JP2004359122A - Tire air pressure monitoring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire air pressure monitoring device requiring no monitoring whether or not registration of a tire discrimination symbol is required expect in the case where the registration of the tire discrimination symbol is truly required and capable of outstandingly reducing probability that the tire discrimination symbol is erroneously registered. <P>SOLUTION: The tire air pressure monitoring device is provided with tire air pressure sensors A, B, C, D mounted to the tires 1, 2, 3, 4 respectively; a receiving means mounted to a vehicle side; and a tire discrimination symbol registration means for registering ID. A vehicle stop detection step S4 for detecting vehicle stopping and a vehicle height sensor 12 for detecting vehicle height are provided. The ID registration means monitors variation of the vehicle height after the vehicle stops and carries out the registration of the ID only when the vehicle height is varied to an increase direction by set vehicle height or more. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technical field of a tire pressure monitoring device for individually registering a tire identification code (ID) corresponding to a position of a tire mounted on a vehicle in order to accurately monitor a tire pressure of only a vehicle wheel. Belongs to.
[0002]
[Prior art]
With the automatic ID registration logic of the conventional tire pressure monitoring device, when registering the automatic ID, after initially registering a total of four types of IDs on the front and rear wheels, each time the same ID is received, the ID table is counted up and registered. When the receiver receives a different ID from the ID of the ID, a learning function of counting with the spare ID table is provided. If the count of the spare ID table is larger than the maximum value of the ID table, the learning function is performed. It describes that an ID is registered and the ID registration is updated (for example, see Patent Document 1).
[0003]
Also, the transmitter of the currently mounted traveling wheel is determined (= ID discrimination) by checking the ID of the traveling wheel and the ID of the spare wheel registered in advance and the reception time of the radio wave. (For example, see Patent Document 2).
[0004]
[Patent Document 1]
JP 2000-71726 A [Patent Document 2]
JP-A-9-210827 [Problems to be solved by the invention]
However, in the conventional tire pressure monitoring device, since the number of received radio waves is monitored as needed, for example, when a transmitter fails and does not emit radio waves, another vehicle may be adjacent due to traffic congestion or the like. If the vehicle runs sideways by the own vehicle, the ID of the transmitter of the adjacent vehicle may be registered by mistake.
[0005]
In addition, since it is determined when the ID registration is necessary based on the stop condition, it is not possible to determine whether the vehicle has just stopped at a traffic light stop or the like or has replaced the tire with a rotation or spare tire. The number of times of monitoring increases more than necessary.
[0006]
The present invention has been made in view of the above problem, and the number of times of monitoring the necessity of registration of the tire identification code is eliminated except when the tire identification code is really required to be registered. It is an object of the present invention to provide a tire pressure monitoring device capable of greatly reducing the probability.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention,
Tire pressure detecting means attached to each of a plurality of tires mounted on the vehicle, receiving means attached to the vehicle side, and a tire identification code for registering the tire identification code of each tire by storing and updating the memory in a memory Registration means, and a tire pressure monitoring device comprising:
Vehicle stop detection means for detecting vehicle stop, vehicle height detection means for detecting the vehicle height,
The tire identification code registering means monitors the change in the vehicle height after the vehicle stops, and registers the tire identification code only when the vehicle height changes in a direction of increasing the vehicle height or more.
[0008]
【The invention's effect】
In the tire pressure monitoring device of the present invention, in the tire identification code registration means, after the vehicle is stopped, the change in vehicle height is monitored, and only when the vehicle height has changed in the increasing direction by more than the set vehicle height, Since the registration of the tire identification code is performed, the number of times of monitoring the necessity of the registration of the tire identification code is eliminated except when the registration of the tire identification code is really required, and the probability of erroneously registering the tire identification code is greatly reduced. be able to.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment for realizing a tire pressure monitoring device according to the present invention will be described based on a first embodiment shown in the drawings.
[0010]
(First embodiment)
First, the configuration will be described.
FIG. 1 is an overall view showing a vehicle to which the tire pressure monitoring device of the first embodiment is applied. As shown in FIG. 1, a vehicle to which the tire pressure monitoring device is applied includes a left front wheel tire 1, a right front wheel tire 2, a left rear wheel tire 3, a right rear wheel tire 4, and tire pressure sensors A, B, C, and D. (Tire air pressure detecting means), a tuner (1), (2), (3), (4) (receiving means) with an antenna, a tire air pressure alarm controller 5, a display 6, and a low air pressure warning lamp 7.
[0011]
The tire pressure sensors A, B, C, and D are mounted on the road wheels of the front and rear tires 1, 2, 3, and 4, respectively. A tire identification code), detected pressure data (tire pressure information), and the like are transmitted as radio signals to tuners (1), (2), (3), and (4) with antennas.
[0012]
The tuner (1), (2), (3), and (4) with the antenna receives each information transmitted from the tire pressure sensors A, B, C, and D and inputs the information to the tire pressure alarm controller 5.
[0013]
The tire pressure alarm controller 5 registers the ID of each tire individually, displays the tire pressure information of each of the tires 1, 2, 3, and 4 of the front and rear wheels specified by the ID registration on the display 6, and If it is determined that at least one of the tire pressures of the tires 1, 2, 3, and 4 has decreased, a lamp lighting command is output to the pressure decrease warning lamp 6.
[0014]
FIG. 2 is a detailed view showing the tire pressure monitoring device of the first embodiment. The tire pressure sensors A, B, C, and D are open (OFF) in a region where the applied centrifugal force is small and closed (ON) in a region where the centrifugal force is large, together with a pressure sensor 10a (pressure sensor unit) for detecting the tire pressure. ), An ASIC 10c which is an application-specific integrated circuit, a transmitter 10d, and a transmitter antenna 10e (transmitter). The opening and closing of the centrifugal switch 10b installed to secure the battery life is used as a trigger, and a long transmission interval (1 hour) is used in a region where the vehicle speed is low including a stop, and a region where the vehicle speed is higher than that (for example, 40 km / h) h), the transmission cycle is changed to two stages, such as a short transmission interval (1 minute).
[0015]
As shown in FIG. 2, the tuners (1), (2), (3), and (4) with antennas are provided with a receiving antenna 11a for receiving transmission data from the tire pressure sensors A, B, C, and D. , And a tuner 11b as a receiving circuit.
[0016]
As shown in FIG. 2, the tire pressure warning controller 5 receives a 5V power supply circuit 5a, data received from each of the tuners 11b, and performs various information processing with a microcomputer 5b. An EEPROM 5c, which is a read-only memory capable of electrically erasing stored information, and a display drive circuit for outputting a display drive command for displaying tire pressure information of each tire 1, 2, 3, 4 to the display 6 based on received data. 5d, a warning lamp output circuit 5e for judging the pressure value of the mounted tire in the received data and outputting a tire pressure warning command to the pressure drop warning lamp 7 when the pressure drops, and temporarily storing the tire identification code IDn and the like. And a RAM (random access memory) 5f.
[0017]
The microcomputer 5b receives vehicle height information from a vehicle height sensor 12 (vehicle height detecting means) and vehicle speed information from a vehicle speed sensor 13, and uses these information to determine whether ID registration is necessary. Can be
[0018]
Next, the operation will be described.
[0019]
[Automatic ID registration process]
FIG. 3 is a flowchart showing the flow of the automatic ID registration processing for each tire executed by the tire pressure alarm controller 5 of the first embodiment. Each step will be described below (tire identification code registration means).
[0020]
In step S1, it is determined whether or not the ignition switch is ON, that is, the power supply state of the vehicle is monitored. If YES, the process proceeds to step S2. If NO, it is determined whether or not the ignition switch is ON. Repeat the decision.
[0021]
In step S2, it is determined whether or not the vehicle speed V is equal to or higher than a set vehicle speed (for example, 40 km / h), that is, it is monitored whether or not the vehicle is in a traveling state in which the transmission is reliably performed by the operation of the centrifugal force switch 10b. In the case of, the process proceeds to step S3, and in the case of NO, the process returns to step S1.
[0022]
In step S3, the process enters the ID registration mode, stores the IDs of the tires 1, 2, 3, and 4 in the EEPROM 5c, and proceeds to step S4.
This ID registration is performed, for example, by the tuner (1), (2), (3), and (4) with an antenna receiving data, measuring the ID and the reception level of a received signal, and measuring the radio wave intensity received simultaneously with the ID. Are compared, and the IDs received by the receiving means having the largest radio field intensity are individually registered as IDs for the respective tires 1, 2, 3, and 4.
[0023]
In step S4, it is determined whether or not the vehicle speed V is 0 km / h, that is, a vehicle stop state is detected. If YES, the process proceeds to step S5, and if NO, the process proceeds to step S11 (vehicle stop detection). means).
[0024]
In step S5, the timer t is started based on the detection of the vehicle stop state, and the process proceeds to step S6.
[0025]
In step S6, based on the vehicle height information from the vehicle height sensor 12, it is determined whether or not the vehicle height change amount has become equal to or greater than the set vehicle height Lmm in the vehicle height increasing direction, that is, a jack-up determination is made. In this case, the process proceeds to step S7, and if NO, the process returns to step S4.
Here, the set vehicle height Lmm is set based on a vehicle height increasing direction change amount of the vehicle height due to the jack-up.
[0026]
In step S7, it is determined whether or not the timer t has exceeded a set time required for tire replacement (for example, 10 minutes). If YES, the process proceeds to step S8, and if NO, the process returns to step S6.
[0027]
In step S8, it is determined whether or not the vehicle speed V is equal to or higher than a set vehicle speed (for example, 40 km / h), that is, it is monitored whether or not the vehicle is in a running state in which transmission is reliably performed by the operation of the centrifugal force switch 10b. In the case of, the process proceeds to step S9, and in the case of NO, the vehicle speed determination in step S8 is repeated, and the process waits until the vehicle speed V reaches the set vehicle speed.
[0028]
In step S9, the apparatus enters the ID re-registration mode, stores and updates the IDs of the tires 1, 2, 3, and 4 in the EEPROM 5c, and proceeds to step S10.
This ID registration is performed in the same manner as in step S3, for example, by comparing the magnitudes of radio waves received at the same time as the IDs, and identifying the IDs received by the receiving means having the largest radio wave strengths in the tires 1, 2, and 2, respectively. In steps 3 and 4, the IDs are individually registered.
[0029]
In step S10, it is determined whether the re-registration of the ID has been completed. If YES, the process proceeds to step S11. If NO, the process returns to step S8.
[0030]
In step S11, the air pressure of each of the tires 1, 2, 3, and 4 is detected using the ID stored and set in the EEPROM 5c, and the process proceeds to step S4.
[0031]
[Automatic ID registration action]
When the ignition switch is turned on, the vehicle is started, the vehicle enters the running mode, and when the vehicle speed V exceeds 40 km / h, the flow proceeds to step S1 → step S2 → step S3 in the flowchart of FIG. In the registration mode, the IDs of the tires 1, 2, 3, and 4 are stored in the EEPROM 5c. That is, when the vehicle speed V exceeds 40 km / h for the first time from the start of traveling, registration of the ID is performed in the subsequent traveling mode so that the air pressure of each of the tires 1, 2, 3, and 4 can be detected.
[0032]
At the time of traveling after the ID registration, in the flowchart of FIG. 3, the flow proceeds to step S1 → step S2 → step S3 → step S4 → step S11, and then the flow of step S4 → step S11 is repeated. , The air pressure of each of the tires 1, 2, 3, and 4 is detected using the ID stored and set in the EEPROM 5c.
[0033]
When the vehicle is temporarily stopped due to a signal stop or the like during traveling after the ID is registered, the flow proceeds to step S4 → step S5 → step S6 in the flowchart of FIG. 3, and in step S6, the increasing direction of the vehicle height changes. Although the amount is checked, the change in vehicle height is small when the vehicle is stopped normally, so that the flow returns from step S6 to step S4, and the flow of step S4 → step S5 → step S6 is repeated. Then, when the vehicle starts because the signal has turned green, the flow proceeds to step S4 → step S11, and then the flow of step S4 → step S11 is repeated. In step S11, the ID stored in the EEPROM 5c is set. Is used to detect the air pressure of each of the tires 1, 2, 3, and 4.
[0034]
Then, when a new tire or a tire is replaced by rotation, the flow proceeds to step S4 → step S5 → step S6 in the flowchart of FIG. 3, and in step S6, the vehicle is jacked up in the tire replacement work. When the amount of change in the height increasing direction is equal to or greater than Lmm, the flow proceeds from step S6 to step S7, and the flow from step S6 to step S7 is repeated. Then, in step S7, when a minimum time (for example, 10 minutes) required for tire replacement has elapsed, the process proceeds to step S8, and after the tire replacement, the running mode is set, and the vehicle speed V is reliably transmitted by the operation of the centrifugal force switch 10b. Wait until the vehicle speed is set (for example, 40 km / h). When the vehicle speed V becomes equal to or higher than the set vehicle speed, the process proceeds from step S8 to step S9. In step S9, the ID re-registration mode is entered, and the IDs of the tires 1, 2, 3, and 4 are stored and updated in the EEPROM 5c. If it is determined in step S10 that the re-registration of the ID has been completed, the process proceeds to step S11. In step S11, each of the tires 1, 2, 3, and 4 is stored in the EEPROM 5c by using the newly stored ID. Is performed.
[0035]
Next, effects will be described.
[0036]
(1) A pressure sensor 10a that is attached to each of a plurality of tires 1, 2, 3, and 4 mounted on a vehicle, and detects a tire pressure, and converts at least the detected tire pressure into a radio signal together with an ID of each tire. Tire pressure sensors A, B, C, and D having a transmitter 10 and a transmission antenna 10e for transmitting a radio signal, and are mounted on the vehicle side to receive radio signals from the tire pressure sensors A, B, C, and D. A vehicle stop detecting step S4 for detecting a vehicle stop in a tire pressure monitoring device including a receiving unit and an ID registering unit for registering an individual ID for each of the tires 1, 2, 3, and 4 by storing and updating in an EEPROM 5c. And a vehicle height sensor 12 for detecting the vehicle height. The ID registration means monitors a change in the vehicle height after the vehicle stops, and sets the vehicle height in a direction to increase the vehicle height. Only when the vehicle height is changed or more, the ID is registered after that. Therefore, the number of times of monitoring the necessity of ID registration is eliminated except when the ID registration is really required, and the probability of incorrect ID registration is greatly increased. Can be reduced.
[0037]
(2) The ID registration means monitors a change in the vehicle height after the vehicle stops, and when the vehicle height changes in a direction of increasing the vehicle height or more, sets the time required for tire replacement based on the change in the vehicle height increasing direction. After the lapse of time, in order to register the ID, even if there is a temporary or instantaneous increase in vehicle height when the vehicle is stopped due to a cause other than jack-up, the condition is that the vehicle height increase state continues for a while. , It is possible to make a reliable jack-up decision.
[0038]
(3) The ID registering means monitors a change in the vehicle height after the vehicle stops, and when the vehicle height changes in a direction of increasing the vehicle height or more, the ID registration means determines a set time required for tire replacement from the change in the vehicle height increasing direction. If the set vehicle speed at which the tire pressure sensors A, B, C, and D surely transmit the individual IDs of the respective tires becomes equal to or higher than the set vehicle speed, the IDs are registered. ID registration can be performed based on reliable ID transmission from the tire pressure sensors A, B, C, and D having the force switch 10b.
[0039]
(4) The receiving means are tuners (1), (2), (3), and (4) with antennas set in the vicinity of each of the plurality of tires (1, 2, 3, 4) by the number of tires. When the plurality of IDs are received by the tuner (1), (2), (3), (4) with each antenna, the tire identification code registering means determines the magnitude of the radio wave intensity received simultaneously with the IDs. In comparison, since the ID received by the tuner with the antenna having the largest radio field intensity is registered, the trouble of setting the tire pressure delicately at the time of tire replacement or rotation is eliminated, and each of the four wheels is eliminated. The reliability of ID registration corresponding to the position can be improved.
[0040]
As described above, the tire pressure monitoring device of the present invention has been described based on the first embodiment, but the specific configuration is not limited to the first embodiment, and is described in each claim of the claims. Changes and additions of the design are allowed without departing from the gist of the present invention.
[0041]
For example, in the first embodiment, the receiving means sets the tuners (1), (2), (3), and (4) with antennas near the respective tires 1, 2, 3, and 4; Although the example in which the ID registration is performed according to the magnitude of the radio wave intensity has been described, the ID registration may be performed according to the number of times of reception of the transmitted radio wave.
[Brief description of the drawings]
FIG. 1 is an overall view showing a vehicle to which a tire pressure monitoring device according to a first embodiment is applied.
FIG. 2 is a detailed view showing the tire pressure monitoring device of the first embodiment.
FIG. 3 is a flowchart showing the flow of an automatic ID registration process for each tire executed by the tire pressure alarm controller of the first embodiment.
[Explanation of symbols]
Reference Signs List 1 left front wheel tire 2 right front wheel tire 3 left rear wheel tire 4 right rear wheel tire A, B, C, D Tire pressure sensor (tire pressure detecting means)
(1), (2), (3), (4) Tuner with antenna (receiving means)
5 Tire pressure alarm controller 5c EEPROM
5f RAM
6 Display 7 Low air pressure warning lamp 10a Pressure sensor (pressure sensor section)
10b Centrifugal switch 10c ASIC
10d transmitter (transmitter)
10e Transmission antenna (transmission unit)
11a Receiving antenna 11b Tuner

Claims (4)

A pressure sensor unit that is attached to each of a plurality of tires mounted on the vehicle and detects each tire pressure, and a transmitting unit that transmits at least the detected tire pressure with a radio signal together with a tire identification code for each tire, Tire pressure detecting means having
A receiving unit attached to the vehicle side, for receiving a wireless signal from the tire pressure detecting unit,
Tire identification code registration means for registering the tire identification code of each of the tires by updating the storage in a memory,
In a tire pressure monitoring device equipped with
Vehicle stop detection means for detecting vehicle stop, vehicle height detection means for detecting the vehicle height,
The tire identification code registering means monitors a change in the vehicle height after the vehicle stops, and registers the tire identification code only when the vehicle height changes in a direction of increasing the vehicle height or more, and thereafter. Tire pressure monitoring device. 2. The tire pressure monitoring device according to claim 1, wherein the tire identification code registration unit monitors a change in the vehicle height after the vehicle stops, and detects a change in the vehicle height in a direction in which the vehicle height increases. A tire pressure monitoring device, wherein a tire identification code is registered after a set time required for tire replacement has elapsed from a change in the increasing direction. 3. The tire pressure monitoring device according to claim 2, wherein the tire identification code registering means monitors a change in the vehicle height after the vehicle stops, and detects a change in the vehicle height in a direction in which the vehicle height increases. When the set time required for tire replacement has elapsed from the change in the increasing direction, and the set vehicle speed at which the tire pressure detecting means reliably transmits the individual tire identification code for each tire is equal to or higher than the tire identification code, A tire pressure monitoring device characterized by performing registration. The tire pressure monitoring device according to any one of claims 1 to 3,
The receiving means, in the vicinity position of each of the plurality of tires, set the number of tires,
The tire identification code registering means, when registering the tire identification code, when each receiving means receives a plurality of tire identification codes, compares the magnitude of the radio wave intensity received simultaneously with the tire identification code, A tire pressure monitoring device for registering a tire identification code received by a receiving unit having the largest size.

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