Method and an installation for thermoforming, filling, and closing re-entrant receptacles

An installation for making, filling, and closing re-entrant receptacles presenting rims of diameter smaller than the diameter of the bodies of said receptacles, the installation comprising means for causing a strip of thermoplastic material to advance stepwise, and comprising from upstream to downstream in the stepwise advance direction of said strip:

• a thermoforming station suitable for thermoforming a transverse row of receptacles in said strip;
• a filling station for filling a row of receptacles;
• a closing station for closing a row of filled receptacles with a covering;
• and a separator station for separating a row of closed receptacles from the strip of thermoplastic material,
• the installation including, upstream from the thermoforming station, a preliminary cutting station suitable for making preliminary cuts separated by attachment points in a transverse stripe of said strip of thermoplastic material used for thermoforming a row of receptacles in a subsequent cycle, the preliminary cuts defining practically the entire final periphery of the rim of each receptacle that is to be thermoformed, and the separator station having means for breaking said attachment points in a subsequent cycle.