To solve the problem that when a slurry-state mortar after the interior of the drum of a ready mixed concrete vehicle is cleaned is stored in an external tank, an underwater pump is used to reuse the mortar as kneaded and mixed water, most of the solid components of fine sands, etc. is not sucked, and is retained in the bottom of the tank, and to enable to move the pump without enlarging the size of the pump.
The lower part of the storage tank is narrowed, a screw conveyor is installed, the solid component precipitated near the conveyor is integrated in the pumping chamber of a conical shape dug down from the bottom of the tank, stirred and mixed in a solution component, and transferred to the measuring tank of the upper part of a mixer by a pump. The slurry-state mortar thrown from the receiving chamber of the measuring tank flows down to a stirring chamber. Further, the slurry-state mortar is reversed and moved from the stirring chamber to the returning chamber of the upper part thereby to stir the solid component. The solution component is circulated to the pumping chamber from the returning chamber by overflowing, and the solid component is stirred and mixed by its water flow.
ISHIHARA YUKITO
ISHIDA MAKOTO