| 摘要 |
A bending brake has a stationary table having a generally planar work surface having a straight front edge, a pivotable table having a generally planar work surface having a straight rear edge, a clamp for retaining a workpiece on the table with an end portion of the workpiece projecting forward past the front edge of the stationary table, and a pivot carrying the pivotable table for angular displacement about a pivot axis substantially parallel to the front edge of the stationary table and generally coinciding with the rear edge of the pivotable table. Supports and guides allow the pivot axis to be displaced such that the axis always lies parallel to the front edge and substantially in the plane of the work surface of the stationary table and in a rearmost position of the pivotable table its rear edge lies against the front edge of the stationary table. The pivotable table is moved about the axis while in contact with the end portion of the workpiece through a bend angle a, the workpiece has a certain thickness e, and the bend has a predetermined internal curvature radius Ri. The pivot axis and rear edge are at a spacing X from the front edge of the stationary table calculated by the formula: X=(Ri+e)xtan a/2. |
