| 摘要 |
PURPOSE:To produce a foamed sheet while lowering the height of a foaming chamber and improving working efficiency, by dividing the foaming chamber into a zone wherein a thermoplastic resin sheet is formed while moving vertically upward and a zone wherein the sheet is foamed while moving vertically downward. CONSTITUTION:A blandk shert 8, horizontally introduced into a preheating chamber 1, is placed on a metallic mesh belt conveyor 4 passing between heaters 5 provided at upper and lower parts of the interior of the chamber 1, and is conveyed to th lower end of a first foaming zone 2. At this moment, the blank sheet 8 is in a state immediately before starting foaming, the moving direction thereof is changed by water-cooled guide rolls 9, 10 provided in the first forming zone 2, and the sheet 8 is introduced into a second foaming zone 3. Heaters 6, 7 are provided in the first and second foaming zones 2, 3, whereby the flank sheet 8 is formed by heating. A foamed sheet 17 obtained by completing the foaming in the second foaming zone 3 is taken up by take-up rolls 12 through a guide roll 11 provided at the lower end of the second foaming zone 3. |
