Continuously rotary thermo-forming systems and apparatus of the pressure assist, plug assist and match mold type

The method of transforming an extruded thermoplastic web having heat of extrusion retained therein and being in a thermoformable state, comprising;

• receiving said web on the peripheral surface of a rotating mold wheel having mold cavities defined in the said peripheral surface;
• providing draw assisting devices moving continuously along a conformally arcuate path with and adjacent to the periphery of said mold wheel in registry with said mold cavities over a predetermined arc of registration, said draw assisting devices also being reciprocated axially into and from said mold cavities to impart a draw assisting force;
• constraining said draw assisting devices to impart a draw assisting external force to said discrete areas of said web over said predetermined arc of registration;
• removing said draw assisting external force from said web;
• and
• thereafter removing said web and said thermoformed products from said mold wheel and said die cavities, respectively.

The method of thermoforming a thermoplastic web presented in a thermoformable state, comprising:

• receiving said web on the peripheral surface of a rotating mold wheel having mold cavities defined in the said peripheral surface;
• applying a vacuum to said web from within said mold cavities to impart a drawing force to said web tending to ingest discrete areas thereof into said mold cavities;
• providing draw assisting devices moving continuously along a conformally arcuate path with and adjacent to the periphery of said mold wheel in registry with said mold cavities over a predetermined arc of registration, said assisting devices also being reciprocated axially into and from said mold cavities to impart said drawing assisting force;
• constraining said draw assisting devices to impart a draw assisting external force to said discrete areas of said web over said perdetermined arc or registration in conjunction with and in enhancement of said drawing force imparted by the said application of vacuum internally thereof;
• removing said draw assisting external force from said web;
• subsequently removing said drawing force from said web;
• and
• thereafter removing said web and said thermoformed products from said mold wheel and said die cavities, respectively.