Take my car Outlander as an example to continue to talk about a little knowledge of automatic induction wiper!

Dear old irons, I'm here again. I'm not very busy recently. I just want to write a post to study my car and share my learning experience with my riders! Outlander is equipped with this function-induction wiper, also known as automatic wiper. ? Simply put, the induction wiper can sense the size of raindrops through the rainfall sensor, automatically adjust the running speed of the wiper, and provide a good view for drivers, thus greatly improving the convenience and safety of driving in rainy days. ? At present, there are two mainstream sensors in the market, namely optical sensors and capacitive sensors. ? Let's talk about the principle of optical sensor first: it works according to the refraction principle of light. There is a light-emitting diode in the optical sensor, which emits a cone-shaped beam through the front windshield. When there is no rain on the windshield and it is dry, almost all the light will be reflected to an optical sensor; When it rains, there will be rain on the windshield, and some light will deviate, causing the total amount of light received by the sensor to change, thus detecting the existence of rain. The larger the area where an optical sensor can receive reflected light, the more detailed information it can obtain. The optical sensor is very accurate, and can even accurately determine the number of raindrops falling in the sensing area. ? Early optical sensors were as follows:

On a sunny day, there are no raindrops, and the light refracted by the emission tubes on both sides is the same, which will not work!

As shown in the figure, when raindrops appear, the balance is broken and the automatic wiper starts to work! This problem caused by accuracy now appears in another form! (The picture above is from Baidu)

This picture is the corresponding optical structure in principle, an infrared emitting tube and an infrared receiver, which are then converted into electrical signals and transmitted to the ECU unit.

This principle is easy to explain, avoiding the above-mentioned situation that the refraction position of both sides is the same.

This is the circuit diagram of this form.

The rain sensor sends the wiper control LIN message to the master node controller BCM according to the rain situation, and the master node controller controls the wiper to perform corresponding actions. So as to realize the automatic control of the wiper.

The other form is capacitive sensor: it is mainly designed by using the huge difference of dielectric constant between water and glass, in which the dielectric constant of water is 80 and that of glass is 2. Usually, two parallel finger-shaped metal plates are placed between the inner and outer layers of the windshield, and a group of finger-shaped metal plates are staggered without touching other finger-shaped metal plates. When the windshield is in a dry state, a dielectric is formed between the outer surface of the windshield and each group of finger metal plates. When the windshield gets wet, the dielectric constant of the windshield will change differently according to the amount of water in contact with the windshield. But this will lead to inaccurate results with the increase of use time!

Simply put, when it doesn't rain, there is no conductive medium and no electrical signal. When it rains, it acts as a dielectric to conduct electricity, and then there is a signal.

Let's take a look at my car, the use of the Outlander automatic wiper and the switch!

It can only be reflected in rainy days, hahaha! It's just raining!

Raise your head. One?

Double flashing of parking reflects the passing vehicles in rainy days.

Side?

Want a big ass?

Ok, after reading my little Ou, it's time to talk about Outlander's automatic wiper!

There are details in the manual!

Matters needing attention, that is, if the automatic wiper works in sunny days, then you should check whether the sensor position is dirty, and pollutants will affect the function of the automatic wiper!

The content is as shown in the picture, borrowing pictures, being lazy!

For example, you don't have to panic in this rainy day, and you don't have to control the wiper yourself. Automatic wipers can be easily done! Pay full attention to driving.

Due to the limitation of my knowledge level, the analysis is here at present. If there are any mistakes, please forgive me for guidance. Thank you, Lao Tie! Offer the beautiful scenery after the rain! This is the beauty of 3 18!

Yuzhong bridge

Yuzhong bridge 2

Be surrounded by fog

fairyland