DRAINAGE FILTER FOR PREVENTING RUNOFF OF SEDIMENT

摘要

PURPOSE:To perform firm engagement and prevent engaged sections from falling off by forming a notchless cylindrical shell section on the periphery of a porous plate formed of synthetic resin, and by providing the outer periphery of the shell section, with engaged sheet sections extending in the inserted direction to be engaged with a drainage slot through elastic deformation. CONSTITUTION:A mesh-shaped porous plate 2 molded integrally with synthetic resin is formed at the one end of a notchless cylindrical shell section 3, and on the periphery of the porous plate 2, an engaged collar 4 extended to an external section from the outer periphery of the shell section 3 is formed. Besides, on the outer periphery of the shell section 3, the four engaged sections 5 of two pairs each at equal intervals having elasticity are arranged, and the respective engaged sections 5 are set to be of thin sheets to the shell section, and are projected to an external side in the radial direction, and are formed to be extended along the axial core direction of the shell section 3. Then, the external edges 5a of the respective engaged sections 5 are inclined to be lowered to come to the level of a front section, and its dimension is made larger than the inner diameter of the drainage slot H of a section corresponding with the engaged sections 5, and an internal peripheral wall is pressure-application-engaged with an external side.