| 摘要 |
PROBLEM TO BE SOLVED: To suppress deviation of temperature rise in the inside by more effectively displacing existing air and preventing partial overheat. SOLUTION: As a previous step of a step of heating and fusion bonding foamable raw material beads charged in a cavity 1 by high temperature steam, a step including a first soaking operation of communicating the one chamber 3 with the atmosphere and supplying steam to the other chamber 2 to transmit the steam to the cavity 1 and a second soaking operation of transmitting the steam by replacing the chamber communicating with the atmosphere with the chamber for supplying the steam to switch the steam transmitting direction to opposite direction to that of the first soaking operation is provided. |
