| 摘要 |
PURPOSE:To surely give the predetermined plate thickness ratio to a molded article by a method wherein pressurized gas is blown in the interior of parison after the remaining portions of the parison excluding its predetermined sites are thinned by shifting expander members, which are abutted against the parison hung between molds so as to cool the predetermined site of the parison, and then the molds are closed. CONSTITUTION:The remaining members 7b and 7b excluding the predetermined sites 7a and 7a of parison 7 are stretched and thinned by driving expander panels 5 and 5, which are respectively abutted against the inner peripheral surface of the predetermined sites 7a of the parison 7, outwards the parison by the predetermined amount. At this time, the respective predetermined sites 7a are cooled and solidified, resulting in suppressing the flowing of the material resin of the parison and holding the sites 7a at nearly the same thickness as its original thickness during its stretching process. After that, the expander panels 5 and 5 are lowered by actuating an expander member driving device 3. Then after forming molds 3 are closed together, compressed air is blown in the parison 7 by means of a blowing device 4 so as to blow-mold the parison. |
