JPS57209742A - Method and device for treating recovered sand - Google Patents

Abstract

PURPOSE:To improve the treating capacity of a sieving device and to remove foreign matter more thoroughly by detecting the amt. of water contained in recovered sand, passing the sand through the sieving device only when it is larger than a constant value, and conveying the same across the screen, when it is smaller than the constant value. CONSTITUTION:When recovered sand is carried on a conveyor 1 after charging and shake-out, the amt. of water contained therein is measured with a measuring device 15. If the amt. of water is larger than a constant value, a control board 16 operates a gate cylinder 5 which in turn moves a gate plate 3 downwards to dam up the recovered sand conveyed on a conveyor 2. This sand drops below the conveyor 2 and is recovered by a conveyor 14 via a chute 13. On the other hand, when the amt. of the water contained in the recovered sand is smaller than the constant value, the plate 3 ascends and the recovered sand is charged through the conveyor 2 then through a sand feed port 10 onto the top surface of a sieving screen 7 of a sieving device 6. The greater part of the sand past the meshes of the screen 7 by receiving vibration effect is recovered to a conveyor 14 through a discharge port 12. The foreign matters such as iron pieces, core shells, iron shots and others that do not pass through the meshes of the screen 7 advances on the top surface of the screen 7 and is discharged toward the outside through a discharge port 11.