Dosing unit, a dosing method, and a machine for producing unit dose articles

A machine for producing unit dose articles, comprising:

• a movable surface having a plurality of cavities, continuously movable in a machine direction,
• a first feeding assembly configured for feeding a first continuous water-soluble film on said movable surface at a first position,
• a retaining system configured for retaining said first continuous water-soluble film adherent to said cavities as it moves in said machine direction,
• a dosing unit located downstream of said first position and configured for dispensing dosed quantities of at least one fluid composition into said cavities,
• a second feeding assembly configured for feeding a second continuous water-soluble film on said movable surface at a second position located downstream of said dosing unit so as to enclose said dosed quantities of at least one fluid composition between said first and second continuous water-soluble films, and
• a wetting unit configured for wetting a surface of said second continuous water-soluble film upstream of said second position,
• wherein said dosing unit comprises:
• a stationary guide defining a closed-loop guide path having a lower section and an upper section,
• a plurality of movable elements movable along said stationary guide,
• a transmission system configured for continuously moving said plurality of movable elements along said closed-loop guide path,
• a plurality of nozzles carried by respective movable elements and connected to fluid delivery lines,
• a rotary fluid distributor comprising at least one stationary inlet connected to at least one pump and a plurality of movable outlets connected to respective fluid delivery lines,
• a plurality of controlled valves associated to respective actuators and arranged for selectively opening and closing a passage of fluid through said fluid delivery lines, and
• a control unit configured for controlling an open/closed state of said plurality of controlled valves through said actuators.

A method for dosing fluid products, comprising:

• continuously moving a plurality of movable elements along a closed-loop guide path having a lower section and an upper section,
• providing on said plurality of movable elements a plurality of nozzles associated to fluid delivery lines,
• feeding at least one fluid composition to said fluid delivery lines through a rotary fluid distributor comprising at least one stationary inlet and a plurality of movable outlets connected to respective fluid delivery lines, and
• selectively opening and closing a passage of fluid through said fluid delivery lines by a plurality of controlled valves associated to respective actuators.