Machine for filling and closing bags of synthetic plastic material

A machine for filling and closing bags of synthetic plastic material, comprising

• lowerable filling means;
• transporting means spaced downwardly from said lowerable filling means and intermittently movable in a longitudinal direction to support and transport the bags;
• a pair of carriages mounted in a space between said transporting means and said lowerable filling means at a distance corresponding to a bag width, means for reciprocatingly moving said carriages in a horizontal plane between two end positions and synchronously with said transporting means parallel to said longitudinal direction so that the bags are arranged transverse to the movement direction of said pair of carriages;
• stations for forming opening, filling and welding;
• feeding means on said pair of carriages and having two feeding arms which are provided with gripping plates, means for moving said feeding arms in said opening station from an upper position to a central position toward each other to be inserted into a bag mouth, then to a lower position in the bag and then away from each other to spread the bag and after spreding the bag, moving said feeding arms with said gripping plates further downwardly mounted to a lower transporting position;
• and
• two pairs of grippers arranged on said pair of carriages one pair being mounted on each side of said feeding means to grip bags below their mouth edges, one of said pairs of grippers being a front pair and arranged to bring an empty bag to said opening station, the feeding arms being arranged to bring a bag from said opening station to said filling station, and the other of said pairs of grippers being a rear pair and arranged for bringing a filled bag from said filling station to said welding station, so that three bags are simultaneously transported by said pair of carriages so that during the filling of the central bag one bag is opened and the already filled bag is welded.