JPH07257119A - Device for warning of air pressure reduction for each tire with the use of electromagnetic wave - Google Patents

Abstract

PURPOSE:To provide a device for warning of air pressure reduction for each of tires with the use of an electromagnetic wave signal in order to recognize one of the tires which reduces its air pressure CONSTITUTION:In a tire air pressure reduction warning device in which a monitor confirms an air pressure reduction in accordance with a signal which is transmitted to a receiver from a tire air pressure checker attached to a tire of a vehicle, devices 21 to 2n on the transmitter side, transmit signals which are delivered from the tire air pressure checkers and which are modulated waves having the same carrier wave frequency modulated at different time intervals. Only one signal receiver 4 on the signal receiving side, receives the modulated signal, and demodulates the same so as to recognize one of the tires which reduces its air pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decompression warning device for each tire, which can accurately transmit which tire is to a driver by means of electromagnetic waves when the tire air pressure of an automobile is reduced.

[0002]

2. Description of the Related Art When the tire pressure of an automobile is insufficient, there are many inconveniences such as an increase in rolling resistance of the tire, a decrease in high-speed durability, and a decrease in vehicle maneuverability. Therefore, it is necessary to constantly research the tire pressure.

As a means for this, an air pressure checker is attached to an air valve of an automobile tire, a transmitter is incorporated in the air pressure checker, a receiver and a monitor are installed and placed in a driver's seat, and the tire checker with reduced air pressure is removed. A signal can be transmitted, a receiver can receive the signal, and the monitor can visually recognize that the tire pressure is insufficient. An example is the actual Kaihei 3-1.
It is described in Japanese Patent Publication No. 00502.

FIG. 5 is an explanatory view showing an example of a device for warning a decrease in tire air pressure described in the above publication as a prior art. In FIG. 5, when the housing of the sensing unit 40 is attached to the tire valve, air normally flows from the tire into the atmospheric pressure chamber 41 to have a high pressure, and the diaphragm 42 expands toward the atmosphere chamber side. Then, the electric contact 44 is pushed against the biasing spring, and the switch 45 is opened. Then, the electric current from the power supply 47 is not supplied to the radio wave transmission circuit 46, and the alarm signal is not transmitted from the radio wave transmission circuit.

However, when the tire air pressure decreases and falls below the range of the appropriate value corresponding to the elasticity of the biasing spring, the diaphragm retracts and the electrical contact 44 is pushed back by the biasing spring and the switch 45 Is closed. Then, the current from the power supply 47 is supplied to the radio wave transmission circuit 46, and the alarm signal is transmitted. The radio wave receiving circuit 48 receives the alarm signal and issues an output command to the sound generating circuit 49 to generate an alarm for abnormal tire pressure reduction.

Next, the tire air pressure is constantly measured by using a combination of a DC power source generating part using a ceramic element or the like inside the tire and a capacitance type pressure detecting element, and there is an abnormality such as a decrease in air pressure. A device that transmits an electric signal to the outside is known as a trade name run flat tire.

[0007]

In the prior art, when the fact that the tire pressure has decreased is transmitted to the driver's seat by a radio wave transmission circuit or the like, in the technique described in the above-mentioned "Actual Kaihei Gazette", the air pressure once drops. Then, an alarm signal is immediately issued, but the driver cannot immediately identify which tire of his / her vehicle has reduced air pressure. In order to identify the tire with reduced air pressure and transmit the tire position as a signal, it is necessary to manufacture and adjust the signal processing circuit for each tire, which makes the signal processing circuit very complicated and therefore the alarm device is expensive. There was a drawback.

Further, the element that has emitted the alarm signal consumes a large amount of its power source, and the transmission of the alarm signal cannot be stopped until the driver performs a corresponding process. Therefore, the usable time of the power source is short. It was

Further, when the air pressures of a plurality of tires are simultaneously lowered, the alarm signals are generated at the same time, so that the signals cannot always be received normally. Even if it can be received normally, immediately after completion of the handling process for one tire, it is immediately confirmed whether the process is bad and the checker attached to the replaced tire is bad, or other tires are defective. Was difficult.

Next, in the case of run-flat tires, when the air pressures of a plurality of tires decrease at the same time, the transmission signals are of the same type, so that they may interfere with each other.
The signal cannot always be received normally.

An object of the present invention is to improve the above-mentioned drawbacks and to provide a decompression warning device for each tire by an electromagnetic wave signal for individually identifying that the air pressure has been reduced for a plurality of tires, with a relatively simple structure. Especially.

[0012]

According to a first aspect of the present invention, a tire pressure checker mounted on a tire of a vehicle transmits a signal indicating that the air pressure has decreased, and the signal is received by a receiver and confirmed by a monitor. In the tire decompression alarm device, the signal transmission side device is configured to transmit a modulated wave in which the output signal of each tire pressure checker is modulated at the same carrier frequency at different time intervals, and the signal reception side device is , The modulated wave is received by only one receiving device, and is decoded to identify the tire with reduced air pressure.

According to a second aspect of the present invention, the output signal of each tire pressure checker according to the first aspect of the invention is transmitted by including a predetermined identification code for identifying each tire, and the signal is transmitted to the signal receiving side. The device is configured by identifying the tire whose pressure has been reduced by the identification code.

According to a third aspect of the present invention, the tire pressure checker is fixedly arranged in the tire tube including the electromagnetic wave transmitting antenna, and the operating power source is a generator that generates power as the vehicle travels. ing.

According to a fourth aspect of the present invention, there is provided a tire voltage warning device, wherein a tire air pressure checker mounted on a tire of a vehicle sends a signal indicating that the air pressure has decreased, is received by a receiver and is confirmed by a monitor. The device on the signal transmitting side transmits a modulated wave in which the carrier frequency that makes the output signal of each tire pressure checker different for each tire is modulated, and the device on the signal receiving side receives the modulated wave by different receiving units. Then, the decoding is performed to identify the tire whose air pressure has decreased, and the tire is constructed.

The invention described in claim 5 corresponds to the invention described in claim 3 applied to the invention described in claim 4.

[0017]

According to the first aspect of the present invention, the tire pressure checker mounted on the tire of a vehicle such as an automobile sends a signal indicating that the air pressure has decreased, and therefore, the devices for each tire on the sending side are different from each other. The carrier frequency is modulated at each time interval. In other words, the carrier frequencies of the outer tires are the same and the modulation time intervals are different. Since the device on the signal receiving side is commonly used by the tire pressure checkers, the tires are identified by the difference in the time intervals when they are decoded.

According to a second aspect of the present invention, since the output signal of each tire pressure checker according to the first aspect of the present invention is transmitted by including an identification code for identifying each tire, the signal receiving section receives the modulation time. Along with the difference in spacing, the identification code can be used to accurately identify the tire.

According to the third aspect of the present invention, a generator disposed in the tire tube is used as an operating power source for each tire pneumatic checker. Since the generator is generating electric power as the vehicle travels and the antenna is also inside the tire, the tire pressure checker can be arranged without becoming a foreign substance when viewed from the outside of the vehicle.

According to the fourth aspect of the present invention, since the output signal of each tire pressure checker is a modulated wave using a carrier frequency different for each tire, the structure of the receiving section becomes complicated, but the pressure reduction of the air pressure is reduced. It is possible to easily and quickly identify the tires that have worn.

Since the invention described in claim 5 corresponds to the invention described in claim 3 being applied to the invention described in claim 4, the operation is the same.

[0022]

1 is a diagram showing an embodiment of the invention described in claim 1. In FIG. In FIG. 1, transmission side devices 21 to 2n are installed for each tire of a vehicle, and a normal passenger car uses four devices. The transmitting side device 21 incorporates a tire pressure checker 10-1 such as a tire valve mounting type, an operating power supply 11-1, a timer circuit 12-1, and a transmission circuit 13-1, and indicates the tire pressure by the carrier frequency F. Modulated electromagnetic wave 3 including data
1 is being sent. The other transmission side device incorporates the same circuit element as that of the device 21 and transmits the electromagnetic wave of the same carrier frequency F. The electromagnetic waves 31 to 3n are extracted by the air pressure checkers 10-1 to 10-n with respect to the data indicating the tire air pressure, and then, as indicated by 31A and 32A to 3nA, the timers are set so that the intervals of the modulated data are different from each other depending on the transmitting side device. The circuit 12-1 is adjusted and applied to the transmission circuits 13-1 to 13-n to perform the modulation operation. Modulated electromagnetic waves are transmitted from each transmission circuit.

As the transmitting side device, a device having almost the same structure is used, and the pressure-reduced tire can be identified only by electronically adjusting the internal circuit. It is not necessary to manufacture the alarm device separately for each tire.

In the receiving side device 4, each transmitting side device 21
To 2n, the modulated electromagnetic waves 31 to 3n are commonly received, and the transmitting side device that transmits the electromagnetic waves is identified by the above-mentioned modulation interval. Then, the monitor 5 displays the position of the transmitting device, that is, the position of the tire whose air pressure has decreased.

When the tire pressure checkers 10-1 to 1n-1 detect that the air pressure has been reduced, the modulated electromagnetic wave 3
Since 1 to 3n are modulated and transmitted at different time intervals for each tire, even if a plurality of tires may be decompressed at the same time and signals are simultaneously transmitted, if some time elapses, reception is performed. The device on the side decodes a different signal for each tire, so that the driver can reliably handle it.

The tire pressure checker is not limited to the valve mounting type, but may be of a type using a pressure sensor. 2 is a diagram showing an embodiment of the invention described in claim 2,
It is described that an electromagnetic wave is modulated by a signal from a pneumatic checker. In FIG. 2, the modulation data is C1,
C2 −, and A1, A2, − are distinguished by signals from the air pressure checker when the air pressure is normal and when the air pressure is reduced. B1, B2, ... Show tire identification codes, and are signals that can identify which tires are on the front, rear, left and right of the vehicle. Since the subscripts 1, 2, and so on are given respectively as time passes, C1, C2, and so on are the same signal unless the driver takes action.

If the signal shown in FIG. 2 is used, the receiving side device only uses a simple decoding circuit for B1 and B2, and what tire is transmitting the data of A1 and A2. It is possible to grasp quickly and surely.

FIG. 3 is a diagram showing an embodiment of the invention described in claim 3, and is a perspective view (A) showing the signal transmitting side device with the tire tube of the vehicle removed, and a case of the signal transmitting side device. The perspective view (B) is shown with the cover removed. In FIG. 3 (A), the device 60 on the signal transmitting side is mounted together with the case in the inter-flange recess of the vehicle tire wheel 61 and mounted on the tire wheel 61 by the tightening band 62 before the tire tube is mounted. Device 60
Since the tire tube is assembled after it is attached to the tire wheel 61, it is not necessary to perform maintenance and inspection until the tire air pressure becomes smaller than a predetermined value.

Next, FIG. 3 (B) is a perspective view of the device 60 on the signal transmitting side with the case cover removed.
Various circuits and elements are mounted on. Their composition is
The power generation unit 65 uses a generator using a ceramic piezoelectric vibrator, and also has a rectifying / smoothing circuit built therein. Pressure sensor 6
6 is a tire pressure checker. The microcomputer 67 performs signal processing. The timer / signal calculator 68 assists in data processing. The high frequency signal unit 69 processes the electromagnetic wave signal. The antenna 70 transmits an electromagnetic wave.

Next, the operation will be described. The power generation section 65 is configured to generate power as the vehicle travels. The pressure sensor 66 directly checks the tire air pressure, and outputs different signals when the tire air pressure is normal or when it is reduced. The microcomputer 67 is a central processing unit for processing digital signals, and is supplied with the output of the power generation unit 65 and performs processing for applying the output signal of the pressure sensor 66 to the timer / signal calculation unit 68. The timer / signal operation unit 68 performs an operation for converting the output of the pressure sensor 66 into a modulation signal, and provides a predetermined modulation signal interval as shown in FIG. 1 or sets a tire position identification code to set the modulation signal. Adding,
Further, processing for controlling the distribution time of the DC output of the power generation unit 65 to each unit is performed.

The high frequency signal section 69 oscillates a carrier electromagnetic wave signal of frequency F and processes the data from the timer / signal operation section 68 as a modulation signal. An electromagnetic wave is radiated from the antenna 70.

Next, FIG. 4 is a diagram showing an embodiment of the invention described in claim 4. In FIG. 4, the transmission side devices 21 to 2n are substantially the same as those shown in FIG. However, the carrier frequencies F are made different from each other and selected as F1 to Fn. The receiving side device is provided corresponding to the carrier frequency of the transmitting side device like 71 to 7n. In the receiving device, monitor 5
In FIG. 4, 1 to 5n are shown to be provided corresponding to each receiving device. For the carrier frequencies F1 to Fn, even if the modulation intervals are the same for the signals from the pneumatic checkers, the tire identification is possible because the receiving side device that receives them has a different modulation interval. Of course, it is easier for the driver to identify if the modulation interval is different.

In the receiving side device, the monitor is the receiving side device 7.
It can be commonly installed for 1 to 7n. In that case, insert a mechanical switch that connects the receiving device to the monitor. Alternatively, an electronic device is used as the switch.

[0034]

As described above, according to the present invention, when an abnormal state in which the tire pressure is reduced occurs, an alarm including the tire position identification information is accurately transmitted by "radio" transmission. Can be identified quickly. Even if a plurality of tires are decompressed at the same time, they can be easily identified. The driver can drive safely without being aware of tire pressure. Furthermore, if a generator that generates electric power while the vehicle is running is used as the power source of the alarm device, there is no need to worry about wiring for the power source, and there is no need to worry about power consumption.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the invention described in claim 1.

FIG. 2 is a diagram showing an embodiment of the invention described in claim 2;

FIG. 3 is a diagram showing an embodiment of the invention described in claim 3;

FIG. 4 is a diagram showing an embodiment of the invention described in claim 4;

FIG. 5 is an explanatory diagram showing a conventional technique.

[Explanation of symbols]

 10-1 to 10-n Tire pressure checker 21 to 2n Signal transmission side device 31 to 3n Electromagnetic wave of carrier frequency F 4 Signal reception side device 5 Monitor

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G01M 17/02

Claims (5)

[Claims] 1. A tire decompression alarm device, which transmits a signal indicating that the air pressure has decreased from a tire pressure checker attached to a tire of a vehicle and is received by a receiver and confirmed on a monitor, wherein the device on the signal transmitting side is The output signal of each tire air pressure checker is configured to transmit a modulated wave in which the same carrier frequency is modulated at different time intervals, and the signal receiving side device is configured to transmit the modulated wave by only one receiving device. A decompression warning device for each tire by electromagnetic waves, which receives and decodes and identifies a tire whose air pressure has been reduced. 2. An output signal of each tire pressure checker according to claim 1 is transmitted by including a predetermined identification code for identifying each tire, and a device on the signal receiving side uses the identification code to identify the tire. A decompression alarm device for each tire characterized by being identified. 3. The tire pressure checker is equipped with a generator for generating power as the vehicle travels as an operating power source, and is fixedly arranged inside the tire tube including an electromagnetic wave transmitting antenna. 2. A decompression warning device for each tire by the electromagnetic wave described in 2. 4. A tire pressure reduction alarm device, which transmits a signal indicating that the air pressure has decreased from a tire pressure checker attached to a tire of a vehicle and is received by a receiver and confirmed on a monitor, wherein the device on the signal transmitting side is , The output signal of each tire pressure checker transmits a modulated wave in which a carrier frequency different for each tire is modulated, and the device on the signal receiving side receives the modulated wave by different receiving units, decodes it, and reduces the air pressure. A decompression warning device for each tire by electromagnetic waves, characterized in that each tire is identified. 5. The tire pressure checker according to claim 4, wherein the tire pressure checker is equipped with a generator for generating power as the vehicle travels as an operating power source, and is fixedly arranged inside the tire tube including an electromagnetic wave transmitting antenna. Decompression warning device for each tire by electromagnetic waves.