According to the working principle, there are inertia, filtering and compounding.

Depending on the structure, there are dry and wet types.

The structure of the air filter The air filter is generally composed of an intake duct, an air filter cover, an air filter housing and a filter element.

How an air filter works.

The dry inertia air filter consists of a dust cover, a deflector, a dust outlet, and a dust collection cup. Its working principle is to use the suction generated by the cylinder during the intake stroke to generate a pressure difference between the inside and outside of the air filter. The large dust is thrown into the dust cup to complete the air filtration.

Wet inertia air filter Wet inertia air filter, also known as oil bath filter, is mainly composed of central pipe and oil pool. Its working principle is that the air enters the filter and descends at high speed along the central tube. After rushing to the oil level in the oil pool, the direction of movement suddenly changes to upward, and a rotating movement occurs. At this time, a part of the dust with a large mass is stuck in the oil due to inertia, and it is too late to reverse the direction of the air, thereby completing the filtration of the air.

Dry filter type Air filter type Air filter is mainly composed of paper filter element and gasket. Its working principle is that the air is filtered through the paper filter element when it enters the filter, so that the dust in the air is separated by the filter element or adhered to the filter element.

Wet Filter Air Gas Filter Wet filter mainly consists of metal screen immersed in oil. Its working principle is that the gas filtered by the air-oil bath is blocked by tiny dust particles when passing through the metal filter immersed in oil, and some of the dust particles adhere to it and fall into the oil pan together with the oil.

The function of the air filter is to filter out impurities or dust in the air, allowing clean air to enter the cylinder.