US Patent 7597776 Seal tool for film-sealing machine

A sealing tool for a sealing machine has a heat-conductive and normally heated support plate having an inner face and a heat-conductive seal plate having an outer face bearing in surface contact on the support-plate inner face. A central attachment extends between the plates across the faces at a point location and substantially prevents relative movement of the plates parallel to the faces at this point location. Outer attachments spaced outward from the central attachment press the faces together with a limited force such that the faces can slide parallel to each other at the outer attachments.