JP3815305B2 - Tire pressure monitoring device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention receives an identification code sent from a transmitter individually provided for each tire, a detected air pressure, and a rotation detection signal indicating that the tire is rotating by a receiver, It belongs to the technical field of a tire pressure monitoring device that distinguishes a running tire) and a non-wearing tire (spare tire) and monitors the air pressure of each wearing tire.
[0002]
[Prior art]
Conventionally, as a tire pressure alarm device, for example, the one described in Japanese Patent No. 3061047 is known.
[0003]
In this conventional publication, a tire identification code (ID: identification) sent from a transmitter that is individually attached to each tire is received by a receiver and registered within a predetermined time when it is registered. A technique for storing (registering) IDs from the higher one is described.
[0004]
[Problems to be solved by the invention]
However, in the conventional tire pressure alarm device, erroneous registration of IDs of other vehicles can be avoided in places where many vehicles are crowded, but it is also installed from non-mounted tires installed in the spare tire space of the own vehicle. If data is transmitted in the same manner as the tire, the reception frequency from the non-mounted tire becomes the same as the reception frequency from the mounted tire, and the ID of the non-mounted tire may be erroneously registered as the mounted tire. In that case, there is a possibility that the alarm of the air pressure of the mounted tire which is not registered in ID cannot be performed.
[0005]
Also, if the tire ID must be re-registered by a dealer or the like after the tire replacement, it is necessary to re-register the ID every time the tire is replaced, which is not practical.
[0006]
The present invention has been made paying attention to the above-mentioned problems, and its purpose is to distinguish between a fitted tire and a non-mounted tire, and automatically register an identification code without using a dedicated device even when the tire is replaced. An object of the present invention is to provide a tire pressure monitoring device capable of repairing .
[0007]
[Means for Solving the Problems]
In order to achieve the first object, in the invention according to claim 1,
In vehicles with multiple tires,
Air pressure detecting means for detecting the air pressure of each tire;
Tire rotation detecting means for detecting that each tire is rotating;
Transmitting means for transmitting by radio signal an identification code for each tire, the detected air pressure, and a rotation detection signal when it is detected that the tire is rotating,
Receiving means attached to a vehicle and receiving a radio signal from the transmitting means;
Storage means for storing an identification code of a mounting tire mounted on a vehicle axle as a running tire;
A tire that has been stored is compared with an identification code included in a signal in which a rotation detection signal is present. If the two identification codes do not match, the mismatched identification codes are replaced and stored again. An identification code registration means;
It is provided with.
[0010]
In the invention according to claim 2 , in the tire pressure monitoring device according to claim 1 ,
The tire rotation detection means is a centrifugal force determination means for determining the magnitude of centrifugal force due to tire rotation, and detects that the tire is rotating when the centrifugal force determination means determines that the centrifugal force is large. It is characterized by that.
[0011]
Operation and effect of the invention
In the invention according to claim 1, when the transmitting means detects the identification code for each tire, the air pressure detected by the air pressure detecting means, and the tire rotation detecting means detecting that the tire is rotating The rotation detection signal is transmitted as a wireless signal, and the receiving means attached to the vehicle receives the wireless signal from the transmitting means, and the storage means is mounted on the axle portion of the vehicle as a running tire. The tire identification code is stored. Then, the installed tire identification code registration means compares the stored tire identification code with the identification code included in the signal in which the rotation detection signal is present. Identification code registration is performed in which codes are exchanged and stored again.
[0012]
That is, the non-mounted tire (spare tire) does not rotate at all, but the mounted tire (traveling tire) detects the rotation of the tire by the tire rotation detecting means during traveling. It can be said that the identification code included in the signal in which is present is the identification code of the mounted tire. Therefore, when one wearing tire is replaced with a spare tire, comparing the tire identification code already stored as the wearing tire with the identification code included in the signal having the rotation detection signal, both identification codes are Will not match.
[0013]
Therefore, it is possible to distinguish between a mounted tire and a non-mounted tire by comparing with an already-registered identification code on the basis of an identification code included in a signal in which a rotation detection signal exists, and a newly distinguished identification code for a mounted tire. By storing, the identification code can be automatically registered again without using a dedicated device even when the tire is replaced.
[0019]
In the invention according to claim 2 , the tire rotation detecting means is a centrifugal force determining means for determining the magnitude of the centrifugal force due to the tire rotation, and when the centrifugal force determining means determines that the centrifugal force is large. Since it is detected that the tire is rotating, it is possible to reliably detect that the tire is rotating by determining the magnitude of the centrifugal force.
[0020]
DETAILED DESCRIPTION OF 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 corresponding to claims 1 and 2 .
[0021]
(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. In FIG. 1, 1 is a right front wheel tire, 2 is a left front wheel tire, 3 is a right rear wheel tire, and 4 is a left side. Rear tire, 5 spare tire, 6 right front wheel speed sensor, 7 left front wheel speed sensor, 8 right rear wheel speed sensor, 9 left rear wheel speed sensor, 10 tire pressure sensor, 11 ABS controller, 12 is an AT controller, 13 is a tire air pressure alarm controller, and 14 is a low air pressure warning lamp.
[0022]
The right front wheel speed sensor 6, the left front wheel speed sensor 7, the right rear wheel speed sensor 8, and the left rear wheel speed sensor 9 detect the wheel speeds of the front and rear wheels 1, 2, 3, and 4, and the wheel speed sensor signals are detected. Input to the ABS controller 11.
[0023]
The tire pressure sensor 10 is attached to each of the road wheels of the front and rear tires 1, 2, 3, 4 and the spare tire 5, and detects the tire pressure of each tire, and the ID (identification code) of each tire. The detected tire pressure and the centrifugal force switch signal are transmitted to the tire pressure alarm controller 13 by radio signals.
[0024]
The ABS controller 11 inputs wheel speed sensor signals from the wheel speed sensors 6, 7, 8, 9 and outputs vehicle speed information (vehicle speed, vehicle acceleration / deceleration, wheel speed) to the tire pressure alarm controller 13. .
[0025]
The AT controller 12 determines a shift position based on a switch signal from an inhibitor switch (not shown), and outputs shift position information to the tire air pressure alarm controller 13.
[0026]
The tire air pressure alarm controller 13 distinguishes between the front and rear wheel tires 1, 2, 3, and 4 that are mounted tires and the spare tire 5 that is a non-mounted tire, and the front and rear wheel tires 1, 2, 3, and 4 that are mounted tires. When it is determined that at least one of the tire pressures is reduced, a lamp lighting command is output to the air pressure reduction warning lamp 14.
[0027]
FIG. 2 is a detailed view showing the tire pressure sensor 10 and the tire pressure alarm controller 13 of the tire pressure monitoring device of the first embodiment.
[0028]
The tire pressure sensor 10 is opened (OFF) in a region where the acting centrifugal force is small and closed (ON) in a region where the centrifugal force is large, with a pressure sensor 10a (pneumatic pressure detecting means) that detects tire pressure (internal pressure). A centrifugal force switch 10b (tire rotation detection means and centrifugal force determination means), an ASIC 10c that is an application specific integrated circuit, a transmitter 10d and a transmission antenna 10e (transmission means) are configured. Then, with the opening / closing of the centrifugal switch 10b installed to ensure the battery life as a trigger, a long transmission interval (1 hour) in a region where the vehicle speed including stop is low, and a short transmission interval in a region where the vehicle speed is higher than that. The transmission cycle is changed to two stages such as (1 minute), and modulated pressure value information from the pressure sensor 10a, individual tire ID information, and a centrifugal force switch signal are transmitted using electromagnetic waves. As a tire rotation detection means (centrifugal force discrimination means), a centrifugal force sensor is used instead of the centrifugal force switch 10b, and the ASIC 10c breaks whether the output value from the centrifugal force sensor is a predetermined value or more. May be.
[0029]
The tire pressure warning controller 13 includes a 5V power supply circuit 13a, a receiving antenna 13b and a receiving circuit 13c (receiving means) for receiving transmission data from the transmitting antenna 10e of the tire pressure sensor 10, and vehicle speed information from the ABS controller 11. Vehicle speed information input circuit 13d, shift position information input circuit 13e for inputting shift position information from AT controller 12, received data from receiving circuit 13c, and input information from both input circuits 13d and 13e. A microcomputer 13f that inputs and performs arithmetic processing according to a predetermined control law, an EEPROM 13g (storage means) that is a read-only memory capable of electrically erasing stored information for performing ID registration, and a pressure of a mounted tire in received data Judgment value and tire pressure warning finger when pressure drops Configured with a warning lamp output circuit 13h that outputs a pressure drop warning lamp 14.
[0030]
Next, the operation will be described.
[0031]
[Installation tire ID registration calculation process]
FIG. 3 and FIG. 4 are flowcharts showing the flow of the ID registration calculation process of the attached tire executed by the tire air pressure alarm controller 12, and each step will be described below.
[0032]
In step S1, shift position information is read from the AT controller 11, and in the next step S2, it is determined whether the shift shift position is a stop shift position (P range or N range). If it is a stop shift position, the process proceeds to step S3. In step S3, the flag when the storage of the four mounted tires is completed is reset to 0, and the process returns. That is, nothing is performed in the stop shift position.
[0033]
If the travel shift position (D range, 1st speed fixed range, 2nd speed fixed range, R range) is determined in step S2 instead of the stop shift position, the process proceeds to step S4 to determine whether the flag is 1 (4 It is determined whether or not the storage of the mounted tire has been completed. If the flag is 1, the process ends and the process ends.
[0034]
If the flag in step S4 is 0, the process proceeds to step S5, where the wheel speeds VFL, VFR, VRL, VRR from the vehicle speed information input circuit 13d are the wheel speeds at which the centrifugal switch 10b is turned on (for example, 15km / h) is determined, and if the speed is less than the wheel speed at which the centrifugal force switch 10b is turned on, the process returns, and if the speed is higher than the wheel speed at which the centrifugal force switch 10b is turned on, the process proceeds to step S6. .
[0035]
In step S6, every time this step S6 elapses, the counter N is added to N + 1. That is, by multiplying the number represented by the counter N and the set time of one control cycle, the elapsed time from the start of the ID registration calculation process is obtained, and the size of the counter N is the start of the ID registration calculation process. The elapsed time from
[0036]
In step S7, it is determined whether or not the counter N is less than the set counter α. If the counter N is greater than or equal to the set counter α, the process proceeds to step S8, and if the counter N is less than the set counter α, The process proceeds to step S9.
[0037]
In step S8, an alarm is issued that any of the four mounted tires is abnormal in transmission. In other words, the storage of the four mounted tires is not completed (flag = 1) even though a sufficient time has elapsed since the start of the ID registration calculation process, and any of the four mounted tires is transmitted. Judge as abnormal. The transition from step S7 to step S8 corresponds to the transmission means abnormality determination means of claim 3.
[0038]
In step S9, data from the tire pressure sensor 10 (modulated pressure value information from the pressure sensor 10a, individual tire ID information, centrifugal force switch signal) is received.
[0039]
In step S10, it is determined whether or not the ID of the received data matches any of the five IDs stored in advance. If none of the IDs match, a return is made and stored in advance. If it matches any of the five IDs, the process proceeds to step S11.
[0040]
In step S11, it is determined whether the centrifugal force switch signal of the received data is ON. If the centrifugal force switch signal is ON, the process proceeds to step S12. If the centrifugal force switch signal is OFF, the process proceeds to step S15. .
[0041]
In step S12, since the centrifugal force switch signal is ON, it is determined that the data ID received in step S10 is the ID of the attached tire.
[0042]
In step S13, it is determined whether or not the ID determined as the mounted tire in step S12 matches any of the four IDs stored as the mounted tire. If they match, the process returns. If it does not match any of the four IDs, the process proceeds to step S14.
[0043]
In step S14, the ID determined not to match any of the four IDs in step S13 is newly stored (registered) as the ID of the attached tire, and the process proceeds to step S18.
[0044]
In step S15, since the centrifugal force switch signal is OFF, it is determined that the data ID received in step S10 is the ID of the non-wearing tire.
[0045]
In step S16, it is determined whether or not the ID determined as the non-mounted tire in step S15 matches any of the four IDs stored as the mounted tire. If they match, the process proceeds to step S17. If it does not match any of the four IDs, the process reaches the end.
[0046]
In step S17, when it matches with any of the four IDs stored as attached tires in step S16, the ID determined as a non-attached tire among the IDs currently stored as attached tires is deleted. Control goes to step S18.
[0047]
In step S18, it is determined whether or not the number of IDs stored as wearing tires is four. If the number of IDs stored as wearing tires is four, the process proceeds to step S19, and flag = Set 1 In addition, when the number of IDs stored as attached tires is less than 4, the process returns.
[0048]
[Installation tire ID registration]
For example, as shown in FIG. 5, before tire replacement, the right front wheel tire was ID1, the left front wheel tire was ID2, the right rear wheel tire was ID3, the left rear wheel tire was ID4, and the spare tire was ID5. After the tire replacement, the ID registration function of the mounted tire will be described in the case where the right rear wheel tire is ID5 and the spare tire is ID3.
[0049]
First, the ID3 that was the right rear wheel tire before the tire replacement and became the spare tire after the tire replacement will be described. When the shift shift position condition (step S2) and the vehicle speed condition (step S5) are satisfied, 3 and 4, the process proceeds to step S 1 → step S 2 → step S 4 → step S 5 → step S 6 → step S 7 → step S 9 → step S 10 → step S 11. Since the signal is OFF, the process proceeds from step S11 to step S15. In step S15, the tire is determined as a non-mounted tire (spare tire), and is stored as a mounted tire before tire replacement in the next step S16. ID among IDs (ID1, ID2, ID3, ID4) Therefore, the process proceeds to step S17. In step S17, ID3 is deleted from the four IDs (ID1, ID2, ID3, ID4) stored as the mounted tire, and then step S18 is performed. To return.
[0050]
Next, ID5, which is a spare tire before the tire replacement and becomes the right rear wheel tire after the tire replacement, will be described. When the shift shift position condition (step S2) and the vehicle speed condition (step S5) are satisfied, the vehicle is traveling. 3 and FIG. 4, the process proceeds from step S 1 → step S 2 → step S 4 → step S 5 → step S 6 → step S 7 → step S 9 → step S 10 → step S 11. Since the centrifugal force switch signal is turned on, the process proceeds from step S11 to step S12. In step S12, the tire is determined to be a mounted tire, and in the next step S13, ID5 is stored as a mounted tire before tire replacement. One of the four IDs (ID1, ID2, ID3, ID4) Therefore, the process proceeds to step S14. In step S14, ID5 is newly stored as the ID of the mounted tire, and the ID number stored as the mounted tire is newly added instead of ID3 being deleted. If the number is four, in step S18, it is determined that the number of IDs stored as mounted tires is four, the process proceeds to step S19, the flag is rewritten from 0 to 1, and then step S1 → step. The process proceeds from S2 to step S4, and since flag = 1 is determined in step S4, the ID registration calculation process for the attached tire is terminated.
[0051]
In this way, it is possible to distinguish between a fitted tire and a non-mounted tire depending on whether the centrifugal force switch signal of the data received in step S11 is ON or OFF, and erase the newly identified non-mounted tire ID and newly By storing the IDs of the mounted tires that have been distinguished, the IDs can be automatically re-registered without using a dedicated device even when the tires are replaced.
[0052]
[Transmission abnormality judgment action]
If any of the transmitting means (transmitter 10d and transmitting antenna 10e) provided on the four mounted tires has a transmission failure, the number of IDs determined to be mounted tires whose centrifugal force switch signal is ON is In step S18, the number of IDs stored as mounted tires does not become four in step S18 because the number of mounted tires mounted on the axle portion of the vehicle as a running tire does not match (4). The flow from S18 to step S1, step S2, step S4, step S5, step S6, and step S7 is repeated.
[0053]
If the flow of step S18 → step S1 → step S2 → step S4 → step S5 → step S6 → step S7 is repeated a plurality of times while the flag remains 0, the time limit condition of step S7 is not satisfied, and the step The process proceeds from S7 to step S8, and based on the determination that an abnormality has occurred in the transmission means of any of the mounted tires, the driver is informed of the transmission abnormality by an alarm.
[0054]
That is, when all the transmission means are normal, the number of IDs determined to be mounted tires whose centrifugal force switch signal is ON matches the actual number of mounted tires. For this reason, if there is an abnormality in the transmission means of any of the mounted tires, the number of IDs determined to be mounted tires for which the centrifugal force switch signal is ON decreases, and the tires mounted as running tires Will not match the number.
[0055]
Therefore, based on the number of running tires that are actually mounted, the transmission means for any of the mounted tires is compared with the number of IDs that are determined to be mounted tires for which the centrifugal force switch signal is ON. Can be judged. In addition, by waiting for a sufficient time for transmission, it is possible to reliably determine the abnormality (transmission impossible) of the transmission means of any of the mounted tires, and it is reliably determined that the transmission means is abnormal. In some cases, an alarm can inform the driver.
[0056]
Next, the effect will be described.
[0057]
(1) When the centrifugal force switch signal of the data received in step S11 is ON, it is determined that the tire is mounted in step S12, and when the centrifugal force switch signal of the data received in step S11 is OFF, In step S15, it is determined that the tire is a non-mounted tire. In step S14, the newly determined tire ID is stored. In step S17, the newly determined tire ID is deleted from the mounted tire ID. For this reason, it is possible to distinguish between mounted tires and non-mounted tires and automatically re-register IDs without using dedicated equipment even when the tires are replaced.
See steps S11 to S17 of the flowcharts shown in FIGS.
[0058]
(2) If the number of IDs determined to be fitted tires for which the centrifugal force switch signal is ON does not match the number of fitted tires (four) fitted to the axle of the vehicle as a running tire, the fitted tires Since the ID registration completion flag is not set, it is possible to determine the abnormality of the transmission means of any of the mounted tires.
See step S11 of the flowcharts shown in FIGS.
[0059]
(3) Progress in a situation where the number of IDs determined to be fitted tires for which the centrifugal force switch signal is ON does not match the number of worn tires (four) fitted to the vehicle axle as a running tire When the time reaches a predetermined time or more, the process proceeds from step S7 to step S8, so that it is possible to reliably determine abnormality (non-transmission) of the transmission means of any of the mounted tires.
See steps S6 and S7 in the flowcharts shown in FIGS.
[0060]
(4) Progress in a situation where the number of IDs determined to be fitted tires with the centrifugal force switch signal ON does not match the number of fitted tires (four) fitted to the vehicle axle as a running tire If the time reaches a predetermined time or more, the process proceeds from step S7 to step S8, where a transmission abnormality is alarmed. Can be informed as a warning.
[0061]
(5) The tire rotation detecting means is a centrifugal force switch 10b that is operated by a centrifugal force caused by the tire rotation, and the tire pressure is detected when the centrifugal force switch signal is ON. It is possible to reliably detect that the tire is rotating by using an existing centrifugal force switch 10b in the sensor 10.
[0062]
(Other examples)
The tire pressure monitoring device of the present invention has been described based on the first embodiment. However, the specific configuration is not limited to the first embodiment, and is described in each claim of the claims. Design changes and additions are permitted without departing from the scope of the invention.
[0063]
For example, in the first embodiment, an example in which a centrifugal force switch is used as a means for detecting that each tire is rotating has been shown. However, each wheel speed sensor is used to transmit each wheel speed signal. Also good.
[Brief description of the drawings]
FIG. 1 is an overall view showing a vehicle to which a tire pressure monitoring apparatus according to a first embodiment is applied.
FIG. 2 is a detailed view showing a tire pressure sensor and a tire pressure alarm controller of the tire pressure monitoring device of the first embodiment.
FIG. 3 is a flowchart 1 showing a flow of an ID registration calculation process for a mounted tire executed by a tire air pressure alarm controller of the tire air pressure monitoring device of the first embodiment.
FIG. 4 is a flowchart 2 showing the flow of an ID registration calculation process for a mounted tire executed by a tire pressure alarm controller of the tire pressure monitoring device of the first embodiment.
FIG. 5 is a diagram showing the ID of each tire before and after tire replacement.
[Explanation of symbols]
1 right front wheel tire 2 left front wheel tire 3 right rear wheel tire 4 left rear wheel tire 5 spare tire 6 right front wheel speed sensor 7 left front wheel speed sensor 8 right rear wheel speed sensor 9 left rear wheel speed sensor 10 tire pressure sensor 10a pressure sensor (Air pressure detection means)
10b Centrifugal force switch (tire rotation detection means, centrifugal force discrimination means)
10d transmitter (transmission means)
10e Transmitting antenna (transmitting means)
11 ABS controller 12 AT controller 13 Tire pressure alarm controller 13b Receiving antenna (receiving means)
13c Receiving circuit (receiving means)
13g EEPROM (memory means)
14 Low air pressure warning lamp

Claims (2)

In vehicles with multiple tires,
Air pressure detecting means for detecting the air pressure of each tire;
Tire rotation detecting means for detecting that each tire is rotating;
Transmitting means for transmitting by radio signal an identification code for each tire, the detected air pressure, and a rotation detection signal when it is detected that the tire is rotating,
Receiving means attached to a vehicle and receiving a radio signal from the transmitting means;
Storage means for storing an identification code of a mounting tire mounted on a vehicle axle as a running tire;
A tire that has been stored is compared with an identification code included in a signal in which a rotation detection signal is present. If the two identification codes do not match, the mismatched identification codes are replaced and stored again. An identification code registration means;
A tire pressure monitoring device comprising: In the tire pressure monitoring device according to claim 1,
The tire rotation detection means is a centrifugal force determination means for determining the magnitude of centrifugal force due to tire rotation, and detects that the tire is rotating when the centrifugal force determination means determines that the centrifugal force is large. A tire pressure monitoring device characterized by that.

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