JP2005162120A - Tire pneumatic pressure monitoring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent false recognition of tire pneumatic pressure drop caused by the erroneous mounting the tire to a front wheel and a rear wheel since the tire where a front wheel transmission unit and a rear wheel transmission unit are installed can be correctly mounted to a predetermined position of the front or rear wheel after they are dismounted from the wheel. <P>SOLUTION: The tire pneumatic pressure monitoring device divides the transmission unit transmitting the detection signal for the pneumatic pressure detected with a pneumatic pressure sensor detecting the pneumatic pressure of the tire mounted to a vehicle into the front wheel transmission unit mounted to the tire of the front wheel and the rear wheel transmission unit mounted to the tire of the rear wheel. The division can be distinguished from the outside in a state of tire being mounted. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a tire pressure monitoring device.

  In recent years, as a system for early detection of puncture of tires mounted on each wheel of a vehicle, the tire air pressure sensor mounted on the tire or the wheel directly detects the tire air pressure, and information on the detected tire air pressure is transmitted to the vehicle. There is known a tire pressure monitoring device that includes a transmission unit that transmits to a reception unit provided on the side, and that monitors tire pressure based on information related to tire pressure received by the reception unit (see, for example, Patent Document 1).

  In this tire pressure monitoring device, a device called an initiator is arranged in each wheel house, and an ID signal (identification information) unique to each transmission unit is provided on the vehicle side from an adjacent transmission unit by a signal emitted from each initiator. There are a system for transmitting to a receiving unit and a system simplified by omitting the initiator. In a system equipped with an initiator in each wheelhouse, the transmission unit ID for each tire position can be stored in the receiving unit each time the vehicle engine is started (ignition is turned on). The receiving unit side can grasp the relationship between the position of and the transmission unit ID attached to the tire.

  Therefore, the transmission data from the transmission unit of the other vehicle is not erroneously recognized as the transmission data from the transmission unit of the own vehicle, and the reception antenna of the reception unit is not individually provided for each wheel house, Even when one receiving antenna is shared, not only the information indicating that the air pressure has decreased based on the transmission data from the transmitting unit, but also the position of the tire where the air pressure has decreased It is possible to inform the driver. Accordingly, for example, as shown in FIG. 5A, a warning mark (ISO No. 10) 22a that warns of a decrease in tire air pressure is provided next to the speed display section in the meter panel arranged in front of the driver's seat. As shown in FIG. 5B, the position of the tire where the air pressure has decreased (the right front wheel is displayed in FIG. 5B) is colored yellow on the display 23 showing the schematic plan view of the vehicle. indicate.

  On the other hand, in the case of TPMS simplified by omitting the initiator, the relationship between the position of the tire and the transmission unit ID is shown on the receiving unit side using a dedicated device at the time of factory shipment or vehicle maintenance at a dealer. If the tire position is not changed thereafter, the receiving unit can correctly grasp the relationship between the tire position and the transmission unit ID attached to the tire. However, if tire rotation is performed, the receiving unit cannot grasp the correct relationship between the tire position and the transmission unit ID. That is, since the simplified TPMS does not include an initiator, the transmission unit ID for each tire position cannot be stored in the receiving unit each time the vehicle engine is started (ignition is turned on), and tire rotation is not performed. After being made, the receiving unit cannot grasp the relationship between the position of the tire and the transmission unit ID attached to the tire. And, because of tire rotation, the driver rarely brings the car to a maintenance facility such as a dealer. Therefore, in such a simplified TPMS, if the ID attached to the transmission data from the transmission unit is one of the four IDs stored in the factory, based on the transmission data, FIG. As shown, a warning mark (ISO No. 10) 22a that warns of a decrease in tire air pressure is displayed together with the letter 22b of TPMS, and the driver is notified only that the air pressure of any of the four wheels has decreased. However, the tire position where the air pressure is reduced is not notified.

Incidentally, some vehicles have different set air pressure values for front wheels and rear wheels (for example, front wheel 220 kPa, rear wheel 200 kPa, etc.). When the simplified TPMS is applied to such a vehicle, for example, when all four tire parts are replaced due to tire wear, the transmission unit attached to the front tire before replacement is attached to the rear wheel after replacement. The tire pressure is adjusted to the rear wheel set air pressure (200 kPa), or the front tire is moved to the rear wheel by tire rotation, and the tire air pressure is changed to the rear wheel set air pressure ( 200 kPa), the receiving unit recognizes that the transmission unit mounted on the rear wheel is still mounted on the front wheel (the relationship between the tire position stored in the factory and the transmission ID is Since it does not change), there is a risk of a malfunction that generates an unnecessary alarm when a slight drop in air pressure that does not reach the alarm air pressure occurs.
Japanese Patent No. 2639856 (Claim 1, FIG. 1)

  In view of the above circumstances, an object of the present invention is to provide a tire air pressure monitoring device that can distinguish between transmission units attached to front wheels and rear wheels at the time of tire replacement.

In order to solve the above-mentioned problem, the invention according to claim 1 is provided with an air pressure sensor that detects an air pressure of a tire mounted on a vehicle, and transmits a detection signal related to the air pressure of the tire detected by the air pressure sensor. And a receiving unit that receives the detection signal, the transmitting unit transmits identification information unique to each transmitting unit together with a detection signal related to the tire air pressure to the receiving unit, and the receiving unit receives A tire pressure monitoring device that can identify the transmission unit based on the identification information,
The transmission unit is divided into a front wheel transmission unit mounted on a front tire and a rear wheel transmission unit mounted on a rear tire, and the classification can be distinguished from the outside in a tire mounted state. Features.

  In this tire pressure monitoring device, the transmission unit is discriminated from the outside in the tire mounting state between the front wheel transmission unit mounted on the front tire and the rear wheel transmission unit mounted on the rear tire. The

  According to a second aspect of the present invention, in the tire air pressure monitoring device according to the first aspect, a division between the front wheel transmission unit and the rear wheel transmission unit is performed on a stem or a nut of the tire air pressure injection valve. It is characterized in that it can be discriminated by the attached color.

  In the tire pressure monitoring device, the front wheel transmission unit and the rear wheel transmission unit are discriminated by the color attached to the stem or nut of the tire pressure injection valve of the tire.

  According to a third aspect of the present invention, in the tire air pressure monitoring device according to the first aspect, the division between the front wheel transmission unit and the rear wheel transmission unit depends on the shape of the stem or nut of the tire air pressure injection valve. It is characterized in that it can be discriminated.

  In the tire pressure monitoring apparatus, the front wheel transmission unit and the rear wheel transmission unit are discriminated based on the shape of the stem or nut of the tire pressure injection valve.

  According to a fourth aspect of the present invention, in the tire air pressure monitoring device according to the first aspect, a division between the front wheel transmission unit and the rear wheel transmission unit is attached to a stem or a nut of the tire air pressure injection valve. It is characterized in that it can be discriminated by the symbol.

  In the tire pressure monitoring device, the front wheel transmission unit and the rear wheel transmission unit are discriminated by a symbol attached to the stem or nut of the tire pressure injection valve.

  According to the first aspect of the present invention, since the front wheel transmission unit and the rear wheel transmission unit can be distinguished from the outside, all the four tires are removed from the vehicle when the tires are replaced due to tire wear or in tire rotation or the like. Afterwards, the operator can install the tire with the front wheel transmission unit attached to the front wheel and the tire with the rear wheel transmission unit attached to the rear wheel without mistake. Thereafter, the operator can adjust the air pressure of the front wheel tire to the set air pressure of the front wheel and the air pressure of the rear wheel tire to the set air pressure of the rear wheel. Therefore, it is possible to prevent malfunction of the tire pressure monitoring device that occurs when the rear wheel transmission unit is mistakenly attached to the front wheel and the front wheel transmission unit is mistakenly attached to the rear wheel.

  According to the invention described in claim 2, the front wheel transmission unit and the rear wheel transmission unit can be distinguished from each other by the color attached to the stem or nut of the tire pneumatic pressure injection valve, and the front wheel transmission unit is attached. The tire with the rear wheel transmission unit attached to the front wheel can be attached to the rear wheel without mistake.

  According to the third aspect of the present invention, the front wheel transmission unit and the rear wheel transmission unit can be discriminated by the shape of the stem or nut of the tire pneumatic injection valve, and the tire to which the front wheel transmission unit is attached can be identified. The tire with the rear wheel transmission unit attached to the front wheel can be attached to the rear wheel without mistake.

  According to the fourth aspect of the present invention, the front wheel transmission unit and the rear wheel transmission unit can be discriminated by a symbol attached to the stem or nut of the tire pneumatic pressure injection valve, and the front wheel transmission unit is attached. The attached tire can be attached to the front wheel, and the tire to which the rear wheel transmission unit is attached can be attached to the rear wheel without mistake.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a tire pressure monitoring device (hereinafter referred to as “TPMS”) according to an embodiment of the present invention.

  The TPMS 1 shown in FIG. 1 includes front wheel transmission units 2a and 2b provided on tires FTa and FTb attached to left and right front wheels of a vehicle C, and rear wheels provided on tires RTa and RTb attached to left and right rear wheels. Transmission units 3 a and 3 b and a reception unit 4 provided on the vehicle body side of the vehicle C are provided.

  As shown in FIG. 2, the front wheel transmission units 2a and 2b and the rear wheel transmission units 3a and 3b (hereinafter abbreviated as transmission unit TM in FIGS. 2 and 3) are tires T (FTa, FTb, RTa, RTb). Is integrally formed with an air injection valve 7 provided on the rim 6 of the wheel 5 to which is attached.

  As shown in FIG. 3, the transmission unit TM is configured integrally with an air injection valve 7 attached to the rim 6. A bush 9 is inserted between the rim 8 and the air injection valve 7, and the bush 9 is sandwiched between a flange portion 11 formed to protrude from the outer periphery of the stem 10 of the air injection valve 7 and a nut 12. The air injection valve 7 is fixed. The air injection valve 7 bulges inside the tire T, and the transmission unit TM is fixed to the bulge portion. Reference numeral 13 denotes a valve cap, and 14 denotes a valve core.

  As shown in the block diagram of FIG. 4, the transmission unit TM includes a CPU 15, an air pressure sensor 16 that detects tire air pressure, and a temperature sensor 17 that detects the internal temperature of the tire. As the air pressure sensor 16, one using a pressure sensitive element such as a diaphragm or a piezoelectric element is used. The outputs of the air pressure sensor 16 and the temperature sensor 17 are converted into digital values via an A / D conversion circuit (not shown) or the like and input to the CPU 15. Further, the transmission unit TM is provided with a power source 18 to supply power to the CPU 15. Further, the transmission unit TM is provided with a transmission antenna 19, and transmits a detection signal related to the tire air pressure by the air pressure sensor 16 and the temperature sensor 17 and a detection signal related to the tire internal temperature to the reception unit 4. At this time, the transmission unit TM transmits a unique identification signal to each transmission unit (the front wheel transmission units 2a and 2b and the rear wheel transmission units 3a and 3b) together with the detection signal regarding the tire pressure and the detection signal regarding the internal temperature of the tire. . The transmission unit TM transmits a signal to the reception unit 4 by, for example, an analog method using FM modulation or a digital method using PCM modulation. For example, when the transmitted signal is a digital signal, the identification signal includes digital data indicating an ID number for identifying each transmission unit, a detection signal related to tire pressure, and a detection related to the internal temperature of the tire. The signal is transmitted to the receiving unit 4 by adding it to the front of the signal. The components such as the CPU 15, the air pressure sensor 16, the temperature sensor 17, and the transmission antenna 19 are integrally mounted on one circuit board 20 and formed into one chip.

  The detection of the tire air pressure and the like in the transmission unit TM and the transmission of the detection signal to the reception unit are performed at a predetermined timing after the engine of the vehicle C is started (ignition ON). For example, in the normal operation mode during traveling, the tire pressure is detected once every 3 to 4 seconds and the detection signal is transmitted once per minute to extend the battery life of the transmission unit TM. In the middle case, the control of the operation such as the transition to the sleep mode in which the air pressure is detected (once / 3 to 4 seconds) but not transmitted is performed. Further, if necessary, by transmitting a request signal from the receiving unit, it is possible to detect the tire air pressure or the like in the transmitting unit TM and transmit the detection signal.

  Further, as shown in FIG. 1, the receiving unit 4 is provided on the vehicle body side of the vehicle C and includes a receiving antenna (not shown) that receives a signal from the transmitting unit TM. Based on this, the tire pressure drop is monitored. At the same time, based on the received detection signal relating to the internal temperature of the tire, the internal temperature of the tire is monitored and abnormality of the tire is monitored. At this time, a transmission signal is transmitted based on a detection signal related to the tire pressure and a detection signal related to the internal temperature of the tire together with an identification signal specific to each of the received transmission units (front wheel transmission units 2a and 2b, rear wheel transmission units 3a and 3b). The tire on which the unit TM is mounted is specified. As a result, a tire whose tire air pressure falls below a predetermined threshold value is detected. When it is detected that the tire air pressure has decreased, the receiving unit 4 uses the display unit 21 to notify the driver that the tire air pressure has decreased, for example, as shown in FIG. A warning mark (ISO No. 10) 24a that warns of a decrease in tire air pressure is displayed next to the speed display section in the meter panel arranged in front of the driver's seat, and the air pressure of any of the four wheels decreases. Only inform the driver that you are doing.

At this time, in the TPMS 1 of the present invention, the transmission unit TM is divided into front wheel transmission units 2a and 2b and rear wheel transmission units 3a and 3b, and the front wheel transmission units 2a and 2b and the rear wheel transmission units 3a and 3b. Can be discriminated from the outside in a tire wearing state. For example,
(1) The color of the stem 10 of the air injection valve 7 shown in FIG. 3 or the nut 12 fitted to the stem 10 is red for the front wheel tires FTa and FTb to which the front wheel transmission units 2a and 2b are attached. The rear wheel tires RTa and Rtb to which the rear wheel transmission units 3a and 3b are attached are colored blue.
(2) The length of the nut 12 of the air injection valve 7 shown in FIG. 3 is long for the front wheel tires FTa and FTb to which the front wheel transmission units 2a and 2b are mounted, and the rear wheel transmission units 3a and 3b are mounted. The rear tires RTa and Rtb are shortened. Alternatively, the stem 10 or the nut 12 may have a different cross-sectional shape, for example, one may be a circular cross section and the other may be a polygonal cross section.
(3) A symbol for identifying either the front wheel or the rear wheel is attached to the stem 10 of the air injection valve 7 shown in FIG. 3 or the nut 12 fitted to the stem 10. For example, the nut 12 or the stem 10 is given some symbol or pattern or other identifiable symbol such as FT for the front wheel and RT for the rear wheel.

  As described above, when the transmission unit TM is divided into the front wheel transmission units 2a and 2b and the rear wheel transmission units 3a and 3b, rotation between the front and rear wheels is substantially prohibited in the tire rotation. Rotation is acceptable.

  In this way, the transmission unit TM is divided into the front wheel transmission units 2a and 2b and the rear wheel transmission units 3a and 3b, and the front wheel transmission units 2a and 2b and the rear wheel transmission unit are viewed from the appearance in a tire-mounted state. By making it possible to distinguish between 3a and 3b, after all the tires T mounted on the four wheels are removed, which and which are attached to the front wheels FTa and FTb and which and which are the rear wheels RTa , RTb can be accurately determined. Thus, even in the case of the simplified TPMS, when a tire is replaced due to wear, for example, when all four tire portions are replaced due to tire wear, the transmission unit mounted on the front wheel tire before replacement Is attached to a tire that is attached to the rear wheel after replacement, and the tire pressure is adjusted to the set pressure (200 kPa) of the rear wheel, or the tire of the front wheel is moved to the rear wheel by tire rotation, and the tire The air pressure of the rear wheel is adjusted to the set air pressure (200 kPa) of the rear wheel, and the front wheel transmission units 2a and 2b that are already mounted on the rear wheels RTa and RTb at that time are still mounted on the front wheels FTa and FTb. It is set for the air pressure of the tire mounted on the rear wheels RTa and RTb. Is prevented from performing malfunction would an alarm unnecessary pressure drop in the slight reduction in air pressure that does not lead to the threshold.

  Moreover, although the said embodiment shows the case where transmission unit TM is provided inside the rim | limb 6 of the wheel 5 which mounts the valve 7 for air injection, this invention is not limited to this embodiment, Transmission unit TM May be disposed at other locations. For example, the transmission unit TM ′ may be disposed on the inner surface of the rim 6 where the air injection valve 7 of the wheel 5 is not attached. Similarly to the transmission unit TM shown in FIGS. 2 to 4, the transmission unit TM ′ disposed on the inner surface of the rim 6 also detects the CPU 15, the air pressure sensor 16 that detects tire air pressure, and the internal temperature of the tire. A temperature sensor 17, a power supply 18 that supplies power to the CPU 15, and a transmission antenna 19 are provided.

It is a schematic diagram which shows schematic structure of TPMS in embodiment of this invention. It is sectional drawing which shows the transmission unit with which the tire was mounted | worn. It is an expanded sectional view of the transmission unit shown in FIG. It is a block diagram which shows the structure of a transmission unit. It is a figure which shows the indicator which notifies the fall of a tire pressure.

Explanation of symbols

1 TPMS (tire pressure monitoring device)
2a, 2b Front wheel transmission unit 3a, 3b Rear wheel transmission unit 4 Reception unit 7 Air injection valve 8 Rim 9 Bush 10 Stem 11 Flange 12 Nut 21 Display unit C Vehicle ECU On-vehicle controller T (FTa, FTb, RTa, RTb ) Tire TM transmission unit

Claims (4)

An air pressure sensor that detects an air pressure of a tire mounted on a vehicle, and a transmission unit that transmits a detection signal related to the air pressure of the tire detected by the air pressure sensor; and a reception unit that receives the detection signal. The unit transmits identification information unique to each transmission unit to the reception unit together with a detection signal related to the tire air pressure, and the reception unit can identify the transmission unit based on the received identification information. An air pressure monitoring device,
The transmission unit is divided into a front wheel transmission unit mounted on a front tire and a rear wheel transmission unit mounted on a rear tire, and the classification can be distinguished from the outside in a tire mounted state. A tire pressure monitoring device.   2. The tire pressure monitoring according to claim 1, wherein the front wheel transmission unit and the rear wheel transmission unit can be distinguished from each other by a color attached to a stem or a nut of a pneumatic pressure injection valve of the tire. apparatus.   2. The tire pressure monitoring device according to claim 1, wherein the front wheel transmission unit and the rear wheel transmission unit can be distinguished from each other by a shape of a stem or a nut of a pneumatic pressure injection valve of the tire.   2. The tire pressure according to claim 1, wherein the front wheel transmission unit and the rear wheel transmission unit can be distinguished from each other by a symbol attached to a stem or a nut of a pneumatic pressure injection valve of the tire. Monitoring device.

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