External-force type back wash lamination filter

The utility model discloses an external-force type back wash lamination filter which comprises an upper gland, a shell, a base, a water inlet, a water outlet and a blow-off pipe. The external-force type back wash lamination filter is characterized in that two ends of the shell are connected with the upper gland and the base; the filter element of the lamination filter is arranged in the shell; the filter element is composed of a top plate, a water guide pipe with holes, a laminate, a spring, a bottom fixing disk, a T-shaped piston and a baffle with holes; the upper gland is provided with an external-force device; the external-force device is connected with a top plate on the top of the filter element by a screw gearing; the lower end of the top plate is pressed on the laminate; the lower end of the laminate is pressed on the moving baffle; the filter element of the lamination filter is sheathed in the base; the bottom end of the base is provided with the water outlet; the outer wall of the base is provided with the water inlet and the blow-off pipe; and the water inlet and the blow-off pipe are communicated with the inside of the base. Compared with the prior art, in the external-force type back wash lamination filter disclosed by the utility model an external-force action is adopted to carry out back wash on the filter so as to ensure the smooth back wash process. The external-force type back wash lamination filter has the advantages of simple structure and obvious back wash effect, and is convenient to operate.