| 摘要 |
PURPOSE:To constitute the title technique so that a difference in level is not generated on a connecting part between an extrusion molded part and pattern molded part, by a method wherein at the time of molding of the pattern molded part by adjoining to an extrusion hollow molded product along with vulcanization by fitting a semiproduct of the extrusion hollow molded product into a mold, a core comprised by forming a spiral groove in the outside of the core to be inserted into a hollow part of the semiproduct is used. CONSTITUTION:At the time of molding of pattern molded parts 3a, 3b along with vulcanization by fitting semiproducts 1a, 1b of extrusion molded products into molds 6a, 6b, cores 4a, 4b obtained by forming spiral grooves 5a, 5b in the outside of cores to be inserted into hollow parts 2a, 2b of the semiproduct 1a, 1b are used. Repelling force Q from the inside opposing to clamping pressure P from the outside is unified and mitigated all over the surface by inserting the cores 4a, 4b having the spiral grooves 5a, 5b in the outside into the hollow parts 2a, 2b. Therefore, thicknesses of the semiproducts 1a, 1b can be absorbed between the sprial grooves 5a, 5b of the cores 4a, 4b and it is hard to generate a difference in level on a connecting surface M-M. |
