Method of packaging carbonated beverages in flexible containers

Claim 1

A method of packaging a carbonated beverage that comprises the steps of: passing a length of flexible plastics film in tubular form upwards over an internal former which opens the tubular film; drawing the film from the former by a gripping and sealing means inserted downwardly into the open end of the tubular film and there operated to grip and seal the tubular film against it around its circumference, and then moved away from the former; cutting the tubular film transversely to leave the length required for a container suspended on the gripping and sealing means; sealing the cut end of the tubular film to close the bottom thereof and form a container; inserting the container, still held by the gripping and sealing means, into an open-mouthed mould having a cavity corresponding in shape to, and only marginally smaller than, the container when fully inflated and inflating the container into contact with the walls of the mould by introducing carbon dioxide through the gripping and sealing means to a predetermined pressure; applying a vacuum to the walls of the mould to hold the container in contact with the walls of the mould; displacing a major part but not the whole of the carbon dixoide in the container with a carbonated beverage; and, while maintaining the vacuum to hold the container in contact with the walls of the mould, releasing the gripping and sealing means and closing the open end of the container by a gas-tight seal.

Claim 2

A method of packaging a carbonated beverage that comprises the steps of: passing a length of flexible plastics film in tubular form upwards over an internal former which opens the tubular film; drawing the film from the former by a gripping and sealing means inserted downwardly into the open end of the tubular film and there operated to grip and seal the tubular film against it around its circumference, and then moved away from the former; cutting the tubular film transversely to leave the length required for a container suspended on the gripping and sealing means; sealing the cut end of the tubular film to close the bottom thereof and form a container; inserting the container, still held by the gripping and sealing means, into an open-mouthed mould having a cavity corresponding in shape to, and only marginally smaller than, the container when fully inflated and inflating the container into contact with the walls of the mould by introducing carbon dioxide through the gripping and sealing means to a predetermined pressure; applying a vacuum to the walls of the mould to hold the container in contact with the walls of the mould; displacing a major part but not the whole of the carbon dixoide in the container with a carbonated beverage; and, while maintaining the vacuum to hold the container in contact with the walls of the mould, releasing the gripping and sealing means and closing the open end of the container by a gas-tight seal.

Claim 4

A method of packaging a carbonated beverage that comprises providing an individual, flexible, tubular plastics-film container closed in a gas-tight manner except at a filling opening, inflating the container by means of carbon dioxide supplied through said filling opening to a pressure such that the container attains substantially the size desired in the final package, filling the container by displacing a major part but less than the whole of the carbon dioxide therein with the carbonated beverage to be packed supplied through said opening, and sealing the filling opening of the container, both the filling and the sealing being carried out while at least the major part of the container is kept substantially at its final size, and relaxation of the walls thereof is prevented, by continuously maintaining a greater pressure inside the container than outside the walls thereof until sealing has been completed, the prevention of relaxation of said walls during filling and sealing enabling a full charge of beverage to be supplied to the container while leaving a gas space adjacent said filling opening whereby the seal can be made between dry plastics surfaces.

Claim 5

A method of packaging a carbonated beverage that comprises providing an individual, flexible, tubular plastics-film container closed in a gas-tight manner except at a filling opening, inflating the container by means of carbon dioxide supplied through said filling opening to a pressure such that the container attains substantially the size desired in the final package, filling the container by displacing a major part but less than the whole of the carbon dioxide therein with the carbonated beverage to be packed supplied through said opening, and sealing the filling opening of the container, both the filling and the sealing being carried out while at least the major part of the container is kept substantially at its final size, and relaxation of the walls thereof is prevented, by continuously maintaining a greater pressure inside the container than outside the walls thereof until sealing has been completed, the prevention of relaxation of said walls during filling and sealing enabling a full charge of beverage to be supplied to the container while leaving a gas space adjacent said filling opening whereby the seal can be made between dry plastics surfaces.