PURPOSE: To make possible to convey grains smoothly and securely, by interconnecting externally a vertical type screw conveyor and a horizontal type conveyor without constricting the path for conveying the grains.

CONSTITUTION: An upper flank of a cylindrical case 8 of the vertical type screw conveyor 7 is communicated with a bottom flank of a cylindrical case 1 of the horizontal type screw conveyor 11 through a path A provided coaxially with a horizontal axis (X), a screw shaft 14 of the horizontal type screw conveyor 7 projects from the upper end of the cylindrical case 8, while a screw shaft 15 of the horizontal type screw conveyor 11 projects from the bottom of the cylindrical case 12, and gears 16, 16 attached to the projected ends of the screw shafts 14, 15 are interconnected through an idle gear 17 fitted and geared on the path A.