Prefilter used for air intake system of fork-lift truck

The utility model discloses a prefilter used for an air intake system of a fork-lift truck, comprising an air inlet hood which is internally fixed with vortex-shaped blades which consist of a main blade and an auxiliary blade; a prefilter hood cylinder which is rotatably arranged in the air inlet hood is arranged above the vortex-shaped blades; the external side wall of the prefilter hood cylinder is fixed with cyclone blades; the lower end of the prefilter hood cylinder is communicated with an air inlet; and the side wall at the lower part of the air inlet hood is provided with a dust and air outlet. In the utility model, the dusts and impurities in the air can be filtered so that the combustion-supporting air in the air intake system of the whole fork-lift truck is cleaner, sufficient volume efficiency is generated in the gas cylinder, and the combustion effect of the engine is improved.