Thermoform packaging machine with movable mold insert

A method of forming a film in a thermoform packaging machine, wherein the thermoform packaging machine comprises:

• a packaging film conveyed through the thermoform packaging machine in a transport plane;
• a forming station for forming troughs in the packaging film, said forming station having a forming tool upper part and a forming tool lower part, wherein the forming tool upper part and the forming tool lower part are disposed for relative movement between an open position and a closed position, wherein said forming tool upper part and said forming tool lower part clamp said packaging film in said closed position;
• and
• at least one mold insert having a mold bottom and at least two sidewalls, the at least one mold insert being positioned at least partially in an interior of the forming tool lower part;
• wherein the at least one mold insert has a first undercut defined in a first sidewall and a second undercut defined in a second sidewall for thermoforming said troughs in said packaging film, the first sidewall being in opposing relationship with the second sidewall, said troughs having undercut portions, wherein the at least one mold insert is movable relative to the forming tool lower part and orthogonally to the transport plane of the packaging film between a molding position and a removal position, wherein the at least one mold insert is at least moveable within said forming tool lower part from said molding position to said removal position when said forming tool upper part and said forming tool lower part are in said closed position, and
• wherein the at least one mold insert is formed as a single component,
• the method comprising the steps of:
• closing the forming station and clamping the film between the forming tool upper part and the forming tool lower part;
• moving the at least one mold insert within the forming tool lower part in a direction orthogonal to a transport plane of the film into said molding position;
• thermoforming the film into the at least one mold insert accommodated in the interior of the forming tool lower part, so as to form troughs while bringing the film into contact with the undercuts defined in the mold insert, with the mold insert occupying a forming position;
• moving the mold insert relative to the forming tool lower part and relative to the formed film from the molding position to a removal position while the film remains clamped between the forming tool upper part and the forming tool lower part;
• and
• opening the forming station after said thermoforming the film step.