Deep drawing thermoplastic film components and process appts. - where film is initially stretched in eventual edge areas before thermo-forming stage produces final prod. shape

摘要

In a process for deep drawing components, e.g. container lids, in thermoplastic film the film is prestretched to a given height around the edge region of the final component. A final thermoforming stage follows to produce the final prod. shape. Process equipment comprises a tool with an upper half having a cutting plate and a lower tool half with a cutting punch and stripper plate. Upward movement of the lower tool presses the film against an elastically-loaded support in the cutting plate during the prestretching phase. The working breadth of the support is smaller than the working breadth of the cutting plate. The initial position of the support face relative to the cutting plate face depends on the component forming depth. USE/ADVANTAGE - The process is used for deep drawing thermoplastic film e.g. container lids and eliminates component thinning in the edge region thus producing a stronger prod..