| 摘要 |
PURPOSE:To permit an extremely efficient curling operation of side material by providing a heating roll, a knurling roll, a guide plate, an extruding member for extruding foam sheets successively and a cooling cylinder for receiving and cooling the foam sheet after extrusion. CONSTITUTION:A strip foam sheet A is heated by a heating roll 1, the foam sheet A2 after heating is knurled by a knurling roll 8 in such a manner as to aid in the curling operation and avoid the marked occurrence of gatherings at the curled places and the foam sheet A3 after knurling is formed into a nearly circular shape while being curled along guide plates 13. After such successive curling operations for formation into the nearly circular shape, the foam sheet A3 is forced out from the guide plates 13 by an extruding member, sent into a cooling cylinder and while being passed therethrough is cooled in the circular condition and discharged therefrom. After discharging, both the ends of the foam sheet are joined together by fusion bonding. |
