| 摘要 |
PROBLEM TO BE SOLVED: To realize a round two-layer rice cake forming vessel having nearly uniform thickness by a method wherein the one side of the cross section of a pipe-like parison for direct blowing is thicker than the other side. SOLUTION: In a section, which is normal to the longitudinal direction of a pipe-like parison 3, under the condition that a vertical center line passing through the left and right center positions from outside is set at a base, one side is designed to be thicker than the other side. In addition, the thinner other side is arranged to the side, towards which a parting line is biased, of a mold 2 and the thicker onesa side is arranged to the side opposite to the side, to which the thinner other side is arranged. Under the condition just mentioned above, a compressed air is blown in the parison 3. By bringing the parison into close contact with the inner wall of both the split molds 2, a thicker portion is brought into close contact with the inner wall of the mold having a wider area, while a thinner portion is brought into close contact with the inner wall of the mold having a narrow area. As a result, the thickness of a round two- layer rice cake forming vessel formed finally is nearly uniform. |
