PURPOSE: To efficiently and completely remove a solid from a liquid flow stream by bearing an opposite side of a rake on a guide roller and bearing the guide roller on a cylinder rod.

CONSTITUTION: A bar screen 12 having a plurality of bars 15 and a reciprocal rake having a plurality of projections are provided to specific positions among flowing channels 20.... Then, the opposite side of the rake is borne on a guide roller, and the projections of the rake 14 are projected so that they are prevented from being directly contacted in succession between the bars 15. Then, the guide roller is borne on a cylinder rod, the rake 14 is pivoted around the upper end thereof, and the projections thereof are moved in a downwardly and outwardly arced path with respect to the screen 12. Solids and debris accumulated near the bottom of the bar screen 12 are removed by the rake 14.