PURPOSE: To prevent the rounding and fraying of a blanket by press-fixing a blanket material at a cutting position in a right angle direction, cutting the blanket material in a linear state, forming linear thermally melted sections at somewhat distances from the cutting position and further fusing the cutting end surfaces.

CONSTITUTION: The cutting position of a blanket material placed on a bed 2 arranged horizontally is fixed with press plates 3 in the right angle direction, and a blow mechanism 4 and a cutting mechanism 5 are simultaneously moved along rails 7, thereby permitting to cut the blanket material with a round cutter 15 of the cutting mechanism 5 in a linear state and blow high temperature air on the blanket material from a nozzle 9 of the blow mechanism 4 to form thin linear thermally melted sections at positions somewhat apart from the cutting position for the prevention of the rounding of the blanket. A heater is simultaneously brought into contact with the cutting end surfaces to fuse the end surfaces for the prevention of the fraying of the prepared blankets.