| 摘要 |
1. Mandrel forming device for plain or perforated synthetic resin films, for avoiding crinkling of the products thus obtained by suppressing, when the mandrel is removed, the adherence to the bottom of the mandrel of the products thus obtained, characterized by the combination of a spacing and detaching piston (10) placed at the base of the mandrel in a cavity (7, 9), a spring (8) placed in the cavity and acting on the spacing and detaching piston placed at the base of the mandrel (1) and a duct (6) for communicating the bottom (16) of said mandrel with the free air. |
