Longitudinal seam sealer for continuous motion form, fill and seal machine

A form, fill and seal machine, for forming a tube out of a heat sealable sheet, of the type including a longitudinal seam sealer for forming a longitudinal seam along lapped edge surfaces of said heat sealable sheet during movement of the sheet and a pair of cyclically movable jaw assemblies arranged on opposite sides of said tube that follow the movement of the tube during the sealing operation, each of said cyclically movable jaw assemblies having a right and a left side, the improvement wherein;

• said longitudinal seam sealer comprises:
• a pair of sealer bars each of which includes a shaped confronting portion, each sealer bar including an electric heat producing element that will when energized heat said shaped confronting portions to a temperature that will cause a seam to be formed between said lapped edge surfaces of the heat sealable sheet;
• separate mounting mechanisms for each sealer bar that permit said shaped confronting portions to move toward and away from each other;
• stop means preventing said shaped confronting portions from contacting each other and thus creating an unacceptable drag on said sheet of material;
• a first pressure roller mounted on one of said separate mounting mechanisms at a location beyond the exit end of said shaped confronting portions said first pressure roller engaging an outer surface of the lapped edge surfaces of the sheet of material along which a seam has been formed;
• a second pressure roller mounted on the other of said separate mounting mechanisms at a location beyond the exit end of said shaped confronting portions, said second pressure roller being mounted for movement on said other of said separate mounting mechanisms such that it can move toward and away from said first pressure roller, a mechanism for applying a resilient force on said second pressure roller causing it to be biased toward said first pressure roller, such that a force is applied to the seam that has been formed in the lapped edges of the heat sealable sheet;
• and
• said pair of cyclically movable jaw assemblies comprise:
• each cyclically movable jaw assembly includes right and left pairs of spaced, synchronously driven, rotary drive members;
• each cyclically movable jaw assembly includes a right and a left link base, such that said right and left pairs of spaced rotary drive members each has a corresponding link base;
• each drive member having a crank arm secured at one end thereto and pivotally connected to the corresponding link base at its other end, such that said link bases are driven in rotary paths;
• each cyclically movable jaw assembly includes a right and left pair of parallel links, arranged such that each of said right and left link bases has a corresponding pair of parallel links, each of said parallel links having first and second ends;
• pivot connections at said first end of each parallel link connecting said parallel link to the corresponding link base;
• pivot connections at said second end of each parallel link connecting said parallel link to the corresponding side of the corresponding cyclically movable jaw assembly;
• said pivot connections include pressure devices;
• said link bases, parallel links and pivot connections including said pressure devices function to bias said pair of cyclically movable jaw assemblies toward each other in arcuate paths while maintaining one jaw assembly parallel with respect to the other jaw assembly.

A form fill and seal machine for packaging product in a tube type bag formed from a continuous film comprising:

• a longitudinal seam sealer for continuously forming a longitudinal seam along lapped edge surfaces of said continuous film comprising:
• a pair of sealer bars each of which includes a shaped confronting portion, each sealer bar including an electric heat producing element that will when energized heat said shaped confronting portions to a temperature that will cause a seam to be formed between said lapped edge surfaces of the sheet material passing there between continuous film passing there between;
• separate mounting mechanisms for each sealer bar that permit said shaped confronting portions to move toward and away from each other;
• stop means preventing said shaped confronting portions from contacting each other and thus creating an unacceptable drag on said sheet of material;
• a first pressure roller mounted on one of said separate mounting mechanisms at a location beyond the exit end of said shaped confronting portions at which the edges of the sheet of material along which a seam has been formed;
• a second pressure roller mounted on the other of said separate mounting mechanisms at a location beyond the exit end of said shaped confronting portions, said second pressure roller engaging the other outer surface of the lapped edges of the continuous film along which a seam has been formed, said second pressure roller being mounted for movement on said other of said separate mounting mechanisms such that it can move toward and away from said first pressure roller, a mechanism for applying a resilient force on said second pressure roller causing it to be biased toward said first pressure roller, such that a force is applied to the seam that has been formed in the lapped edges of the continuous film;
• link bases;
• a drive for driving said link bases through continuous cycles such that they have a longitudinal component of movement along said tube;
• sealing jaw assemblies mounted on said link bases for movement toward and away from each other;
• pressure devices mounted on said link bases and said sealing jaw assemblies exerting pressure on said sealing jaw assemblies forcing them toward each other;
• said pressure devices allowing movement of said sealing jaw assemblies toward each other to cease upon contact, while permitting movement of said sealing jaw assemblies along said tube;
• a programmable processor for controlling the speed of said drive during increments of said cycle to control the bag size and sealing time.

A form, fill and seal machine, for forming a tube out of a heat sealable sheet, of the type including a longitudinal seam sealer for continuously forming a longitudinal seam along lapped edge surfaces of said heat sealable sheet and first and second cyclically movable jaw assemblies arranged on opposite sides of said tube that follow the movement of the tube during the sealing operation and wherein said longitudinal seam sealer comprises:

• a pair of sealer bars each of which includes a shaped confronting portion, each sealer bar including an electric heat producing element that will when energized heat said shaped confronting portions to a temperature that will cause a seam to be formed between said lapped edge surfaces of the heat sealable sheet passing there between;
• separate mounting mechanisms for each sealer bar that permit said shaped confronting portions to move toward and away from each other;
• stop means preventing said shaped confronting portions from contacting each other and thus creating an unacceptable drag on said sheet of material;
• a first pressure roller mounted on one of said separate mounting mechanisms at a location beyond the exit end of said shaped confronting portions, said first pressure roller engaging an outer surface of the lapped edges of the heat sealable sheet along which a seam has been formed;
• a second pressure roller mounted on the other of said separate mounting mechanisms at a location beyond the exit end of said shaped confronting portions, said second pressure roller engaging the other outer surface of the lapped edges of the heat sealable sheet along which a seam has been formed, said second pressure roller being mounted for movement on said other of said separate mounting mechanisms such that it can move toward and away from said first pressure roller, a mechanism for applying a resilient force on said second pressure roller causing it to be biased toward said first pressure roller, such that a force is applied to the seam that has been formed in the lapped edges of the heat sealable sheet;
• and
• wherein a drive for each side of said jaw assemblies comprises:
• a gear case located on one side of the tube;
• an input drive shaft for said gear case;
• a driver gear journaled in said gear case and carried by said input drive shaft;
• a first and second set of spaced output shafts drivingly connected to said first and second cyclically movable jaw assemblies respectively;
• first drive gears, journaled in said gear case and secured to said first set of spaced output shafts, said first drive gears each being driven, in the same direction, by said driver gear that is carried by said input drive shaft;
• second drive gears, journaled in said gear case and secured to said second set of spaced output shafts, each of said second drive gears being driven, in the same direction from and by one of said first drive gears.