Diffusion type ion collector

The utility model discloses a diffusion type ion collector which comprises a collecting electrode, an air dust cover, a front insulating bracket, a rear insulating bracket and a polarized electrode, the collecting electrode is in a cylinder shape with two open ends; the air dust cover is arranged on the front side of the collecting electrode; the front insulation support is in a rod shape, the front end of the front insulation support is connected with the air dust cover, an insertion hole is formed in the rear end of the front insulation support, and the insertion hole and the collecting electrode are coaxially arranged. The rear insulation support is in a cylinder shape with the rear end closed and is fixed to the rear end of the collecting electrode, a counter bore is formed in the inner side face of the rear end, and the counter bore and the collecting electrode are coaxially arranged. The polarization electrode is rod-shaped, the front end of the polarization electrode is inserted and fixed into the inse