| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for correcting the diametric expansion of a ring casting for a tire mold with high precision using an expander while suppressing the mackerel folding phenomenon of a crown R shape. SOLUTION: In the method for correcting the diameter and roundness of the ring casting cast and manufactured so as to become small by 0.02-0.2% in its diameter with respect to a target diameter at the same time using the expander, the external force F applied to the ring casting and the diametric dimension increase quantityΔD of the inner or outer diameter part of the ring casting are continuously measured and, from a curve obtained when the external force F is taken on a vertical axis and the diametric dimension increase quantityΔD is taken on a horizontal axis, the valueΔDs of an X-axis at the time of intermittent crossing of the straight line of a gradientαpassing the leading end point C of the curve and the X-axis from the point of time exceeding an elastic limit point B is calculated. When the target diametric increase quantity is set toΔDn in the ring casting, the external force F is divided at a point D becomingΔDs=ΔDr+ΔDn to set the inner diameter of the ring casting after division to a target diametric dimension. COPYRIGHT: (C)2006,JPO&NCIPI |
