JP4175348B2 - Wheel position detecting device and tire air pressure detecting device having the same - Google Patents

Description

  The present invention relates to a wheel position detecting device for detecting a position where a wheel is mounted on a vehicle, and in particular, a transmitter having a pressure sensor attached directly to a wheel to which a tire is mounted, and the pressure sensor. The detection signal from the transmitter is transmitted from the transmitter, and is received by a receiver attached to the vehicle body side, so that it is suitable for application to a direct tire pressure detection device that detects tire pressure.

  Conventionally, there is a direct type as one of tire pressure detecting devices. In this type of tire pressure detecting device, a transmitter equipped with a sensor such as a pressure sensor is directly attached to a wheel side to which a tire is attached. In addition, an antenna and a receiver are provided on the vehicle body side. When a detection signal from the sensor is transmitted from the transmitter, 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 transmits so that it can be determined whether the transmitted data belongs to the own vehicle and which wheel the transmitter is attached to. In the data, ID information for discriminating whether the vehicle is a host vehicle or another vehicle and discriminating a wheel to which a transmitter is attached is added.

Then, the ID information is registered in advance on the receiver side, and when the data sent from the transmitter is received, it is determined which wheel the data is from the received ID information ( For example, see Patent Document 1).
Japanese Patent No. 3212311

  As described above, in the conventional tire pressure detection device, the ID information determined for each wheel is included in the data transmitted from the transmitter so that the wheel to which the transmitter is attached can be identified. It has become. For this reason, if there is no ID information added to each wheel, it is impossible to determine which wheel corresponds to the data from the transmitter. That is, if the ID information is not used, it is impossible to detect at which position of the vehicle each transmitter is located.

  Further, according to the above 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 is read again. Without re-registration, the tire pressure detector cannot cope with the wheel position change.

  For this reason, it is desirable to be able to detect the wheel to which each transmitter 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.

  In view of the above points, the present invention has as its first object to provide a wheel position detection device that can detect which wheel each transmitter is attached to without needing to read ID information by the user. To do.

  A second object is to enable detection of which wheel each transmitter is attached to without using ID information.

In order to achieve the above object, according to the first aspect of the present invention, only one trigger machine (5) for outputting a trigger signal is provided on the vehicle body (7) side, and a plurality of wheels (6a to 6d) having tires are provided. ) Each of the transmitters (2) provided with each receives the trigger signal, obtains the reception intensity of the trigger signal, stores reception intensity data representing the obtained reception intensity in the transmission frame, and is provided on the vehicle body side. To the receiver (3). Then, at the receiver, transmission is performed based on the relationship between the order of the received intensity represented by the received intensity data stored in the transmission frame and the distance from the trigger machine to the transmitter attached to each of the plurality of wheels. It is characterized by determining which of the plurality of wheels the machine is attached to.

  In this way, it is possible to specify from the reception intensity data stored in each transmission frame whether the transmission frame is transmitted from a transmitter attached to a plurality of wheels. Thereby, it can be set as the wheel position detection apparatus which can detect to which wheel each transmitter is attached, without reading ID information by a user.

Furthermore, in invention of Claim 1, a trigger machine is arrange | positioned in the place of a different distance from each of several wheel, and it was attached to each of several wheel from the trigger machine in the 2nd control part (32b). It is characterized in that it is determined which of the plurality of wheels the transmitter is attached on the assumption that the order in which the distance to the transmitter is close matches the order in which the reception intensity is large.

  In this way, if the trigger machine is arranged at a different distance from each of the plurality of wheels, the reception intensity of the trigger signal at each transmitter is all different. For this reason, the order in which the distance from the trigger machine to the transmitter attached to each of the plurality of wheels is the same as the order in which the reception intensity is large matches, and the transmitter is attached to any of the plurality of wheels. It is possible to determine whether or not.

  In this case, the trigger device outputs a trigger signal having a signal strength that cannot be received by the transmitter attached to the wheel farthest from the trigger device among the plurality of wheels as the trigger signal. In the receiver, in the receiver, in the second control unit, the transmitter to which no transmission frame has been sent is attached to the wheel farthest from the trigger machine among the plurality of wheels. Can be determined.

According to the second or fourth aspect of the invention, in the transmitter, when the first control unit creates a transmission frame, in addition to the reception intensity data, ID information that is different for each transmitter is stored, and reception is performed. In the machine, when the second control unit determines which of the plurality of wheels the transmitter is attached to, the result indicating whether the transmitter is attached to the plurality of wheels and the transmission It is characterized by storing the ID information stored in the frame in association with each other.

In this way, ID information is also stored in the transmission frame in addition to the reception intensity data, and stored in the transmission frame and the wheel position detection result indicating which of the plurality of wheels the transmitter is attached on the receiver side. ID information thus recorded can be stored in association with each other. Thus, for example, when the wheel position detection device is applied to a tire air pressure detection device as shown in claim 20 , when transmitting a detection signal related to tire air pressure from the transmitter, ID information is also sent. Thus, the receiver can determine which wheel the detection signal related to the tire air pressure is based on the stored wheel position detection result and the ID information.

  In the invention according to claim 5, the trigger machine is disposed on the rear two wheels (6c, 6d) side with respect to the two front wheels (6a, 6b), and the right rear wheel (6c) constituting the two rear wheels. ) And the left rear wheel (6d), the first trigger machine (5a) disposed at different distances, and the right front wheel (6a) disposed on the two front wheels side of the rear wheels and constituting the two front wheels And the second trigger device (5b) arranged at different distances from the left front wheel (6b), and when the trigger signal is output from the first trigger device at the receiver, at least the rear When a transmission frame sent from a transmitter attached to two wheels is received and a trigger signal is output from the second trigger device, at least a transmission frame sent from a transmitter attached to the front two wheels is received. It is characterized by doing.

  In this way, two trigger machines are provided as a first trigger machine and a second trigger machine, each receiving a transmission frame sent from a transmitter mainly attached to the rear wheel, and one attached mainly to the front wheel side. The transmission frame sent from the transmitter can be received.

  The invention according to claim 6 is characterized in that both the first trigger machine and the second trigger machine are arranged offset in the same direction with respect to a center line that divides the vehicle body symmetrically. When such an offset arrangement is adopted, for example, as shown in claim 7, when a trigger signal is output from the first trigger device, it is based on received signal data stored in a transmission frame sent from the transmitter. Thus, the wheel (6d) closer to the first trigger machine among the two rear wheels can be identified. Further, when a trigger signal is output from the second trigger machine, based on the received signal data stored in the transmission frame sent from the transmitter, the wheel (6b) closer to the second trigger machine among the two front wheels. Can be identified. When the trigger signal is output from the first trigger machine, the received signal data stored in the transmission frame sent from the transmitter and the transmission sent from the transmitter when the trigger signal is output from the second trigger machine Based on both the received signal data stored in the frame, the wheel (6c) far from the first trigger machine in the two rear wheels and the wheel (6a) far from the second trigger machine in the two front wheels are specified. it can. This makes it possible to specify whether the transmitter is attached to two front wheels or two rear wheels.

  In this way, the wheel (6d) on the side closer to the first trigger machine among the two rear wheels can be identified by the reception intensity of the trigger signal of the first trigger machine, and the trigger signal reception intensity of the second trigger machine Of the two front wheels, the wheel (6b) closer to the second trigger machine can be identified.

  As a result, the transmitter attached to the second and third nearest wheels from the first trigger machine is connected to the second and third nearest wheels from the first trigger machine only by the reception intensity of the trigger signal of the first trigger machine. Even if it is difficult to specify which one is attached, it is possible to accurately specify it by using the reception intensity of the trigger signal of the second trigger machine. Therefore, it is possible to accurately specify whether each transmitter is attached to two front wheels or two rear wheels.

  In this case, even if the trigger signals of the first trigger machine and the second trigger machine can be received by the transmitters attached to three of the four wheels, respectively, the same means as the above means is used. It becomes possible to do. Therefore, similarly to the above, it is possible to accurately specify whether each transmitter is attached to the left or right of the two front wheels, or further to the left or right of the two rear wheels.

  In the invention according to claim 8, the trigger machine is disposed on the left two wheels (6b, 6d) side with respect to the right two wheels (6a, 6c) and the left front wheel (6b) constituting the left two wheels and the left The first trigger machine (5a) arranged at a different distance from the rear wheel (6d), the right front wheel (6a) and the right rear wheel arranged on the right two wheels side of the two left wheels and constituting the two right wheels (6c) and a second trigger machine (5b) arranged at different distances. When the trigger signal is output from the first trigger machine at the receiver, at least the left two wheels When a transmission frame sent from an attached transmitter is received and a trigger signal is output from the second trigger machine, at least a transmission frame sent from a transmitter attached to the right two wheels is received. It is said.

  In this way, two trigger machines are provided as a first trigger machine and a second trigger machine, each receiving a transmission frame sent from a transmitter mainly attached to the left wheel, and mainly attached to the right wheel. The transmission frame sent from the transmitter can be received.

  The invention according to claim 9 is characterized in that both the first trigger machine and the second trigger machine are arranged offset in the same direction with respect to a center line that divides the vehicle body in a longitudinally symmetrical manner. When such an offset arrangement is adopted, for example, as shown in claim 10, when a trigger signal is output from the first trigger device, the received signal data stored in the transmission frame transmitted from the transmitter is included. Based on the left two wheels, the wheel (6d) closer to the first trigger machine can be identified. Further, when a trigger signal is output from the second trigger machine, based on the received signal data stored in the transmission frame sent from the transmitter, the wheel (6c) closer to the second trigger machine among the two right wheels Can be identified. Further, when a trigger signal is output from the first trigger machine, received signal data stored in a transmission frame sent from the transmitter and a transmission sent from the transmitter when a trigger signal is output from the second trigger machine Based on the received signal data stored in the frame, the wheel (6b) on the far side from the first trigger machine among the two left wheels and the wheel (6a) on the far side from the second trigger machine in the two right wheels can be specified. . Thereby, it becomes possible to specify whether the transmitter is attached to the left two wheels or the right two wheels.

  Thus, the wheel (6d) on the side closer to the first trigger machine can be specified from the left two wheels by the reception intensity of the trigger signal of the first trigger machine, and the right side is determined by the reception intensity of the trigger signal of the second trigger machine. Of the two wheels, the wheel (6c) closer to the second trigger machine can be identified.

  As a result, the transmitter attached to the second and third nearest wheels from the first trigger machine is connected to the second and third nearest wheels from the first trigger machine only by the reception intensity of the trigger signal of the first trigger machine. Even if it is difficult to specify which one is attached, it is possible to accurately specify it by using the reception intensity of the trigger signal of the second trigger machine. Therefore, it is possible to accurately specify whether each transmitter is attached to the left two wheels or the right two wheels.

  Even in this case, the trigger signal of the first trigger machine and the second trigger machine can be received by the transmitters attached to three of the four wheels, respectively. It becomes possible to specify by means. Therefore, similarly to the above, it is possible to accurately specify whether each transmitter is attached to the left or right of the two front wheels, or further to the left or right of the two rear wheels.

  The invention described in claim 11 is characterized in that transmitters attached to a plurality of wheels are configured to transmit transmission frames at different transmission timings when receiving a trigger signal.

  Thus, by making the transmission timing of the transmission frame different in each transmitter, each transmission frame can be reliably received by the receiver.

  For example, when a trigger signal is received by a transmitter having a plurality of wheels attached thereto, the transmission timing can be determined according to the reception intensity of the trigger signal.

  Further, as shown in claim 13, when a trigger signal is received by a transmitter having a plurality of wheels attached thereto, the transmission timing can be determined at random every time the trigger signal is received.

  In the invention described in claim 14, the transmitter (2) includes a trigger device (5) for outputting a trigger signal on the vehicle body (7) side, and is provided to each of the plurality of wheels (6a to 6d) including tires. ), The trigger signal is received, the reception intensity of the trigger signal is obtained, the transmission timing of the transmission frame is determined according to the obtained reception intensity, and the transmission frame is provided on the vehicle body side at the transmission timing. Send to (3). Then, the receiver is characterized in that it determines which of the plurality of wheels the transmitter is attached to based on the transmission timing at which the transmission frame is sent.

  In this way, if each transmission frame is sent at a transmission timing corresponding to the reception intensity, the transmission frame is attached to any of the plurality of wheels by checking the transmission timing on the receiver side. It is possible to specify whether the transmission is from the transmitter. Thereby, it can be set as the wheel position detection apparatus which can detect to which wheel each transmitter is attached, without reading ID information by a user.

  In the invention according to claim 15, the trigger machine is arranged at a location at a different distance from each of the plurality of wheels, and the second controller stores in advance the relationship between the transmission timing and the reception intensity, It is characterized by discriminating which of the plurality of wheels the transmitter is attached to from the contents.

  In this way, if the trigger machine is arranged at a different distance from each of the plurality of wheels, the reception intensity of the trigger signal at each transmitter is all different. For this reason, the transmission timings of the transmission frames of the transmitters are all different, and it is possible to determine which of the plurality of wheels the transmitter is attached to.

  In this case, as shown in claim 16, the trigger device outputs a trigger signal having a signal strength that cannot be received by a transmitter mounted on a wheel farthest from the trigger device among a plurality of wheels. In the receiver, in the receiver, in the second control unit, the transmitter to which no transmission frame has been sent is attached to the wheel farthest from the trigger machine among the plurality of wheels. Can be determined.

The seventeenth to nineteenth aspects combine the features of the second, fourth , fifth, and eighth aspects with the invention according to the fourteenth aspect. Thereby, the same effects as those in the above claims can be obtained.

  In these first to nineteenth aspects, the present invention is shown as a wheel position detecting device. However, as shown in a twentyth aspect, the wheel position detecting device can be incorporated in a tire air pressure detecting 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 transmitter 2, a receiver 3, a display 4, and a trigger device 5.

  As shown in FIG. 1, the transmitter 2 is attached to each wheel 6 a to 6 d in the vehicle 1, detects the air pressure of the tire attached to the wheels 6 a to 6 d, and a detection signal indicating the detection result. Is stored in a transmission frame and transmitted. The receiver 3 is attached to the vehicle body 7 side of the vehicle 1 and receives a transmission frame transmitted from the transmitter 2 and performs various processes and calculations based on the detection signal stored therein. By doing so, the tire pressure is obtained. 2A and 2B show block configurations of the transmitter 2 and the receiver 3.

  As shown in FIG. 2A, the transmitter 2 includes a sensing unit 21, a microcomputer 22, a battery 23, a transmission antenna 24, and a reception antenna 25.

  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 microcomputer 22 is a well-known one including a control unit (first control unit) 22a, a transmission unit 22b, a reception unit 22c, and the like, and according to a program stored in a memory (not shown) in the control unit 22a. A predetermined process is executed.

  The control unit 22a receives the detection signal related to the tire pressure from the sensing unit 21, processes the signal and processes it as necessary, and transmits each transmitter 2 as data indicating the detection result (hereinafter referred to as tire pressure data). The ID information is stored in the transmission frame, and then the transmission frame is sent to the transmission unit 22b. The process of sending a signal to the transmitter 22b is executed at predetermined intervals according to the program.

  The control unit 22a receives the trigger signal from the trigger device 5 through the reception antenna 25 and the reception unit 22c, and obtains the trigger signal reception intensity by performing signal processing on the trigger signal, and processes the trigger signal as necessary. Is received in a transmission frame in which data relating to tire air pressure is stored, or in a transmission frame different from that, and then the transmission frame is sent to the transmission unit 22b. The process of sending a signal to the transmitter 22b is also performed according to the program.

  For example, the transmission timing of how many seconds after receiving the trigger signal to send the transmission frame is set differently for each transmitter 2 in advance. For this reason, transmission frames are transmitted at different timings from the transmitters 2 of the wheels 6a to 6d.

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

  Moreover, you may set the program memorize | stored in the control part 22a 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 transmitters 2 all different with a high probability.

  The transmission unit 22 b functions as an output unit that transmits the transmission frame transmitted from the control unit 22 a to the receiver 3 through the transmission antenna 24.

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

  The battery 23 supplies power to the control unit 22a and the like, and receives power supply from the battery 23, collects data related to tire pressure in the sensing unit 21, and performs various calculations in the control unit 22a. Is executed.

  The transmitter 2 configured in this way is attached to an air injection valve in each of the wheels 6a to 6d, for example, and is arranged so that the sensing unit 21 is exposed inside the tire. Accordingly, the corresponding tire pressure is detected, and a transmission frame is transmitted at predetermined intervals (for example, every minute) through the transmission antenna 24 provided in each transmitter 2.

  As shown in FIG. 2B, the receiver 3 has an antenna 31 and a microcomputer 32.

  The antenna 31 is one or two common antennas that collectively receive transmission frames transmitted from the transmitters 2, and is fixed to the vehicle body 7.

  The microcomputer 32 is a well-known one having a receiving unit 32a, a control unit (second control unit) 32b, and the like, and performs predetermined processing according to a program stored in a memory (not shown) in the control unit 32b. Execute.

  The receiving unit 32a functions as an input unit that receives a transmission frame from each transmitter 2 received by each antenna 31 and sends the transmission frame to the control unit 32b.

  The control unit 32b outputs a trigger command signal that instructs the trigger device 5 to output a trigger signal, receives the transmission frame transmitted from the reception unit 32a, and stores each transmitter stored in the transmission frame. Based on the received intensity data of the trigger signal at 2, wheel position detection is performed to identify which transmitted frame is from the transmitter 2 attached to any of the wheels 6a to 6d. This wheel position detection method will be described later in detail.

  Further, the control unit 32b obtains the tire air pressure by performing various signal processing and calculation based on the data indicating the detection result stored in the received transmission frame, and displays an electric signal corresponding to the obtained tire air pressure. To the device 4. For example, the control unit 32b 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. Thereby, the indicator 4 is informed that the tire pressure of any of the wheels 6a to 6d 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 32 b 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 32b of the receiver 3 is input, the trigger device 5 outputs a trigger signal having a predetermined signal strength. The trigger machine 5 is disposed at a position that is different from all four wheels 6a to 6d, and is disposed in the vicinity of the left rear wheel 6d in the present embodiment. For this reason, the distance from the trigger machine 5 to each wheel 6a-6d becomes long in order of the left rear wheel 6d, the right rear wheel 6c, the left front wheel 6b, and the right front wheel 6a in order.

  The trigger machine 5 may be mounted anywhere as long as the surrounding area is 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. Moreover, since it is preferable that the trigger machine 5 is disposed at a position where the difference in distance from the trigger machine 5 to each of the wheels 6a to 6d becomes large, for example, the rear wheels 6c and 6d and the front wheels 6a and 6b It should be placed in front.

  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 configured as described above will be described.

  First, when an ignition switch (not shown) is switched from OFF to ON, the control unit 32b of the receiver 3 is turned on. After a predetermined time has elapsed since the power was turned on, the control unit of the receiver 3 is used for wheel position detection. A trigger command signal is output from 32 b to the trigger machine 5. When this trigger command signal is input to the trigger machine 5, the trigger machine 5 generates a trigger signal having a predetermined signal intensity toward each transmitter 2. When this trigger signal is input to the control unit 22a through the reception antenna 25 and the reception unit 22c of each transmitter 2, the control unit 22a enters the Wake-up state and measures the reception intensity of the received trigger signal.

  Here, it is known that the signal intensity of the trigger signal attenuates according to the distance. For example, in free space, the attenuation characteristic depending on the distance of the signal intensity of the trigger signal is expressed as shown in FIG. When this characteristic is compared with the relationship of the distance from the trigger device 5 of the present embodiment to the transmitter 2 attached to each of the wheels 6a to 6d, for example, the relationship of FIG. 4 is obtained.

  That is, as described above, since the distance from the trigger machine 5 is longer in the order of the left rear wheel 6d, the right rear wheel 6c, the left front wheel 6b, and the right front wheel 6a, the transmission attached to each wheel 6a to 6d. The reception intensity of the trigger signal when received by the machine 2 decreases in the order of the left rear wheel 6d, the right rear wheel 6c, the left front wheel 6b, and the right front wheel 6a.

  Further, when each transmitter 2 obtains the reception intensity of the trigger signal, it stores it in a transmission frame together with the ID information of each transmitter 2 and outputs from the transmitter 2. At this time, since the transmission timing of the transmission frame from each transmitter 2 is different, the transmission frame transmitted from each transmitter 2 is reliably received by the receiver 3 without interference. it can.

  When the transmission frame transmitted from each transmitter 2 is received by the receiver 3, the control unit 32b reads the ID information and the reception intensity data of each transmitter 2 stored in the transmission frame. The ID information is arranged in the order of reception intensity. Thus, the highest received intensity is the transmission frame from the transmitter 2 attached to the left rear wheel 6d, the second highest is the transmission frame from the transmitter 2 attached to the right rear wheel 6c, the third The lowest frame is determined as the transmission frame from the transmitter 2 attached to the left front wheel 6b, and the lowest frame is determined as the transmission frame from the transmitter 2 attached to the right front wheel 6a.

  FIG. 5 shows a flow when determining which of the wheels 6a to 6d each transmitter 2 is attached to. As shown in this figure, when the four transmitters 2 are represented as transmitters A to D, when a trigger signal is output from the trigger unit 5, it is received by each transmitter A to D. Is done. Thus, the reception intensity data of the trigger signal is stored in the transmission frame together with the ID information: A to D from each transmitter A to D, and is transmitted to the receiver 3.

  At this time, for example, as shown in FIG. 6, transmission frames are sent in order according to the reception intensity of the trigger signal. For this reason, the transmission timing from each transmitter 2 can be prevented from overlapping, and all the transmission frames are reliably received by the receiver 3.

  When all the transmission frames are received, the control unit 32b of the receiver 3 arranges the data stored in each transmission frame in the order of reception intensity. In this order, each transmission frame includes the left rear wheel 6d and the right It is specified that the signal is transmitted from the transmitter 2 attached to the rear wheel 6c, the left front wheel 6b, and the right front wheel 6a.

  In this way, it is possible to specify from the reception intensity data stored in each transmission frame whether the transmission frame is transmitted from the transmitter 2 attached to any of the wheels 6a to 6d. . Thereafter, the control unit 32b of the receiver 3 stores (registers) the ID information stored in each transmission frame in association with the wheels 6a to 6d to which the transmitter 2 is attached. Thus, when the tire pressure detection described below is performed, the receiver 3 transmits the transmission frame storing the data related to the tire pressure from the ID information stored in the transmission frame. It is possible to determine which of the wheels 6a to 6d the transmitter 2 that sent the frame is attached to, and obtain the tire air pressure of each of the wheels 6a to 6d.

  Next, when the regular transmission mode is set and normal tire pressure detection is performed, as described above, each transmitter 2 indicates the tire pressure from the sensing unit 21 or the temperature in the tire to the control unit 22a. A detection signal is input. The detection signal is processed as necessary to obtain tire pressure data, which is stored in the transmission frame together with the ID information of each transmitter 2 and then transmitted to the receiver 3 through the transmitter 22b every predetermined period. Sent to the side.

  On the other hand, when a transmission frame is transmitted from the transmitter 2, it is received by the antenna 31 of the receiver 3 and input to the control unit 32b through the reception unit 32a. Then, in the control unit 32b, data indicating the tire pressure and data indicating the temperature in the tire are extracted from the transmission 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 ID information is stored in the transmission frame, it is compared with the ID information stored at the time of detecting the wheel position, and the transmission frame is transmitted from the transmitter 2 attached to any of the wheels 6a to 6d. It is determined whether it has been received.

  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 lower than a predetermined threshold value, a signal indicating that is output from the control unit 32b to the display unit 4, and the tire pressure has decreased. It is displayed on the display 4 in a form that can identify any of ˜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 32b of the receiver 3 to the trigger unit 5 again, and a trigger signal is output from the trigger unit 5. When this trigger signal is input to the control unit 22a through the reception antenna 25 and the reception unit 22c, the transmitter 2 is switched to the Sleep state, and the wheel position detection and tire pressure detection processing is completed.

  As described above, in the tire air pressure detection device of the present embodiment, the distance from the trigger machine 5 to each transmitter 2 is different, and based on the reception intensity of the trigger signal at each transmitter 2. The transmitter 2 is specified to which of the wheels 6a to 6d. Specifically, it is specified from the reception intensity data stored in each transmission frame whether the transmission frame is transmitted from the transmitter 2 attached to any of the wheels 6a to 6d. Thereby, wheel position detection can be performed accurately.

  Moreover, according to such a transmitter 2, while being able to make all the transmitters 2 the same structure, transmitter 2 itself is attached to which wheel 6a-6d with respect to each transmitter 2. Since it is not necessary to perform a process for setting ID information indicating whether or not, it is possible to reduce the number of setting processes of the tire air pressure detection device.

  In particular, as in the present embodiment, when the antenna 31 of the receiver 3 is used as a common antenna that collectively receives transmission frames from the transmitters 2, a plurality of transmission frames are transmitted to one antenna 31. Will be. For this reason, it is difficult to determine which transmission frame is transmitted from the transmitter 2 attached to which wheel 6a to 6d. Therefore, it is particularly effective to specify the wheels 6a to 6d to which the transmitter 2 is attached according to the reception intensity of the trigger signal as in the present embodiment.

  Here, the ID information is stored in both the transmission frame that stores the reception intensity data of the trigger signal and the transmission frame that stores the data related to the tire pressure, and the wheel to which each transmitter 2 is attached based on the reception intensity data. ID information is stored when 6a to 6d are specified, and thereafter, a transmission frame storing data related to tire air pressure based on the ID information is sent from the transmitter 2 attached to any of the wheels 6a to 6d. I try to determine if it is a thing.

  However, ID information is not necessarily used. That is, when transmitting a transmission frame storing data related to tire air pressure from the transmitter 2, the reception intensity data when the trigger signal is received is stored in the transmission frame every time, and the transmission frame is transmitted from the reception intensity data to the wheel 6a. It is also possible to determine which of the transmitters 2 to 6d is sent.

(Second Embodiment)
A second embodiment of the present invention will be described. The present embodiment is different from the first embodiment in that only one of the four wheels 6a to 6d to which the transmitter 2 is attached when the signal intensity of the trigger signal that can be output by the trigger machine 5 is limited. On the assumption that the transmitter 2 does not need to receive the trigger signal, each transmitter 2 finally has four wheels 6a to 6 on the basis of the received intensity data sent from the remaining transmitters 2 that can be received. It is specified which of 6d is attached. Note that the overall configuration of the tire air pressure detection device is the same as that of the first embodiment, and therefore only the portions that are different from the first embodiment will be described.

  As described above, it is assumed that there is a limit to the signal intensity of the trigger signal that can be output by the trigger machine 5. For example, since the usable radio wave is restricted by laws and regulations, the trigger signal may not be transmitted to the transmitters 2 attached to all the wheels 6a to 6d. For example, the relationship between the distance from the trigger device 5 and the signal strength of the trigger signal and the lower limit of reception strength (reception sensitivity) that can be received by the transmitter 2 may be as shown in FIG.

  In such a case, only the transmitter 2 that can receive the trigger signal is stored in the transmission frame together with the ID information, as in the first embodiment. It is sent to the receiver 3.

  FIG. 8 shows the flow when determining which of the wheels 6a to 6d each transmitter 2 is attached to when the signal intensity of the trigger signal is limited. As shown in this figure, when four transmitters 2 are represented as transmitters A to D, and the trigger signals can be received by three of the transmitters B to D, the trigger signal from the trigger unit 5 Is output by each of the transmitters B to D, and is not received by the transmitter A. For this reason, the reception intensity data of the trigger signal is stored in the transmission frame together with the ID information: B to D from each transmitter B to D, and is transmitted to the receiver 3, and with respect to the transmitter A, the transmission frame is transmitted to the receiver 3. It will not be possible.

  When the transmission frames sent from the three transmitters B to D are received, the control unit 32b of the receiver 3 arranges the data stored in the transmission frames in the order of reception intensity. On the other hand, for detection of tire pressure, a transmission frame storing data related to tire pressure is delivered to the receiver 3 from all of the transmitters A to D at predetermined intervals. For this reason, the transmission frames sent from the transmitters B to C are received by the receiver 3 at the time of tire pressure detection at predetermined intervals in addition to the wheel position detection, and are sent from the transmitter A. The transmission frame is received only when the tire pressure is detected.

  Therefore, based on the data previously arranged in the order of reception intensity and the data stored in the transmission frame received only when the tire pressure is detected, each transmitter 2 is attached to any of the wheels 6a to 6d. Is identified. Specifically, the transmission frame in which the reception intensity data is stored is specified as being transmitted from the transmitter 2 attached to the left rear wheel 6d, the right rear wheel 6c, and the left front wheel 6b in the order of reception intensity. The transmission frame received only when the tire pressure is detected is specified as being transmitted from the transmitter 2 attached to the right front wheel 6a.

  In this way, it is possible to specify from the reception intensity data stored in each transmission frame whether the transmission frame is transmitted from the transmitter 2 attached to any of the wheels 6a to 6d. . Even if it does in this way, the effect similar to 1st Embodiment is acquired.

  Here, regarding the transmitter 2 attached to the wheel farthest from the trigger machine 5 to which the reception intensity data has not been sent, when a transmission frame storing data related to tire pressure is sent, It has been described that wheel position detection is performed. However, since the number of wheels is known to be four in advance, when a transmission frame in which reception intensity data is stored is sent from the other three transmitters 2, the transmitter 2 has not been sent as it is. Can be specified as being attached to the wheel farthest from the trigger machine 5.

  In this case, since the trigger signal cannot be received by the transmitters 2 of all the wheels 6a to 6d, an instruction to switch between the Wake-up state and the Sleep state can be issued based on the trigger signal. become unable. Therefore, it is preferable to switch between the Wake-up state and the Sleep state based on detection of tire rotation by a motion sensor such as a constant periodic transmission method or an acceleration sensor.

(Third embodiment)
A third embodiment of the present invention will be described. FIG. 9 is a block diagram illustrating an overall configuration of a tire air pressure detection device to which the wheel position detection device according to the present embodiment is applied. This embodiment is different from the first and second embodiments in that the trigger machine 5 is two of the first trigger machine 5a and the second trigger machine 5b with respect to the first embodiment. Since the points are the same as those in the first and second embodiments, only different parts will be described. This embodiment also assumes a case where the trigger signal can be received by only three of the four wheels 6a to 6d due to legal restrictions and the like.

  As shown in FIG. 9, the trigger machine 5 is a first trigger machine 5a and a second trigger machine 5b, and the first trigger machine 5a is installed at the same place as in the first embodiment shown in FIG. Yes.

  The 2nd trigger machine 5b is offset and arranged in the same direction as the 1st trigger machine 5a with respect to the central line which divides vehicles 1 symmetrically. Similarly to the first trigger machine 5a, the second trigger machine 5b is also arranged at a position at a different distance from all four wheels 6a to 6d. In the present embodiment, the second trigger machine 5b is arranged in the vicinity of the left front wheel 6b. For this reason, the distance from the 2nd trigger machine 5b to each wheel 6a-6d becomes long in order of the left front wheel 6b, the right front wheel 6a, the left rear wheel 6d, and the right rear wheel 6c in order.

  When wheel position detection is performed using the first and second trigger machines 5a and 5b configured as described above, first, one of the first and second trigger machines 5a and 5b from the receiver 3, for example, the first trigger machine 5a and 5b is used. A trigger command signal is output to the 1 trigger machine 5a, and a trigger signal is output from the 1st trigger machine 5a.

  As a result, the trigger signal is received by each transmitter 2, but the reception intensity is different as in the first and second embodiments. That is, the reception intensity of the trigger signal when received by the transmitter 2 attached to each of the wheels 6a to 6d decreases in the order of the left rear wheel 6d, the right rear wheel 6c, and the left front wheel 6b, and the first trigger machine 5a. The trigger signal is not received by the transmitter 2 of the right front wheel 6a farthest from the transmitter. Of course, the trigger signal may be received by the transmitter 2 of the right front wheel 6a depending on the surrounding environment or the like, but it is considered that the basic trigger signal is not received. For this reason, different reception intensity data is included in the transmission frame transmitted by each transmitter 2 other than the right front wheel 6a.

  At this time, although the distance from the first trigger device 5a to each transmitter 2 is different, the difference in the distance from the transmitter 2 attached to the right rear wheel 6c and the left front wheel 6b is very large. Absent. For this reason, the difference in the reception intensity of the trigger signals received by these transmitters 2 is not so large, and the transmitter that has sent the transmission frame only by detecting the wheel position using the trigger signal from the first trigger device 5a. It may be difficult to specify whether 2 is attached to the right rear wheel 6c or the left front wheel 6b.

  For this reason, in the present embodiment, a trigger command signal is further output from the receiver 3 to the other of the first and second trigger devices 5a and 5b, for example, the second trigger device 5b, and from the second trigger device 5b. Outputs a trigger signal.

  As a result, the trigger signal is received by each transmitter 2, but the second trigger device 5b is installed at a different location from the first trigger device 5a, and thus received by each transmitter 2. The reception intensity of the trigger signal is different from that in the first and second embodiments. That is, the reception intensity of the trigger signal when it is received by the transmitter 2 attached to each of the wheels 6a to 6d decreases in the order of the left front wheel 6b, the right front wheel 6a, and the left rear wheel 6d. The transmitter 2 of the farthest right rear wheel 6c does not receive the trigger signal. Also in this case, the trigger signal may be received by the transmitter 2 of the right rear wheel 6c depending on the surrounding environment or the like, but it is considered that the basic trigger signal is not received.

  Therefore, the reception intensity of the trigger signal received by each receiver 3 is different between the case of the first trigger machine 5a and the case of the second trigger machine 5b.

  For this reason, first, in the case of the first trigger device 5a, the transmitter 2 that has transmitted the transmission frame including the highest reception strength data transmits the transmission frame including the left rear wheel 6d, the second and third highest reception strength data. Is identified as the right rear wheel 6c or the left front wheel 6b.

  Subsequently, in the case of the second trigger device 5b, the transmitter 2 that has transmitted the transmission frame including the highest reception strength data transmits the transmission frame including the left front wheel 6b, the second and third highest reception strength data. The transmitter 2 is identified as the right front wheel 6a or the left rear wheel 6d.

  To summarize these results, in the case of the first trigger machine 5a, the transmitter 2 that has sent a transmission frame including the second and third highest received intensity data sends either the right rear wheel 6c or the left front wheel 6b. Even if it cannot be specified, in the case of the second trigger machine 5b, it can be specified that the transmitter 2 that has transmitted the transmission frame including the highest received intensity data is attached to the left front wheel 6b. The rear wheel 6c can be specified. Further, from the opposite view, the right front wheel 6a can be finally identified.

  FIGS. 10A and 10B are diagrams showing the relationship between the distance from the first and second trigger devices 5a and 5b and the signal strength of the trigger signal and the reception sensitivity of the transmitter 2, respectively. is there. As shown in these drawings, when a trigger signal is output from the first trigger device 5a, the transmitter 2 attached to the left rear wheel 6d, the right rear wheel 6c, and the left front wheel 6b receives the trigger signal. When a trigger signal is output from the second trigger device 5b, it is assumed that the transmitter 2 attached to the left front wheel 6b, the right front wheel 6a, and the left rear wheel 6d can receive the trigger signal. .

  In this case, FIG. 11 shows a flow when determining which of the wheels 6a to 6d each transmitter 2 is attached to.

  First, a trigger signal is output from the first trigger machine 5a. At this time, when the four transmitters 2 are represented as transmitters A to D, it is assumed that the trigger signals can be received by the three transmitters A, C, and D, but cannot be received by the transmitter B. In this case, the ID information: A, C, D from each transmitter A, C, D together with the received signal strength data of the trigger signal is stored in the transmission frame and transmitted to the receiver 3, and the transmitter B receives the transmission frame. It will not be transmitted to machine 3.

  Subsequently, a trigger signal is output from the second trigger machine 5b. At this time, it is assumed that the trigger signals can be received by the three transmitters A to C and cannot be received by the transmitter D. In this case, the ID information: A to C and the received intensity data of the trigger signal are stored in the transmission frame and transmitted to the receiver 3 from each transmitter A to C, and the transmission frame is transmitted to the receiver 3 regarding the transmitter D. It will not be possible.

  Therefore, based on the reception intensity data stored in the transmission frame from each transmitter 2 sent to the receiver 3, first, the transmitter having the highest reception intensity of the trigger signal of the first trigger machine 5a. C is identified as being attached to the left rear wheel 6d, and the remaining two transmitters A and D are identified as the right rear wheel 6c or the left front wheel 6b. Then, the transmitter A having the highest trigger signal reception intensity of the second trigger device 5b is identified as being attached to the left front wheel 6b, and the remaining two transmitters B and C are connected to the right front wheel 6a or the left It is identified as the rear wheel 6d. At this time, since it is specified that the transmitter C is already attached to the left rear wheel 6d, it can be specified that the transmitter B is attached to the right front wheel 6a. Thereby, it can be specified that the transmitter D is finally attached to the right rear wheel 6c.

As described above, according to the tire pressure detection device of the present embodiment, the first trigger device 5a and the second trigger device 5b are installed as the trigger device 5, and the first and second trigger devices 5a and 5b are installed. Identify which transmitter 2 is attached to each of the wheels 6a to 6d by using the fact that the reception intensity when each trigger signal is received by each transmitter 2 is different. It becomes possible to do.

  Thereby, it becomes possible to specify to which of the wheels 6a to 6d the transmitter 2 is attached more accurately than in the first and second embodiments.

  In the present embodiment, it is assumed that the trigger signal from one trigger machine can be received by only three of the four wheels. However, if the trigger signal can be received by only two wheels, each transmitter 2 can be simply and accurately. Can be specified. However, it is assumed that the number of rings that can receive the trigger signal increases depending on the surrounding environment. For this reason, the trigger signal output intensity or the trigger reception sensitivity of the transmitter 2 is set so that the trigger can be received by only two wheels at normal times, and the trigger signal can be received by three wheels due to environmental changes. Even in the case of being stuck, it is preferable to take the form shown in the present embodiment in order to prevent a specific error in position.

(Fourth embodiment)
A fourth embodiment of the present invention will be described. The present embodiment does not send a transmission frame in which reception intensity data is stored to the receiver 3, but uses each transmitter 2 according to the transmission timing of the transmission frame set according to the reception intensity of the trigger signal. 2 is used to specify which of the wheels 6a to 6d is attached. Note that the overall configuration of the tire air pressure detection device is the same as that of the first embodiment, and therefore only the portions that are different from the first embodiment will be described.

  The control unit 22a of each transmitter 2 stores a transmission timing calculation program. With this program, when the trigger signal is received from the trigger device 5, the reception strength of the trigger signal is obtained, and the transmission timing of the transmission frame by each transmitter 2 is obtained in accordance with the reception strength. 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 stored in the control unit 22a.

  For this reason, the transmission timing of each transmitter 2 is inevitably different due to the difference in reception intensity, and each transmitter 2 is attached to any of the wheels 6a to 6d by the receiver 3 based on the difference in transmission timing. It is possible to detect the wheel position as to whether it is a thing. The control unit 32b of the receiver 3 also stores the relationship between the trigger signal reception intensity and the transmission timing. This relationship may be simply a correspondence relationship between the order in which the transmission frames are received and the wheels 6a to 6d to which each transmitter 2 is attached, or an arithmetic expression itself used for setting the transmission timing with respect to the reception intensity of the trigger signal. It may be. In the former case, it is possible to uniquely identify which of the wheels 6a to 6d each transmitter 2 is attached to in the order in which the transmission frames are received. In the latter case, for example, using the time taken from the output of the trigger command signal to the trigger device 5 until the reception of the transmission frame, the function equation used for setting the transmission timing for the reception intensity of the trigger signal is used. The reception intensity is calculated backward, and from the result, it can be specified which of the wheels 6a to 6d each transmitter 2 is attached to.

  As described above, even if the reception strength data is not stored in the transmission frame and sent to the receiver 3, if the transmission timing of the transmission frame is made different according to the reception strength of the trigger signal, the transmission timing can be determined. It is possible to specify which of the wheels 6a to 6d each transmitter 2 is attached to.

(Other embodiments)
In the above-described embodiment, the antenna 31 is described as one common antenna. However, four antennas may be provided corresponding to the wheels 6a to 6d. However, when the antenna 31 is a common antenna, it is particularly difficult to specify the wheels 6a to 6d to which the transmitter 2 is attached. Therefore, it is effective to apply the present invention to a shared antenna. .

  Moreover, in the said 3rd Embodiment, although the 2nd trigger machine 5b was arrange | positioned in the vicinity of the left front wheel 6b, it is also possible to arrange | position in the vicinity of the right rear wheel 6c. That is, the first and second trigger machines 5a and 5b can be offset in the same direction with respect to the center line that divides the vehicle body 7 in the longitudinal direction. Even if it does in this way, it will become possible to perform the wheel position detection similar to 3rd Embodiment.

  In the present specification, the ID information means ID information that is given as different for each of the wheels 6a to 6d that is attached to distinguish each of the wheels 6a to 6d. It does not mean ID information for distinguishing whether the transmission frame to be transmitted is that of the host vehicle or the other vehicle. In other words, the present invention does not exclude the case where ID information for distinguishing whether the transmission frame transmitted from the transmitter 2 belongs to the own vehicle or the other vehicle is stored in the transmission frame. Absent. Even if such ID information is included, according to the present invention, the ID information attached as different for each of the wheels 6a to 6d can be eliminated, and the position of the wheel can be changed like tire rotation. However, the problem that ID information must be re-registered in the receiver 3 can be solved.

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 and receiver of the tire pressure detection apparatus shown in FIG. It is the graph which showed the attenuation characteristic by the distance of the signal strength of the trigger signal in free space. It is the figure which showed the relationship between the attenuation characteristic shown in FIG. 3, and the distance from the trigger machine 5 to the transmitter 2 attached to each wheel 6a-6d. It is the schematic diagram which showed the flow when discriminate | determining to which of each wheel 6a-6d each transmitter 2 was attached. 5 is a timing chart showing the relationship between the trigger signal and the transmission timing of the transmission frame from each transmitter 2. It is the figure which showed the relationship between the distance from the trigger machine 5, the signal strength of a trigger signal, and the receiving sensitivity of the transmitter 2. FIG. It is the schematic diagram which showed the flow when discriminate | determining to which of each wheel 6a-6d each transmitter 2 was attached when the signal strength of a trigger signal has a limit. It is a block diagram which shows the whole structure of the tire pressure detection apparatus with which the wheel position detection apparatus in 2nd Embodiment of this invention was applied. It is the figure which showed the relationship between the distance from the 1st, 2nd trigger machine 5a, 5b, the signal strength of a trigger signal, and the receiving sensitivity of the transmitter 2. FIG. It is the figure which showed the flow when discriminate | determining to which of each wheel 6a-6d each transmitter 2 was attached.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Transmitter, 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, 6e ... spare wheel, 7 ... vehicle body, 21 ... sensing unit, 22 ... microcomputer, 22a ... control unit, 22b ... transmission unit, 22c ... reception unit, 23 ... battery, 24 ... Transmission antenna, 25. Reception antenna, 31. Antenna, 32... Microcomputer, 32 a.

Claims (20)

Each of the plurality of wheels (6a to 6d) including tires is provided with a receiving unit (22c) that receives a trigger signal, and the reception intensity of the trigger signal received by the receiving unit and the received reception Transmitter having a first control unit (22a) for storing received intensity data representing strength in a transmission frame, and a transmission unit (22b) for transmitting the transmission frame processed by the first control unit (2) and
Body (7) provided with only one side, triggering device for outputting the trigger signal (5),
A receiving unit (32a) provided on the vehicle body side for receiving the transmission frame, the reception intensity represented by the reception intensity data stored in the transmission frame, and attached to each of the plurality of wheels from the trigger device A receiver (3) including a second control unit (32b) for determining which of the plurality of wheels the transmitter is attached to, based on the relationship with the distance to the transmitter, have,
The trigger machine is arranged at a different distance from each of the plurality of wheels,
The second control unit is configured such that the order in which the distance from the trigger machine to the transmitter attached to each of the plurality of wheels is close to the order in which the reception intensity is large matches the plurality of transmitters. A wheel position detecting device for determining which of the wheels is attached . In the transmitter, when the first control unit creates the transmission frame, in addition to the reception intensity data, ID information that is different in each transmitter is stored,
In the receiver, when the second control unit determines which of the plurality of wheels the transmitter is attached to, the transmitter is attached to any of the plurality of wheels. The wheel position detection device according to claim 1, wherein a result of whether or not the vehicle is stored and the ID information stored in the transmission frame are stored in association with each other. Each of the plurality of wheels (6a to 6d) including tires is provided with a receiving unit (22c) that receives a trigger signal, and the reception intensity of the trigger signal received by the receiving unit and the received reception Transmitter having a first control unit (22a) for storing received intensity data representing strength in a transmission frame, and a transmission unit (22b) for transmitting the transmission frame processed by the first control unit (2) and
A trigger machine (5) provided on the vehicle body (7) side and outputting the trigger signal;
A receiving unit (32a) provided on the vehicle body side for receiving the transmission frame, the reception intensity represented by the reception intensity data stored in the transmission frame, and attached to each of the plurality of wheels from the trigger device A receiver (3) including a second control unit (32b) for determining which of the plurality of wheels the transmitter is attached to, based on the relationship with the distance to the transmitter, Have
The trigger machine is disposed at a different distance from each of the plurality of wheels, and is received as the trigger signal by the transmitter attached to the wheel farthest from the trigger machine among the plurality of wheels. Outputs signal strength that is not possible,
The second control unit is configured such that the order in which the distance from the trigger machine to the transmitter attached to each of the plurality of wheels is close to the order in which the reception intensity is large matches the plurality of transmitters. It is determined which one of the wheels is attached, and the transmitter to which the transmission frame is not sent is attached to the wheel farthest from the trigger machine among the plurality of wheels. A wheel position detecting device characterized by determining that there is a wheel position. In the transmitter, when the first control unit creates the transmission frame, in addition to the reception intensity data, ID information that is different in each transmitter is stored,
In the receiver, when the second control unit determines which of the plurality of wheels the transmitter is attached to, the transmitter is attached to any of the plurality of wheels. The wheel position detection device according to claim 3 , wherein a result of whether or not the vehicle is stored and the ID information stored in the transmission frame are stored in association with each other. Each of the plurality of wheels (6a to 6d) including tires is provided with a receiving unit (22c) that receives a trigger signal, and the reception intensity of the trigger signal received by the receiving unit and the received reception Transmitter having a first control unit (22a) for storing received intensity data representing strength in a transmission frame, and a transmission unit (22b) for transmitting the transmission frame processed by the first control unit (2) and
A trigger machine (5) provided on the vehicle body (7) side and outputting the trigger signal;
A receiving unit (32a) provided on the vehicle body side for receiving the transmission frame, the reception intensity represented by the reception intensity data stored in the transmission frame, and attached to each of the plurality of wheels from the trigger device A receiver (3) including a second control unit (32b) for determining which of the plurality of wheels the transmitter is attached to, based on the relationship with the distance to the transmitter, Have
The plurality of wheels are two front wheels (6a, 6b) and two rear wheels (6c, 6d),
The trigger machine is arranged on the two rear wheels side with respect to the two front wheels and at a different distance from the right rear wheel (6c) and the left rear wheel (6d) constituting the two rear wheels. The first trigger device (5a) is disposed on the two front wheels side of the two rear wheels, and at a different distance from the right front wheel (6a) and the left front wheel (6b) constituting the two front wheels. A second trigger machine (5b),
In the receiver, when the trigger signal is output from the first trigger machine, at least the transmission frame sent from the transmitter attached to the two rear wheels is received and the second trigger is received. if the machine outputs the trigger signal, less also the vehicle wheel position detecting device you characterized by receiving the transmission frame sent from the attached the transmitter to the two front wheels. The plurality of wheels are two front wheels (6a, 6b) and two rear wheels (6c, 6d),
The trigger machine includes a first trigger machine (5a) disposed closer to the two rear wheels than the two front wheels, and a second trigger machine disposed closer to the two front wheels than the two rear wheels. (5b)
The second triggering device and the first triggering device are both either of claims 3 to 5, characterized in that it is arranged offset in the same direction with respect to the center line that divides the body into left-right symmetry The wheel position detection apparatus as described in any one. When the trigger signal is output from the first trigger machine, based on the received signal data stored in the transmission frame sent from the transmitter, the two rear wheels are close to the first trigger machine Identify the wheel (6d) on the side,
When the trigger signal is output from the second trigger machine, based on the received signal data stored in the transmission frame sent from the transmitter, the side closer to the second trigger machine among the two front wheels Identifying the wheel (6b)
When the trigger signal is output from the first trigger machine, the received signal data stored in the transmission frame sent from the transmitter, and when the trigger signal is output from the second trigger machine, Based on both of the received signal data stored in the transmission frame sent from the transmitter, the second wheel out of the two rear wheels from the first trigger device (6c) and the second out of the two front wheels. The wheel (6a) on the side far from the trigger machine is specified to specify which of the two front wheels and the two rear wheels the transmitter is attached to. Wheel position detector. Each of the plurality of wheels (6a to 6d) including tires is provided with a receiving unit (22c) that receives a trigger signal, and the reception intensity of the trigger signal received by the receiving unit and the received reception Transmitter having a first control unit (22a) for storing received intensity data representing strength in a transmission frame, and a transmission unit (22b) for transmitting the transmission frame processed by the first control unit (2) and
A trigger machine (5) provided on the vehicle body (7) side and outputting the trigger signal;
A receiving unit (32a) provided on the vehicle body side for receiving the transmission frame, the reception intensity represented by the reception intensity data stored in the transmission frame, and attached to each of the plurality of wheels from the trigger device A receiver (3) including a second control unit (32b) for determining which of the plurality of wheels the transmitter is attached to, based on the relationship with the distance to the transmitter, Have
The plurality of wheels are the right two wheels (6a, 6c) and the left two wheels (6b, 6d),
The trigger device is disposed on the left two wheels side of the right two wheels and is arranged at a different distance from the left front wheel (6b) and the left rear wheel (6d) constituting the left two wheels. A second vehicle (5a) and a second wheel disposed at a different distance from the right front wheel (6a) and the right rear wheel (6c), which are disposed on the right two wheels side of the left two wheels and constituting the right two wheels. A trigger machine (5b),
In the receiver, when the trigger signal is output from the first trigger machine, at least the transmission frame sent from the transmitter attached to the left two wheels is received, and the second trigger machine wherein when outputting a trigger signal, less also the vehicle wheel position detecting device you characterized by receiving the transmission frame sent from the attached the transmitter to the right 2 wheels from. The plurality of wheels are the right two wheels (6a, 6c) and the left two wheels (6b, 6d),
The trigger machine includes a first trigger machine (5a) disposed on the left two wheels side of the right two wheels and a second trigger machine (5b) disposed on the right two wheels side of the left two wheels. ), And
The first triggering device and the second triggering device are both claims 3, 4 and 8, characterized in that it is arranged offset in the same direction with respect to the center line that divides the vehicle body in the front-rear symmetry The wheel position detection apparatus as described in any one of these. When the trigger signal is output from the first trigger machine, a side closer to the first trigger machine among the two left wheels based on the received signal data stored in the transmission frame sent from the transmitter Identifying the wheel (6d)
When the trigger signal is output from the second trigger machine, based on the received signal data stored in the transmission frame sent from the transmitter, the side closer to the second trigger machine among the two right wheels Identifying the wheel (6c)
When the trigger signal is output from the first trigger machine, the received signal data stored in the transmission frame sent from the transmitter, and when the trigger signal is output from the second trigger machine, Based on the received signal data stored in the transmission frame sent from the transmitter, the wheel (6b) on the side farther from the first trigger machine out of the two left wheels and the second trigger on the two right wheels. The wheel according to claim 9, wherein the wheel (6a) on the side farther from the machine is specified to specify which of the left two wheels and the two right wheels is attached to the transmitter. Position detection device.   11. The transmitter according to claim 1, wherein the transmitters attached to the plurality of wheels are configured to transmit the transmission frame at different transmission timings when receiving the trigger signal. The wheel position detection apparatus as described in any one.   When the transmitter having the plurality of wheels attached thereto receives the trigger signal, the transmitter determines the transmission timing according to the reception intensity of the trigger signal and transmits the transmission frame. The wheel position detecting device according to claim 11.   The transmitter having the plurality of wheels attached thereto, when receiving the trigger signal, randomly determines the transmission timing each time the trigger signal is received, and transmits the transmission frame. The wheel position detecting device according to claim 11. Each of the plurality of wheels (6a to 6d) including tires is provided with a receiving unit (22c) that receives a trigger signal, and the reception intensity of the trigger signal received by the receiving unit and the received reception A first control unit (22a) that determines a transmission timing of a transmission frame according to intensity; and a transmission unit (22b) that transmits the transmission frame at the transmission timing determined by the first control unit. A transmitter (2)
A trigger machine (5) provided on the vehicle body (7) side and outputting the trigger signal;
The receiving unit (32a) provided on the vehicle body side for receiving the transmission frame, and which of the plurality of wheels the transmitter is attached to based on the transmission timing at which the transmission frame is transmitted And a receiver (3) provided with a second control unit (32b) for determining the wheel position detecting device. The trigger machine is arranged at a different distance from each of the plurality of wheels,
The second control unit stores in advance a relationship between the transmission timing and the reception intensity, and determines from the stored contents which of the plurality of wheels the transmitter is attached to. The wheel position detection device according to claim 14, wherein The trigger machine outputs, as the trigger signal, one having a signal intensity that cannot be received by the transmitter attached to a wheel farthest from the trigger machine among the plurality of wheels,
In the receiver, in the second control unit, the transmitter to which the transmission frame has not been sent is attached to a wheel farthest from the trigger device among the plurality of wheels. The wheel position detection device according to claim 15, wherein the wheel position detection device discriminates. In the transmitter, ID information is stored in the transmission frame transmitted by the first control unit,
In the receiver, when the second control unit determines which of the plurality of wheels the transmitter is attached to, the transmitter is attached to any of the plurality of wheels. The wheel position detection device according to any one of claims 14 to 16, wherein a result of whether or not the vehicle is stored and the ID information stored in the transmission frame are stored in association with each other. The plurality of wheels are two front wheels (6a, 6b) and two rear wheels (6c, 6d),
The trigger machine is arranged on the two rear wheels side with respect to the two front wheels and at a different distance from the right rear wheel (6c) and the left rear wheel (6d) constituting the two rear wheels. The first trigger device (5a) is disposed on the two front wheels side of the two rear wheels, and at a different distance from the right front wheel (6a) and the left front wheel (6b) constituting the two front wheels. A second trigger machine (5b),
In the receiver, when the trigger signal is output from the first trigger machine, at least the transmission frame sent from the transmitter attached to the two rear wheels is received and the second trigger is received. 18. The transmission frame transmitted from the transmitter attached to at least the two front wheels when receiving the trigger signal from a machine, is received at least one of claims 14 to 17. The wheel position detection device described. The plurality of wheels are the right two wheels (6a, 6c) and the left two wheels (6b, 6d),
The trigger device is disposed on the left two wheels side of the right two wheels and is arranged at a different distance from the left front wheel (6b) and the left rear wheel (6d) constituting the left two wheels. A second vehicle (5a) and a second wheel disposed at a different distance from the right front wheel (6a) and the right rear wheel (6c), which are disposed on the right two wheels side of the left two wheels and constituting the right two wheels. A trigger machine (5b),
In the receiver, when the trigger signal is output from the first trigger machine, at least the transmission frame sent from the transmitter attached to the left two wheels is received, and the second trigger machine 18. The transmission frame sent from the transmitter attached to the right two wheels is received at least when the trigger signal is outputted from the receiver. Wheel position detector. A tire pressure detecting device including the wheel position detecting device according to any one of claims 1 to 19,
The transmitter includes a sensing unit (21) that outputs a detection signal related to the tire air pressure 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.

Images