| 摘要 |
PURPOSE:To continuously effect a series of sealing operations with improved virgin sealing function by vacuum forming a heat shrinkable film using a heating belt in such manner as not to cause the heat shrinkage thereof and capping the lid part of a can therewith for virgin sealing. CONSTITUTION:A heat shrinkable film 1 is continuously fed into a forming process B, while being protected against heating and preheated in close contact with a heating belt 3. It is then opened facing outward around the peripheral surface of a continuously rotatable forming drum 6. The preheated film is brought into close contact with a vacuum forming die 7, the upper surface of the film is held down by the heating belt 3 and the vacuum formation is continuously effected under reduced inner pressure of the die, while the heating belt is being elastically pressed by a hold-down roller 4 from the reverse side thereof. The forming drum is then disengaged from the heating belt, and the film so formed is cut into the form of a cap. This cap-shaped film is thereafter disengaged form the die and placed over the surface to be covered with a lid of a can fed and such film is heat shrunk. |
