PURPOSE: To widen the operating range of a shearing machine and to improve production efficiency by connecting a lower blade carrier to a control shaft, and variably adjusting the rotational position of the eccentricity of the control shaft to the rotational position of the eccentricity of a drive shaft.

CONSTITUTION: The rotational position D9 of the eccentricity E9 of a drive shaft 15 against a lower blade carrier 9 and the rotational position D20 of the eccentricity E20 against a control shaft 20 are adjusted to the bottom dead center respectively to constitute a shearing machine 1 against a moving rolled material 2. An upper blade 8 and a lower blade 10 can follow the moving direction of the rolled material 2. The rotational position D20 of the eccentricity E20 of the control shaft 20 is adjusted at 180° against the rotational position D9 of the eccentricity E9 of the drive shaft 15 to constitute the shearing machine 1 for cutting a stationary rolled material 2, and the rotational position D9 of the drive shaft 15 is adjusted to the bottom dead center and the rotational position D20 of the control shaft 20 is adjusted to the top dead center therefor. The upper blade 8 and the lower blade 10 are engaged perpendicularly to the rolled material 2 initially in the cutting process, and a small undercut is provided to generate an excellent cut face.