Method and mould for thermoforming and folding a plastic sheet

1. A process for producing a thermoformed part, comprising the steps of:

providing a mould comprising a lower half-mould, an upper half-mould, and an abutment surface on one of said lower half-mould and said upper-half mould;

providing a heated sheet made of thermoplastic material, on said lower half-mould;

coupling said upper half-mould to said lower half-mould in such a manner to deform said sheet, then cooling said sheet inside the mould until complete consolidation is achieved;

during said cooling, cutting the sheet along at least one edge portion thereof, said cutting operation causing a simultaneous bending of the edge portion of the sheet against said abutment surface; and

removing said upper half-mould from the lower half-mould once the consolidation of the deformed sheet has been attained;

subsequent to the cutting operation and during the cooling of the sheet inside the mould, performing a folding operation inside the mould, said folding operation comprising the steps of:

moving said abutment surface away from the edge portion of the sheet; and

mechanically bending the edge portion of the sheet to resume bending towards a support surface for supporting the sheet on one of said lower and upper half-moulds.

2. A process for producing a thermoformed part according to claim 1 , wherein the bending bends the edge portion at an angle less than 90 degrees before resuming bending.

3. A process for producing a thermoformed part according to claim 1 , wherein the folding operation creates a final bend greater than 90 degrees.