, the control unit 22 of each transceiver 2 calculates the difference ΔS between the maximum value and the minimum value of the reception intensity of the trigger signal obtained during a predetermined time. In this case, if the time T is shorter than the rotation equivalent to one rotation of the tire, the trigger intensity data corresponding to one rotation of the tire cannot be obtained. Therefore, the maximum value and the minimum value are the amplitude waveforms of the reception intensity. Although there is a possibility that the local maximum value and the local minimum value are not reached, the same can be said for both front wheels 6a and 6b. Therefore, the magnitude relationship between the magnitudes of the difference ΔS between the maximum value and the minimum value of the reception intensity is eventually the first trigger. It depends on the distance from the machine 5a. For this reason, in step 120a, it is possible to compare the magnitude of the difference ΔS between the maximum value and the minimum value of the received intensity without any problem, and which of the right front wheel 6a and the left front wheel 6b the transmitter / receiver 2 is attached to. Can be identified. Steps 110 and 115 are the same processes as those in the first embodiment, and thus description thereof is omitted here.

  On the other hand, when the trigger command signal is transmitted to the second trigger machine 5b in step 125, information on the time T is also transmitted. Thereby, in steps 130, 135 and 140a, the same processing as in steps 110, 115 and 120a is performed. Also in this case, the difference ΔS between the maximum value and the minimum value of the reception intensity at the transceiver 2 attached to the rear wheels 6c and 6d can be said to be the same as that on the front wheel side. By comparing the magnitude of the difference ΔS between the value and the minimum value, it is possible to identify which of the right rear wheel 6c and the left rear wheel 6d the transmitter / receiver 2 is attached without any problem.

(Third embodiment)
A third embodiment of the present invention will be described. In each of the above-described embodiments, the case where the two trigger machines 5 such as the first and second trigger machines 5a and 5b are arranged in the vicinity of the left front wheel 6b and the left rear wheel 6d has been described, but each wheel 6a other than the spare tire 6e is described. The present invention can also be applied to the case where one trigger machine 5 is arranged in the vicinity of each of ˜6d. FIG. 12 is a block diagram showing the overall configuration of the tire air pressure detection device when one trigger machine 5 is arranged in the vicinity of each of the wheels 6a to 6d. FIG. 13 is a diagram showing a state when a trigger signal is output from the trigger device 5 corresponding to the right rear wheel 6c in the embodiment shown in FIG.

  As shown in FIG. 12, 1st-4th trigger machine 5a-5d is arrange | positioned corresponding to each wheel 6a-6d. Basically, the trigger signal intensity is set so that the trigger signals output from the first to fourth trigger machines 5a to 5d are received by the transceiver 2 attached to the corresponding wheels 6a to 6d. Yes, when a trigger signal is output from the third and fourth trigger machines 5c and 5d corresponding to the rear wheels 6c and 6d, the trigger signal is also received by the transceiver 2 of the spare tire 6e.

  Also in such a form, for example, as in the first embodiment, when the vehicle speed is equal to or higher than a predetermined speed, trigger command signals are sequentially output to the first to fourth trigger machines 5a to 5d. A trigger signal is output to each transceiver 2 attached to each wheel 6a-6d. At this time, as shown in FIG. 13A, when a trigger signal is output from the third and fourth trigger devices 5c and 5d corresponding to the rear wheels 6c and 6d, the transmitter / receiver 2 of the spare tire 6e is also triggered. Since the signal is received, a response is also returned from the transceiver 2 of the spare tire 6e as shown in FIG. 13 (b).

  Therefore, the control unit 33 on the receiver 3 side determines whether or not there is a response from the two transceivers 2 when the trigger signal is output from the third trigger device 5c or the fourth trigger device 5d. If there is one, the magnitude of the amplitude of the received intensity is read from the received frame. The transmitter / receiver 2 that has transmitted the frame having the smaller amplitude of the reception intensity is attached to the spare tire 6e, and the transmitter / receiver 2 that has transmitted the larger frame is the right rear wheel 6c or the left rear. It can be identified as being attached to the ring 6d.

  As described above, the present invention can also be applied to the case where the trigger machines 5 are arranged one by one in the vicinity of each of the wheels 6a to 6d other than the spare tire 6e, and the same effects as described above can be obtained. Although the case where the vehicle speed is equal to or higher than the predetermined speed has been described here as in the first embodiment, the case where the time T for measuring the reception intensity is determined based on the vehicle speed as in the second embodiment is also described. The same can be said for the above.

(Other embodiments)
In the above embodiment, the transmitter / receiver 2 is distinguished from the wheels 6a to 6d or the spare tire 6e based on the value corresponding to the change in the reception intensity, but based on the change in the reception intensity itself. May be distinguished.

  Moreover, although the said embodiment demonstrated the case where the 1st, 2nd trigger machine 5a, 5b was arrange | positioned, one trigger machine 5 is arrange | positioned in the distance which is different from the transmitter / receiver 2 of each wheel 6a-6e. In this manner, the wheel position may be detected using only one trigger machine 5. Moreover, in the said embodiment, although the case where the 1st, 2nd trigger machine 5a, 5b was offset to the left direction with respect to the centerline of the vehicle 1 was demonstrated, both may be offset to the right direction, It may be offset in different directions.

  Moreover, although the said embodiment demonstrated the form with which the antenna 31 was made into one common antenna, you may be a form where four are provided corresponding to each wheel 6a-6d. However, when the antenna 31 is a common antenna, it is particularly difficult to specify the wheels 6a to 6d to which the transceiver 2 is attached. Therefore, it is effective to apply the present invention to a shared antenna. .

  In the above embodiment, the wheel position is detected a predetermined time after the ignition switch is switched from OFF to ON. However, the wheel position may be detected at other times. For example, it may be performed after tire rotation or after tire replacement. Whether tire rotation or tire replacement has been performed can be determined based on the detection of the inclination of the vehicle body 7 by, for example, pressing a wheel position detection switch (not shown) installed in the vehicle or by installing an inclination sensor on the vehicle body. .

  Moreover, although the said embodiment demonstrated what applied one Embodiment of this invention with respect to a four-wheel vehicle, it was not restricted to a four-wheel vehicle, More wheels were provided like a large vehicle. The present invention can also be applied to vehicle wheel position detection devices and tire air pressure detection devices.

  In the first embodiment, the vehicle speed detection unit 8 is provided so that the wheel position is detected when the vehicle speed is equal to or higher than the predetermined speed. However, this can be more reliably distinguished from the spare tire 6e. Therefore, this may not be provided.

Further, in each of the above-described embodiments, the case where the wheel position is detected for the spare tire 6e in addition to the four wheels 6a to 6d serving as the traveling wheels has been described. Of course, only the four wheels 6a to 6d serving as the traveling wheels are used. It is also possible to perform position detection based on a value corresponding to the amount of change in reception intensity. This is not limited to a vehicle that does not include the spare tire 6e, and the spare tire 6e is not equipped with the transceiver 2 or the trigger tire is not received by the transceiver 2 of the spare tire 6e. It is effective for.

1 is a block diagram illustrating an overall configuration of a tire air pressure detection device to which a wheel position detection device according to a first embodiment of the present invention is applied. It is the figure which showed the block configuration of the transmitter / receiver and receiver of the tire pressure detection apparatus shown in FIG. It is the figure which showed the frame structure when the receiving intensity data was stored in the flame | frame in which the data regarding tire air pressure were stored in the transmitter / receiver. It is the schematic diagram which showed the form of the trigger signal. It is a flowchart of the wheel position detection process which the control part of a receiver performs. It is a flowchart of the process which the control part of a transmitter / receiver performs. It is the graph which showed the relationship between the distance from a trigger machine, and the intensity | strength of a trigger signal. The figure which showed the relationship between the change of the distance between the 1st trigger machine and the transmitter / receiver attached to the front wheel, and the change of the reception intensity | strength of the trigger signal in each transmitter / receiver attached to the front wheel with respect to the driving time of a vehicle. It is. Changes in distance between the second trigger machine and the transmitter / receiver attached to the rear wheel or the spare tire, and the trigger signal reception intensity at each transmitter / receiver attached to the rear wheel or the spare tire with respect to the traveling time of the vehicle It is the figure which showed the relationship of change. It is a flowchart of the wheel position detection process which the control part by the side of the receiver of the tire pressure detection apparatus concerning 2nd Embodiment of this invention performs. It is the graph which showed the relationship between a vehicle speed and the time required for one rotation of a tire. It is a block diagram which shows the whole structure of a tire air pressure detection apparatus when the trigger machine is arrange | positioned 1 each in the vicinity of each wheel. FIG. 13 is a diagram illustrating a state when a trigger signal is output from a trigger machine corresponding to the right rear wheel in the tire air pressure detection device illustrated in FIG. 12.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Transmitter / receiver, 3 ... Receiver, 4 ... Display, 5 ... Trigger machine, 5a ... 1st trigger machine, 5b ... 2nd trigger machine, 6a ... Right front wheel, 6b ... Left front wheel, 6c ... Right rear wheel, 6d ... left rear wheel, 7 ... vehicle body, 8 ... vehicle speed detection unit, 21 ... sensing unit, 22 ... control unit, 23 ... RF transmission unit, 24 ... battery, 25 ... trigger signal reception unit, 26 ... transmission Antenna, 27 ... receiving antenna, 31 ... antenna, 32 ... RF receiver, 33 ... controller.

Claims (10)

A receiving unit (25) that is attached to each of the left and right front wheels (6a, 6b) and the left and right rear wheels (6c, 6d) and receives the trigger signal; and the reception intensity of the trigger signal received by the receiving unit with measuring a change, the first control unit for storing data representing the change in the receiving intensity obtained in the frame (22), transmitting unit for transmitting the frame that has been processed by the first control unit (23 A transceiver (2) comprising:
Provided on the vehicle body (7) side, disposed on the left and right front wheels side of the left and right rear wheels, and disposed at different distances from the right front wheel (6a) and the left front wheel (6b) constituting the left and right front wheels, A first trigger device (5a) that outputs the trigger signal that can be received by the transceiver mounted on the left and right front wheels; and a right that is disposed closer to the left and right rear wheels than the left and right front wheels and that constitutes the left and right rear wheels A second trigger device (5b) that is disposed at a different distance from the rear wheel (6c) and the left rear wheel (6d) and outputs the trigger signal that can be received by at least the transceiver mounted on the left and right rear wheels. Trigger machine (5);
Wherein provided on the vehicle body side, the reception unit for receiving the frame (32), based on the change of the reception intensity which the data stored in the frame is represented, both the transceiver of the plurality of wheels A receiver (3) provided with a second control unit (33) for determining whether it is attached to
The first triggering device and the second triggering device, as the trigger signal, the signal including an execution command to perform a measurement execution command to perform the measurement of the change of the reception strength of the trigger signal to the transceiver Output,
The transceiver mounted on the left and right front wheels, upon receiving the trigger signal output of the first triggering device performs measurement of the change of the reception strength based on said execution command, changes the reception intensity data transmission and stored in the frame about the,
The transceiver attached to the left and right rear wheels, upon receiving the trigger signal output of the second triggering device performs measurement of the change of the reception strength based on said execution command, the change of the reception strength Store data in the frame and send it,
The second control unit (33) receives the frame, based on the change of said reception strength stored in said frame of the transceiver attached to the left and right front wheels, wherein the transceiver is the right and left with identifying whether those attached to either of the front wheels, based on changes in the said reception strength stored in the frame of the transceiver attached to the left and right rear wheels, wherein the transceiver is the A wheel position detection device that identifies which of the left and right rear wheels is attached. The left and right front wheels (6a, 6b), the left and right rear wheels (6c, 6d) and the spare tire (6e) are attached to the wheels, respectively, and a receiving unit (25) that receives a trigger signal; with measuring a change in reception strength of the trigger signal, a first control unit for storing data representing the change in the receiving intensity obtained in the frame (22), the frames processed by the first control unit A transceiver (2) having a transmitter (23) for transmitting;
Provided on the vehicle body (7) side, disposed on the left and right front wheels side of the left and right rear wheels, and disposed at different distances from the right front wheel (6a) and the left front wheel (6b) constituting the left and right front wheels, A first trigger device (5a) that outputs the trigger signal that can be received by the transceiver mounted on the left and right front wheels; and a right that is disposed closer to the left and right rear wheels than the left and right front wheels and that constitutes the left and right rear wheels A second trigger device (5b) that is disposed at a different distance from the rear wheel (6c) and the left rear wheel (6d) and outputs the trigger signal that can be received by at least the transceiver mounted on the left and right rear wheels. Trigger machine (5);
Wherein provided on the vehicle body side, the reception unit for receiving the frame (32), based on the change of the reception intensity which the data stored in the frame is represented, wherein the transceiver is a plurality of wheels and spare A receiver (3) including a second control unit (33) for determining which of the tires (6e) is attached,
The first triggering device and the second triggering device, as the trigger signal, the signal including an execution command to perform a measurement execution command to perform the measurement of the change of the reception strength of the trigger signal to the transceiver Output,
The transceiver mounted on the left and right front wheels, upon receiving the trigger signal output of the first triggering device performs measurement of the change of the reception strength based on said execution command, changes the reception intensity data transmission and stored in the frame about the,
The left and right rear wheels and the transceiver attached to the spare tire, when receiving the trigger signal output of the second triggering device performs measurement of the change of the reception strength based on said execution command, the data about changes in the reception intensity transmitted and stored in the frame,
The second control unit (33) receives the frame, based on the change of said reception strength stored in said frame of the transceiver attached to the left and right front wheels, wherein the transceiver is the right and left with identifying whether those attached to either of the front wheels, based on changes in the said reception strength stored in the frame of the transceiver attached to the left and right rear wheels and the spare tire, wherein A wheel position detection device that identifies whether the transceiver is attached to the left and right rear wheels or the spare tire.   When the second control unit (33) receives three frames of the transmitter / receiver attached to the left and right rear wheels and the spare tire, the change of the reception intensity is the smallest among the three frames. Is identified as the transmitter / receiver attached to the spare tire, and the largest one is arranged on the side closer to the second trigger machine (5b) among the right rear wheel (6c) and the left rear wheel (6d) The transmitter / receiver attached to the wheel is specified, and the second smallest wheel is the wheel arranged on the far side from the second trigger device (5b) among the right rear wheel (6c) and the left rear wheel (6d). The wheel position detection device according to claim 2, wherein the wheel position detection device is specified as a transceiver attached to the vehicle.   The second control unit includes vehicle speed determination means (100) that receives data related to the vehicle speed from the vehicle speed detection unit (8) and determines whether the vehicle speed is equal to or higher than a predetermined speed, and the vehicle speed is the predetermined speed. The tire pressure detecting device according to any one of claims 1 to 3, wherein a trigger command signal for outputting the trigger signal to the first and second trigger devices is output at the time described above. A receiving unit (25) that is attached to each of the left and right front wheels (6a, 6b) and the left and right rear wheels (6c, 6d) and receives the trigger signal; and the reception intensity of the trigger signal received by the receiving unit with measuring a change, the first control unit for storing data representing the change in the receiving intensity obtained in the frame (22), transmitting unit for transmitting the frame that has been processed by the first control unit (23 A transceiver (2) comprising:
Provided on the vehicle body (7) side, disposed on the left and right front wheels side of the left and right rear wheels, and disposed at different distances from the right front wheel (6a) and the left front wheel (6b) constituting the left and right front wheels, A first trigger device (5a) that outputs the trigger signal that can be received by the transceiver mounted on the left and right front wheels; and a right that is disposed closer to the left and right rear wheels than the left and right front wheels and that constitutes the left and right rear wheels A second trigger device (5b) that is disposed at a different distance from the rear wheel (6c) and the left rear wheel (6d) and outputs the trigger signal that can be received by at least the transceiver mounted on the left and right rear wheels. Trigger machine (5);
Wherein provided on the vehicle body side, the reception unit for receiving the frame (32), based on the change of the reception intensity which the data stored in the frame is represented, both the transceiver of the plurality of wheels A receiver (3) provided with a second control unit (33) for determining whether it is attached to
The second control unit receives data relating to the vehicle speed from the vehicle speed detection unit (8), measurements corresponding to the vehicle speed is measured change in reception strength of the trigger signal to the first control unit of the transceiver Including a time calculation means (100a) for calculating time (T), and when outputting a trigger command signal for outputting the trigger signal to the trigger machine, information on the measurement time is also sent to the trigger machine,
The first triggering device and the second triggering device, as the trigger signal, causes measurement made of the execution commands to perform the measurement of the change of the reception strength of the trigger signal to the transceiver, wherein the measurement Outputs a signal containing an execution command to be performed for the measurement time,
The transceiver mounted on the left and right front wheels, upon receiving the trigger signal output of the first triggering device, the measurement is performed time period measured change of the reception strength based on said execution command, the receiving data about changes in the intensity transmitted and stored in the frame,
The left and right rear the transceiver attached to the wheel, when receiving the trigger signal output of the second triggering device, the measurement is performed time period measured change of the reception strength based on said execution command, the data about changes in the reception intensity transmitted and stored in the frame,
The second control unit (33) receives the frame, based on the change of said reception strength stored in said frame of the transceiver attached to the left and right front wheels, wherein the transceiver is the right and left with identifying whether those attached to either of the front wheels, based on changes in the said reception strength stored in the frame of the transceiver attached to the left and right rear wheels, wherein the transceiver is the A wheel position detection device that identifies which of the left and right rear wheels is attached. The left and right front wheels (6a, 6b), the left and right rear wheels (6c, 6d) and the spare tire (6e) are attached to the wheels, respectively, and a receiving unit (25) that receives a trigger signal; with measuring a change in reception strength of the trigger signal, a first control unit for storing data representing the change in the receiving intensity obtained in the frame (22), the frames processed by the first control unit A transceiver (2) having a transmitter (23) for transmitting;
Provided on the vehicle body (7) side, disposed on the left and right front wheels side of the left and right rear wheels, and disposed at different distances from the right front wheel (6a) and the left front wheel (6b) constituting the left and right front wheels, A first trigger device (5a) that outputs the trigger signal that can be received by the transceiver mounted on the left and right front wheels; and a right that is disposed closer to the left and right rear wheels than the left and right front wheels and that constitutes the left and right rear wheels A second trigger device (5b) that is disposed at a different distance from the rear wheel (6c) and the left rear wheel (6d) and outputs the trigger signal that can be received by at least the transceiver mounted on the left and right rear wheels. Trigger machine (5);
Wherein provided on the vehicle body side, the reception unit for receiving the frame (32), based on the change of the reception intensity which the data stored in the frame is represented, wherein the transceiver is a plurality of wheels and spare A receiver (3) including a second control unit (33) for determining which of the tires (6e) is attached,
The second control unit receives data relating to the vehicle speed from the vehicle speed detection unit (8), measurements corresponding to the vehicle speed is measured change in reception strength of the trigger signal to the first control unit of the transceiver Including a time calculation means (100a) for calculating time (T), and when outputting a trigger command signal for outputting the trigger signal to the trigger machine, information on the measurement time is also sent to the trigger machine,
The first triggering device and the second triggering device, as the trigger signal, causes measurement made of the execution commands to perform the measurement of the change of the reception strength of the trigger signal to the transceiver, wherein the measurement Outputs a signal containing an execution command to be performed for the measurement time,
The transceiver mounted on the left and right front wheels, upon receiving the trigger signal output of the first triggering device performs measurement of the change of the reception strength based on said execution command, changes the reception intensity the data transmission stored in said frame,
The left and right rear wheels and the transceiver attached to the spare tire, when receiving the trigger signal output of the second triggering device, the measurement time measured change of the reception strength based on said execution command perform minute, and transmits the stored data of the change of the reception strength to the frame,
The second control unit (33) receives the frame, based on the change of said reception strength stored in said frame of the transceiver attached to the left and right front wheels, wherein the transceiver is the right and left with identifying whether those attached to either of the front wheels, based on changes in the said reception strength stored in the frame of the transceiver attached to the left and right rear wheels and the spare tire, wherein A wheel position detection device that identifies whether the transceiver is attached to the left and right rear wheels or the spare tire.   When the second control unit (33) receives three frames of the transmitter / receiver attached to the left and right rear wheels and the spare tire, the change of the reception intensity is the smallest among the three frames. Is identified as the transmitter / receiver attached to the spare tire, and the largest one is arranged on the side closer to the second trigger machine (5b) among the right rear wheel (6c) and the left rear wheel (6d) The transmitter / receiver attached to the wheel is specified, and the second smallest wheel is the wheel arranged on the far side from the second trigger device (5b) among the right rear wheel (6c) and the left rear wheel (6d). The wheel position detection device according to claim 7, wherein the wheel position detection device is specified as a transceiver attached to the vehicle. The wheel according to any one of claims 5 to 7 , wherein when the time corresponding to the vehicle speed exceeds an upper limit value, the time calculation means sets the measurement time to the upper limit value. Position detection device. The plurality of wheels include two front wheels (6a, 6b) and two rear wheels (6c, 6d),
The trigger machine is disposed on the two front wheels side of the two rear wheels and is disposed at a different distance from the right front wheel (6a) and the left front wheel (6b) constituting the two front wheels. It is arranged at a different distance from the right rear wheel (6c) and the left rear wheel (6d) which are disposed on the rear wheel two side with respect to the machine (5a) and the two front wheels. wheel position detecting device according to any one of claims 1 to 8, characterized in that the second is constructed and a triggering device (5b) was. A tire pressure detection device including the wheel position detection device according to any one of claims 1 to 9 ,
The transceiver includes a sensing unit (21) that outputs a detection signal related to air pressure of the tire provided in each of the plurality of wheels, and the detection signal of the sensing unit is signal-processed by the first control unit. After that, it is sent via the transmitter,
In the tire pressure detecting device, the receiver is configured to obtain air pressures of the tires provided to the plurality of wheels based on the detection signals in the second control unit.

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