Method for gas filling of a compartment of a flexible container

Method for handling containers of collapsible type in a filling machine comprising consecutively arranged stations comprising a filling station and a gas filling station,

• each container comprising two flexible opposing side walls defining a product compartment communicating with the environment via a filling duct and a separate handle compartment communicating with the environment via an inlet arranged in one of the two side walls,
• the handle compartment comprising a first segment intended to form a handle, a second segment comprising the inlet in one of the side walls, and a third segment formed as a narrow duct connecting the first and second segments, the method comprising
• intermittently moving the containers to the consecutively arranged stations,
• supplying, at the filling station, liquid product into the product compartment by means of a filling tube inserted in the filling duct of the container an supplying, at the gas filling station, gas into the handle compartment, comprising
• applying a single nozzle over the inlet by relative motion of the nozzle and an abutment towards each other thereby clamping the second segment of the handle compartment with the inlet facing the single nozzle, wherein the abutment comprise a body provided with a recess which is partially enclosed by a semi-circular abutment surface defining a side opening which is aligned with the third segment of the handle compartment, and
• subsequently supplying the gas through the single nozzle,
• wherein the filling station and the gas filling station are operated such that liquid product is supplied to the product compartment of one of the containers situated at the filling station while gas is supplied to the handle compartment of another of the containers situated at the gas filling station, characterized in that the step of supplying gas at the gas filling station comprises providing a first gas flow at a first pressure and delivering said first gas flow from the single nozzle to the handle compartment via said inlet,
• subsequently providing a second gas flow at a second pressure, lower than said first pressure, and delivering said second gas flow from the single nozzle to the handle compartment via said inlet for establishing a target pressure inside said handle compartment corresponding to said second pressure;
• and
• subsequently transferring each container from the gas filling station to an output station, using a gripping member comprising an integrated sealing unit, and while providing the container with a seal entrapping gas introduced into the handle compartment.