Device for sealing the bottom or lid of an ecologically designed cardboard box using an extensible bearing element

A device for sealing a lid or a bottom of a package on a package body by melting a reactivatable material using a sealing stamp allowing the bonding between one or more walls of the bottom or the lid and the body comprising:

• an elastomeric extensible bearing element with a generally polygonal shape,
• a die for shaping the bottom or the lid, intended to receive the bottom or the lid stamped using the sealing stamp;
• a counter-die, intended to receive the package body, comprising a housing receiving the extensible bearing element located across from a sealing zone of the body of the package and across from the sealing stamp;
• and
• wherein the extensible bearing element has a profile in cross-section comprising two extension sections with a parallel generally elongated shape extending along an extension direction (E),
• the extension sections each being connected, at one of their ends, to a bearing section, such that the extension sections and the bearing section define an inflation cavity of the extensible bearing element,
• the bearing section comprising a substantially flat free bearing surface, configured to come into contact with the package body, the bearing surface extending along a plane substantially normal to the extension direction (E),
• means for inflating the extensible bearing element by means of the inflation cavity that are configured to cause the extension of the extension sections, such that the extension of the extension sections causes the bearing surface to be paced in contact against the package body,
• the extension sections being configured so as to extend along the extension direction (E) during the inflation of the extensible bearing element.