PURPOSE: To pulverize liquid flow in the intermeshing parts of gear couples and to form an emulsion of high concn. with good efficiency by providing multiple stages of gears to a driving shaft, and providing multiple stages of gears intermeshing with the gears of the driving shaft to a driven shaft in parallel with the driving shaft as well.

CONSTITUTION: Propeller-like stirring vanes 8 are mounted to the driving shaft 6 in an agitating tank 1, and gears AWE of dissimilar diameters are fitted pivotally to the shaft 6 below a bearing 4. The gears (a)W(e) intermeshing with each of the gears AWE are stuck to a driven shaft 11 erected in parallel with the shaft 6. Since the respective gear couples are rotated at different speeds by the above-mentioned arrangement, the liq. flow ascending in the tank 1 is pulverized in the intermeshing parts thereof by the rotation of the vanes 8, whereby an emulsion of a high concn. having good dispersibility is formed with good efficiency.