PURPOSE: To improve the sharpness of shear, by providing a spring means for energizing at least one of a movable cutter or a fixed cutter in the direction to reduce the clearance of said cutters.

CONSTITUTION: A movable cutter 33 is energized by a spring 40 in the direction to reduce the clearance against a fixed cutter 35. Consequently even when the movable cutter 33 has abraded or a fastening screw 3 is loosened, the sharpness is improved with clean cutting cross-section. When arranging two spring means Z1, Z2 and increasing the energizing force of the spring means Z1 at the end of cut 33b side of the movable cutter 33, the sharpness is further improved.