| 摘要 |
In a bending machine, metal strip (42) is bent by a sequence of steps including longitudinal advance of the strip (42) alternating with bending of the strip by a movable tool (18) which engages and deflects the strip when the latter is restrained against longitudinal movement. Provision is made for checking or inspecting the permanent angular deformation of each bend applied to the strip, to take account of the tendency of the metal strip to spring back after bending. Compensation for spring-back is achieved by use of a previously described characteristic relating displacement of the bending tool to the resultant permanent angle of bend applied to the strip. Further compensation is provided to remove an error which can arise if the bending tool is movable along a line of action spaced from the point of bending of the strip by an amount greater than the incremental advance of the strip. |
