Device and Method for Sealing Overlapping Packaging Parts

A device for the fluid-tight sealing of two partially overlapping packaging components, one being a tubular base member, formed from a blank of composite cardboard/plastics material, and an additional packaging component forming the upper packaging portion or packaging base, having at least one mandrel and one die, the mandrel having at least two expansion elements which are moved from an operating position thereof towards each other into a rest position to reduce the cross-section in order to allow ease of sliding-on of the tubular base member, the expansion elements having sealing jaws which, in the operating position thereof, form a closed circumferential outer contour, which corresponds to an inner contour formed by an opening in the die, there remaining between the inner contour and outer contour a narrow annular gap in order to apply a pressing force from an inner side to an overlap region of the packaging components and the expansion elements, each being pivotably arranged on a common base element,

• wherein
• each expansion element is secured to at least one torsion-resistant leaf spring element which enables precise pivoting of the respective expansion element between the rest position and operating position.