PURPOSE: The titled device in which a plate regulating the direction of fluid is demountably fixed to the bottom clearer to allow clearer fluffs and flying fluffs to move along the upper surface of the roller beam without flying upward.

CONSTITUTION: The plate for regulating the direction of fluid is demountably set at an appropriate position in the pot clearer. The first regulator 29 prevents the fluid from rolling up from the jetting nozzle 22 of the air-supplying pipe 21 and the second regulator 30 guides the fluid prevented in its rolling-up upward at an angle to the space 33. Flying fluffs and clearer fluffs are carried by the fluid efficiently, when the height of the space 33, 1, is set to 15W25mm.