Tube former apparatus

A packaging apparatus including a winged tube former for forming strip tube stock into a tube on being drawn thereover, and laterally extending, spaced heat seal bars and a cutter positioned therebetween, positioned beyond said tube former, operable to produce lateral end seals converting the tube into bags, forming a top seal on one bag and a bottom seal on another bag and cutting between the seals to sever one bag from the other, in which

• said former includes a former tube having a curved upper edge tapering from an apex downwardly on opposite sides thereof,
• said former tube being of sheet metal and separated at one side along a longitudinally extending line with the lowermost edge portion extending behind the uppermost edge portion,
• a winged guide sheet, of sheet metal, secured around said tube to said curved upper edge thereof to define a crown extending outwardly therefrom at an acute angle from the side of said tube and having longer and shorter side wing portions extending around said tube and overlapping in spaced relation substantially to the side thereof with said longer wing portion extending to said tube lowermost edge portion and curved inside said shorter wing portion,
• said former tube including a supporting base on which said former tube and winged guide sheet are secured and being supported in said apparatus with said overlapping wing portions being at the side of said former tube and to the side of the tube stock strip being formed into a tube so that a strip of thin tube stock drawn over said winged guide sheet and through said former tube will be formed into an elongated tube with overlapping edges at the side of the tube and on seaming and flattening in a direction from front and back relative to said former tube will have the longitudinal seam at the side of the flattened tube with the shorter portion of the tube wall overlying the longer portion of the tube wall, and said apparatus including
• means for applying a narrow double sided adhesive strip to one edge of the strip tube stock forming said overlapping tube portion,
• a backing member positioned beyond said former tube in the path of movement of said overlapping tube portion, a pressure member cooperable with said backing member positioned to press said overlapping tube portion and adhesive strip to form a releasable side seam, and
• said heat seal bars being positioned to flatten said tube to form said lateral seals with said longitudinal seam positioned substantially at the side and the shorter edge of said tube outside the longer edge of said tube.

A method of producing packages from thin tube stock which comprises

• passing a strip of thin tube stock over a winged tube former which comprises
• a former tube having a curved upper edge tapering from an apex downwardly on opposite sides thereof,
• said former tube being of sheet metal and separated at one side along a longitudinally extending line with the lowermost edge portion extending behind the uppermost edge portion,
• a winged guide sheet, of sheet metal secured around said former tube along said curved upper edge and extending outwardly therefrom at an acute angle from the side of said tube,
• said winged guide sheet having longer and shorter end portions in spaced overlapping relation at one side of said tube and spaced apart with said longer end portion extending to said tube lowermost edge portion and curved inside said shorter end portion,
• said former tube including a supporting base on which said former tube and winged guide sheet are secured and being adapted to be supported in a tube forming apparatus with said overlapping wing portions being at the side of said former tube and to the side of the tube stock strip being formed into a tube so that a strip of tube stock drawn over said winged guide sheet and through said former tube will be formed into an elongated tube with overlapping edges at the side of the tube and on seaming and flattening in a direction from front and back relative to said former tube will have the longitudinal seam at the side of the flattened tube with the shorter portion of the tube wall overlying the longer portion of the tube wall,
• and through said former tube so that said thin tube stock forms a tube with an overlapping portion substantially to the side thereof with the shorter portion of the tube wall overlying the longer portion of the tube wall,
• applying a narrow double sided adhesive strip to one edge of said strip before passing over said former whereby said overlapping portion has said adhesive strip positioned therebetween,
• moving said overlapping tube portion between a backing member positioned beyond said former tube and a pressure member positioned to press said overlapping tube portion and adhesive strip thereagainst to form a releasable side seam,
• flattening said tube with said seam at the side and passing the flattened tube between laterally extending, spaced heat seal bars with a cutter positioned therebetween in a direction from front and back relative to said former tube,
• operating said heat seal bars and cutter to produce lateral end seals converting the tube into bags, forming a top seal on one bag and a bottom seal on another bag and cutting between the seals to sever one bag from the other.