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JP-7856178-B2 - Wheel monitoring system

JP7856178B2JP 7856178 B2JP7856178 B2JP 7856178B2JP-7856178-B2

Inventors

  • 曹 冷馳

Assignees

  • 株式会社デンソー

Dates

Publication Date
20260511
Application Date
20250205

Claims (6)

  1. A wheel monitoring system applicable to a vehicle (10) in which a plurality of wheels (10a to 10d), including tires, are attached to a vehicle body (11), A tire sensor (2) is provided on the wheel and includes an acceleration sensor (22) that outputs an acceleration that changes with the rotation of the wheel, The vehicle comprises an on-board unit (3) provided on the vehicle body, The tire sensor and the in-vehicle device are configured to communicate bidirectionally. The in-vehicle unit determines whether the vehicle is parked, stopped, or driving based on the vehicle's speed, the state of the vehicle's doors, and the on/off status of the vehicle's ignition switch, and transmits information including the determination result to the tire sensor. A wheel monitoring system comprising a tire sensor that identifies the current state of the vehicle based on the information notified from the in-vehicle device, and determines whether the wheel has been stolen and whether it is possible that the tire has been rotated or replaced, based on the combination of the identified state of the vehicle and the sensor output of the acceleration sensor.
  2. The aforementioned in-vehicle device is When the aforementioned driving speed is below a predetermined value, the vehicle's doors are locked, and the ignition switch is off, it is determined that the vehicle is in the parked state. If the aforementioned driving speed is less than the predetermined value, the ignition switch is on, or the vehicle doors are unlocked, it is determined that the vehicle is in the stationary state. The wheel monitoring system according to claim 1, wherein the system determines that the state of the vehicle is the driving state when the driving speed is equal to or greater than the predetermined value and the ignition switch is turned ON.
  3. The wheel monitoring system according to claim 1 or 2, wherein the tire sensor determines that the wheel has been stolen when a predetermined acceleration change is detected by the acceleration sensor while the vehicle is parked.
  4. The wheel monitoring system according to claim 1 or 2, wherein the tire sensor determines that, when the vehicle is stationary, a predetermined change in acceleration is detected by the acceleration sensor, there is a possibility that the tire has been rotated or replaced.
  5. The aforementioned tire recovery is When a predetermined change in acceleration is detected by the acceleration sensor in the aforementioned parking state, it is determined that the wheel has been stolen. The wheel monitoring system according to claim 1 or 2, wherein, in the aforementioned stationary state, if the acceleration sensor detects the change in acceleration, it is determined that the tire may have been rotated or replaced.
  6. The aforementioned in-vehicle device is In the aforementioned driving conditions, if the rotation of any of the previously registered wheels is not detected, it is determined that a tire change has been performed. The wheel monitoring system according to claim 5, which determines that the tire change has not been performed when the rotation of all of the pre-registered wheels is detected in the aforementioned driving conditions.

Description

This disclosure relates to a wheel monitoring system. Conventionally, a vehicle theft notification system is known that transmits warning information to an external location based on factors such as the change in acceleration applied to the tires exceeding a first acceleration range when the vehicle's main power is turned off and the vehicle doors are locked (see, for example, Patent Document 1). The system described in Patent Document 1 detects the air pressure of each tire using tire sensors (i.e., TPMS transmitters) attached to each tire. An on-board unit mounted on the vehicle body periodically acquires tire information, including air pressure, from the tire sensors and determines whether the change in acceleration applied to the tire exceeds a first acceleration range. Japanese Patent Publication No. 2014-141237 This is an overall configuration diagram of the wheel monitoring system according to the embodiment.This is a block diagram of the tire sensor.This is a block diagram of the in-vehicle unit.This flowchart shows the flow of control processing performed by the tire sensor.This flowchart shows the flow of the theft detection process performed by the tire sensor.This is an explanatory diagram to describe the condition of the vehicle.This flowchart shows the flow of the anti-theft alarm process performed by the tire sensor.This flowchart shows the flow of the anti-theft alarm process performed by the vehicle's in-car system.This flowchart shows the flow of the theft tracking process performed by the tire sensor.This is an explanatory diagram for describing the stolen master code.This flowchart shows the flow of the theft tracking process performed by the in-car device of another vehicle.This flowchart shows the flow of detection processes, such as tire changes, performed by the tire sensor.This flowchart shows the flow of response processes, such as tire changes, performed by the in-vehicle system.This is an explanatory diagram illustrating the relationship between door status, vehicle speed, vehicle status, bidirectional communication, acceleration change, and judgment. An embodiment of this disclosure will be described with reference to Figures 1 to 14. Figure 1 is a diagram showing a wheel monitoring system. The front and rear, left and right directions shown in Figure 1 refer to the front and rear, left and right directions of the vehicle 10. Furthermore, in the following description, when distinguishing between the four wheels 10a to 10d mounted on the vehicle 10, the four wheels 10a to 10d may be denoted as the left front wheel FL, the right front wheel FR, the left rear wheel RL, and the right rear wheel RR. The wheel monitoring system has functions for detecting wheel theft and detecting whether tires have been replaced. In other words, the wheel monitoring system functions as both a wheel theft detection system and a tire replacement detection system. As shown in Figure 1, the wheel monitoring system uses multiple tire sensors 2, an in-vehicle unit 3, a brake ECU 4, a meter 5, a door lock ECU 6, and a mobile communication device 7 to detect the theft of wheels 10a to 10d. Each tire sensor 2 and the on-board unit 3 are components of the tire pressure monitoring system (hereinafter referred to as TPMS). The TPMS uses each tire sensor 2 and the on-board unit 3, as well as information from the brake ECU 4, to automatically detect the wheel position through auto-location. The brake ECU 4 is an electronic control unit for brake control. The brake ECU 4 acquires wheel speed pulses obtained from the detection signals of wheel angle sensors 4a to 4d, which are provided corresponding to each wheel 10a to 10d, and transmits this information to the on-board unit 3 for wheel position detection. The wheel angle sensors 4a to 4d are generally called wheel speed sensors. These sensors output a signal corresponding to the tooth position of the gears that rotate with the axle as a wheel speed pulse. However, here they are used to obtain the angle at which the tire sensor 2 is located relative to the central axis of each wheel 10a to 10d, and are therefore called "wheel angle sensors." The tire sensor 2 is attached to each wheel 10a to 10d. It detects the air pressure of the tires attached to wheels 10a to 10d and stores the detected tire pressure information within a frame for transmission. The on-board unit 3 is attached to the vehicle body 11 of the vehicle 10. It receives the frame transmitted from the tire sensor 2 and performs various processing and calculations based on the information stored within it to detect the tire pressure. As shown in Figure 2, the tire sensor 2 comprises an air pressure detection unit 21, an acceleration sensor 22, a first microcomputer 23, and a tire radio 24. Each component is driven by power supplied from a battery (not shown). The air pressure detection unit 21 is equipped with a pressure sensor 21a and a temperature sensor 21b, and outputs detection signals corresponding