| 摘要 |
A tip-bend forming method for machining pockets while a curved, plate-shaped workpiece is in a flattened state, without depending on novel machining equipment, wherein the curve radius of the plate-shaped workpiece after the pockets have been machined is prevented from becoming smaller than a completed curve radius due to spring-in. A plate-shaped workpiece (2) forming method for post-machining pockets (3) into the curved inner surface of the workpiece (2) while the plate-shaped workpiece (2), which has been curved by a curve-forming machine (10), is in a flattened state, the forming method having: a curve-forming step (A) for estimating in advance the amount that spring-in will cause the curve radius of the plate-shaped workpiece (2) to shrink after machining of the pockets (3) compared to before the machining thereof, setting a net curve radius (Ro) obtained by adding a curve-radius shrinkage amount (R 1 ) caused by spring-in to the completed curve radius (R) of the plate-shaped workpiece (2), and forming the curve in the plate-shaped workpiece (2) so as to achieve the net curve radius (R 0 ); and a pocket-machining step for flattening the curved, plate-shaped workpiece (2), and post-machining pockets (3) therein. |
