What is the principle of tire pressure detection in automobiles?

Tire pressure detection is divided into the main engine and the extension: the main engine is installed in the car, receives the signal from the extension, and sends out alarm information in time; It is installed on 4 wheel hubs in stages, which is integrated with the valve and is attached to the wheel hub, and the valve of the original car is generally replaced during installation, and the extension module monitors the tire pressure of each tire and sends relevant information to the main engine.

Tire pressure monitoring, also known as TPMS, as the name suggests, is used to monitor tire pressure, if a tire pressure is too low, it will alarm to remind the driver that there is insufficient tire pressure, to prevent abnormal wear and tear caused by lack of air.

This thing is better, it doesn't matter if you don't have it, there is no need to deliberately install it, every time before driving, see if the tires are too flat, before running a long distance, you can go to the repair shop to ask the master to help you check the tire pressure.

Generally, the lack of air on a tire on the road will increase the friction, and the vehicle is prone to unstable phenomena such as deviation, and you can feel that the vehicle is high and low on one side, so stop and get out of the car to see on the line.

In short, there is better, no does not affect it; It's installed, but you don't have to go every time to see if the 4 tires are flat.

My car has tire pressure monitoring, but most of the time I still use my vision to determine if the tire pressure is enough. Because the normal tire pressure of my car is recommended by the manufacturer, the front and rear, I use the front and rear, and the tire pressure detection tire pressure is lower than the alarm, so the visual judgment is still the main thing.

Many fans asked to talk about the principle of tire pressure detection in automobiles, and today I will disassemble two common tire pressure detection sensors on the market to let everyone understand how this thing works.

Hello, at present, the way of tire pressure monitoring is divided into indirect and direct two, indirect is to judge the length of the tire circumference by analyzing the change of wheel speed to determine whether there is a loss of air, this way is less costly. The tire pressure and temperature are directly measured by the tire pressure monitoring sensor in each tire and sent to the receiver wirelessly, which has high measurement accuracy and can prompt the most timely air loss information.

Due to the physical heat and cold shrinkage of gas, the tire pressure of automobile tires also changes with the change of ambient temperature, and the tire pressure is too high or too low will have a certain impact on the driving safety of the vehicle, so many cars are equipped with tire pressure monitoring equipment, so as to ensure that once the tire pressure is in trouble, the information can be fed back to the driver in time to avoid accidents.

At present, the tire pressure monitoring equipment on the market can be divided into two types according to their principle. Direct tire pressure monitoring equipment, it is the use of pressure sensors installed on each tire to directly measure the pressure of the tire, and then use a wireless transmitter to send the pressure information inside the tire to the receiving module, the pressure data of each tire is displayed on the vehicle instrument screen, when a tire pressure is too low or too high, the system will automatically send a prompt. Indirect tire pressure monitoring device, it is the use of vehicle wheel speed sensor to calculate the principle of speed difference, when the pressure of a tire is reduced, the weight of the vehicle will make the rolling radius of the wheel smaller, resulting in its speed is faster than other wheels, by comparing the tire speed difference, so as to achieve the purpose of monitoring tire pressure.

However, because indirect tire pressure monitoring actually monitors tire pressure by calculating the tire rolling radius, it cannot show the actual pressure of each tire, and when the pressure of four tires is too high or too low, this monitoring principle can not be found in time, and there are certain drawbacks. Both direct and indirect monitoring are only an auxiliary means, because electronic components such as sensors also have certain unreliable factors, so it is important to develop the habit of regularly checking the tire pressure.

There are two ways to detect it. The sensor is directly installed in the inflator of the tire, which detects the data of each tire respectively, and then transmits it wirelessly to the display screen, and the real-time data of tire pressure and tire temperature can be seen in front of the driver's platform; The test method is to measure the tire pressure indirectly through the speed difference between the tires. For example, when the tire pressure of one tire is low, the wheel speed in normal driving will be higher than that of other wheels, and when the speed difference reaches a certain value, the tire pressure will be alarmed to be low, and this indirect tire pressure detection method is actually an extension of the ESP function of the automobile body electronic stability system.

It is to detect the air pressure and temperature of automobile tires, and to check the early warning system such as alarm for tire abnormalities, which is mainly carried out by professional personnel.

The brands on the list of automotive tire brands are: Michelin, Goodyear, Bridgestone, Continental, Dunlop, Pirelli, etc.

Prepare the tire pressure gauge, find the original label position before testing, then block the interface, press the mouth of the tire to detect.

Most of them are tested by some instruments, which can better ensure the tire pressure and avoid problems.

Tire pressure monitoring systems are mainly divided into indirect and direct types.

The wheel speed sensor of the ABS system indirectly compares the speed difference between the tires and thus monitors the tire pressure.

The pressure sensor installed on each tire is used to directly measure the tire pressure, and the wireless transmitter sends the pressure information inside the tire to the ** receiver, and then displays the air pressure of each tire, and the system will automatically alarm when there is an air leak. The spare tire is monitored and managed by the control unit, but is not included in the information circular. The data from the wheel sensor to the control unit is transmitted via high-frequency radio.

Information exchange of vehicle peripherals is realized via the comfortable CAN bus. Each valve is equipped with a tire pressure measurement and transmitting unit that periodically sends radio signals to the tire pressure monitoring antenna and the tire pressure monitoring control unit mounted on the fenders. The tire pressure monitoring and control unit analyzes the inflation pressure of the tire and the change in pressure and sends the corresponding information to the instrument cluster, which is displayed by the driver information system.

The tire pressure monitoring system consists of five components: a tire pressure monitoring control unit and four wheel electronic systems, including tire pressure sensors.

1. There are three direct tire pressure monitoring principles for automobile tire pressure monitoring: the direct tire pressure monitoring device uses the pressure change hole force sensor installed in each tire to directly measure the air pressure of the tire, and uses the wireless transmitter to send the pressure information from the inside of the tire to the receiver module, and then displays the tire pressure data; When the tire pressure is too low or leaking, the system will automatically alarm;

2. The working principle of indirect tire pressure monitoring is that when the air pressure of a tire decreases, the weight of the vehicle will make the rolling radius of the wheel smaller, resulting in its speed being faster than that of other wheels; By comparing the speed difference between tires, the purpose of monitoring tire pressure is achieved. The indirect tire alarm system actually relies on the calculation of the tire rolling radius to monitor the air pressure;

3. Two kinds of tire pressure monitoring characteristics: These two tire pressure monitoring devices have advantages and disadvantages; Direct TPMS provides even more advanced capabilities to determine the actual instantaneous pressure inside each tire at any time, making it easy to identify faulty tires. Indirect systems are relatively low-cost, and cars that are already equipped with 4-wheel ABS (1 wheel speed sensor per tire) only need to upgrade the software; However, indirect TPMS is not as accurate as a direct system, it cannot identify faulty tires at all, and the system calibration is extremely complex, and the system may not work properly in some cases, such as when the pressure of both tires on the same axle is low.

Millions of car purchase subsidies.

The principle of automobile tire pressure monitoring: when the air pressure of a tire decreases, the weight of the vehicle will make the rolling radius of the wheel smaller, causing it to rotate faster than other wheels. By comparing the speed difference between tires, the purpose of monitoring tire pressure is achieved.

The automobile tire pressure monitoring system is a prevention and early warning system, which allows drivers to understand the operation status of tires in real time, avoid tire puncture accidents, and prolong the service life of tires. Tire pressure monitoring is mainly divided into two types: direct monitoring and indirect detection, and one is indirect monitoring by wheel speed sensors.

1. The principle of direct monitoring of tire pressure: this is that the sensor is installed in the tire and located on the valve gate, and the signal is transmitted to the receiver through direct monitoring, and finally the data is displayed. If the data is abnormal, an alarm will be generated.

2. The principle of indirect monitoring of tire pressure: indirect monitoring is to screw the sensor on like a valve cover, rather than installing it in the tire. This monitoring method also relies on the battery to power the sensor, and the signal is transmitted wirelessly, and the receiver receives it and displays it. If the data is abnormal, it will be alerted.

3. The wheel speed sensor indirectly monitors the principle of tire pressure: when a tire is out of air, its circumference will change, so the wheel speed sensor can analyze the difference in the speed of 4 tires, and the tires with the same distance of lack of air will rotate less due to the longer circumference, and the driving computer will send out an abnormal tire pressure alarm when the difference is very large.

Photo by Li Yuanli) @2019