Anti-reflux pressurization type filtering device

The invention relates to an anti-reflux pressurization type filtering device. The filtering device comprises a grid cylinder, a filter element, screw rods and a driving motor, wherein the screw rods comprise a small screw rod and a big screw rod, the screw diameter of the small screw rod is smaller than that of the big screw rod, the small screw rod and the big screw rod are both arranged inside the filter element, and the thread surface of the big screw rod is in sealing contact with the inner wall surface of the filter element. According to the anti-reflux pressurization type filtering device provided by the invention, as the screw rods comprise the big screw rod and the small screw rod, and the filter element can rotate synchronously with the big screw rod, the small screw rod can rotate relatively to a stator barrel, so that abrasion of the big screw rod can be avoided, the small screw rod is arranged inside the stator barrel, and the filtering effect of the filter element cannot be affected. Compared with the prior art, the anti-reflux pressurization type filtering device provided by the invention overcomes the problem caused by the increasing of the distances between the screw rods and the filter element due to the abrasion of the screw rods, can avoid the operation of regularly replacing the screw rods, and greatly reduces the use cost.