Abstract: A packaging machine comprises a deep drawing station for deep drawing containers in a film sheet and a sealing station for sealing filled containers by means of a cover sheet. For obtaining a reclosable package means are provided for forming protuberances in the edge of the packages, wherein the protuberances cooperate for reclosing the container.

Abstract: Apparatus for uniformly preheating sheet material between opposed, spaced, parallel, heated members movable relative to each other into heat-transferring engagement with the sheet material, characterized in that one of said members has a uniformly-flat, unyielding surface and the other a yieldable surface embodying a plurality of uniformly-distributed protrusions between which there are recesses.

Abstract: A packaging machine having a molding station for molding a container from a web of material using a molding die provided with a side wall, a bottom area and an edge area. A rotating cylinder or roll is arranged in at least part of the edge area to prevent damage to the web of material.

Abstract: A method of and an apparatus for producing containers from thermoplastic sheet material are disclosed. The sheet material is heated to its plastic state and clamped at its periphery. Then a moulding die is advanced substantially normally towards and against the clamped heated sheet material. The moulding die has a temperature below the temperature of the heated clamped sheet material and is provided with a projecting peripheral portion and/or a recessed central portion directed towards the sheet material. By further advancing the moulding die by a predetermined amount against the sheet material, this is deformed and shaped into the desired container. A cooling air flow is directed against the clamped heated sheet material in a region thereof adjacent to the peripheral portion of the moulding die to avoid reduced wall thickness at the edge and corner regions of the container by excessive stretching of the sheet material. Thus, stable containers of uniform wall thickness may be produced.

Abstract: The packaging machine has a molding station comprising a reciprocating molding die for shaping thermoplastic sheet material to form packaging containers. Reciprocating drive is transmitted to the molding die by first engagement means provided laterally thereon and cooperating second engagement means provided laterally of the moving path of the molding die and opposite the first engagement means. The molding die may be moved into a retracted position at one end of its moving path, and when in this retracted position, the first and second engagement means are disengaged so that the molding die and any members secured thereto may be readily removed for replacement thereof and/or of molding inserts provided in a lower part of the molding station. In a preferred embodiment, the first and second engagement means are formed by a driving chain and engagement members, respectively, the engagement members being shaped to engage the chain links.

Abstract: A packaging machine which has a station in which a thermoplastic packaging foil is heated to its thermoplastic state by contacting with the surface of a heating plate. The contacting surface of the heating plate has a plurality of raised zones adjacent to and surrounded by interconnected retracted zones which together form a venting channel for preventing the inclusion of any residual air between the foil and the contacting surface of the heating plate. The raised zones are generally convex in shape, with continuous curvature towards the retracted interconnected and surrounding zones so that, in use, the foil may be applied across its total surface on the contacting surface of the heating plate without inclusion of residual air therebetween, thus achieving uniform heating of the packaging foil and avoiding any deformation or warping thereof.

Abstract: A method of and an apparatus for producing containers from thermoplastic sheet material are disclosed. The sheet material is heated to its plastic state and clamped at its periphery. Then a moulding die is advanced substantially normally towards and against the clamped heated sheet material. The moulding die has a temperature below the temperature of the heated clamped sheet material and is provided with a projecting peripheral portion and/or a recessed central portion directed towards the sheet material. By further advancing the moulding die by a predetermined amount against the sheet material, this is deformed and shaped into the desired container. A cooling air flow is directed against the clamped heated sheet material in a region thereof adjacent to the peripheral portion of the moulding die to avoid reduced wall thickness at the edge and corner regions of the container by excessive stretching of the sheet material. Thus, stable containers of uniform wall thickness may be produced.

Abstract: A sealing device suitable for use in a vacuum packaging machine. The device is provided with a sealing tool and a resilient sealing backing cooperating with said sealing tool to seal two webs of heat-sealable packaging material therebetween when the sealing tool is moved towards the sealing backing. The sealing backing has a milled or knurled contacting surface structure comprising protrusions and/or depressions which may be pyramidal in shape, and the sealing tool has a substantially smooth or planar sealing surface. Adherence of the packaging material to the backing and to the sealing tool is avoided by cooperation of the protrusions and/or depressions with the smooth or planar surface of the sealing tool.