| 摘要 |
PROBLEM TO BE SOLVED: To make a lengthy product molding core for forming a longitudinal cavity in a product have a high rigidity to avoid the deterioration of cavity molding precision and to facilitate the extraction of the core from a molding. SOLUTION: As a locking means which regulates the relative displacement between split bodies 32, 33 and holds the whole in a prescribed shape, a spacer 34 which regulates the inward displacement of the split bodies is arranged in the space 35 of a central part, the split bodies are made inward-displacable in turn by lifting the locking means so that the split bodies are made to be able to be peeled off from a molding and extracted in the longitudinal direction. Especially, when a cavity having a rectangular cross-sectional shape is formed, it is formed from a pair of the long side split bodies facing each other with the space put between them and a pair of the short side split bodies 33 facing each other with the space put between them. |
