PURPOSE: To prevent clogging of treated material by operating an alarm in a fed state of grain culm when a target selection state is set in a selection state of treated material smaller than a set selection state of a small amount of treated material.

CONSTITUTION: A detecting means S0 of grain culm feed state discovers whether grain culms are fed to a squeezing chamber or not. When grain culms are in fed state and a target selection state is set in a selection state corresponding to an amount of treated material smaller than a set selection state corresponding to a small amount of treated material, an alarming means 34 is operated and when setting of target values by a chaff divergence setter S4 and a winnower air flow setter S5 are mistaken, an alarm is operated.