An Expansible Press Plunger, An Attachment Unit For Attaching A Container Element To A Container Body And A Method For Sealing A Packaging Container

An expansible press plunger, the expansible press plunger having a plunger axis extending in an axial direction perpendicular to a radial direction, the expansible press plunger being expansible in the radial direction and comprising a base plate, a first expansion tool and a second expansion tool, the first expansion tool and the second expansion tool being movable in relation to each other in the axial direction, the base plate having a bottom surface and an upper surface opposite the bottom surface, the upper surface facing the first expansion tool and the second expansion tool in the axial direction, the second expansion tool having a top end and a bottom end and comprising an expansion tool side wall having an inner surface and an outer surface, the expansion tool side wall extending from the top end to the bottom end of the second expansion tool, the expansion tool side wall comprising a circumferential edge portion at the bottom end of the second expansion tool, the circumferential edge portion of the second expansion tool being arranged outward of the first expansion tool in the radial direction, the second expansion tool being transformable between an unexpanded state and a radially expanded state, wherein the first expansion tool comprises at least one inclined plane surface, each inclined plane surface of the first expansion tool having a first end and a second end, the first end being arranged closer to the base plate than the second end in the axial direction, the at least one inclined plane surface of the first expansion tool being inclined away from the plunger axis from the first end of each inclined plane surface to the second end of each inclined plane surface, and in that the second expansion tool comprises at least one inclined plane surface, each inclined plane surface of the second expansion tool corresponding to an inclined plane surface of the first expansion tool, each inclined plane surface of the second expansion tool having a first end and a second end, the first end being arranged further away from the base plate than the second end in the axial direction, each of the inclined plane surface of the second expansion tool being inclined towards the plunger axis from the first end of the inclined plane surface to the second end of the inclined plane surface, each inclined plane surface of the first expansion tool contacting and applying pressure to the corresponding inclined plane surface of the second expansion tool when the expansible press plunger is in the radially expanded state, wherein the second expansion tool is transformable between the unexpanded state and the radially expanded state by movement of the first expansion tool downward inside of the side wall of the second expansion tool towards the base plate until the first end of each inclined plane surface of the first expansion tool meets a corresponding first end of an inclined plane surface of the second expansion tool and by a continued downward movement until the at least one inclined plane surface of the first expansion tool is fully aligned with the at least one inclined plane surface of the second expansion tool, wherein the second expansion tool is made of a material which can be repeatedly flexed and/or stretched without failing.