SHEARING METHOD, SHEARING DEVICE, AND SHEARING FACILITY
FIG3B is another schematic illustration comparable to FIG2B, showing the operation of the typical shearing machine and the behavior of the workpiece  FIG3C is still another schematic illustration comparable to FIG2C, showing the operation of the typical shearing machine and the behavior of the workpiece
In the state shown in FIG3B, the work-hardening of the material inside the workpiece 6 occurs in a region R2B. It should be noted that, though the region R1B shown in FIG2B is enlarged at the lower side of the workpiece 6, there is no such enlargement in the region R2B shown in FIG3B.  In the state shown in FIG3C, the work-hardening of the material inside the workpiece 6 occurs in a region R2C. It should be noted that, though the region R1C shown in FIG2C is further enlarged at the lower side of the workpiece 6, there is no such enlargement in the region R2C shown in FIG3C. In other words, the region R2C is a relatively narrow region extending along the plane connecting the lower blade 21 and the upper blade 31.
schematic
21
lower blade
61
fractured surface
31
upper blade
['1. A shearing method for applying a shear force on a plate-shaped workpiece in a thickness direction to cut the workpiece, the method comprising: starting application of the shear force on the workpiece with a clearance between action points in a surface direction orthogonal to the thickness direction of the workpiece; applying the shear force after starting applying the shear force until a fractured surface is created on the workpiece; and increasing the clearance depending on a deformation of the workpiece in the thickness direction after starting applying the shear force until the fractured surface is created on the workpiece.', '2. The shearing method according to claim 1, wherein the method is performed using a plurality of shearing machines each comprising a lower blade and an upper blade movable in the thickness direction of the workpiece relative to the lower blade, a clearance defined between the lower blade and the upper blade along the surface direction of the workpiece being different in each of the plurality of shearing machines, and in increasing the clearance, the shear force is sequentially applied on the workpiece from one of the plurality of shearing machines whose clearance is small to one of the plurality of shearing machines whose clearance is large.']