WO2016121366A1 - Wheel position detection device and tire pressure detection system provided with same - Google Patents

Wheel position detection device and tire pressure detection system provided with same Download PDF

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Publication number
WO2016121366A1
WO2016121366A1 PCT/JP2016/000351 JP2016000351W WO2016121366A1 WO 2016121366 A1 WO2016121366 A1 WO 2016121366A1 JP 2016000351 W JP2016000351 W JP 2016000351W WO 2016121366 A1 WO2016121366 A1 WO 2016121366A1
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WIPO (PCT)
Prior art keywords
frame
wheel
transmitter
vehicle
wheels
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PCT/JP2016/000351
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French (fr)
Japanese (ja)
Inventor
昌紘 福田
則昭 岡田
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株式会社デンソー
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Publication of WO2016121366A1 publication Critical patent/WO2016121366A1/en

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60CVEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C23/00Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
    • B60C23/02Signalling devices actuated by tyre pressure
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60CVEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C23/00Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
    • B60C23/02Signalling devices actuated by tyre pressure
    • B60C23/04Signalling devices actuated by tyre pressure mounted on the wheel or tyre
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L17/00Devices or apparatus for measuring tyre pressure or the pressure in other inflated bodies

Definitions

  • the technology of the present disclosure relates to a wheel position detection device that automatically detects at which position of the vehicle a target wheel is mounted, and is suitable for application to a direct tire pressure detection system.
  • TPMS Tire Pressure Monitoring System
  • a transmitter equipped with a sensor such as a pressure sensor is directly attached to a wheel side to which a tire is attached.
  • an antenna and a receiver are provided on the vehicle body side.
  • a registration method there is a method of registration using a tool capable of communicating with a TPMS electronic control device (hereinafter referred to as TPMS-ECU) mounted on a vehicle at an automobile maintenance shop (for example, a dealer). As shown in FIG. 1, there is also an automatic method.
  • TPMS-ECU TPMS electronic control device
  • the wheel speed sensor detects the passage of the tooth of the gear rotated in conjunction with the wheel, and the wheel position is determined based on the variation width of the tooth position at the reception timing of the frame.
  • automatic registration is performed based on a user's registration instruction operation, and the TPMS-ECU detects wheel positions based on vehicle travel.
  • ID information as a candidate for registration (hereinafter referred to as candidate ID) is stored in the memory of the TPMS-ECU. Then, the transmitter of the own vehicle is finally registered from among the candidate IDs.
  • a predetermined condition is set so that irrelevant ID information is excluded from the candidate IDs. .
  • the vehicle when the wheel position is detected based on the acceleration detection signal detected by the acceleration sensor, the vehicle always travels, and therefore the condition of the candidate ID is that the vehicle is traveling. Can do.
  • the vehicle speed is a predetermined speed (for example, 10 km / h) or more, and acceleration on data (the acceleration sensor data indicating that the acceleration sensor is turned on in the frame transmitted from the transmitter) (Hereinafter referred to as G-ON data).
  • G-ON data the acceleration sensor data indicating that the acceleration sensor is turned on in the frame transmitted from the transmitter
  • the acceleration sensor when the wheel speed reaches a predetermined speed, the acceleration component in the centrifugal direction becomes sufficiently larger than the other components so that accurate acceleration detection can be performed.
  • the fact that the acceleration sensor can accurately detect the acceleration is referred to as the acceleration sensor being in an on state.
  • the transmitter is provided with a function of detecting that the acceleration sensor is turned on, and G-ON data is stored in the frame based on the detection result.
  • acceleration off data (hereinafter referred to as G-OFF data) is stored in the frame.
  • G-OFF data acceleration off data
  • the G-ON data As described above, if the G-ON data is included, it is possible to prevent the candidate ID from accepting the ID information of the transmitter of the other vehicle when the vehicle is not traveling. If the G-ON data indicating that the vehicle is traveling is not included in the frame sent from the transmitter, the ID information stored in the frame can be excluded from the candidate ID. As a result, the amount of data stored in the memory of the TPMS-ECU can be reduced. In particular, if the number of other vehicles in the same format as the own vehicle increases in the market, the number of candidate IDs of the transmitter becomes enormous and the wheel ID information of the own vehicle may not be registered. Logic that makes ID information of other vehicles excluded from candidate IDs is useful.
  • the predetermined vehicle speed that the TPMS-ECU includes in the candidate ID is set to a lower value (eg, 10 km / h) than the vehicle speed at which the acceleration sensor is turned on, or a higher value (eg, 40 km / h).
  • a lower value eg, 10 km / h
  • a higher value eg, 40 km / h
  • the speed range in which the acceleration sensor is not turned on yet (range of 10 km / h to the predetermined vehicle speed) ) If a frame storing G-ON data from another vehicle is received while the host vehicle is traveling within this speed range, the ID information stored in the frame is a candidate for each transmitter of the wheels of the host vehicle. Registered as an ID. If the host vehicle continues to travel within this speed range, only those of other vehicles are registered as candidate IDs, and the memory capacity of the TPMS-ECU is filled. May not be registered as.
  • the predetermined vehicle speed is set to a high value
  • the own vehicle is always traveling in a state where the predetermined vehicle speed is not exceeded, the same thing as described above occurs, and the ID information of each transmitter of the wheel of the own vehicle is obtained. There is also a concern that it will not be registered as a candidate ID.
  • One of the objects of the present disclosure is that, in view of the above points, the ID information of the transmitter of the wheel of the own vehicle is accurately determined while suppressing the ID information of the transmitter of the wheel of the other vehicle as a candidate ID.
  • a wheel position detection device is a wheel position detection device applied to a vehicle in which a plurality of wheels including tires are attached to a vehicle body, and is provided on each of the plurality of wheels.
  • a transmitter including a first control unit that generates and transmits a frame including the identification information of the frame, and a frame that is provided on the vehicle body side and receives the frame transmitted from the transmitter via a reception antenna.
  • a receiver having a second control unit that performs wheel position detection that stores the plurality of wheels and the identification information of the transmitter provided in each of the plurality of wheels in association with each other.
  • the transmitter includes an acceleration sensor that outputs a detection signal corresponding to an acceleration including a gravitational acceleration component that changes with rotation of a wheel to which the transmitter is attached, and as a function of the first control unit, Detecting that the wheel speed of the wheel to which the transmitter is attached has reached a predetermined speed at which the acceleration sensor can detect the acceleration, and indicating the state of the acceleration sensor based on the detection result It has a function of storing in the frame.
  • the first control unit has a gravitational acceleration included in the detection signal of the acceleration sensor with the central axis of the wheel to which the transmitter is attached as the center and an arbitrary position in the circumferential direction of the wheel as an angle of 0 °.
  • the angle of the transmitter is detected based on the component, and the frame is repeatedly transmitted at a timing at which the angle becomes a predetermined transmission angle.
  • the second control unit is a gear having an outer peripheral surface having different magnetic resistances, which is rotated in conjunction with the plurality of wheels, and a portion of a tooth which is a conductor and a portion located between the teeth are alternately repeated.
  • gear information indicating the tooth position of the gear is acquired, and the frame is transmitted based on the tooth position at the reception timing of the frame.
  • the wheel position is detected by identifying and registering the wheel to which the transmitter is attached.
  • the second control unit of the receiver is in a state where the vehicle is traveling at a first speed or higher set to be equal to or higher than the predetermined speed, and the state of the acceleration sensor stored in the received frame
  • a first determination unit that determines whether or not the first condition that the acceleration sensor is on is satisfied, and the first determination unit determines that the first condition is satisfied.
  • the candidate registration unit that registers the identification information stored in the received frame as the candidate identification information and the frame that includes the candidate identification information registered by the candidate registration unit are received
  • the vehicle The data indicating the state of the acceleration sensor stored in the received frame is the state in which the acceleration sensor is on, and the vehicle is traveling at the second speed or higher set below the predetermined speed.
  • a second determination unit that determines whether or not the second condition is satisfied, and the reception timing of the received frame when the second determination unit determines that the second condition is satisfied
  • a data updating unit for updating the tooth position data as new data used for the wheel position detection.
  • a criterion for determining that the vehicle state used as the registration condition is running is that a vehicle speed equal to or higher than the first speed at which the acceleration sensor is on is generated.
  • the criterion for determining that the vehicle state used as the data update condition is running is that a vehicle speed equal to or higher than the second speed that is lower than the first speed is generated.
  • a tire air pressure detection system is a tire air pressure detection system including the wheel position detection device described above, wherein the transmitter detects according to the air pressure of the tire provided in each of the plurality of wheels.
  • a sensing unit for outputting a signal, and storing information on tire pressure obtained by signal processing of the detection signal of the sensing unit by the first control unit in a frame, and then transmitting the frame to the receiver.
  • the second control unit detects the air pressure of the tire provided in each of the plurality of wheels from the information related to the tire air pressure.
  • FIG. 1 is a diagram illustrating an overall configuration of a tire air pressure detection device to which the wheel position detection device according to the first embodiment is applied.
  • FIG. 2A is a diagram illustrating a block configuration of the transmitter.
  • FIG. 2B is a diagram showing a block configuration of the TPMS-ECU.
  • FIG. 3 is a timing chart for explaining wheel position detection.
  • FIG. 4 is an image diagram showing changes in gear information.
  • FIG. 5A is a schematic diagram illustrating wheel position determination logic.
  • FIG. 5B is a schematic diagram illustrating the wheel position determination logic.
  • FIG. 5C is a schematic diagram illustrating the wheel position determination logic.
  • FIG. 6A is a chart showing the evaluation result of the wheel position of ID1.
  • FIG. 6B is a chart showing the evaluation result of the wheel position of ID2.
  • FIG. 6C is a chart showing the evaluation result of the wheel position of ID3.
  • FIG. 6D is a chart showing the evaluation result of the wheel position of ID4.
  • FIG. 7 is a flowchart of candidate ID registration processing.
  • FIG. 8 is a flowchart of the data update process.
  • FIG. 1 is a diagram illustrating an overall configuration of a TPMS to which the wheel position detection device according to the first embodiment 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.
  • TPMS in this embodiment is demonstrated.
  • the TPMS is provided in the vehicle 1, and includes a transmitter 2, an ECU for TPMS (hereinafter referred to as TPMS-ECU) 3 serving as a receiver, and a meter 4. Yes.
  • the wheel position detection device uses a transmitter 2 and a TPMS-ECU 3 provided in the TPMS, and wheels provided corresponding to each wheel 5 (5a to 5d) from a brake control ECU (hereinafter referred to as a brake ECU) 10.
  • the wheel position is specified by acquiring gear information obtained from detection signals of the speed sensors 11a to 11d.
  • the transmitter 2 is attached to each of the wheels 5a to 5d, detects the air pressure of the tire attached to the wheels 5a to 5d, and provides information about the tire air pressure indicating the detection result. It is stored in a frame together with the unique ID information of the transmitter 2 and transmitted. In the frame, G-ON data indicating that an acceleration sensor 22 (described later) is turned on or G-OFF data indicating that the acceleration sensor 22 is not turned on is stored. These G-ON data and G-OFF data correspond to data indicating the state of the acceleration sensor 22. Although the acceleration sensor 22 always detects acceleration, when the wheel speed reaches a predetermined speed, the acceleration component in the centrifugal direction becomes sufficiently larger than the other components so that accurate acceleration detection can be performed.
  • the fact that the acceleration sensor 22 can perform accurate acceleration detection in this way is referred to as the acceleration sensor 22 being in an on state.
  • the transmitter 2 has a function of detecting that the acceleration sensor 22 is turned on, and stores G-ON data or G-OFF data in a frame based on the detection result. Yes.
  • the transmitter 2 is provided with a physical switch (not shown) in which a movable contact that is displaced according to acceleration in the centrifugal direction is in contact with a fixed contact. Is detected to have been turned on.
  • the TPMS-ECU 3 is attached to the vehicle body 6 side of the vehicle 1 and receives the frame transmitted from the transmitter 2 and performs various processes and calculations based on the detection signal stored therein. Thus, wheel position detection and tire air pressure detection are performed.
  • the transmitter 2 creates a frame by, for example, FSK (frequency shift keying), and the TPMS-ECU 3 demodulates the frame to read data in the frame to detect the wheel position and the tire air pressure.
  • 2A and 2B show block configurations of the transmitter 2 and the TPMS-ECU 3.
  • the transmitter 2 includes a sensing unit 21, an acceleration sensor 22, a microcomputer 23, a transmission circuit 24, and a transmission antenna 25, and is based on power supply from a battery (not shown). Each part is driven.
  • the sensing unit 21 includes a diaphragm type pressure sensor 21a and a temperature sensor 21b, for example, and outputs a detection signal corresponding to the tire pressure and a detection signal corresponding to the temperature.
  • the acceleration sensor 22 is used to detect the position of the sensor itself at the wheels 5a to 5d to which the transmitter 2 is attached, that is, to detect the position of the transmitter 2 and the vehicle speed.
  • the acceleration sensor 22 according to the present embodiment detects, for example, acceleration corresponding to accelerations in both directions perpendicular to the radial direction of each wheel 5a to 5d, that is, the circumferential direction, among the accelerations acting on the wheels 5a to 5d when the wheels 5a to 5d rotate. Output a signal.
  • the microcomputer 23 is a well-known one having a control unit (first control unit) and the like, and executes predetermined processing according to a program stored in a memory in the control unit.
  • Individual ID information including identification information unique to the transmitter for identifying each transmitter 2 and identification information unique to the vehicle for identifying the host vehicle is stored in the memory in the control unit.
  • the microcomputer 23 receives the detection signal related to the tire pressure from the sensing unit 21, processes the signal and processes it as necessary, and stores the information related to the tire pressure in the frame together with the ID information of each transmitter 2. . Further, the microcomputer 23 monitors the detection signal of the acceleration sensor 22 to detect the position (angle detection) of the transmitter 2 on the wheels 5a to 5d to which the transmitters 2 are attached, or to detect the vehicle speed. Yes. When the microcomputer 23 creates the frame, the microcomputer 23 transmits the frame (data transmission) from the transmission antenna 25 to the TPMS-ECU 3 via the transmission circuit 24 based on the position detection result of the transmitter 2 and the vehicle speed detection result. )I do.
  • the microcomputer 23 starts frame transmission on the condition that the vehicle 1 is traveling, and at a timing at which the angle of the acceleration sensor 22 becomes a predetermined angle based on the detection signal of the acceleration sensor 22. Repeated frame transmission. Whether the vehicle is running is determined based on the vehicle speed detection result, and the angle of the acceleration sensor 22 is determined based on the position detection result of the transmitter 2 based on the detection signal of the acceleration sensor 22. .
  • the microcomputer 23 detects the vehicle speed using the detection signal of the acceleration sensor 22, and determines that the vehicle 1 is running when the vehicle speed becomes a predetermined speed (for example, 5 km / h) or more.
  • the output of the acceleration sensor 22 includes acceleration based on centrifugal force (centrifugal acceleration).
  • the vehicle speed can be calculated by integrating the centrifugal acceleration and multiplying the coefficient. For this reason, the microcomputer 23 calculates the centrifugal acceleration by removing the gravitational acceleration component from the output of the acceleration sensor 22, and calculates the vehicle speed based on the centrifugal acceleration.
  • the acceleration sensor 22 Since the acceleration sensor 22 outputs detection signals corresponding to the rotations of the wheels 5a to 5d, the gravitational acceleration component is included in the detection signals during traveling, and the amplitude corresponding to the wheel rotation is increased. Signal.
  • the amplitude of the detection signal is the negative maximum amplitude when the transmitter 2 is located at the upper position around the central axis of the wheels 5a to 5d, zero when located at the horizontal position, and located at the lower position. The maximum positive amplitude is obtained. Therefore, the position of the acceleration sensor 22 can be detected based on this amplitude, and when the acceleration sensor 22 is located at an upper position around the angle of the position of the transmitter 2, for example, the central axis of each wheel 5a to 5d. It is possible to grasp the angle formed by the acceleration sensor 22 when the angle is set to 0 °.
  • the frame transmission from each transmitter 2 is performed at the start timing when the acceleration sensor 22 reaches a predetermined angle at the same time when the vehicle speed reaches the predetermined speed or after the vehicle speed reaches the predetermined speed.
  • the frame is transmitted repeatedly at the timing when the angle formed by the acceleration sensor 22 becomes the same angle as the first frame transmission.
  • the angle formed by the acceleration sensor 22 may be the same as that at the time of the first frame transmission.
  • the frame transmission is always performed every time the angle is reached. For example, it is preferable that frame transmission is performed only once in a predetermined time (for example, 15 seconds).
  • the transmission circuit 24 functions as an output unit that transmits a frame transmitted from the microcomputer 23 to the TPMS-ECU 3 through the transmission antenna 25.
  • frame transmission for example, radio waves in the RF band are used.
  • the transmitter 2 configured in this way is attached to an air injection valve in each of the wheels 5a to 5d, for example, and is arranged so that the sensing unit 21 is exposed inside the tire.
  • the transmitter 2 detects the tire air pressure of the wheel to which the transmitter 2 is attached, and when the vehicle speed exceeds a predetermined speed as described above, the angle of the acceleration sensor 22 of each wheel 5a to 5d becomes a predetermined angle.
  • Frame transmission is performed repeatedly through the transmission antenna 25 provided in each transmitter 2 at the timing. After that, it is possible to perform frame transmission from the transmitter 2 at the timing at which the angle of the acceleration sensor 22 of each wheel 5a to 5d becomes a predetermined angle, but it is better to increase the transmission interval in consideration of the battery life.
  • the mode is switched from the wheel position determination mode to the periodic transmission mode, and frame transmission is performed at a longer fixed period (for example, every minute), so that the TPMS-ECU3 side A signal related to the tire pressure is periodically transmitted to.
  • the transmission timing of each transmitter 2 can be shifted, and reception by the TPMS-ECU 3 side due to radio wave interference from a plurality of transmitters 2 is possible. It can be prevented from disappearing.
  • the TPMS-ECU 3 includes a receiving antenna 31, a receiving circuit 32, a microcomputer 33, and the like.
  • the TPMS-ECU 3 acquires the gear information from the brake ECU 10 through an in-vehicle LAN such as CAN as will be described later, and the teeth indicated by the number of teeth (or the number of teeth) of the gears rotated together with the wheels 5a to 5d. Get the position.
  • the receiving antenna 31 is for receiving a frame sent from each transmitter 2.
  • the receiving antenna 31 is fixed to the vehicle body 6 and may be an internal antenna disposed in the main body of the TPMS-ECU 3, or may be an external antenna in which wiring is extended from the main body.
  • the receiving circuit 32 functions as an input unit that receives a transmission frame from each transmitter 2 received by the receiving antenna 31 and sends the frame to the microcomputer 33.
  • the receiving circuit 32 transmits the received signal to the microcomputer 33.
  • the microcomputer 33 corresponds to the second control unit, and executes wheel position detection according to a program stored in a memory in the microcomputer 33. Specifically, the microcomputer 33 performs wheel position detection based on the relationship between the information acquired from the brake ECU 10 and the reception timing at which the transmission frame from each transmitter 2 is received. From the brake ECU 10, in addition to the wheel speed information of the wheels 5a to 5d, gear information of the wheel speed sensors 11a to 11d provided corresponding to the wheels 5a to 5d is acquired every predetermined period (for example, 10 ms). Yes.
  • Gear information is information indicating the tooth positions of gears (gears) that are rotated together with the wheels 5a to 5d.
  • the wheel speed sensors 11a to 11d are constituted by, for example, electromagnetic pickup sensors arranged to face the gear teeth, and change the detection signal as the gear teeth pass. Since these types of wheel speed sensors 11a to 11d output square pulse waves corresponding to the passage of teeth as detection signals, the rising and falling of the square pulse waves pass through the tooth edge of the gear. Will be expressed. Therefore, the brake ECU 10 counts the number of teeth of the gear, that is, the number of passing edges, from the number of rising and falling edges of the detection signals of the wheel speed sensors 11a to 11d, and the tooth edge at that time is counted every predetermined period. The number is transmitted to the microcomputer 33 as gear information indicating the tooth position. Thereby, in the microcomputer 33, it is possible to grasp which tooth of the gear has passed.
  • the number of tooth edges is reset every time the gear rotates once. For example, when the number of teeth provided on the gear is 48 teeth, the number of edges is counted as a total of 96 from 0 to 95, and when the count value reaches 95, it is returned to 0 and counted again.
  • the number of tooth edges of the gear is transmitted from the brake ECU 10 to the microcomputer 33 as gear information.
  • the number of teeth may be a count value of the number of passing teeth.
  • the number of edges or teeth passed during the predetermined period is transmitted to the microcomputer 33, and the microcomputer 33 adds the number of edges or teeth passed during the predetermined period to the previous number of edges or teeth. You may make it count the number of edges or the number of teeth in the period. That is, it is only necessary that the microcomputer 33 can finally acquire the number of edges or the number of teeth in the cycle as gear information.
  • the brake ECU 10 resets the number of gear teeth (or the number of teeth) every time the power is turned off, but again starts measuring at the same time when the power is turned on or when the vehicle speed reaches the predetermined vehicle speed. ing. Thus, even if the power is turned off every time the power is turned off, the same teeth are represented by the same number of edges (or the number of teeth) while the power is turned on.
  • the microcomputer 33 measures the reception timing when the frame transmitted from each transmitter 2 is received, and the frame reception timing is determined from the number of edges (or the number of teeth) of the acquired gear.
  • the wheel position is detected based on the number of edges (or the number of teeth) of the gear. As a result, it is possible to perform wheel position detection that specifies to which wheel 5a to 5d each transmitter 2 is attached. A specific method for detecting the wheel position will be described in detail later.
  • the microcomputer 33 stores the ID information of each transmitter 2 in association with the position of each wheel 5a to 5d to which each transmitter 2 is attached based on the result of wheel position detection. After that, based on the ID information and tire pressure data stored in the transmission frame from each transmitter 2, the tire pressure of each wheel 5a to 5d is detected, and an electrical signal corresponding to the tire pressure is sent to CAN or the like. Is output to the meter 4 through the in-vehicle LAN. For example, the microcomputer 33 detects a decrease in tire air pressure by comparing the tire air pressure with a predetermined threshold Th, and outputs a signal to that effect to the meter 4 when a decrease in tire air pressure is detected. As a result, the meter 4 is informed that the tire air pressure of any of the four wheels 5a to 5d has decreased.
  • the meter 4 functions as an alarm unit, and as shown in FIG. 1, is arranged at a place where the driver can visually recognize, and is configured by a meter display or the like installed in an instrument panel in the vehicle 1, for example. .
  • a signal indicating that the tire air pressure has decreased is sent from the microcomputer 33 in the TPMS-ECU 3, the meter 4 displays a decrease in tire air pressure while identifying the wheels 5a to 5d. Informs that the tire pressure of the specific wheel has decreased.
  • the microcomputer 23 monitors the detection signal of the acceleration sensor 22 at every predetermined sampling period based on the power supply from the battery, thereby determining the vehicle speed and the angle of the acceleration sensor 22 at each of the wheels 5a to 5d. Detected. Then, when the vehicle speed reaches a predetermined speed, the microcomputer 23 repeatedly transmits frames at a timing at which the angle of the acceleration sensor 22 becomes a predetermined angle. For example, frame transmission from each transmitter 2 is performed with a predetermined angle when the vehicle speed reaches a predetermined speed or a start timing when the acceleration sensor 22 reaches a predetermined angle after the vehicle speed reaches the predetermined speed. I have to. The frame is transmitted repeatedly at the timing when the angle formed by the acceleration sensor 22 becomes the same angle as the first frame transmission.
  • the gear information of the wheel speed sensors 11a to 11d provided corresponding to the wheels 5a to 5d is acquired from the brake ECU 10 at predetermined intervals (for example, 10 ms). Then, the TPMS-ECU 3 measures the reception timing when the frame transmitted from each transmitter 2 is received, and when the frame reception timing is selected from the number of gear edges (or the number of teeth). Get the number of gear edges (or the number of teeth).
  • the reception timing of the frame transmitted from each transmitter 2 does not always coincide with the cycle of acquiring gear information from the brake ECU 10.
  • the number of edges (or the number of teeth) of the gear indicated by the gear information acquired in the cycle closest to the reception timing of the frame among the cycles in which the gear information is acquired from the brake ECU 10, that is, the cycle immediately before or immediately after that Can be used as the number of gear edges (or the number of teeth).
  • the frame reception timing is obtained by using the number of gear edges (or the number of teeth) indicated by the gear information acquired in the period immediately before and after the frame reception timing from the period in which the gear information is acquired from the brake ECU 10.
  • the number of edges (or the number of teeth) of the gear may be calculated.
  • the intermediate value of the number of gear edges (or the number of teeth) indicated by the gear information acquired immediately before and after the frame reception timing is used as the number of gear edges (or the number of teeth) at the frame reception timing. Can be used.
  • the operation of obtaining the number of gear edges (or the number of teeth) at the reception timing of the frame is repeated every time the frame is received, and the number of gear edges (or the number of gear edges at the received frame reception timing)
  • the wheel position is detected based on the number of teeth. Specifically, the variation in the number of gear edges (or the number of teeth) at the frame reception timing is within a predetermined range set based on the number of gear edges (or the number of teeth) at the previous reception timing.
  • the wheel position is detected by determining whether or not there is.
  • the tooth position indicated by the number of gear edges (or the number of teeth) at the frame reception timing Is almost the same as the previous time. For this reason, the variation in the number of edges (or the number of teeth) of the gears at the frame reception timing is small and falls within a predetermined range. This is true even when multiple frames are received, and the variation in the number of gear edges (or the number of teeth) at the reception timing of each frame is within a predetermined range determined at the first frame reception timing. It will fit.
  • the tooth position indicated by the number of edges (or the number of teeth) of the gear at the reception timing of the frame transmitted from the transmitter 2 of the other wheel varies.
  • the number of edges (or the number of teeth) of the gear at the reception timing of the frame for the wheel that has received the frame are nearly identical.
  • the rotation state of the wheels 5a to 5d varies depending on road conditions, turning or lane change, and the rotation states of the wheels 5a to 5d cannot be completely the same. For this reason, for a wheel that is different from the wheel that received the frame, the tooth position indicated by the number of gear edges (or the number of teeth) at the frame reception timing varies.
  • the tooth position indicated by the number of gear edges (or the number of teeth) at the frame reception timing varies.
  • the wheel position is detected by determining whether or not the variation is within a predetermined range.
  • the variation allowable width which is the allowable width for the number of gear edges (or the number of teeth), is a value corresponding to a range of 180 ° centered on the first reception angle (the range of the first reception angle ⁇ 90 °).
  • the number of edges is a range of ⁇ 24 edges centered on the number of edges at the first reception
  • the number of teeth is a range of ⁇ 12 teeth centered on the number of teeth at the first reception. In this case, as shown in FIG.
  • the number of gear edges (or the number of teeth) at the time of the second frame reception is within the range of allowable variation determined by the first frame reception, the number of edges.
  • the wheel (or the number of teeth) may coincide with the wheel on which the frame was transmitted, and is TRUE (correct).
  • the variation allowable width is determined around the second reception angle that is the angle of the transmitter 2 at the time of the second frame reception, and is equivalent to 180 ° ( ⁇ 90 °) around the second reception angle. Value. For this reason, a variation allowable width of 180 ° ( ⁇ 90 °) centered on the first reception angle that is the previous allowable variation width and a variation allowable width of 180 ° ( ⁇ 90 °) centered on the second reception angle
  • the overlapping portion becomes a new variation allowable width (edge number range is 12 to 48), and the new variation allowable width can be narrowed to the overlapping range.
  • the number of gear edges (or the number of teeth) is acquired at each reception timing of the frame, and the corresponding wheel (left front wheel) is obtained.
  • a transmitter that transmits the frame out of the range is transmitted. 2 is excluded from the attached wheel candidates. And the wheel which was not excluded until the last is registered as a wheel with which the transmitter 2 with which the flame
  • the right front wheel FR, the right rear wheel RR, and the left rear wheel RL are excluded from the candidates in this order, and the remaining left front wheel FL is finally attached to the transmitter 2 to which the frame is transmitted.
  • the wheel is registered in association with the ID information.
  • the microcomputer 33 stores the ID information of each transmitter 2 that has transmitted the frame in association with the position of the wheel to which it is attached.
  • the TPMS-ECU 3 receives the frame transmitted when the vehicle speed reaches the predetermined speed, and stores the gear information at the reception timing. However, the TPMS-ECU 3 stores a predetermined traveling stop determination speed (for example, 5 km). / H) When it becomes below, the gear information so far is discarded. When the vehicle starts running again, the wheel position is newly detected as described above.
  • the basic wheel position detection is performed by the above method. As a result, it is possible to detect the wheel positions of the left front wheel FL, the right front wheel FR, the left rear wheel RL, and the right rear wheel RR, which are traveling wheels.
  • the ID information stored in the frame can be a candidate ID.
  • the timing at which the frame transmitted from the transmitter of the other vehicle is received does not match the tooth position of the gear of any wheel of the own vehicle. For this reason, it can avoid registering the ID information of the transmitter of another vehicle, and can register only the ID information of the transmitter 2 of the own vehicle.
  • the registration method shown in Patent Document 1 it is possible to prevent registration of ID information of a transmitter of another vehicle. That is, in the above wheel position detection, when a frame including ID information from a transmitter attached to a wheel of another vehicle is received during wheel position detection when no existing ID information of the host vehicle is registered.
  • the ID information of the transmitter can also be a candidate ID.
  • the transmitter 2 attached to the wheels 5a to 5d of the host vehicle is replaced, and the number of ID information of frames that can be received is In some cases, the number is less than the number of registered ID information. In such a case, when a frame including ID information from a transmitter attached to a wheel of another vehicle is received during wheel position detection, the ID information of the transmitter can also be a candidate ID.
  • the ID information is only included when the tooth position at the frame reception timing is included in the variation allowable range continuously for a predetermined number of times (for example, 10 times). Is registered.
  • the number of gear edges (or teeth) acquired at each frame reception timing is also received for that frame, as in the case of the host vehicle. It is determined whether or not (number) is within the range of variation tolerance. And, similarly to the transmitter 2 of the own vehicle, for the frame transmitted from the transmitter of the other vehicle, the wheel that is out of the range of the allowable variation range is selected from the wheel candidates attached to the transmitter 2 to which the frame is transmitted. Will be excluded. At this time, since the elimination method is used, at the time when only one wheel is finally left without being excluded in each frame, the wheel candidate to which the transmitter 2 to which the wheel transmits the frame is attached. It becomes.
  • the ID information of the transmitter attached to the wheels of the other vehicle is erroneously registered as that of the own vehicle.
  • the frame transmitted from the transmitter attached to the wheel of the other vehicle is not from the own vehicle, the frame is likely to vary, and the frame transmitted from the transmitter 2 attached to the wheels 5a to 5d of the own vehicle. It is apt to be excluded from the wheel candidates earlier. For this reason, most of the frames transmitted from the transmitters of the wheels of other vehicles are identified as wheel candidates that are attached to the transmitters that transmitted the frames. It is easy to become the state that was done.
  • the ID information registration condition is that the tooth position at the reception timing of the frame is continuously included within the tolerance range after the wheel is specified, the other vehicle is in the meantime.
  • the tooth position of the reception timing of the frame from the transmitter is out of the tolerance range. Therefore, it is possible to prevent the ID information of the transmitter attached to the wheels of the other vehicle from being erroneously registered as that of the own vehicle.
  • the TPMS-ECU 3 executes the candidate ID registration process shown below, thereby increasing the number of candidate IDs. Is suppressed.
  • the processing shown in FIG. 7 is performed for selecting candidate IDs to be subjected to wheel position detection when the above-described processing for detecting the wheel position of the traveling wheel is started. Then, only the candidate ID selected here is subjected to the data update process shown in FIG. 8 and is subjected to wheel position detection by the wheel position determination logic described above.
  • the TPMS-ECU 3 enters the ID registration mode.
  • the TPMS-ECU 3 executes the processes shown in FIGS. 7 and 8 together with the above-described wheel position detection process at every predetermined control cycle.
  • step 100 when an RF reception, that is, a frame transmitted as an RF band radio wave is received, the processing from step 110 is executed.
  • step 110 it is determined whether or not the vehicle state is traveling and G-ON data is stored in the received frame. That is, it is determined here whether or not the host vehicle is traveling and the acceleration sensor 22 provided in the transmitter 2 is in an on state.
  • Whether the vehicle state is traveling or not is determined by obtaining vehicle speed data from the brake ECU 10 because the vehicle ECU calculates the vehicle speed based on detection signals from the wheel speed sensors 11a to 11d, for example. Can do.
  • the vehicle speed is generated, the vehicle state is assumed to be running, but in this step, the vehicle speed becomes equal to or higher than the predetermined vehicle speed on the basis of the predetermined vehicle speed at which the acceleration sensor 22 is turned on.
  • the vehicle state is assumed to be traveling when the vehicle speed equal to or higher than the first speed is generated.
  • the vehicle speed at which the acceleration sensor 22 is turned on varies depending on variations in the acceleration sensor 22, but for example, if it is 40 km / h or more, the acceleration sensor 22 is surely turned on, so the vehicle speed here is 40 km / h. It is assumed that the vehicle state is running when h or more.
  • the candidate ID registration condition is set such that the vehicle state is traveling and that the G-ON data is stored in the received frame.
  • the ID information of each transmitter of the wheel of the host vehicle is registered as the candidate ID, such that only the other vehicle is registered as the candidate ID and the memory capacity of the TPMS-ECU 3 is full. There is a possibility of disappearing.
  • the vehicle speed is higher than or equal to the first speed as a determination condition that the vehicle state, which is one of the candidate ID registration conditions in the determination of step 110, is running. I am going to do that.
  • the vehicle speed is higher than or equal to the first speed as a determination condition that the vehicle state, which is one of the candidate ID registration conditions in the determination of step 110, is running. I am going to do that.
  • step 110 If an affirmative determination is made in step 110, the process proceeds to step 120, where the ID information stored in the received frame is registered (stored) in the memory of the TPMS-ECU 3 as a candidate ID, and the process proceeds to the data update process shown in FIG. . That is, by narrowing down the candidate ID registration conditions and narrowing down the number of candidate IDs to be registered, the data update process shown in FIG. Make it easier to update data.
  • step 200 when a frame transmitted as an RF reception, that is, an RF band radio wave is received, the processes in and after step 210 are performed. Execute.
  • step 210 whether the vehicle state is running and the received frame is of a candidate ID storing G-ON data, that is, whether it is ID information already registered in the candidate ID registration process shown in FIG. Determine whether or not. At this time, on condition that it is a candidate ID, the ID information registered as the candidate ID is not allowed to proceed to the processing after step 220.
  • the determination criterion that the vehicle state is running is loosened from step 110. Specifically, in this step, when a vehicle speed that is lower than the predetermined vehicle speed and that can accurately calculate the vehicle speed is generated with reference to the predetermined vehicle speed at which the acceleration sensor 22 is turned on. The vehicle state is running. The vehicle speed at which the acceleration sensor 22 is not turned on varies depending on variations in the acceleration sensor 22, but for example, if it is 5 km / h, the acceleration sensor 22 is not turned on.
  • the vehicle speed that can be calculated with high accuracy varies depending on the accuracy of the wheel speed sensors 11a to 11d, but can be calculated with high accuracy if the vehicle speed is 5 km / h or more, for example. Therefore, here, it is determined that the vehicle state is traveling when the vehicle speed is 5 km / h or more.
  • the G-ON data is continuously recorded in the frame until it is confirmed that the acceleration sensor 22 is turned on once or until a predetermined time elapses after the vehicle stops. included. That is, the G-ON data is not stored in the frame until the vehicle speed reaches a predetermined speed and the acceleration sensor 22 is turned on. Once the acceleration sensor 22 is turned on, the G-ON data is not detected even if the vehicle speed decreases. Data remains stored in the frame. Therefore, even if the vehicle speed is near the second speed, which is lower than the first speed, as in step 210, the G-ON data can be confirmed.
  • step 220 data update is performed for one of the ID information stored in the received frame, that is, one of the candidate IDs.
  • the candidate ID gear information at the reception timing of the frame is acquired, and it is determined whether or not the number of gear edges (or the number of teeth) indicated by the gear ID is included in the variation allowable width.
  • Data update for wheel position detection according to the wheel position specifying logic is performed. Based on this, as shown in FIGS. 6A to 6D, each time a frame is received, the candidate ID is updated, and the wheel position is detected.
  • the tire air pressure is detected. Specifically, when detecting tire air pressure, frames are transmitted from each transmitter 2 at regular intervals, and every time a frame is transmitted from each transmitter 2, frames for four traveling wheels are converted into TPMS- Received by the ECU 3. Then, the TPMS-ECU 3 identifies which frame is sent from the transmitter 2 attached to the wheels 5a to 5d based on the ID information stored in each frame, and determines each frame from information related to tire pressure. The tire pressure of the wheels 5a to 5d is detected. As a result, a decrease in tire air pressure of each of the wheels 5a to 5d can be detected, and it is possible to identify which tire air pressure of the wheels 5a to 5d is decreasing.
  • the fact is notified to the meter 4 so that the meter 4 displays a display indicating the decrease in tire air pressure while identifying the wheels 5a to 5d, and the tire air pressure of the specific wheel is indicated to the driver. Announcing a drop in
  • the tooth positions of the gears 12a to 12d are shown based on the detection signals of the wheel speed sensors 11a to 11d that detect the passage of the teeth of the gears 12a to 12d rotated in conjunction with the wheels 5a to 5d.
  • Gear information is acquired every predetermined period.
  • the variation allowable width is set based on the tooth position at the reception timing of the frame and the tooth position at the reception timing of the frame after setting the variation allowable width is outside the range of the variation allowable width, The wheel is excluded from the wheel candidates attached to the transmitter 2 to which the frame is transmitted, and the remaining wheels are registered as wheels to which the transmitter 2 to which the frame is transmitted is attached. For this reason, the wheel position of the traveling wheel can be specified without a large amount of data.
  • a criterion for determining that the vehicle state used as the registration condition is running is that a vehicle speed equal to or higher than the first speed at which the acceleration sensor 22 is on is generated.
  • the criterion for determining that the vehicle state used as the data update condition is running is that a vehicle speed equal to or higher than the second speed that is lower than the first speed is generated.
  • the G-ON data is included in the frame.
  • the ID information of the wheel of the other vehicle in which is included is not registered as a candidate ID.
  • the ID information of the wheels of other vehicles whose G-OFF data is included in the frame is not registered as candidate IDs.
  • the data can be updated if the vehicle speed is equal to or higher than the second speed thereafter.
  • the wheel position detection can be completed earlier. In other words, once it is confirmed that the acceleration sensor 22 is turned on, the G-ON data remains included in the frame during the wheel position detection. As long as it is determined that the vehicle is traveling at a low vehicle speed.
  • the variation allowable width is changed at each frame reception timing, and the variation allowable width is gradually narrowed.
  • the method of detecting the wheel position on the traveling wheel side may be another method, for example, a method in which the variation allowable width is constant and is not gradually narrowed.
  • the variation allowable width is changed at each frame reception timing so that the variation allowable width is gradually narrowed.
  • the variation allowable width set around the tooth position is constant. .
  • the variation allowable width set around this tooth position can also be changed.
  • the variation in the tooth position may increase as the vehicle speed increases. For this reason, it is possible to set a more accurate variation allowable width by increasing the variation allowable width as the vehicle speed increases.
  • the longer the sampling period when the acceleration sensor 22 performs acceleration detection the lower the timing detection accuracy when the angle of the acceleration sensor 22 becomes a predetermined angle, and therefore the variation tolerance is changed accordingly.
  • a more accurate variation tolerance can be set. In that case, since the transmitter 2 knows the sampling period and the like, the frame transmitted by the transmitter 2 can be transmitted including data for determining the variation allowable width.
  • the angle at which frame transmission is performed is that the position where the angle is 0 ° is when the acceleration sensor 22 is positioned above the center axis of each wheel 5a to 5d.
  • this is merely an example, and an arbitrary position in the circumferential direction of the wheel may be set to 0 °.
  • the TPMS-ECU 3 acquires the gear information from the brake ECU 10. However, since it is sufficient that the TPMS-ECU 3 can acquire the number of teeth or the number of teeth of the gear as the gear information, it may be acquired from another ECU, or the detection signals of the wheel speed sensors 11a to 11d are input, The number of teeth or the number of teeth of the gear may be acquired from the detection signal.
  • the case where the TPMS-ECU 3 and the brake ECU 10 are configured as separate ECUs has been described, but there may be a case where they are configured as a single ECU in which these are integrated.
  • the ECU directly inputs the detection signals of the wheel speed sensors 11a to 11d, and acquires the number of teeth or the number of teeth of the gear from the detection signals.
  • the number of teeth or the number of teeth of the gear can always be obtained, unlike the case where these pieces of information are obtained every predetermined period, based on the gear information exactly at the reception timing of the frame. Wheel position detection can be performed.
  • the wheel position detection device provided for the vehicle 1 provided with the four wheels 5a to 5d serving as the traveling wheels has been described.
  • a vehicle having a larger number of traveling wheels It can be set as embodiment similarly.
  • the wheel speed sensors 11a to 11d can detect the passage of gear teeth that are rotated in conjunction with the rotation of the wheels 5a to 5d. For this reason, as a gear, what is necessary is just the structure from which the magnetic resistance differs in which the part located in between the tooth
  • the outer edge portion is made uneven so that the outer peripheral surface is not only a general structure composed of a convex portion that becomes a conductor and a space that becomes a nonconductor, but, for example, the outer peripheral surface becomes a conductor and a nonconductor
  • a rotor switch made of an insulator is also included (see, for example, JP-H10-048233A).
  • the wheel position detection is basically performed when the vehicle actually travels, but if the vehicle can rotate each wheel, such as a four-wheel drive vehicle, a device capable of virtual traveling such as a chassis dynamo. Since it can be implemented also when using, traveling is not limited to actual traveling.
  • the steps shown in each figure correspond to units (means) that execute various processes. That is, the part that executes the process of step 110 corresponds to the first determination unit (means), and the part that executes the process of step 120 corresponds to the candidate registration part (means). Further, the part that executes the process of step 210 corresponds to the second determination unit (means), and the part that executes the process of step 220 corresponds to the data update part (means).
  • embodiment is not limited to the above-mentioned embodiment.
  • embodiments obtained by appropriately combining technical parts disclosed in different embodiments are also included in the scope of the embodiments of the present disclosure.

Abstract

Provided is a wheel position detection device. This wheel position detection device is provided with: a transmitter (2) that is provided to each wheel and transmits a frame that includes unique ID information; and a receiver (3) that has a second control unit (33) that carries out wheel position detection whereby candidate ID information for a candidate to be registered is selected from among the ID information transmitted by the transmitter, the information, from among the candidate ID information, that corresponds to the transmitter provided to the wheels is identified, and the wheels and the ID information for the transmitters are stored in association with each other. When registering a candidate ID, the second control unit (33) restrains the number of pieces of registered ID information by making registration conditions strict, and facilitates data update for ID information that has been temporarily registered as candidate ID information.

Description

車輪位置検出装置およびそれを備えたタイヤ空気圧検出システムWheel position detection device and tire air pressure detection system including the same 関連出願の相互参照Cross-reference of related applications
 本出願は、2015年1月28日に出願された日本国特許出願2015-14544号に基づくものであり、その開示をここに参照により援用する。 This application is based on Japanese Patent Application No. 2015-14544 filed on January 28, 2015, the disclosure of which is incorporated herein by reference.
 本開示の技術は、対象車輪が車両のどの位置に搭載されている車輪かを自動的に検出する車輪位置検出装置に関するものであり、ダイレクト式のタイヤ空気圧検出システムに適用して好適である。 The technology of the present disclosure relates to a wheel position detection device that automatically detects at which position of the vehicle a target wheel is mounted, and is suitable for application to a direct tire pressure detection system.
 従来より、タイヤ空気圧検出システム(以下、TPMS:Tire Pressure Monitoring Systemという)の1つとして、ダイレクト式のものがある。このタイプのTPMSでは、タイヤが取り付けられた車輪側に、圧力センサ等のセンサが備えられた送信機が直接取り付けられている。また、車体側には、アンテナおよび受信機が備えられており、センサからの検出信号が送信機から送信されると、アンテナを介して受信機にその検出信号が受信され、タイヤ空気圧の検出が行われる。 Conventionally, there is a direct type as one of tire pressure detection systems (hereinafter referred to as TPMS: Tire Pressure Monitoring System). In this type of TPMS, 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. Done.
 このようなダイレクト式のTPMSでは、送信されてきたデータが自車両のものであるかどうか及び送信機がどの車輪に取り付けられたものかを判別できるようにする必要がある。このため、送信機が送信するデータ中に、自車両か他車両かを判別するため及び送信機が取り付けられた車輪を判別するためのID情報を個々に付与している。 In such a direct TPMS, it is necessary to be able to determine whether the transmitted data belongs to the own vehicle and which wheel the transmitter is attached to. For this reason, ID information for discriminating whether the vehicle is the own vehicle or another vehicle and discriminating the wheel to which the transmitter is attached is individually given in the data transmitted by the transmitter.
 送信データに含まれるID情報から送信機の位置を特定するためには、各送信機のID情報を各車輪の位置と関連づけて受信機側に予め登録しておく必要がある。このため、タイヤのローテーション時や冬用タイヤ交換などの際には、送信機のID情報と車輪の位置関係を受信機に登録し直す必要がある。この場合、登録方法として、自動車整備場(例えばディーラ)等で車両に搭載したTPMSの電子制御装置(以下、TPMS-ECUという)と通信できるツールを用いて登録する方法があるが、例えば特許文献1に示すように、自動的に行う方法もある。 In order to identify the position of the transmitter from the ID information included in the transmission data, it is necessary to register the ID information of each transmitter in advance on the receiver side in association with the position of each wheel. For this reason, it is necessary to re-register the ID information of the transmitter and the positional relationship of the wheels with the receiver at the time of tire rotation or winter tire replacement. In this case, as a registration method, there is a method of registration using a tool capable of communicating with a TPMS electronic control device (hereinafter referred to as TPMS-ECU) mounted on a vehicle at an automobile maintenance shop (for example, a dealer). As shown in FIG. 1, there is also an automatic method.
 具体的には、特許文献1に示す装置では、車輪側の送信機に備えた加速度センサの加速度検知信号に基づいて車輪が所定の回転位置(回転角度)になったことを検出し、車輪側からフレーム送信を行わせている。そして、ユーザの登録指示操作が行われると、車輪と連動して回転させられる歯車の歯の通過を車輪速度センサで検出し、フレームの受信タイミングでの歯位置のバラツキ幅に基づいて、車輪位置を特定している。すなわち、特許文献1に示す装置では、ユーザの登録指示操作に基づいて自動登録を行っており、車両の走行に基づいてTPMS-ECUに車輪位置検出を行わせている。 Specifically, in the apparatus shown in Patent Document 1, it is detected that the wheel has reached a predetermined rotation position (rotation angle) based on the acceleration detection signal of the acceleration sensor provided in the transmitter on the wheel side, and the wheel side Frame transmission. When the user's registration instruction operation is performed, the wheel speed sensor detects the passage of the tooth of the gear rotated in conjunction with the wheel, and the wheel position is determined based on the variation width of the tooth position at the reception timing of the frame. Has been identified. That is, in the apparatus shown in Patent Document 1, automatic registration is performed based on a user's registration instruction operation, and the TPMS-ECU detects wheel positions based on vehicle travel.
JP-2010-122023AJP-2010-122023A
 上記した各車輪の位置と関連付けた各送信機のID情報の自動登録を実施する際には、登録する候補となるID情報(以下、候補IDという)をTPMS-ECUのメモリに記憶していき、その候補IDの中から自車両の送信機を最終的に登録することになる。 When performing automatic registration of the ID information of each transmitter associated with the position of each wheel described above, ID information as a candidate for registration (hereinafter referred to as candidate ID) is stored in the memory of the TPMS-ECU. Then, the transmitter of the own vehicle is finally registered from among the candidate IDs.
 このとき、候補IDが多いと、TPMS-ECUのメモリに記憶させるデータ量がメモリ容量に達してしまうことから、所定の条件を設定し、無関係のID情報が候補IDから除かれるようにしている。具体的には、加速度センサで検出される加速度検知信号に基づいて車輪位置を検出する場合には、必ず車両の走行を伴うことから、車両が走行中であることを候補IDの条件とすることができる。 At this time, if the number of candidate IDs is large, the amount of data stored in the memory of the TPMS-ECU reaches the memory capacity. Therefore, a predetermined condition is set so that irrelevant ID information is excluded from the candidate IDs. . Specifically, when the wheel position is detected based on the acceleration detection signal detected by the acceleration sensor, the vehicle always travels, and therefore the condition of the candidate ID is that the vehicle is traveling. Can do.
 例えば、TPMS-ECU側で車速が所定速度(例えば10km/h)以上であることを確認し、送信機から送信されてきたフレームに加速度センサがオンの状態になったことを示す加速度オンデータ(以下、G-ONデータという)が含まれていることを条件とする。加速度センサは、車輪速度が所定速度に至ると遠心方向の加速度成分が他の成分よりも十分に大きくなって的確な加速度検出が行えるようになる。このように加速度センサが的確な加速度検出が行えるようになったことを加速度センサがオンの状態と言っている。送信機には、加速度センサがオンの状態になったことを検知する機能が備えられており、その検知結果に基づいて、フレーム内にG-ONデータを格納している。逆に、加速度センサがオンの状態になる前は、加速度オフデータ(以下、G-OFFデータという)がフレームに格納される。フレーム内にG-ONデータもしくはG-OFFデータのいずれかを格納して送信することで、TPMS-ECUにおいてG-ONデータが含まれているか否かが判定できる。 For example, on the TPMS-ECU side, it is confirmed that the vehicle speed is a predetermined speed (for example, 10 km / h) or more, and acceleration on data (the acceleration sensor data indicating that the acceleration sensor is turned on in the frame transmitted from the transmitter) (Hereinafter referred to as G-ON data). In the acceleration sensor, when the wheel speed reaches a predetermined speed, the acceleration component in the centrifugal direction becomes sufficiently larger than the other components so that accurate acceleration detection can be performed. The fact that the acceleration sensor can accurately detect the acceleration is referred to as the acceleration sensor being in an on state. The transmitter is provided with a function of detecting that the acceleration sensor is turned on, and G-ON data is stored in the frame based on the detection result. Conversely, before the acceleration sensor is turned on, acceleration off data (hereinafter referred to as G-OFF data) is stored in the frame. By storing and transmitting either G-ON data or G-OFF data in the frame, it is possible to determine whether or not G-ON data is included in the TPMS-ECU.
 このように、G-ONデータが含まれていることを条件とすれば、自車両の走行中以外のときに他車両の送信機のID情報を候補IDを受け付けないようにできる。また、送信機から送られてきたフレームに走行中であることが示されたG-ONデータが含まれていなければ、そのフレームに格納されたID情報も候補IDから除外することができる。これにより、TPMS-ECUのメモリに記憶させられるデータ量の削減を図ることが可能となる。特に、市場に自車両と同一フォーマットの他車両が多くなってくると、送信機の候補IDの数が膨大になり、自車両の車輪のID情報を登録できなくなる可能性があるため、できる限り他車両のID情報が候補IDから除外されるようにするロジックが有用となる。 As described above, if the G-ON data is included, it is possible to prevent the candidate ID from accepting the ID information of the transmitter of the other vehicle when the vehicle is not traveling. If the G-ON data indicating that the vehicle is traveling is not included in the frame sent from the transmitter, the ID information stored in the frame can be excluded from the candidate ID. As a result, the amount of data stored in the memory of the TPMS-ECU can be reduced. In particular, if the number of other vehicles in the same format as the own vehicle increases in the market, the number of candidate IDs of the transmitter becomes enormous and the wheel ID information of the own vehicle may not be registered. Logic that makes ID information of other vehicles excluded from candidate IDs is useful.
 しかしながら、TPMS-ECUが候補IDに含める条件とする所定車速を加速度センサがオン状態となる車速よりも低い値(例えば10km/h)に設定する場合、もしくは、高い値(例えば40km/h)に設定する場合、次のような状況が発生し得る。 However, when the predetermined vehicle speed that the TPMS-ECU includes in the candidate ID is set to a lower value (eg, 10 km / h) than the vehicle speed at which the acceleration sensor is turned on, or a higher value (eg, 40 km / h). When setting, the following situations may occur.
 すなわち、所定車速を低い値に設定した場合、自車両の車速が所定車速よりも大きくなっている際に、まだ加速度センサがオンの状態になっていない速度範囲(10km/h~所定車速の範囲)がある。自車両がこの速度範囲内で走行中に、他車両からのG-ONデータが格納されたフレームが受信されると、そのフレームに格納されたID情報が自車両の車輪の各送信機の候補IDとして登録される。そして、自車両がこの速度範囲内で走行し続けると、他車両のものばかり候補IDに登録されてTPMS-ECUのメモリ容量一杯になり、自車両の車輪の各送信機のID情報が候補IDとして登録されなくなる可能性がある。 That is, when the predetermined vehicle speed is set to a low value, when the vehicle speed of the host vehicle is greater than the predetermined vehicle speed, the speed range in which the acceleration sensor is not turned on yet (range of 10 km / h to the predetermined vehicle speed) ) If a frame storing G-ON data from another vehicle is received while the host vehicle is traveling within this speed range, the ID information stored in the frame is a candidate for each transmitter of the wheels of the host vehicle. Registered as an ID. If the host vehicle continues to travel within this speed range, only those of other vehicles are registered as candidate IDs, and the memory capacity of the TPMS-ECU is filled. May not be registered as.
 また、所定車速を高い値に設定した場合、自車両が常に所定車速を超えない状況で走行していると、上記と同様のことが起こって、自車両の車輪の各送信機のID情報が候補IDとして登録されないという懸念もある。 In addition, when the predetermined vehicle speed is set to a high value, if the own vehicle is always traveling in a state where the predetermined vehicle speed is not exceeded, the same thing as described above occurs, and the ID information of each transmitter of the wheel of the own vehicle is obtained. There is also a concern that it will not be registered as a candidate ID.
 本開示の目的の一つは、上記点に鑑みて、他車両の車輪の送信機のID情報が候補IDとして登録されることを抑制しつつ、自車両の車輪の送信機のID情報が的確に候補IDとして登録される車輪位置検出装置およびそれを備えたタイヤ空気圧検出システムを提供することにある。 One of the objects of the present disclosure is that, in view of the above points, the ID information of the transmitter of the wheel of the own vehicle is accurately determined while suppressing the ID information of the transmitter of the wheel of the other vehicle as a candidate ID. Is to provide a wheel position detection device registered as a candidate ID and a tire air pressure detection system including the same.
 本開示の一観点の車輪位置検出装置は、車体に対してタイヤを備えた複数の車輪が取り付けられた車両に適用される車輪位置検出装置であって、前記複数の車輪それぞれに設けられ、固有の識別情報を含めたフレームを作成すると共に送信する第1制御部を有する送信機と、前記車体側に設けられ、受信アンテナを介して前記送信機から送信されたフレームを受信したのち、該フレームに含まれた前記識別情報のうち登録する候補となる候補識別情報を選別すると共に、該候補識別情報の中から、自車両の前記複数の車輪に設けられた前記送信機と対応するものを特定し、前記複数の車輪と該複数の車輪それぞれに設けられた前記送信機の識別情報とを対応づけて記憶する車輪位置検出を行う第2制御部を有する受信機と、を備える。前記送信機は、該送信機が取り付けられた車輪の回転に伴って変化する重力加速度成分を含む加速度に応じた検出信号を出力する加速度センサを有すると共に、前記第1制御部の機能として、該送信機の取り付けられた車輪の車輪速度が前記加速度センサによる加速度検出が行えるオンの状態となる所定速度に至ったことを検知して、該検知結果に基づいて前記加速度センサの状態を示すデータを前記フレームに格納する機能を有する。前記第1制御部は、該送信機が取り付けられた車輪の中心軸を中心とし、かつ、該車輪の周方向の任意の位置を角度0°として、前記加速度センサの検出信号に含まれる重力加速度成分に基づいて前記送信機の角度を検出すると共に、該角度が所定の送信角度になるタイミングで繰り返し前記フレームを送信させる。前記第2制御部は、前記複数の車輪と連動して回転させられると共に導体とされた歯の部分と前記歯の間に位置する部分が交互に繰り返される磁気抵抗の異なる外周面を有する歯車の歯の通過を検出する車輪速度センサの検出信号に基づいて、前記歯車の歯位置を示す歯車情報を取得すると共に、前記フレームの受信タイミングのときの前記歯位置に基づいて、前記フレームが送信された送信機の取り付けられた車輪を特定して登録することで前記車輪位置検出を行う。前記受信機の前記第2制御部には、前記車両が前記所定速度以上に設定された第1速度以上で走行中の状態であり、かつ、受信した前記フレームに格納された前記加速度センサの状態を示すデータが該加速度センサがオンの状態であるという第1条件を満たすか否かを判定する第1判定部と、前記第1判定部で前記第1条件を満たしていると判定されると、受信した前記フレームに格納された前記識別情報を前記候補識別情報として登録する候補登録部と、前記候補登録部にて登録された前記候補識別情報が含まれるフレームを受信すると、前記車両が前記所定速度未満に設定された第2速度以上で走行中の状態であり、かつ、受信した前記フレームに格納された前記加速度センサの状態を示すデータが、該加速度センサがオンの状態であることを示しているという第2条件を満たすか否かを判定する第2判定部と、前記第2判定部で前記第2条件を満たしていると判定されると、受信した前記フレームの受信タイミングのときの歯位置のデータを前記車輪位置検出に用いる新たなデータとして更新するデータ更新部と、が備えられている。 A wheel position detection device according to an aspect of the present disclosure is a wheel position detection device applied to a vehicle in which a plurality of wheels including tires are attached to a vehicle body, and is provided on each of the plurality of wheels. A transmitter including a first control unit that generates and transmits a frame including the identification information of the frame, and a frame that is provided on the vehicle body side and receives the frame transmitted from the transmitter via a reception antenna. And selecting candidate identification information to be registered from among the identification information included in the vehicle, and identifying one corresponding to the transmitter provided on the plurality of wheels of the host vehicle from the candidate identification information And a receiver having a second control unit that performs wheel position detection that stores the plurality of wheels and the identification information of the transmitter provided in each of the plurality of wheels in association with each other. The transmitter includes an acceleration sensor that outputs a detection signal corresponding to an acceleration including a gravitational acceleration component that changes with rotation of a wheel to which the transmitter is attached, and as a function of the first control unit, Detecting that the wheel speed of the wheel to which the transmitter is attached has reached a predetermined speed at which the acceleration sensor can detect the acceleration, and indicating the state of the acceleration sensor based on the detection result It has a function of storing in the frame. The first control unit has a gravitational acceleration included in the detection signal of the acceleration sensor with the central axis of the wheel to which the transmitter is attached as the center and an arbitrary position in the circumferential direction of the wheel as an angle of 0 °. The angle of the transmitter is detected based on the component, and the frame is repeatedly transmitted at a timing at which the angle becomes a predetermined transmission angle. The second control unit is a gear having an outer peripheral surface having different magnetic resistances, which is rotated in conjunction with the plurality of wheels, and a portion of a tooth which is a conductor and a portion located between the teeth are alternately repeated. Based on the detection signal of the wheel speed sensor that detects the passage of teeth, gear information indicating the tooth position of the gear is acquired, and the frame is transmitted based on the tooth position at the reception timing of the frame. The wheel position is detected by identifying and registering the wheel to which the transmitter is attached. The second control unit of the receiver is in a state where the vehicle is traveling at a first speed or higher set to be equal to or higher than the predetermined speed, and the state of the acceleration sensor stored in the received frame A first determination unit that determines whether or not the first condition that the acceleration sensor is on is satisfied, and the first determination unit determines that the first condition is satisfied. When the candidate registration unit that registers the identification information stored in the received frame as the candidate identification information and the frame that includes the candidate identification information registered by the candidate registration unit are received, the vehicle The data indicating the state of the acceleration sensor stored in the received frame is the state in which the acceleration sensor is on, and the vehicle is traveling at the second speed or higher set below the predetermined speed. A second determination unit that determines whether or not the second condition is satisfied, and the reception timing of the received frame when the second determination unit determines that the second condition is satisfied And a data updating unit for updating the tooth position data as new data used for the wheel position detection.
 このように、候補識別情報を登録する際に、登録条件を厳しくすることで登録される識別情報の数を絞りつつ、一旦、候補識別情報として登録された識別情報については、データ更新がされ易くなるようにしている。具体的には、登録条件として用いている車両状態が走行中であることの判定基準を、加速度センサがオンの状態となっている第1速度以上の車速が発生していることとしている。そして、データ更新の条件として用いている車両状態が走行中であることの判定基準を、第1速度よりも低い第2速度以上の車速が発生していることとしている。 As described above, when registering candidate identification information, the number of pieces of identification information to be registered is reduced by tightening the registration conditions, and the identification information once registered as candidate identification information is easily updated. It is trying to become. Specifically, a criterion for determining that the vehicle state used as the registration condition is running is that a vehicle speed equal to or higher than the first speed at which the acceleration sensor is on is generated. The criterion for determining that the vehicle state used as the data update condition is running is that a vehicle speed equal to or higher than the second speed that is lower than the first speed is generated.
 このように、登録条件を厳しくすることで、候補識別情報として選別される識別情報の数を絞り、受信機のメモリ容量が一杯になることを抑制することができる。したがって、他車両の車輪の送信機の識別情報が候補識別情報として登録されることを抑制しつつ、自車両の車輪の送信機の識別情報が的確に候補識別情報として登録されるようにできる。また、データ更新の条件を登録条件よりも緩くすることで、候補識別情報についてのデータ更新がされ易くなるようにできる。 Thus, by tightening the registration conditions, it is possible to reduce the number of pieces of identification information selected as candidate identification information and suppress the memory capacity of the receiver from becoming full. Accordingly, it is possible to accurately register the identification information of the transmitter of the wheel of the host vehicle as the candidate identification information while suppressing the identification information of the transmitter of the wheel of the other vehicle from being registered as the candidate identification information. Further, by making the data update condition looser than the registration condition, it is possible to easily update the data regarding the candidate identification information.
 本開示の一観点のタイヤ空気圧検出システムは、上述の車輪位置検出装置を含むタイヤ空気圧検出システムであって、前記送信機は、前記複数の車輪それぞれに備えられた前記タイヤの空気圧に応じた検出信号を出力するセンシング部を備え、前記第1制御部によって前記センシング部の検出信号を信号処理したタイヤ空気圧に関する情報をフレームに格納したのち、当該フレームを前記受信機に送信し、前記受信機は、前記第2制御部にて、該タイヤ空気圧に関する情報より、前記複数の車輪それぞれに備えられた前記タイヤの空気圧を検出する。 A tire air pressure detection system according to an aspect of the present disclosure is a tire air pressure detection system including the wheel position detection device described above, wherein the transmitter detects according to the air pressure of the tire provided in each of the plurality of wheels. A sensing unit for outputting a signal, and storing information on tire pressure obtained by signal processing of the detection signal of the sensing unit by the first control unit in a frame, and then transmitting the frame to the receiver. The second control unit detects the air pressure of the tire provided in each of the plurality of wheels from the information related to the tire air pressure.
 本開示についての上記および他の目的、特徴や利点は、添付図面を参照した下記の詳細な説明から、より明確になる。添付図面において
図1は、第1実施形態にかかる車輪位置検出装置が適用されるタイヤ空気圧検出装置の全体構成を示す図である。 図2Aは、送信機のブロック構成を示す図である。 図2Bは、TPMS-ECUのブロック構成を示す図である。 図3は、車輪位置検出を説明するためのタイミングチャートである。 図4は、歯車情報の変化を示したイメージ図である。 図5Aは、車輪位置確定ロジックを図解した模式図である。 図5Bは、車輪位置確定ロジックを図解した模式図である。 図5Cは、車輪位置確定ロジックを図解した模式図である。 図6Aは、ID1の車輪位置の評価結果を示した図表である。 図6Bは、ID2の車輪位置の評価結果を示した図表である。 図6Cは、ID3の車輪位置の評価結果を示した図表である。 図6Dは、ID4の車輪位置の評価結果を示した図表である。 図7は、候補ID登録処理のフローチャートである。 図8は、データ更新処理のフローチャートである。
The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. In the attached drawings
FIG. 1 is a diagram illustrating an overall configuration of a tire air pressure detection device to which the wheel position detection device according to the first embodiment is applied. FIG. 2A is a diagram illustrating a block configuration of the transmitter. FIG. 2B is a diagram showing a block configuration of the TPMS-ECU. FIG. 3 is a timing chart for explaining wheel position detection. FIG. 4 is an image diagram showing changes in gear information. FIG. 5A is a schematic diagram illustrating wheel position determination logic. FIG. 5B is a schematic diagram illustrating the wheel position determination logic. FIG. 5C is a schematic diagram illustrating the wheel position determination logic. FIG. 6A is a chart showing the evaluation result of the wheel position of ID1. FIG. 6B is a chart showing the evaluation result of the wheel position of ID2. FIG. 6C is a chart showing the evaluation result of the wheel position of ID3. FIG. 6D is a chart showing the evaluation result of the wheel position of ID4. FIG. 7 is a flowchart of candidate ID registration processing. FIG. 8 is a flowchart of the data update process.
 以下、実施形態について図に基づいて説明する。なお、以下の各実施形態相互において、互いに同一もしくは均等である部分には、同一符号を付して説明を行う。 Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.
 (第1実施形態)
 第1実施形態について図を参照して説明する。図1は、第1実施形態における車輪位置検出装置が適用されるTPMSの全体構成を示す図である。図1の紙面上方向が車両1の前方、紙面下方向が車両1の後方に一致する。この図を参照して、本実施形態におけるTPMSについて説明する。
(First embodiment)
A first embodiment will be described with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of a TPMS to which the wheel position detection device according to the first embodiment 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, TPMS in this embodiment is demonstrated.
 図1に示すように、TPMSは、車両1に備えられるもので、送信機2、受信機の役割を果たすTPMS用のECU(以下、TPMS-ECUという)3およびメータ4を備えて構成されている。車輪位置検出装置は、TPMSに備えられる送信機2およびTPMS-ECU3を用いると共に、ブレーキ制御用ECU(以下、ブレーキECUという)10から各車輪5(5a~5d)に対応して備えられた車輪速度センサ11a~11dの検出信号から得られる歯車情報を取得することで、車輪位置の特定を行っている。 As shown in FIG. 1, the TPMS is provided in the vehicle 1, and includes a transmitter 2, an ECU for TPMS (hereinafter referred to as TPMS-ECU) 3 serving as a receiver, and a meter 4. Yes. The wheel position detection device uses a transmitter 2 and a TPMS-ECU 3 provided in the TPMS, and wheels provided corresponding to each wheel 5 (5a to 5d) from a brake control ECU (hereinafter referred to as a brake ECU) 10. The wheel position is specified by acquiring gear information obtained from detection signals of the speed sensors 11a to 11d.
 図1に示すように、送信機2は、各車輪5a~5dに取り付けられるもので、車輪5a~5dに取り付けられたタイヤの空気圧を検出すると共に、その検出結果を示すタイヤ空気圧に関する情報を各送信機2の固有のID情報と共にフレーム内に格納して送信する。また、フレーム内には、後述する加速度センサ22がオンの状態になったことを示すG-ONデータもしくはオンの状態になっていないことを示すG-OFFデータが格納される。これらG-ONデータおよびG-OFFデータが加速度センサ22の状態を示すデータに相当する。加速度センサ22は、常に加速度検出を行っているものの、車輪速度が所定速度に至ると遠心方向の加速度成分が他の成分よりも十分に大きくなって的確な加速度検出が行えるようになる。このように加速度センサ22が的確な加速度検出が行えるようになったことを加速度センサ22がオンの状態と言っている。送信機2には、加速度センサ22がオンの状態になったことを検知する機能が備えられており、その検知結果に基づいて、フレーム内にG-ONデータもしくはG-OFFデータを格納している。例えば、送信機2には、遠心方向の加速度に応じて変位する可動接点が固定接点に接する物理スイッチ(図示せず)が備えられており、この物理スイッチがオンして導通すると、加速度センサ22がオンの状態になったと検知している。 As shown in FIG. 1, the transmitter 2 is attached to each of the wheels 5a to 5d, detects the air pressure of the tire attached to the wheels 5a to 5d, and provides information about the tire air pressure indicating the detection result. It is stored in a frame together with the unique ID information of the transmitter 2 and transmitted. In the frame, G-ON data indicating that an acceleration sensor 22 (described later) is turned on or G-OFF data indicating that the acceleration sensor 22 is not turned on is stored. These G-ON data and G-OFF data correspond to data indicating the state of the acceleration sensor 22. Although the acceleration sensor 22 always detects acceleration, when the wheel speed reaches a predetermined speed, the acceleration component in the centrifugal direction becomes sufficiently larger than the other components so that accurate acceleration detection can be performed. The fact that the acceleration sensor 22 can perform accurate acceleration detection in this way is referred to as the acceleration sensor 22 being in an on state. The transmitter 2 has a function of detecting that the acceleration sensor 22 is turned on, and stores G-ON data or G-OFF data in a frame based on the detection result. Yes. For example, the transmitter 2 is provided with a physical switch (not shown) in which a movable contact that is displaced according to acceleration in the centrifugal direction is in contact with a fixed contact. Is detected to have been turned on.
 一方、TPMS-ECU3は、車両1における車体6側に取り付けられるもので、送信機2から送信されたフレームを受信すると共に、その中に格納された検出信号に基づいて各種処理や演算等を行うことで車輪位置検出およびタイヤ空気圧検出を行う。 On the other hand, the TPMS-ECU 3 is attached to the vehicle body 6 side of the vehicle 1 and receives the frame transmitted from the transmitter 2 and performs various processes and calculations based on the detection signal stored therein. Thus, wheel position detection and tire air pressure detection are performed.
 送信機2は、例えばFSK(周波数偏移変調)によりフレームを作成し、TPMS-ECU3は、そのフレームを復調することでフレーム内のデータを読取り、車輪位置検出およびタイヤ空気圧検出を行っている。図2A、図2Bに送信機2およびTPMS-ECU3のブロック構成を示す。 The transmitter 2 creates a frame by, for example, FSK (frequency shift keying), and the TPMS-ECU 3 demodulates the frame to read data in the frame to detect the wheel position and the tire air pressure. 2A and 2B show block configurations of the transmitter 2 and the TPMS-ECU 3.
 図2Aに示すように、送信機2は、センシング部21、加速度センサ22、マイクロコンピュータ23、送信回路24および送信アンテナ25を備えた構成となっており、図示しない電池からの電力供給に基づいて各部が駆動される。 As shown in FIG. 2A, the transmitter 2 includes a sensing unit 21, an acceleration sensor 22, a microcomputer 23, a transmission circuit 24, and a transmission antenna 25, and is based on power supply from a battery (not shown). Each part is driven.
 センシング部21は、例えばダイアフラム式の圧力センサ21aや温度センサ21bを備えた構成とされ、タイヤ空気圧に応じた検出信号や温度に応じた検出信号を出力する。加速度センサ22は、送信機2が取り付けられた車輪5a~5dでのセンサ自身の位置検出、つまり送信機2の位置検出や車速検出を行うために用いられる。本実施形態の加速度センサ22は、例えば、車輪5a~5dの回転時に車輪5a~5dに働く加速度のうち、各車輪5a~5dの径方向、つまり周方向に垂直な両方向の加速度に応じた検出信号を出力する。 The sensing unit 21 includes a diaphragm type pressure sensor 21a and a temperature sensor 21b, for example, and outputs a detection signal corresponding to the tire pressure and a detection signal corresponding to the temperature. The acceleration sensor 22 is used to detect the position of the sensor itself at the wheels 5a to 5d to which the transmitter 2 is attached, that is, to detect the position of the transmitter 2 and the vehicle speed. The acceleration sensor 22 according to the present embodiment detects, for example, acceleration corresponding to accelerations in both directions perpendicular to the radial direction of each wheel 5a to 5d, that is, the circumferential direction, among the accelerations acting on the wheels 5a to 5d when the wheels 5a to 5d rotate. Output a signal.
 マイクロコンピュータ23は、制御部(第1制御部)などを備えた周知のもので、制御部内のメモリに記憶されたプログラムに従って、所定の処理を実行する。制御部内のメモリには、各送信機2を特定するための送信機固有の識別情報と自車両を特定するための車両固有の識別情報とを含む個別のID情報が格納されている。 The microcomputer 23 is a well-known one having a control unit (first control unit) and the like, and executes predetermined processing according to a program stored in a memory in the control unit. Individual ID information including identification information unique to the transmitter for identifying each transmitter 2 and identification information unique to the vehicle for identifying the host vehicle is stored in the memory in the control unit.
 マイクロコンピュータ23は、センシング部21からのタイヤ空気圧に関する検出信号を受け取り、それを信号処理すると共に必要に応じて加工し、そのタイヤ空気圧に関する情報を各送信機2のID情報と共にフレーム内に格納する。また、マイクロコンピュータ23は、加速度センサ22の検出信号をモニタし、各送信機2が取り付けられた車輪5a~5dでの送信機2の位置検出(角度検出)を行ったり、車速検出を行っている。そして、マイクロコンピュータ23は、フレームを作成すると、送信機2の位置検出の結果や車速検出の結果に基づいて、送信回路24を介して送信アンテナ25よりTPMS-ECU3に向けてフレーム送信(データ送信)を行う。 The microcomputer 23 receives the detection signal related to the tire pressure from the sensing unit 21, processes the signal and processes it as necessary, and stores the information related to the tire pressure in the frame together with the ID information of each transmitter 2. . Further, the microcomputer 23 monitors the detection signal of the acceleration sensor 22 to detect the position (angle detection) of the transmitter 2 on the wheels 5a to 5d to which the transmitters 2 are attached, or to detect the vehicle speed. Yes. When the microcomputer 23 creates the frame, the microcomputer 23 transmits the frame (data transmission) from the transmission antenna 25 to the TPMS-ECU 3 via the transmission circuit 24 based on the position detection result of the transmitter 2 and the vehicle speed detection result. )I do.
 具体的には、マイクロコンピュータ23は、車両1が走行中であることを条件としてフレーム送信を開始しており、加速度センサ22の検出信号に基づいて加速度センサ22の角度が所定角度になるタイミングで繰り返しフレーム送信を行っている。走行中であることについては、車速検出の結果に基づいて判定しており、加速度センサ22の角度については加速度センサ22の検出信号に基づく送信機2の位置検出の結果に基づいて判定している。 Specifically, the microcomputer 23 starts frame transmission on the condition that the vehicle 1 is traveling, and at a timing at which the angle of the acceleration sensor 22 becomes a predetermined angle based on the detection signal of the acceleration sensor 22. Repeated frame transmission. Whether the vehicle is running is determined based on the vehicle speed detection result, and the angle of the acceleration sensor 22 is determined based on the position detection result of the transmitter 2 based on the detection signal of the acceleration sensor 22. .
 すなわち、マイクロコンピュータ23で加速度センサ22の検出信号を利用して車速検出を行い、車速が所定速度(例えば5km/h)以上になると車両1が走行中であると判定している。加速度センサ22の出力には遠心力に基づく加速度(遠心加速度)が含まれる。この遠心加速度を積分して係数を掛けることにより、車速を演算することが可能となる。このため、マイクロコンピュータ23では、加速度センサ22の出力から重力加速度成分を取り除いて遠心加速度を演算し、その遠心加速度に基づいて車速の演算を行っている。 That is, the microcomputer 23 detects the vehicle speed using the detection signal of the acceleration sensor 22, and determines that the vehicle 1 is running when the vehicle speed becomes a predetermined speed (for example, 5 km / h) or more. The output of the acceleration sensor 22 includes acceleration based on centrifugal force (centrifugal acceleration). The vehicle speed can be calculated by integrating the centrifugal acceleration and multiplying the coefficient. For this reason, the microcomputer 23 calculates the centrifugal acceleration by removing the gravitational acceleration component from the output of the acceleration sensor 22, and calculates the vehicle speed based on the centrifugal acceleration.
 また、加速度センサ22によって各車輪5a~5dの回転に応じた検出信号を出力させていることから、走行時には、その検出信号に重力加速度成分が含まれることになり、車輪回転に応じた振幅を有する信号となる。例えば、検出信号の振幅は、送信機2が車輪5a~5dの中心軸を中心として上方位置に位置しているときには負の最大振幅、水平位置に位置しているときにはゼロ、下方位置に位置しているときには正の最大振幅となる。このため、この振幅に基づいて加速度センサ22の位置検出を行え、送信機2の位置の角度、例えば各車輪5a~5dの中心軸を中心として、加速度センサ22が上方位置に位置しているときを0°としたときの加速度センサ22の成す角度を把握できる。 Since the acceleration sensor 22 outputs detection signals corresponding to the rotations of the wheels 5a to 5d, the gravitational acceleration component is included in the detection signals during traveling, and the amplitude corresponding to the wheel rotation is increased. Signal. For example, the amplitude of the detection signal is the negative maximum amplitude when the transmitter 2 is located at the upper position around the central axis of the wheels 5a to 5d, zero when located at the horizontal position, and located at the lower position. The maximum positive amplitude is obtained. Therefore, the position of the acceleration sensor 22 can be detected based on this amplitude, and when the acceleration sensor 22 is located at an upper position around the angle of the position of the transmitter 2, for example, the central axis of each wheel 5a to 5d. It is possible to grasp the angle formed by the acceleration sensor 22 when the angle is set to 0 °.
 したがって、車速が所定速度に達すると同時もしくは車速が所定速度に達したのち加速度センサ22が所定角度になったときを開始タイミングとして、各送信機2からのフレーム送信を行うようにしている。そして、加速度センサ22の成す角度が1回目のフレーム送信のときと同じ角度になるタイミングに、それを送信タイミングとして繰り返しフレーム送信を行うようにしている。なお、送信タイミングについては、加速度センサ22の成す角度が1回目のフレーム送信のときと同じ角度になる毎としても良いが、電池寿命を考慮して、その角度になる毎に常にフレーム送信を行わず、例えば所定時間(例えば15秒間)に1回のみフレーム送信を行うようにすると好ましい。 Therefore, the frame transmission from each transmitter 2 is performed at the start timing when the acceleration sensor 22 reaches a predetermined angle at the same time when the vehicle speed reaches the predetermined speed or after the vehicle speed reaches the predetermined speed. The frame is transmitted repeatedly at the timing when the angle formed by the acceleration sensor 22 becomes the same angle as the first frame transmission. Regarding the transmission timing, the angle formed by the acceleration sensor 22 may be the same as that at the time of the first frame transmission. However, in consideration of the battery life, the frame transmission is always performed every time the angle is reached. For example, it is preferable that frame transmission is performed only once in a predetermined time (for example, 15 seconds).
 送信回路24は、送信アンテナ25を通じて、マイクロコンピュータ23から送られてきたフレームをTPMS-ECU3に向けて送信する出力部としての機能を果たす。フレーム送信には、例えばRF帯の電波を用いている。 The transmission circuit 24 functions as an output unit that transmits a frame transmitted from the microcomputer 23 to the TPMS-ECU 3 through the transmission antenna 25. For frame transmission, for example, radio waves in the RF band are used.
 このように構成される送信機2は、例えば、各車輪5a~5dのホイールにおけるエア注入バルブに取り付けられ、センシング部21がタイヤの内側に露出するように配置される。そして、送信機2は、送信機2が取り付けられた車輪のタイヤ空気圧を検出し、上記したように車速が所定速度を超えると、各車輪5a~5dの加速度センサ22の角度が所定角度になるタイミングで繰り返し各送信機2に備えられた送信アンテナ25を通じてフレーム送信を行う。その後も、送信機2から各車輪5a~5dの加速度センサ22の角度が所定角度になるタイミングでフレーム送信を行うようにすることもできるが、電池寿命を考慮して送信間隔を長くした方が良いため、車輪位置検出に必要と想定される時間が経過すると車輪位置確定モードから定期送信モードに切り替わり、より長い一定周期毎(例えば1分毎)にフレーム送信を行うことで、TPMS-ECU3側にタイヤ空気圧に関する信号を定期送信する。このとき、例えば送信機2毎にランダムディレイを設けることで、各送信機2の送信タイミングがずれるようにすることができ、複数の送信機2からの電波の混信によってTPMS-ECU3側で受信できなくなることを防止することができる。 The transmitter 2 configured in this way is attached to an air injection valve in each of the wheels 5a to 5d, for example, and is arranged so that the sensing unit 21 is exposed inside the tire. The transmitter 2 detects the tire air pressure of the wheel to which the transmitter 2 is attached, and when the vehicle speed exceeds a predetermined speed as described above, the angle of the acceleration sensor 22 of each wheel 5a to 5d becomes a predetermined angle. Frame transmission is performed repeatedly through the transmission antenna 25 provided in each transmitter 2 at the timing. After that, it is possible to perform frame transmission from the transmitter 2 at the timing at which the angle of the acceleration sensor 22 of each wheel 5a to 5d becomes a predetermined angle, but it is better to increase the transmission interval in consideration of the battery life. For this reason, when the time assumed to be necessary for wheel position detection elapses, the mode is switched from the wheel position determination mode to the periodic transmission mode, and frame transmission is performed at a longer fixed period (for example, every minute), so that the TPMS-ECU3 side A signal related to the tire pressure is periodically transmitted to. At this time, for example, by providing a random delay for each transmitter 2, the transmission timing of each transmitter 2 can be shifted, and reception by the TPMS-ECU 3 side due to radio wave interference from a plurality of transmitters 2 is possible. It can be prevented from disappearing.
 また、図2Bに示すように、TPMS-ECU3は、受信アンテナ31、受信回路32およびマイクロコンピュータ33などを備えた構成とされている。TPMS-ECU3は、CANなどの車内LANを通じて、後述するようにブレーキECU10から歯車情報を取得することで各車輪5a~5dと共に回転させられる歯車の歯のエッジ数(もしくは歯数)で示される歯位置を取得している。 Further, as shown in FIG. 2B, the TPMS-ECU 3 includes a receiving antenna 31, a receiving circuit 32, a microcomputer 33, and the like. The TPMS-ECU 3 acquires the gear information from the brake ECU 10 through an in-vehicle LAN such as CAN as will be described later, and the teeth indicated by the number of teeth (or the number of teeth) of the gears rotated together with the wheels 5a to 5d. Get the position.
 受信アンテナ31は、各送信機2から送られてくるフレームを受信するためのものである。受信アンテナ31は、車体6に固定されており、TPMS-ECU3の本体内に配置された内部アンテナでも良いし、本体から配線を引き伸ばした外部アンテナとされていても良い。 The receiving antenna 31 is for receiving a frame sent from each transmitter 2. The receiving antenna 31 is fixed to the vehicle body 6 and may be an internal antenna disposed in the main body of the TPMS-ECU 3, or may be an external antenna in which wiring is extended from the main body.
 受信回路32は、受信アンテナ31によって受信された各送信機2からの送信フレームを入力し、そのフレームをマイクロコンピュータ33に送る入力部としての機能を果たす。受信回路32は、受信アンテナ31を通じて信号(フレーム)を受信すると、その受信した信号をマイクロコンピュータ33に伝えている。 The receiving circuit 32 functions as an input unit that receives a transmission frame from each transmitter 2 received by the receiving antenna 31 and sends the frame to the microcomputer 33. When receiving a signal (frame) through the receiving antenna 31, the receiving circuit 32 transmits the received signal to the microcomputer 33.
 マイクロコンピュータ33は、第2制御部に相当するもので、マイクロコンピュータ33内のメモリに記憶されたプログラムに従って車輪位置検出を実行する。具体的には、マイクロコンピュータ33は、ブレーキECU10から取得する情報と、各送信機2からの送信フレームを受信した受信タイミングとの関係に基づいて車輪位置検出を行っている。ブレーキECU10からは、各車輪5a~5dの車輪速度情報に加えて各車輪5a~5dに対応して備えられた車輪速度センサ11a~11dの歯車情報を所定周期(例えば10ms)毎に取得している。 The microcomputer 33 corresponds to the second control unit, and executes wheel position detection according to a program stored in a memory in the microcomputer 33. Specifically, the microcomputer 33 performs wheel position detection based on the relationship between the information acquired from the brake ECU 10 and the reception timing at which the transmission frame from each transmitter 2 is received. From the brake ECU 10, in addition to the wheel speed information of the wheels 5a to 5d, gear information of the wheel speed sensors 11a to 11d provided corresponding to the wheels 5a to 5d is acquired every predetermined period (for example, 10 ms). Yes.
 歯車情報とは、各車輪5a~5dと共に回転させられる歯車(ギア)の歯位置を示す情報である。車輪速度センサ11a~11dは、例えば歯車の歯に対向して配置される電磁ピックアップ式センサによって構成され、歯車の歯の通過に伴って検出信号を変化させる。このようなタイプの車輪速度センサ11a~11dでは、検出信号として歯の通過に対応する方形パルス波を出力していることから、その方形パルス波の立上りおよび立下りが歯車の歯のエッジの通過を表すことになる。したがって、ブレーキECU10では、車輪速度センサ11a~11dの検出信号の立上りおよび立下りの数から歯車の歯のエッジ数、つまりエッジの通過数をカウントし、所定周期毎に、そのときの歯のエッジ数を、歯位置を示す歯車情報としてマイクロコンピュータ33に伝えている。これにより、マイクロコンピュータ33では、歯車のどの歯が通過したタイミングであるかを把握することが可能になっている。 Gear information is information indicating the tooth positions of gears (gears) that are rotated together with the wheels 5a to 5d. The wheel speed sensors 11a to 11d are constituted by, for example, electromagnetic pickup sensors arranged to face the gear teeth, and change the detection signal as the gear teeth pass. Since these types of wheel speed sensors 11a to 11d output square pulse waves corresponding to the passage of teeth as detection signals, the rising and falling of the square pulse waves pass through the tooth edge of the gear. Will be expressed. Therefore, the brake ECU 10 counts the number of teeth of the gear, that is, the number of passing edges, from the number of rising and falling edges of the detection signals of the wheel speed sensors 11a to 11d, and the tooth edge at that time is counted every predetermined period. The number is transmitted to the microcomputer 33 as gear information indicating the tooth position. Thereby, in the microcomputer 33, it is possible to grasp which tooth of the gear has passed.
 歯のエッジ数は、歯車が1回転する毎にリセットされる。例えば、歯車に備えられた歯の数が48歯である場合、エッジ数は0~95の合計96個でカウントされ、カウント値が95に至ると再び0に戻ってカウントされる。 歯 The number of tooth edges is reset every time the gear rotates once. For example, when the number of teeth provided on the gear is 48 teeth, the number of edges is counted as a total of 96 from 0 to 95, and when the count value reaches 95, it is returned to 0 and counted again.
 なお、ここではブレーキECU10から歯車情報として歯車の歯のエッジ数をマイクロコンピュータ33に伝えるようにしたが、歯の通過数のカウント値である歯数であっても良い。また、所定周期の間に通過したエッジ数もしくは歯数をマイクロコンピュータ33に伝え、マイクロコンピュータ33で前回までのエッジ数もしくは歯数に所定周期の間に通過したエッジ数もしくは歯数を加算させ、その周期でのエッジ数もしくは歯数をカウントさせるようにしても良い。つまり、マイクロコンピュータ33で最終的に歯車情報としてその周期でのエッジ数もしくは歯数が取得できれば良い。また、ブレーキECU10では、歯車の歯のエッジ数(もしくは歯数)を電源オフのたびにリセットすることになるが、電源オンすると同時もしくは電源オンしてから所定車速になったときから再び計測している。このように、電源オフのたびにリセットされたとしても、電源オン中には同じ歯が同じエッジ数(もしくは歯数)で表されることになる。 In this case, the number of tooth edges of the gear is transmitted from the brake ECU 10 to the microcomputer 33 as gear information. However, the number of teeth may be a count value of the number of passing teeth. Further, the number of edges or teeth passed during the predetermined period is transmitted to the microcomputer 33, and the microcomputer 33 adds the number of edges or teeth passed during the predetermined period to the previous number of edges or teeth. You may make it count the number of edges or the number of teeth in the period. That is, it is only necessary that the microcomputer 33 can finally acquire the number of edges or the number of teeth in the cycle as gear information. The brake ECU 10 resets the number of gear teeth (or the number of teeth) every time the power is turned off, but again starts measuring at the same time when the power is turned on or when the vehicle speed reaches the predetermined vehicle speed. ing. Thus, even if the power is turned off every time the power is turned off, the same teeth are represented by the same number of edges (or the number of teeth) while the power is turned on.
 そして、マイクロコンピュータ33は、各送信機2から送信されたフレームを受信したときにその受信タイミングを計測し、取得している歯車のエッジ数(もしくは歯数)の中からフレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)に基づいて車輪位置検出を行っている。これにより、各送信機2がどの車輪5a~5dに取り付けられたものかを特定する車輪位置検出を行うことが可能となる。この車輪位置検出の具体的な方法については後で詳細に説明する。 The microcomputer 33 measures the reception timing when the frame transmitted from each transmitter 2 is received, and the frame reception timing is determined from the number of edges (or the number of teeth) of the acquired gear. The wheel position is detected based on the number of edges (or the number of teeth) of the gear. As a result, it is possible to perform wheel position detection that specifies to which wheel 5a to 5d each transmitter 2 is attached. A specific method for detecting the wheel position will be described in detail later.
 また、マイクロコンピュータ33は、車輪位置検出の結果に基づいて、各送信機2のID情報と各送信機2が取り付けられている各車輪5a~5dの位置とを関連づけて記憶する。そして、その後は各送信機2からの送信フレーム内に格納されたID情報およびタイヤ空気圧に関するデータに基づいて、各車輪5a~5dのタイヤ空気圧検出を行い、タイヤ空気圧に応じた電気信号をCANなどの車内LANを通じてメータ4に出力する。例えば、マイクロコンピュータ33は、タイヤ空気圧を所定のしきい値Thと比較することでタイヤ空気圧の低下を検知し、タイヤ空気圧の低下を検知するとその旨の信号をメータ4に出力する。これにより、4つの車輪5a~5dのいずれかのタイヤ空気圧が低下したことがメータ4に伝えられる。 Further, the microcomputer 33 stores the ID information of each transmitter 2 in association with the position of each wheel 5a to 5d to which each transmitter 2 is attached based on the result of wheel position detection. After that, based on the ID information and tire pressure data stored in the transmission frame from each transmitter 2, the tire pressure of each wheel 5a to 5d is detected, and an electrical signal corresponding to the tire pressure is sent to CAN or the like. Is output to the meter 4 through the in-vehicle LAN. For example, the microcomputer 33 detects a decrease in tire air pressure by comparing the tire air pressure with a predetermined threshold Th, and outputs a signal to that effect to the meter 4 when a decrease in tire air pressure is detected. As a result, the meter 4 is informed that the tire air pressure of any of the four wheels 5a to 5d has decreased.
 メータ4は、警報部として機能するものであり、図1に示されるように、ドライバが視認可能な場所に配置され、例えば車両1におけるインストルメントパネル内に設置されるメータディスプレイ等によって構成される。このメータ4は、例えばTPMS-ECU3におけるマイクロコンピュータ33からタイヤ空気圧が低下した旨を示す信号が送られてくると、車輪5a~5dを特定しつつタイヤ空気圧の低下を示す表示を行うことでドライバに特定車輪のタイヤ空気圧の低下を報知する。 The meter 4 functions as an alarm unit, and as shown in FIG. 1, is arranged at a place where the driver can visually recognize, and is configured by a meter display or the like 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 microcomputer 33 in the TPMS-ECU 3, the meter 4 displays a decrease in tire air pressure while identifying the wheels 5a to 5d. Informs that the tire pressure of the specific wheel has decreased.
 続いて、本実施形態のTPMSの作動について説明する。以下、TPMSの作動について説明するが、TPMSで行われる車輪位置検出とタイヤ空気圧検出とに分けて説明する。まず、図3~図6Dを参照して車輪位置検出の具体的な方法を説明する。 Subsequently, the operation of the TPMS of this embodiment will be described. Hereinafter, although the operation of the TPMS will be described, the description will be divided into wheel position detection and tire air pressure detection performed by the TPMS. First, a specific method of wheel position detection will be described with reference to FIGS. 3 to 6D.
 送信機2側では、マイクロコンピュータ23が電池からの電力供給に基づいて所定のサンプリング周期毎に加速度センサ22の検出信号をモニタすることで車速および車輪5a~5dそれぞれでの加速度センサ22の角度を検出している。そして、マイクロコンピュータ23は、車速が所定速度に達すると、加速度センサ22の角度が所定角度になるタイミングで繰り返しフレーム送信を行う。例えば、車速が所定速度に達した時を所定角度として、もしくは車速が所定速度に達したのち加速度センサ22が所定角度になったときを開始タイミングとして、各送信機2からのフレーム送信を行うようにしている。そして、加速度センサ22の成す角度が1回目のフレーム送信のときと同じ角度になるタイミングに、それを送信タイミングとして繰り返しフレーム送信を行うようにしている。 On the transmitter 2 side, the microcomputer 23 monitors the detection signal of the acceleration sensor 22 at every predetermined sampling period based on the power supply from the battery, thereby determining the vehicle speed and the angle of the acceleration sensor 22 at each of the wheels 5a to 5d. Detected. Then, when the vehicle speed reaches a predetermined speed, the microcomputer 23 repeatedly transmits frames at a timing at which the angle of the acceleration sensor 22 becomes a predetermined angle. For example, frame transmission from each transmitter 2 is performed with a predetermined angle when the vehicle speed reaches a predetermined speed or a start timing when the acceleration sensor 22 reaches a predetermined angle after the vehicle speed reaches the predetermined speed. I have to. The frame is transmitted repeatedly at the timing when the angle formed by the acceleration sensor 22 becomes the same angle as the first frame transmission.
 すなわち、加速度センサ22の検出信号の重力加速度成分を抽出すると、図3に示すようなsin波となる。このsin波に基づいて加速度センサ22の角度が分かる。このため、sin波に基づいて加速度センサ22が同じ角度になるタイミングで、フレーム送信を行うようにしている。 That is, when the gravitational acceleration component of the detection signal of the acceleration sensor 22 is extracted, a sin wave as shown in FIG. 3 is obtained. Based on this sine wave, the angle of the acceleration sensor 22 is known. For this reason, frame transmission is performed at the timing at which the acceleration sensor 22 has the same angle based on the sin wave.
 一方、TPMS-ECU3側では、ブレーキECU10から各車輪5a~5dに対応して備えられた車輪速度センサ11a~11dの歯車情報を所定周期(例えば10ms)毎に取得している。そして、TPMS-ECU3は、各送信機2から送信されたフレームを受信したときにその受信タイミングを計測し、取得している歯車のエッジ数(もしくは歯数)の中からフレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)を取得する。 On the other hand, on the TPMS-ECU 3 side, the gear information of the wheel speed sensors 11a to 11d provided corresponding to the wheels 5a to 5d is acquired from the brake ECU 10 at predetermined intervals (for example, 10 ms). Then, the TPMS-ECU 3 measures the reception timing when the frame transmitted from each transmitter 2 is received, and when the frame reception timing is selected from the number of gear edges (or the number of teeth). Get the number of gear edges (or the number of teeth).
 このとき、各送信機2から送信されたフレームの受信タイミングとブレーキECU10から歯車情報を取得している周期とが一致するとは限らない。このため、ブレーキECU10から歯車情報を取得した周期の中からフレームの受信タイミングに最も近い周期、つまりその直前または直後の周期に取得した歯車情報が示す歯車のエッジ数(もしくは歯数)を、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)として用いることができる。また、ブレーキECU10から歯車情報を取得した周期の中からフレームの受信タイミングの直前および直後の周期に取得した歯車情報が示す歯車のエッジ数(もしくは歯数)を用いて、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)を演算しても良い。例えば、フレームの受信タイミングの直前および直後の周期に取得した歯車情報が示す歯車のエッジ数(もしくは歯数)の中間値を、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)として用いることができる。 At this time, the reception timing of the frame transmitted from each transmitter 2 does not always coincide with the cycle of acquiring gear information from the brake ECU 10. For this reason, the number of edges (or the number of teeth) of the gear indicated by the gear information acquired in the cycle closest to the reception timing of the frame among the cycles in which the gear information is acquired from the brake ECU 10, that is, the cycle immediately before or immediately after that, Can be used as the number of gear edges (or the number of teeth). Further, when the frame reception timing is obtained by using the number of gear edges (or the number of teeth) indicated by the gear information acquired in the period immediately before and after the frame reception timing from the period in which the gear information is acquired from the brake ECU 10. The number of edges (or the number of teeth) of the gear may be calculated. For example, the intermediate value of the number of gear edges (or the number of teeth) indicated by the gear information acquired immediately before and after the frame reception timing is used as the number of gear edges (or the number of teeth) at the frame reception timing. Can be used.
 そして、このようなフレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)を取得する動作がフレームを受信する毎に繰り返され、取得したフレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)に基づいて車輪位置検出を行う。具体的には、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)のバラツキが前回の受信タイミングのときの歯車のエッジ数(もしくは歯数)に基づいて設定される所定範囲内であるか否かを判定することにより、車輪位置検出を行う。 The operation of obtaining the number of gear edges (or the number of teeth) at the reception timing of the frame is repeated every time the frame is received, and the number of gear edges (or the number of gear edges at the received frame reception timing) The wheel position is detected based on the number of teeth. Specifically, the variation in the number of gear edges (or the number of teeth) at the frame reception timing is within a predetermined range set based on the number of gear edges (or the number of teeth) at the previous reception timing. The wheel position is detected by determining whether or not there is.
 フレームを受信した車輪については、加速度センサ22の角度が所定角度になるタイミングでフレーム送信を行っていることから、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)で示される歯位置が前回のときとほぼ一致する。このため、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)のバラツキが小さく、所定範囲内に収まることになる。このことは、複数回フレームを受信した場合でも成り立ち、各フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)のバラツキは、1回目のフレーム受信タイミングのときに決められる所定範囲内に収まる。一方、フレームを受信した車輪とは異なる車輪については、他の車輪の送信機2から送信されたフレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)で示される歯位置がばらつく。 For the wheel that has received the frame, since the frame is transmitted at the timing at which the angle of the acceleration sensor 22 reaches a predetermined angle, the tooth position indicated by the number of gear edges (or the number of teeth) at the frame reception timing Is almost the same as the previous time. For this reason, the variation in the number of edges (or the number of teeth) of the gears at the frame reception timing is small and falls within a predetermined range. This is true even when multiple frames are received, and the variation in the number of gear edges (or the number of teeth) at the reception timing of each frame is within a predetermined range determined at the first frame reception timing. It will fit. On the other hand, for a wheel different from the wheel that received the frame, the tooth position indicated by the number of edges (or the number of teeth) of the gear at the reception timing of the frame transmitted from the transmitter 2 of the other wheel varies.
 すなわち、車輪速度センサ11a~11dの歯車の回転は各車輪5a~5dと連動しているため、フレームを受信した車輪については、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)で示される歯位置がほぼ一致する。しかし、道路状況や旋回もしくは車線変更などによって各車輪5a~5dの回転状態が変動したりするため、車輪5a~5dの回転状態が完全に同じになることはあり得ない。このため、フレームを受信した車輪とは異なる車輪については、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)で示される歯位置がばらつくのである。 That is, since the rotation of the gears of the wheel speed sensors 11a to 11d is linked to the wheels 5a to 5d, the number of edges (or the number of teeth) of the gear at the reception timing of the frame for the wheel that has received the frame. The tooth positions shown are nearly identical. However, the rotation state of the wheels 5a to 5d varies depending on road conditions, turning or lane change, and the rotation states of the wheels 5a to 5d cannot be completely the same. For this reason, for a wheel that is different from the wheel that received the frame, the tooth position indicated by the number of gear edges (or the number of teeth) at the frame reception timing varies.
 したがって、図4に示したように、イグニッションスイッチ(IG)がオンした当初に歯車12a~12dのエッジ数が0であった状態から、走行開始後に徐々にフレームを受信した車輪とは異なる車輪については、フレームの受信タイミングのときの歯車のエッジ数(もしくは歯数)で示される歯位置にバラツキが生じる。このバラツキが所定範囲内であるか否かを判定することにより、車輪位置検出を行う。 Therefore, as shown in FIG. 4, a wheel that is different from the wheel that gradually received the frame after the start of traveling from the state in which the number of edges of the gears 12a to 12d was 0 when the ignition switch (IG) was turned on. The tooth position indicated by the number of gear edges (or the number of teeth) at the frame reception timing varies. The wheel position is detected by determining whether or not the variation is within a predetermined range.
 例えば、図5Aに示すように、1回目のフレーム送信時の送信機2の位置が1回目受信角度であったとする。また、歯車のエッジ数(もしくは歯数)のバラツキとして許容できる幅であるバラツキ許容幅が1回目受信角度を中心とした180°の範囲(1回目受信角度±90°の範囲)相当の値であるとする。エッジ数であれば1回目受信時のエッジ数を中心とした±24のエッジ数範囲、歯数であれば1回目受信時の歯数を中心とした±12の歯数範囲であるとする。この場合において、図5Bに示すように、2回目のフレーム受信時の歯車のエッジ数(もしくは歯数)が1回目のフレーム受信によって決められたバラツキ許容幅の範囲内であれば、そのエッジ数(もしくは歯数)の車輪はフレーム送信が行われた車輪と一致している可能性があり、TRUE(正しい)となる。 For example, as shown in FIG. 5A, it is assumed that the position of the transmitter 2 at the first frame transmission is the first reception angle. Also, the variation allowable width, which is the allowable width for the number of gear edges (or the number of teeth), is a value corresponding to a range of 180 ° centered on the first reception angle (the range of the first reception angle ± 90 °). Suppose there is. Assume that the number of edges is a range of ± 24 edges centered on the number of edges at the first reception, and the number of teeth is a range of ± 12 teeth centered on the number of teeth at the first reception. In this case, as shown in FIG. 5B, if the number of gear edges (or the number of teeth) at the time of the second frame reception is within the range of allowable variation determined by the first frame reception, the number of edges. The wheel (or the number of teeth) may coincide with the wheel on which the frame was transmitted, and is TRUE (correct).
 ただし、この場合にも2回目のフレーム受信時の送信機2の角度である2回目受信角度を中心としてバラツキ許容幅が決まり、2回目受信角度を中心とした180°(±90°)相当の値となる。このため、前回のバラツキ許容幅となる1回目受信角度を中心とした180°(±90°)のバラツキ許容幅と、2回目受信角度を中心とした180°(±90°)のバラツキ許容幅の重なる部分が新たなバラツキ許容幅(エッジ数範囲が12~48)となり、その重複範囲に新たなバラツキ許容幅を狭めることができる。 However, also in this case, the variation allowable width is determined around the second reception angle that is the angle of the transmitter 2 at the time of the second frame reception, and is equivalent to 180 ° (± 90 °) around the second reception angle. Value. For this reason, a variation allowable width of 180 ° (± 90 °) centered on the first reception angle that is the previous allowable variation width and a variation allowable width of 180 ° (± 90 °) centered on the second reception angle The overlapping portion becomes a new variation allowable width (edge number range is 12 to 48), and the new variation allowable width can be narrowed to the overlapping range.
 したがって、図5Cに示すように、3回目のフレーム受信時の歯車のエッジ数(もしくは歯数)が1、2回目のフレーム受信によって決められたバラツキ許容幅の範囲外であれば、そのエッジ数(もしくは歯数)の車輪はフレーム送信が行われた車輪と一致していないため、FALSE(誤り)となる。このとき、たとえ1回目のフレーム受信によって決められたバラツキ許容幅の範囲内であっても、1、2回目のフレーム受信によって決められたバラツキ許容幅の範囲外であれば、FALSEと判定している。このようにして、受信したフレームを送信した送信機2が車輪5a~5dのいずれに取り付けられたものであるかを特定することが可能となる。 Therefore, as shown in FIG. 5C, if the number of gear edges (or the number of teeth) at the time of the third frame reception is outside the range of allowable variation determined by the first and second frame reception, the number of edges Since the wheel (or the number of teeth) does not coincide with the wheel on which the frame transmission has been performed, FALSE (error) occurs. At this time, even if it is within the range of allowable variation determined by the first frame reception, if it is outside the range of allowable variation determined by the first and second frame reception, it is determined as FALSE. Yes. In this way, it is possible to specify which of the wheels 5a to 5d the transmitter 2 that has transmitted the received frame is attached to.
 すなわち、図6Aに示すように、ID情報としてID1が含まれたフレームについては、そのフレームの受信タイミングの毎に歯車のエッジ数(もしくは歯数)を取得し、それを対応する車輪(左前輪FL、右前輪FR、左後輪RL、右後輪RR)毎に記憶する。そして、フレームを受信するたびに、取得した歯車のエッジ数(もしくは歯数)がバラツキ許容幅の範囲内であるか否かを判定し、その範囲から外れた車輪をフレームが送信された送信機2の取り付けられた車輪候補から除外していく。そして、最後まで除外されなかった車輪をフレームが送信された送信機2の取り付けられた車輪として登録する。ID1が含まれたフレームの場合、右前輪FR、右後輪RR、左後輪RLの順に候補から除外され、最終的に残った左前輪FLをフレームが送信された送信機2の取り付けられた車輪としてID情報と対応付けて登録する。 That is, as shown in FIG. 6A, for a frame including ID1 as ID information, the number of gear edges (or the number of teeth) is acquired at each reception timing of the frame, and the corresponding wheel (left front wheel) is obtained. FL, right front wheel FR, left rear wheel RL, right rear wheel RR). Each time a frame is received, it is determined whether or not the acquired number of gear edges (or the number of teeth) is within the range of allowable variation, and a transmitter that transmits the frame out of the range is transmitted. 2 is excluded from the attached wheel candidates. And the wheel which was not excluded until the last is registered as a wheel with which the transmitter 2 with which the flame | frame was transmitted was attached. In the case of a frame including ID1, the right front wheel FR, the right rear wheel RR, and the left rear wheel RL are excluded from the candidates in this order, and the remaining left front wheel FL is finally attached to the transmitter 2 to which the frame is transmitted. The wheel is registered in association with the ID information.
 そして、図6B~Dに示すように、ID情報としてID2~ID4が含まれたフレームについてもID1が含まれたフレームと同様の処理を行う。これにより、各フレームが送信された送信機2の取り付けられた車輪を特定することができ、送信機2が取り付けられた4輪すべてを特定することが可能となる。 Then, as shown in FIGS. 6B to 6D, the same processing as that for a frame including ID1 is performed for a frame including ID2 to ID4 as ID information. Thereby, it is possible to specify the wheel to which the transmitter 2 to which each frame is transmitted is attached, and to specify all four wheels to which the transmitter 2 is attached.
 このようにして、各フレームが車輪5a~5dのいずれに取り付けられたものであるかを特定する。そして、マイクロコンピュータ33は、フレームを送信してきた各送信機2のID情報を、それが取り付けられた車輪の位置と関連付けて記憶する。 In this way, it is specified which of the wheels 5a to 5d each frame is attached to. Then, the microcomputer 33 stores the ID information of each transmitter 2 that has transmitted the frame in association with the position of the wheel to which it is attached.
 なお、TPMS-ECU3では、車速が所定速度になったときに送信されたフレームを受信することで、その受信タイミングにおける歯車情報を記憶するようにしているが、所定の走行停止判定時速(例えば5km/h)以下になったときに、それまでの歯車情報を破棄している。そして、再び走行開始したときに、新たに上記のようにして車輪位置検出を行うようにしている。 The TPMS-ECU 3 receives the frame transmitted when the vehicle speed reaches the predetermined speed, and stores the gear information at the reception timing. However, the TPMS-ECU 3 stores a predetermined traveling stop determination speed (for example, 5 km). / H) When it becomes below, the gear information so far is discarded. When the vehicle starts running again, the wheel position is newly detected as described above.
 以上のような手法によって、基本的な車輪位置検出を行っている。これにより、走行車輪である左前輪FL、右前輪FR、左後輪RL、右後輪RRの車輪位置検出を行うことが可能となる。なお、車輪位置検出の際に、他車両の送信機から送信されたフレームが受信された場合には、そのフレームに格納されたID情報も候補IDとなり得る。しかしながら、上記した車輪位置特定ロジックを用いた車輪位置の特定中に、他車両の送信機から送信されたフレームが受信されるタイミングが自車両のいずれの車輪の歯車の歯位置とも一致しなくなる。このため、他車両の送信機のID情報が登録されることを避けて、自車両の送信機2のID情報のみが登録されるようにすることができる。 The basic wheel position detection is performed by the above method. As a result, it is possible to detect the wheel positions of the left front wheel FL, the right front wheel FR, the left rear wheel RL, and the right rear wheel RR, which are traveling wheels. In addition, when the frame transmitted from the transmitter of the other vehicle is received when the wheel position is detected, the ID information stored in the frame can be a candidate ID. However, during the specification of the wheel position using the wheel position specifying logic described above, the timing at which the frame transmitted from the transmitter of the other vehicle is received does not match the tooth position of the gear of any wheel of the own vehicle. For this reason, it can avoid registering the ID information of the transmitter of another vehicle, and can register only the ID information of the transmitter 2 of the own vehicle.
 この場合、例えば、特許文献1に示す登録手法を採用すれば、より他車両の送信機のID情報が登録されることを防止することができる。すなわち、上記の車輪位置検出において、自車両の既存のID情報が全く登録されていない場合の車輪位置検出中に他車両の車輪に取り付けられた送信機からのID情報を含むフレームを受信した場合には、その送信機のID情報も候補IDとなり得る。同様に、自車両の既存のID情報が登録されている場合であっても、自車両の車輪5a~5dに取り付けられた送信機2が取り替えられ、受信できているフレームのID情報の数が登録されているID情報の数よりも少ない場合もある。このような場合において、車輪位置検出中に他車両の車輪に取り付けられた送信機からのID情報を含むフレームを受信した場合に、その送信機のID情報も候補IDとなり得る。 In this case, for example, if the registration method shown in Patent Document 1 is adopted, it is possible to prevent registration of ID information of a transmitter of another vehicle. That is, in the above wheel position detection, when a frame including ID information from a transmitter attached to a wheel of another vehicle is received during wheel position detection when no existing ID information of the host vehicle is registered. The ID information of the transmitter can also be a candidate ID. Similarly, even if the existing ID information of the host vehicle is registered, the transmitter 2 attached to the wheels 5a to 5d of the host vehicle is replaced, and the number of ID information of frames that can be received is In some cases, the number is less than the number of registered ID information. In such a case, when a frame including ID information from a transmitter attached to a wheel of another vehicle is received during wheel position detection, the ID information of the transmitter can also be a candidate ID.
 これらの場合には、車輪が特定された後、所定回数(例えば10回)連続してフレームの受信タイミングのときの歯位置がバラツキ許容幅の範囲内に含まれている場合にのみ、ID情報を登録するようにしている。 In these cases, only after the wheel is specified, the ID information is only included when the tooth position at the frame reception timing is included in the variation allowable range continuously for a predetermined number of times (for example, 10 times). Is registered.
 他車両の車輪に取り付けられた送信機のフレームを受信している場合、当該フレームについても、自車両の場合と同様に、そのフレームの受信タイミングの毎に取得された歯車のエッジ数(もしくは歯数)がバラツキ許容幅の範囲内であるか否かが判定される。そして、自車両の送信機2と同様に、他車両の送信機から送信されたフレームについても、バラツキ許容幅の範囲から外れた車輪をフレームが送信された送信機2の取り付けられた車輪候補から除外していくことになる。このとき、消去法が用いられているため、各フレームそれぞれで除外されずに最終的に1つの車輪のみが残った時点で、その車輪がそのフレームを送信した送信機2の取り付けられた車輪候補となる。この時点でそのID情報を登録してしまうと、他車両の車輪に取り付けられた送信機のID情報なのに、誤って自車両のものと登録されることになる。特に、他車両の車輪に取り付けられた送信機から送信されるフレームは、自車両のものではないためバラツキが生じ易く、自車両の車輪5a~5dに取り付けられた送信機2から送信されるフレームよりも早く車輪候補から除外されがちである。このため、他車両の車輪の送信機から送信されたフレームについては、殆どが、早い段階でバラツキ許容幅から外れ、偶然外れなかった車輪がフレームを送信した送信機の取り付けられた車輪候補として特定された状態になり易い。 When a frame of a transmitter attached to a wheel of another vehicle is received, the number of gear edges (or teeth) acquired at each frame reception timing is also received for that frame, as in the case of the host vehicle. It is determined whether or not (number) is within the range of variation tolerance. And, similarly to the transmitter 2 of the own vehicle, for the frame transmitted from the transmitter of the other vehicle, the wheel that is out of the range of the allowable variation range is selected from the wheel candidates attached to the transmitter 2 to which the frame is transmitted. Will be excluded. At this time, since the elimination method is used, at the time when only one wheel is finally left without being excluded in each frame, the wheel candidate to which the transmitter 2 to which the wheel transmits the frame is attached. It becomes. If the ID information is registered at this time, the ID information of the transmitter attached to the wheels of the other vehicle is erroneously registered as that of the own vehicle. In particular, since the frame transmitted from the transmitter attached to the wheel of the other vehicle is not from the own vehicle, the frame is likely to vary, and the frame transmitted from the transmitter 2 attached to the wheels 5a to 5d of the own vehicle. It is apt to be excluded from the wheel candidates earlier. For this reason, most of the frames transmitted from the transmitters of the wheels of other vehicles are identified as wheel candidates that are attached to the transmitters that transmitted the frames. It is easy to become the state that was done.
 しかし、車輪が特定された後、所定回数連続してフレームの受信タイミングのときの歯位置がバラツキ許容幅の範囲内に含まれていることをID情報の登録条件とすれば、その間に他車両の送信機からのフレームの受信タイミングの歯位置はバラツキ許容幅から外れる。したがって、他車両の車輪に取り付けられた送信機のID情報なのに、誤って自車両のものと登録されることを防止することが可能となる。 However, if the ID information registration condition is that the tooth position at the reception timing of the frame is continuously included within the tolerance range after the wheel is specified, the other vehicle is in the meantime. The tooth position of the reception timing of the frame from the transmitter is out of the tolerance range. Therefore, it is possible to prevent the ID information of the transmitter attached to the wheels of the other vehicle from being erroneously registered as that of the own vehicle.
 なお、ここでは車輪が特定された後から所定回数連続してフレームの受信タイミングのときの歯位置がバラツキ許容幅の範囲内に含まれているか否かを判定する場合を想定しているが、勿論、車輪位置検出の開始から所定回数連続しているかの判定としても良い。 In this case, it is assumed that it is determined whether or not the tooth position at the reception timing of the frame is continuously included a predetermined number of times after the wheel is specified, within the range of allowable variation width. Of course, it may be determined whether a predetermined number of times from the start of wheel position detection.
 このように、上記の手法によって、走行車輪である左前輪FL、右前輪FR、左後輪RL、右後輪RRの車輪位置検出を行うことが可能である。ただし、車輪位置検出の際に、候補IDの数が膨大になると、自車両の車輪のID情報を候補IDとして登録できなく可能性がある。したがって、自車両の送信機2や他車両の送信機からのフレームを受信したときに、TPMS-ECU3は、以下に示す候補ID登録処理を実行することで、候補IDの数が膨大になることを抑制している。 As described above, it is possible to detect the wheel positions of the left front wheel FL, the right front wheel FR, the left rear wheel RL, and the right rear wheel RR, which are traveling wheels, by the above method. However, if the number of candidate IDs becomes enormous during wheel position detection, the ID information of the wheels of the host vehicle may not be registered as candidate IDs. Therefore, when a frame is received from the transmitter 2 of the own vehicle or the transmitter of the other vehicle, the TPMS-ECU 3 executes the candidate ID registration process shown below, thereby increasing the number of candidate IDs. Is suppressed.
 図7に示す候補ID登録処理のフローチャートおよび図8に示すデータ更新処理のフローチャートを参照して、TPMS-ECU3が実行する候補ID登録処理の詳細について説明する。なお、図7に示す処理は、上記した走行車輪の車輪位置検出の処理が開始されると、車輪位置検出の対象となる候補IDの選別の為に行われる。そして、ここで選別された候補IDについてのみ、図8に示すデータ更新処理が実行されて、上記した車輪位置確定ロジックによる車輪位置検出の対象とされる。例えば、IGオンによってTPMS-ECU3に電源が投入されているときに、図示しない車輪位置検出の実行スイッチが操作されると、TPMS-ECU3がID登録モードとなる。TPMS-ECU3は、ID登録モードとなったときに、上記した車輪位置検出の処理と共に図7や図8に示す処理を所定の制御周期毎に実行する。 Details of the candidate ID registration process executed by the TPMS-ECU 3 will be described with reference to the flowchart of the candidate ID registration process shown in FIG. 7 and the flowchart of the data update process shown in FIG. Note that the processing shown in FIG. 7 is performed for selecting candidate IDs to be subjected to wheel position detection when the above-described processing for detecting the wheel position of the traveling wheel is started. Then, only the candidate ID selected here is subjected to the data update process shown in FIG. 8 and is subjected to wheel position detection by the wheel position determination logic described above. For example, when a power switch is turned on to turn on the TPMS-ECU 3 when the wheel position detection execution switch (not shown) is operated, the TPMS-ECU 3 enters the ID registration mode. When the TPMS-ECU 3 enters the ID registration mode, the TPMS-ECU 3 executes the processes shown in FIGS. 7 and 8 together with the above-described wheel position detection process at every predetermined control cycle.
 まず、ステップ100において、RF受信、つまりRF帯の電波として送信されたフレームを受信すると、ステップ110以降の処理を実行する。 First, in step 100, when an RF reception, that is, a frame transmitted as an RF band radio wave is received, the processing from step 110 is executed.
 ステップ110では、車両状態が走行中であり、かつ、受信したフレームにG-ONデータが格納されているか否かを判定する。すなわち、ここでは自車両が走行中であり、送信機2に備えられた加速度センサ22がオン状態になっている状態であるか否かを判定している。 In step 110, it is determined whether or not the vehicle state is traveling and G-ON data is stored in the received frame. That is, it is determined here whether or not the host vehicle is traveling and the acceleration sensor 22 provided in the transmitter 2 is in an on state.
 車両状態が走行中であるか否かは、例えばブレーキECU10で車輪速度センサ11a~11dの検出信号に基づいて車速演算を行っていることから、ブレーキECU10から車速データを入手することによって判定することができる。その場合、一般的には車速が発生していれば車両状態が走行中であるとされるが、本ステップでは加速度センサ22がオンの状態になる所定車速を基準として、この所定車速以上となる第1速度以上の車速が発生している場合を車両状態が走行中であるとしている。加速度センサ22がオンの状態になる車速は、加速度センサ22のバラツキによって異なるが、例えば40km/h以上であれば、確実に加速度センサ22がオンの状態になることから、ここでは車速が40km/h以上のときを車両状態が走行中であるとしている。 Whether the vehicle state is traveling or not is determined by obtaining vehicle speed data from the brake ECU 10 because the vehicle ECU calculates the vehicle speed based on detection signals from the wheel speed sensors 11a to 11d, for example. Can do. In this case, generally, if the vehicle speed is generated, the vehicle state is assumed to be running, but in this step, the vehicle speed becomes equal to or higher than the predetermined vehicle speed on the basis of the predetermined vehicle speed at which the acceleration sensor 22 is turned on. The vehicle state is assumed to be traveling when the vehicle speed equal to or higher than the first speed is generated. The vehicle speed at which the acceleration sensor 22 is turned on varies depending on variations in the acceleration sensor 22, but for example, if it is 40 km / h or more, the acceleration sensor 22 is surely turned on, so the vehicle speed here is 40 km / h. It is assumed that the vehicle state is running when h or more.
 走行車輪の場合、自車両が走行中の際には、走行車輪の車輪速度が所定速度に至っていれば、その走行車輪に取り付けられた送信機2のフレームにはG-ONデータが格納されることになる。このため、車両状態が走行中の際に、受信したフレームにG-ONデータが格納されている場合には、自車両の車輪5a~5dの送信機2から送信されたフレームの可能性がある。したがって、ステップ110において、車両状態が走行中であり、かつ、受信したフレームにG-ONデータが格納されていることを候補IDの登録条件として設定している。 In the case of a traveling wheel, when the vehicle is traveling, if the wheel speed of the traveling wheel reaches a predetermined speed, G-ON data is stored in the frame of the transmitter 2 attached to the traveling wheel. It will be. For this reason, when G-ON data is stored in the received frame when the vehicle state is traveling, there is a possibility that the frame is transmitted from the transmitter 2 of the wheels 5a to 5d of the host vehicle. . Accordingly, in step 110, the candidate ID registration condition is set such that the vehicle state is traveling and that the G-ON data is stored in the received frame.
 ただし、この候補IDの登録条件次第では、他車両のものばかり候補IDに登録されてTPMS-ECU3のメモリ容量一杯になる等、自車両の車輪の各送信機のID情報が候補IDとして登録されなくなる可能性がある。 However, depending on the registration conditions of this candidate ID, the ID information of each transmitter of the wheel of the host vehicle is registered as the candidate ID, such that only the other vehicle is registered as the candidate ID and the memory capacity of the TPMS-ECU 3 is full. There is a possibility of disappearing.
 したがって、図7に示す候補ID登録処理においては、ステップ110の判定で候補IDの登録条件の1つとしている車両状態が走行中であることの判定条件を車速が第1速度以上発生していることとしている。このような条件を設定することで、候補IDとして選別されるID情報の数を絞り、TPMS-ECU3のメモリ容量が一杯になることを抑制することができる。 Therefore, in the candidate ID registration process shown in FIG. 7, the vehicle speed is higher than or equal to the first speed as a determination condition that the vehicle state, which is one of the candidate ID registration conditions in the determination of step 110, is running. I am going to do that. By setting such conditions, it is possible to reduce the number of ID information selected as candidate IDs and suppress the memory capacity of the TPMS-ECU 3 from becoming full.
 そして、ステップ110で肯定判定されるとステップ120に進み、受信したフレームに格納されたID情報を候補IDとしてTPMS-ECU3のメモリに登録(格納)し、図8に示すデータ更新処理に移行する。つまり、候補IDの登録条件を厳しくすることで登録される候補IDの数を絞りつつ、一旦、候補IDとして登録したID情報については、この後は図8に示すデータ更新処理を実行することでデータ更新がされ易くなるようにする。 If an affirmative determination is made in step 110, the process proceeds to step 120, where the ID information stored in the received frame is registered (stored) in the memory of the TPMS-ECU 3 as a candidate ID, and the process proceeds to the data update process shown in FIG. . That is, by narrowing down the candidate ID registration conditions and narrowing down the number of candidate IDs to be registered, the data update process shown in FIG. Make it easier to update data.
 図8に示すデータ更新処理についても、図7に示す候補ID登録処理と同様、まず、ステップ200において、RF受信、つまりRF帯の電波として送信されたフレームを受信すると、ステップ210以降の処理を実行する。 In the data update process shown in FIG. 8, as in the candidate ID registration process shown in FIG. 7, first, in step 200, when a frame transmitted as an RF reception, that is, an RF band radio wave is received, the processes in and after step 210 are performed. Execute.
 ステップ210では、車両状態が走行中であり、かつ、受信したフレームがG-ONデータを格納した候補IDのもの、つまり図7に示す候補ID登録処理において既に登録されているID情報であるか否かを判定する。このとき、候補IDのものであることを条件とすることで、候補IDとして登録されているID情報についてはステップ220以降の処理に進めないようにしている。 In step 210, whether the vehicle state is running and the received frame is of a candidate ID storing G-ON data, that is, whether it is ID information already registered in the candidate ID registration process shown in FIG. Determine whether or not. At this time, on condition that it is a candidate ID, the ID information registered as the candidate ID is not allowed to proceed to the processing after step 220.
 また、このとき、候補IDであることを前提としていることから、車両状態が走行中であるとの判定基準をステップ110よりも緩めている。具体的には、本ステップでは加速度センサ22がオンの状態になる所定車速を基準として、この所定車速未満であり、かつ、精度良く車速演算が行える第2速度以上の車速が発生している場合を車両状態が走行中であるとしている。加速度センサ22がオンの状態になっていない車速は、加速度センサ22のバラツキによって異なるが、例えば5km/hであれば、加速度センサ22がオンの状態になっていない。また、精度良く演算できる車速についても、車輪速度センサ11a~11dの精度などによって異なるが、例えば5km/h以上の車速であれば精度良く演算できる。したがって、ここでは車速が5km/h以上のときを車両状態が走行中であると判定している。 Also, at this time, since it is premised on the candidate ID, the determination criterion that the vehicle state is running is loosened from step 110. Specifically, in this step, when a vehicle speed that is lower than the predetermined vehicle speed and that can accurately calculate the vehicle speed is generated with reference to the predetermined vehicle speed at which the acceleration sensor 22 is turned on. The vehicle state is running. The vehicle speed at which the acceleration sensor 22 is not turned on varies depending on variations in the acceleration sensor 22, but for example, if it is 5 km / h, the acceleration sensor 22 is not turned on. Also, the vehicle speed that can be calculated with high accuracy varies depending on the accuracy of the wheel speed sensors 11a to 11d, but can be calculated with high accuracy if the vehicle speed is 5 km / h or more, for example. Therefore, here, it is determined that the vehicle state is traveling when the vehicle speed is 5 km / h or more.
 なお、G-ONデータは、一度、加速度センサ22がオン状態になったことが確認されたときに、停車するまで、もしくは、停車してから所定時間が経過するまでは継続的にフレーム中に含まれる。つまり、車速が所定速度に至って加速度センサ22がオンの状態になるまではG-ONデータがフレームに格納されないが、一旦、加速度センサ22がオン状態になると、車速が低下してもG-ONデータがフレーム中に格納されたままとなる。したがって、上記ステップ210のように、車速が第1速度よりも低い第2速度近辺であったとしても、G-ONデータを確認することが可能である。 Note that the G-ON data is continuously recorded in the frame until it is confirmed that the acceleration sensor 22 is turned on once or until a predetermined time elapses after the vehicle stops. included. That is, the G-ON data is not stored in the frame until the vehicle speed reaches a predetermined speed and the acceleration sensor 22 is turned on. Once the acceleration sensor 22 is turned on, the G-ON data is not detected even if the vehicle speed decreases. Data remains stored in the frame. Therefore, even if the vehicle speed is near the second speed, which is lower than the first speed, as in step 210, the G-ON data can be confirmed.
 そして、ステップ210で肯定判定されると、ステップ220に進み、受信したフレームに格納されたID情報、つまり候補IDの1つについてのデータ更新を行う。具体的には、当該候補IDについて、フレームの受信タイミングでの歯車情報を取得し、それが示す歯車のエッジ数(もしくは歯数)がバラツキ許容幅に含まれるか否かの判定を行うなど、上記輪位置特定ロジックに従った車輪位置検出のためのデータ更新を行う。これに基づき、図6Aから図6Dに示したように、フレーム受信する毎に候補IDについてはデータ更新が為され、車輪位置検出が行われることになる。 If the determination in step 210 is affirmative, the process proceeds to step 220, where data update is performed for one of the ID information stored in the received frame, that is, one of the candidate IDs. Specifically, for the candidate ID, gear information at the reception timing of the frame is acquired, and it is determined whether or not the number of gear edges (or the number of teeth) indicated by the gear ID is included in the variation allowable width. Data update for wheel position detection according to the wheel position specifying logic is performed. Based on this, as shown in FIGS. 6A to 6D, each time a frame is received, the candidate ID is updated, and the wheel position is detected.
 このようにして車輪位置検出が行われると、その後は、タイヤ空気圧検出が行われる。具体的には、タイヤ空気圧検出の際には、一定周期毎に各送信機2からフレームが送信され、各送信機2からフレームが送信されるたびに、走行車輪4輪分のフレームがTPMS-ECU3で受信される。そして、TPMS-ECU3では、各フレームに格納されたID情報に基づいて車輪5a~5dに取り付けられたいずれの送信機2から送られてきたフレームであるかを特定し、タイヤ空気圧に関する情報より各車輪5a~5dのタイヤ空気圧を検出する。これにより、各車輪5a~5dのタイヤ空気圧の低下を検出でき、車輪5a~5dのいずれのタイヤ空気圧が低下しているかを特定することが可能となる。そして、タイヤ空気圧の低下が検出されると、その旨をメータ4に伝えることで、メータ4によって車輪5a~5dを特定しつつタイヤ空気圧の低下を示す表示を行い、ドライバに特定車輪のタイヤ空気圧の低下を報知する。 If the wheel position is detected in this way, then the tire air pressure is detected. Specifically, when detecting tire air pressure, frames are transmitted from each transmitter 2 at regular intervals, and every time a frame is transmitted from each transmitter 2, frames for four traveling wheels are converted into TPMS- Received by the ECU 3. Then, the TPMS-ECU 3 identifies which frame is sent from the transmitter 2 attached to the wheels 5a to 5d based on the ID information stored in each frame, and determines each frame from information related to tire pressure. The tire pressure of the wheels 5a to 5d is detected. As a result, a decrease in tire air pressure of each of the wheels 5a to 5d can be detected, and it is possible to identify which tire air pressure of the wheels 5a to 5d is decreasing. When a decrease in tire air pressure is detected, the fact is notified to the meter 4 so that the meter 4 displays a display indicating the decrease in tire air pressure while identifying the wheels 5a to 5d, and the tire air pressure of the specific wheel is indicated to the driver. Announcing a drop in
 以上説明したように、車輪5a~5dと連動して回転させられる歯車12a~12dの歯の通過を検出する車輪速度センサ11a~11dの検出信号に基づいて、歯車12a~12dの歯位置を示す歯車情報を所定周期毎に取得している。そして、フレームの受信タイミングのときの歯位置に基づいてバラツキ許容幅を設定し、該バラツキ許容幅を設定した後におけるフレームの受信タイミングのときの歯位置がバラツキ許容幅の範囲外であれば、該フレームが送信された送信機2の取り付けられた車輪の候補から除外していき、残った車輪をフレームが送信された送信機2の取り付けられた車輪として登録している。このため、多くのデータ量が揃わなくても走行車輪の車輪位置の特定を行うことができる。 As described above, the tooth positions of the gears 12a to 12d are shown based on the detection signals of the wheel speed sensors 11a to 11d that detect the passage of the teeth of the gears 12a to 12d rotated in conjunction with the wheels 5a to 5d. Gear information is acquired every predetermined period. And if the variation allowable width is set based on the tooth position at the reception timing of the frame and the tooth position at the reception timing of the frame after setting the variation allowable width is outside the range of the variation allowable width, The wheel is excluded from the wheel candidates attached to the transmitter 2 to which the frame is transmitted, and the remaining wheels are registered as wheels to which the transmitter 2 to which the frame is transmitted is attached. For this reason, the wheel position of the traveling wheel can be specified without a large amount of data.
 そして、候補IDを登録する際に、登録条件を厳しくすることで登録されるID情報の数を絞りつつ、一旦、候補IDとして登録されたID情報については、データ更新がされ易くなるようにしている。具体的には、登録条件として用いている車両状態が走行中であることの判定基準を、加速度センサ22がオンの状態となっている第1速度以上の車速が発生していることとしている。そして、データ更新の条件として用いている車両状態が走行中であることの判定基準を、第1速度よりも低い第2速度以上の車速が発生していることとしている。 When registering candidate IDs, the number of pieces of ID information to be registered is narrowed down by tightening the registration conditions, and the ID information once registered as candidate IDs can be easily updated. Yes. Specifically, a criterion for determining that the vehicle state used as the registration condition is running is that a vehicle speed equal to or higher than the first speed at which the acceleration sensor 22 is on is generated. The criterion for determining that the vehicle state used as the data update condition is running is that a vehicle speed equal to or higher than the second speed that is lower than the first speed is generated.
 このように、登録条件を厳しくすることで、候補IDとして選別されるID情報の数を絞り、TPMS-ECU3のメモリ容量が一杯になることを抑制することができる。したがって、他車両の車輪の送信機のID情報が候補IDとして登録されることを抑制しつつ、自車両の車輪の送信機2のID情報が的確に候補IDとして登録されるようにできる。また、データ更新の条件を登録条件よりも緩くすることで、候補IDについてのデータ更新がされ易くなるようにできる。 As described above, by tightening the registration conditions, it is possible to reduce the number of ID information selected as candidate IDs and suppress the memory capacity of the TPMS-ECU 3 from becoming full. Therefore, it is possible to accurately register the ID information of the transmitter 2 of the wheel of the host vehicle as the candidate ID while suppressing the registration of the ID information of the transmitter of the wheel of the other vehicle as the candidate ID. Further, by making the data update condition looser than the registration condition, it is possible to easily update the data for the candidate ID.
 このため、自車両の車速が第2車速よりも大きくても、加速度センサ22がオンの状態になっていない速度範囲(例えば10km/h)であった場合には、フレーム中にG-ONデータが含まれた他車両の車輪のID情報は候補IDとして登録されない。また、自車両が例えば50km/hで走行中に、フレーム中にG-OFFデータが含まれた他車両の車輪のID情報も候補IDとして登録されない。 For this reason, even if the vehicle speed of the host vehicle is higher than the second vehicle speed, if the acceleration sensor 22 is in a speed range (for example, 10 km / h) in which the acceleration sensor 22 is not turned on, the G-ON data is included in the frame. The ID information of the wheel of the other vehicle in which is included is not registered as a candidate ID. Further, when the host vehicle is traveling at, for example, 50 km / h, the ID information of the wheels of other vehicles whose G-OFF data is included in the frame is not registered as candidate IDs.
 また、自車両の車速が第1速度に一旦達してから、第1速度未満で走行し続けていた場合でも、その後は第2速度以上の車速であればデータ更新が為されるようにでき、より早く車輪位置検出が完了するようにできる。つまり、G-ONデータについては、一旦、加速度センサ22がオンの状態になったことが確認されれば車輪位置検出中にはフレームに含まれたままとなるため、例えば、自車両が走行中であると判定されさえすれば、自車両が低車速で走行していたとしても良い。 In addition, even if the vehicle speed of the host vehicle once reached the first speed and continued to travel below the first speed, the data can be updated if the vehicle speed is equal to or higher than the second speed thereafter. The wheel position detection can be completed earlier. In other words, once it is confirmed that the acceleration sensor 22 is turned on, the G-ON data remains included in the frame during the wheel position detection. As long as it is determined that the vehicle is traveling at a low vehicle speed.
 (他の実施形態)
 実施形態は上記した実施形態に限定されるものではなく、適宜変更が可能である。
(Other embodiments)
The embodiment is not limited to the above-described embodiment, and can be appropriately changed.
 例えば、上記実施形態では、走行車輪側の車輪位置検出として、フレームの受信タイミング毎にバラツキ許容幅を変更し、徐々にバラツキ許容幅が狭くなるようにする形態を例に挙げて説明した。しかしながら、走行車輪側の車輪位置検出の方法については、他の手法、例えばバラツキ許容幅を一定として徐々に狭くしない方法であっても良い。 For example, in the above embodiment, as an example of detecting the wheel position on the traveling wheel side, the variation allowable width is changed at each frame reception timing, and the variation allowable width is gradually narrowed. However, the method of detecting the wheel position on the traveling wheel side may be another method, for example, a method in which the variation allowable width is constant and is not gradually narrowed.
 また、上記実施形態では、フレームの受信タイミング毎にバラツキ許容幅を変更し、徐々にバラツキ許容幅が狭くなるようにしているが、歯位置を中心として設定されるバラツキ許容幅については一定としている。この歯位置を中心として設定されるバラツキ許容幅についても変更可能である。例えば、歯位置のバラツキは、車速が大きいほど大きくなる可能性がある。このため、車速が大きくなるほどバラツキ許容幅を大きくすることで、より的確なバラツキ許容幅を設定できる。また、加速度センサ22で加速度検出を行うときのサンプリング周期が長いほど、加速度センサ22の角度が所定角度になったときのタイミングの検出精度が落ちることから、それに応じてバラツキ許容幅を変更することで、より的確なバラツキ許容幅を設定できる。その場合、送信機2側でサンプリング周期などを把握していることから、送信機2が送信するフレーム内にバラツキ許容幅の大きさを決めるデータを含めて送信するようにすることができる。 Further, in the above embodiment, the variation allowable width is changed at each frame reception timing so that the variation allowable width is gradually narrowed. However, the variation allowable width set around the tooth position is constant. . The variation allowable width set around this tooth position can also be changed. For example, the variation in the tooth position may increase as the vehicle speed increases. For this reason, it is possible to set a more accurate variation allowable width by increasing the variation allowable width as the vehicle speed increases. In addition, the longer the sampling period when the acceleration sensor 22 performs acceleration detection, the lower the timing detection accuracy when the angle of the acceleration sensor 22 becomes a predetermined angle, and therefore the variation tolerance is changed accordingly. Thus, a more accurate variation tolerance can be set. In that case, since the transmitter 2 knows the sampling period and the like, the frame transmitted by the transmitter 2 can be transmitted including data for determining the variation allowable width.
 また、上記実施形態では、フレーム送信を行う角度として、角度が0°の位置を各車輪5a~5dの中心軸を中心として加速度センサ22が上方位置に位置しているときとしている。しかしながら、これは単なる一例であり、車輪の周方向の任意の位置を角度0°とすればよい。 In the above embodiment, the angle at which frame transmission is performed is that the position where the angle is 0 ° is when the acceleration sensor 22 is positioned above the center axis of each wheel 5a to 5d. However, this is merely an example, and an arbitrary position in the circumferential direction of the wheel may be set to 0 °.
 上記実施形態では、TPMS-ECU3がブレーキECU10から歯車情報を取得するようにしている。しかしながら、TPMS-ECU3が歯車情報として歯車の歯のエッジ数もしくは歯数を取得できればよいことから、他のECUから取得しても良いし、車輪速度センサ11a~11dの検出信号を入力し、その検出信号から歯車の歯のエッジ数もしくは歯数を取得するようにしても良い。特に、上記実施形態では、TPMS-ECU3とブレーキECU10を別々のECUで構成する場合について説明したが、これらが一体化された単独のECUで構成される場合もあり得る。その場合には、そのECUが直接車輪速度センサ11a~11dの検出信号を入力し、その検出信号から歯車の歯のエッジ数もしくは歯数を取得することになる。また、その場合には、歯車の歯のエッジ数もしくは歯数を常時取得することができるため、これらの情報を所定周期毎に取得する場合と異なり、フレームの受信タイミング丁度の歯車情報に基づいて車輪位置検出を行うことが可能となる。 In the above embodiment, the TPMS-ECU 3 acquires the gear information from the brake ECU 10. However, since it is sufficient that the TPMS-ECU 3 can acquire the number of teeth or the number of teeth of the gear as the gear information, it may be acquired from another ECU, or the detection signals of the wheel speed sensors 11a to 11d are input, The number of teeth or the number of teeth of the gear may be acquired from the detection signal. In particular, in the above-described embodiment, the case where the TPMS-ECU 3 and the brake ECU 10 are configured as separate ECUs has been described, but there may be a case where they are configured as a single ECU in which these are integrated. In that case, the ECU directly inputs the detection signals of the wheel speed sensors 11a to 11d, and acquires the number of teeth or the number of teeth of the gear from the detection signals. In that case, since the number of teeth or the number of teeth of the gear can always be obtained, unlike the case where these pieces of information are obtained every predetermined period, based on the gear information exactly at the reception timing of the frame. Wheel position detection can be performed.
 また、上記実施形態では、走行車輪となる4つの車輪5a~5dが備えられた車両1に対して備えられた車輪位置検出装置について説明したが、さらに走行車輪の車輪数が多い車両についても、同様に実施形態とすることができる。 In the above embodiment, the wheel position detection device provided for the vehicle 1 provided with the four wheels 5a to 5d serving as the traveling wheels has been described. However, for a vehicle having a larger number of traveling wheels, It can be set as embodiment similarly.
 なお、実施形態では、車輪速度センサ11a~11dにより車輪5a~5dの回転に連動して回転させられる歯車の歯の通過を検出できれば良い。このため、歯車としては、外周面が導体とされた歯の部分と歯の間に位置する部分が交互に繰り返される磁気抵抗の異なる構造であれば良い。つまり、外縁部が凹凸とされることで外周面が導体となる凸部と非導体となる空間で構成された一般的なもののみではなく、例えば外周面が導体となる部分と非導体となる絶縁体で構成されたロータスイッチ等も含まれる(例えばJP-H10-048233A参照)。 In the embodiment, it is sufficient that the wheel speed sensors 11a to 11d can detect the passage of gear teeth that are rotated in conjunction with the rotation of the wheels 5a to 5d. For this reason, as a gear, what is necessary is just the structure from which the magnetic resistance differs in which the part located in between the tooth | gear part by which the outer peripheral surface was made into the conductor, and a tooth | gear is repeated. In other words, the outer edge portion is made uneven so that the outer peripheral surface is not only a general structure composed of a convex portion that becomes a conductor and a space that becomes a nonconductor, but, for example, the outer peripheral surface becomes a conductor and a nonconductor A rotor switch made of an insulator is also included (see, for example, JP-H10-048233A).
 また、車輪位置検出は、基本的には車両が実走行する際に行われるが、4輪駆動車両のように各車輪が回転可能な車両であれば、シャシーダイナモなどの仮想走行が可能な装置を用いる場合にも実施可能であるため、走行中とは実走行する場合に限らない。 The wheel position detection is basically performed when the vehicle actually travels, but if the vehicle can rotate each wheel, such as a four-wheel drive vehicle, a device capable of virtual traveling such as a chassis dynamo. Since it can be implemented also when using, traveling is not limited to actual traveling.
 なお、各図中に示したステップは、各種処理を実行する部(手段)に対応するものである。すなわち、ステップ110の処理を実行する部分が第1判定部(手段)、ステップ120の処理を実行する部分が候補登録部(手段)に相当する。また、ステップ210の処理を実行する部分が第2判定部(手段)、ステップ220の処理を実行する部分がデータ更新部(手段)に相当する。 Note that the steps shown in each figure correspond to units (means) that execute various processes. That is, the part that executes the process of step 110 corresponds to the first determination unit (means), and the part that executes the process of step 120 corresponds to the candidate registration part (means). Further, the part that executes the process of step 210 corresponds to the second determination unit (means), and the part that executes the process of step 220 corresponds to the data update part (means).
 以上、本開示の係る実施形態を例示したが、実施形態は上述の実施形態に限定されるものではない。例えば、異なる実施形態に開示された技術的部位を適宜組み合わせて得られる実施形態についても、本開示の実施形態の範囲に含まれる。

 
As mentioned above, although embodiment which concerns on this indication was illustrated, embodiment is not limited to the above-mentioned embodiment. For example, embodiments obtained by appropriately combining technical parts disclosed in different embodiments are also included in the scope of the embodiments of the present disclosure.

Claims (4)

  1.  車体(6)に対してタイヤを備えた複数の車輪(5a~5d)が取り付けられた車両(1)に適用され、
     前記複数の車輪それぞれに設けられ、固有の識別情報を含めたフレームを作成すると共に送信する第1制御部(23)を有する送信機(2)と、
     前記車体側に設けられ、受信アンテナ(31)を介して前記送信機から送信されたフレームを受信したのち、該フレームに含まれた前記識別情報のうち登録する候補となる候補識別情報を選別すると共に、該候補識別情報の中から、自車両の前記複数の車輪に設けられた前記送信機と対応するものを特定し、前記複数の車輪と該複数の車輪それぞれに設けられた前記送信機の識別情報とを対応づけて記憶する車輪位置検出を行う第2制御部(33)を有する受信機(3)とを備えた車輪位置検出装置であって、
     前記送信機は、該送信機が取り付けられた車輪の回転に伴って変化する重力加速度成分を含む加速度に応じた検出信号を出力する加速度センサ(22)を有すると共に、前記第1制御部の機能として、該送信機の取り付けられた車輪の車輪速度が前記加速度センサによる加速度検出が行えるオンの状態となる所定速度に至ったことを検知して、該検知結果に基づいて前記加速度センサの状態を示すデータを前記フレームに格納する機能を有し、
     前記第1制御部は、該送信機が取り付けられた車輪の中心軸を中心とし、かつ、該車輪の周方向の任意の位置を角度0°として、前記加速度センサの検出信号に含まれる重力加速度成分に基づいて前記送信機の角度を検出すると共に、該角度が所定の送信角度になるタイミングで繰り返し前記フレームを送信させ、
     前記第2制御部は、前記複数の車輪と連動して回転させられると共に導体とされた歯の部分と前記歯の間に位置する部分が交互に繰り返される磁気抵抗の異なる外周面を有する歯車(12a~12d)の歯の通過を検出する車輪速度センサ(11a~11d)の検出信号に基づいて、前記歯車の歯位置を示す歯車情報を取得すると共に、前記フレームの受信タイミングのときの前記歯位置に基づいて、前記フレームが送信された送信機の取り付けられた車輪を特定して登録することで前記車輪位置検出を行っており、
     前記受信機の前記第2制御部には、
     前記車両が前記所定速度以上に設定された第1速度以上で走行中の状態であり、かつ、受信した前記フレームに格納された前記加速度センサの状態を示すデータが該加速度センサがオンの状態であるという第1条件を満たすか否かを判定する第1判定部(S110)と、
     前記第1判定部で前記第1条件を満たしていると判定されると、受信した前記フレームに格納された前記識別情報を前記候補識別情報として登録する候補登録部(S120)と、
     前記候補登録部にて登録された前記候補識別情報が含まれるフレームを受信すると、前記車両が前記所定速度未満に設定された第2速度以上で走行中の状態であり、かつ、受信した前記フレームに格納された前記加速度センサの状態を示すデータが、該加速度センサがオンの状態であることを示しているという第2条件を満たすか否かを判定する第2判定部(S210)と、
     前記第2判定部で前記第2条件を満たしていると判定されると、受信した前記フレームの受信タイミングのときの歯位置のデータを前記車輪位置検出に用いる新たなデータとして更新するデータ更新部(S220)と、が備えられている車輪位置検出装置。
    Applied to a vehicle (1) in which a plurality of wheels (5a to 5d) having tires are attached to a vehicle body (6);
    A transmitter (2) having a first control unit (23) that is provided on each of the plurality of wheels and generates and transmits a frame including unique identification information;
    After receiving the frame transmitted from the transmitter via the receiving antenna (31) provided on the vehicle body side, the candidate identification information to be registered among the identification information included in the frame is selected. In addition, from among the candidate identification information, the one corresponding to the transmitter provided on the plurality of wheels of the host vehicle is specified, and the plurality of wheels and the transmitter provided on each of the plurality of wheels are identified. A wheel position detection device comprising a receiver (3) having a second control unit (33) for detecting wheel position for storing identification information in association with each other,
    The transmitter includes an acceleration sensor (22) that outputs a detection signal corresponding to acceleration including a gravitational acceleration component that changes with rotation of a wheel to which the transmitter is attached, and functions of the first control unit. Detecting that the wheel speed of the wheel to which the transmitter is attached has reached a predetermined speed at which acceleration can be detected by the acceleration sensor, and determining the state of the acceleration sensor based on the detection result. Having the function of storing the indicated data in the frame;
    The first control unit has a gravitational acceleration included in the detection signal of the acceleration sensor with the central axis of the wheel to which the transmitter is attached as the center and an arbitrary position in the circumferential direction of the wheel as an angle of 0 ° The angle of the transmitter is detected based on the component, and the frame is repeatedly transmitted at a timing at which the angle becomes a predetermined transmission angle.
    The second control unit is a gear having outer peripheral surfaces with different magnetic resistances that are rotated in conjunction with the plurality of wheels and have a portion of a tooth that is a conductor and a portion that is positioned between the teeth alternately repeated ( 12a to 12d) acquires gear information indicating tooth positions of the gears based on detection signals of wheel speed sensors (11a to 11d) for detecting passage of teeth, and the teeth at the reception timing of the frame. Based on the position, the wheel position detection is performed by identifying and registering the wheel on which the transmitter to which the frame was transmitted is attached,
    In the second control unit of the receiver,
    The vehicle is in a state where the vehicle is traveling at the first speed or higher set at the predetermined speed or higher, and the data indicating the state of the acceleration sensor stored in the received frame is in a state where the acceleration sensor is on. A first determination unit (S110) that determines whether or not the first condition is satisfied;
    A candidate registration unit (S120) for registering the identification information stored in the received frame as the candidate identification information when the first determination unit determines that the first condition is satisfied;
    When the frame including the candidate identification information registered by the candidate registration unit is received, the vehicle is in a state of traveling at the second speed or higher set below the predetermined speed, and the received frame A second determination unit (S210) for determining whether or not the data indicating the state of the acceleration sensor stored in (2) satisfies a second condition that the acceleration sensor indicates that the acceleration sensor is on;
    When it is determined that the second condition is satisfied by the second determination unit, the data update unit updates the data of the tooth position at the reception timing of the received frame as new data used for the wheel position detection (S220) and a wheel position detecting device.
  2.  前記第2制御部は、前記フレームの受信タイミングのときの前記歯位置に基づいてバラツキ許容幅を設定し、該バラツキ許容幅を設定した後における前記フレームの受信タイミングのときの前記歯位置が前記バラツキ許容幅の範囲外であれば、該フレームが送信された送信機の取り付けられた車輪の候補から除外していき、残った車輪を前記フレームが送信された送信機の取り付けられた車輪として特定して登録することで前記車輪位置検出を行っており、受信した前記フレームの受信タイミングのときの歯位置のデータとして、前記データ更新部にて更新されたデータを用いる請求項1に記載の車輪位置検出装置。 The second control unit sets a variation allowable width based on the tooth position at the reception timing of the frame, and the tooth position at the reception timing of the frame after setting the variation allowable width If it is outside the range of allowable variation, the frame is excluded from the candidate wheels attached to the transmitter to which the frame is transmitted, and the remaining wheels are identified as the wheels to which the transmitter from which the frame is transmitted are attached. The wheel according to claim 1, wherein the wheel position is detected by registering and the data updated by the data update unit is used as tooth position data at the reception timing of the received frame. Position detection device.
  3.  前記加速度センサの状態を示すデータは、前記加速度センサがオンの状態であることを示す加速度オンデータである請求項1または2に記載の車輪位置検出装置。 The wheel position detection device according to claim 1 or 2, wherein the data indicating the state of the acceleration sensor is acceleration on data indicating that the acceleration sensor is in an on state.
  4.  請求項1ないし3のいずれか1つに記載の車輪位置検出装置を含むタイヤ空気圧検出システムであって、
     前記送信機は、前記複数の車輪それぞれに備えられた前記タイヤの空気圧に応じた検出信号を出力するセンシング部(21)を備え、前記第1制御部によって前記センシング部の検出信号を信号処理したタイヤ空気圧に関する情報をフレームに格納したのち、当該フレームを前記受信機に送信し、
     前記受信機は、前記第2制御部にて、該タイヤ空気圧に関する情報より、前記複数の車輪それぞれに備えられた前記タイヤの空気圧を検出するタイヤ空気圧検出システム。

     
    A tire pressure detection system including the wheel position detection device according to any one of claims 1 to 3,
    The transmitter includes a sensing unit (21) that outputs a detection signal corresponding to an 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 storing information about tire pressure in a frame, send the frame to the receiver,
    The receiver is a tire air pressure detection system in which the second control unit detects air pressures of the tires provided in each of the plurality of wheels from information related to the tire air pressure.

PCT/JP2016/000351 2015-01-28 2016-01-25 Wheel position detection device and tire pressure detection system provided with same WO2016121366A1 (en)

Applications Claiming Priority (2)

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JP2015-014544 2015-01-28
JP2015014544A JP2016137841A (en) 2015-01-28 2015-01-28 Wheel position detection device and tire pneumatic pressure detection system with same

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004082853A (en) * 2002-08-26 2004-03-18 Denso Corp Transmitter id registering method and system, transmitter discriminating method and system, and tire pneumatic pressure monitoring device and program
JP2006015955A (en) * 2004-07-05 2006-01-19 Honda Motor Co Ltd Tire air pressure monitoring system and tire air pressure monitoring method
JP2014031144A (en) * 2012-08-06 2014-02-20 Denso Corp Wheel position detection device and tire pressure detection device provided with the same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004082853A (en) * 2002-08-26 2004-03-18 Denso Corp Transmitter id registering method and system, transmitter discriminating method and system, and tire pneumatic pressure monitoring device and program
JP2006015955A (en) * 2004-07-05 2006-01-19 Honda Motor Co Ltd Tire air pressure monitoring system and tire air pressure monitoring method
JP2014031144A (en) * 2012-08-06 2014-02-20 Denso Corp Wheel position detection device and tire pressure detection device provided with the same

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