PURPOSE: To sort articles in good order in plural drop places, by interlocking a sucking device to a conveying flat belt and preventing the following article from dropping to the same place even if the leading article drops down to said place.

CONSTITUTION: An article A is interposed between flat belts 6 and V-belts 8 and conveyed from the direction of an arrow head, if sensors 13 apply an arrival command of the article A to cylinders 10, the cylinders 10 are operated to open retainer plates 9 and drop the article A downward from opened parts. Then the following article B comes flowing, but the retainer plate 9 is not restored because of a high speed of the article B, during this time a sucking device is operated to allow suction ports 14 to suck the article B with sucking flat belts 12. Here holes of suitable size are provided in a suitable space in the flat belt 12 while notches of suitable length and width are provided in the ports 14, and the article B passes in a sucked condition without dropping, then the sensor 13 detects the article B to open a different retainer plate (not shown in the drawing) and drop the article B.