Bag equipped with a gas channel and a method and apparatus for packaging such a bag

Abstract

A method and apparatus for packaging a bag ( 1 ) in which a gas channel ( 5 ) where the laminated films constituting the front and back faces of the bag are not fused is formed inside a sealed part ( 2 ) of the side edge, with the lower end of the gas channel opening (through a communicating portion ( 5 b )) into the bag, and a gas inlet ( 5 a ) that allows the gas channel to communicate with the outside of the bag being formed at the upper end of the gas channel. After the bag has been filled with its filling material, a pressurized inert gas is blown from the gas inlet into the gas channel and then through the gas channel into the bag, thus replacing the air inside the bag with the inert gas. After this gas replacement, the gas inlet is sealed, and the bag mouth is also sealed.

1 . A bag equipped with a gas channel, comprising:
 a sealed part provided in a bottom edge and both side edges of a bag, the sealed part being where laminated films that constitute front and back faces of the bag are sealed,   a gas channel where the laminated films that constitute the front and back faces of the bag are not fused, the gas channel being formed in the sealed part, and a part of the gas channel opening into the bag, and   a gas inlet formed in one or both of laminated films constituting front and back faces of the gas channel, the gas inlet allowing the gas channel to communicate with outside of the bag.   
     
     
         2 . The bag equipped with a gas channel according to  claim 1 , wherein
 the gas channel is formed in the sealed part of a side edge or is formed continuously in the sealed part of the side edge and bottom edge, and   the gas inlet is formed at an upper end of the gas channel.   
     
     
         3 . The bag equipped with a gas channel according to  claim 2 , wherein
 the gas channel is formed in the sealed part of the side edge, and   a lower part of the gas channel opens into the bag.   
     
     
         4 . The bag equipped with a gas channel according to any of  claims 1  to  3 , wherein
 the bag is a finished bag in which a bag is filled with a filling material, 
 air inside of the bag is replaced with an inert gas, and 
 a bag mouth at a top edge of the bag and the gas inlet are sealed. 
 
     
     
         5 . The bag equipped with a gas channel according to  claim 4 , wherein
 a sealed part that continues intermittently along the bag mouth is formed near the sealed mouth of the bag.   
     
     
         6 . A bag packaging method, in which a pair of bag conveyance grippers clamp side edges of a bag to hang down the bag while conveying the bag along a specific conveyance path, and packaging steps comprising opening up of a bag mouth, filling of the bag with a filling material, replacing of air inside the bag with an inert gas, and sealing of the bag mouth are successively carried out during conveyance of the bag, wherein
 the bag is comprised of:
 a sealed part provided in a bottom edge and both side edges of the bag in which laminated films that constitute front and back faces of the bag are sealed, 
 a gas channel where the laminated films that constitute the front and back faces of the bag are not fused, the gas channel being formed in the sealed part, and a part of the gas channel opening into the bag, and 
 a gas inlet formed in one or both of laminated films constituting front and back faces of the gas channel, the gas inlet allowing the gas channel to communicate with outside of the bag; and 
   after the filling step of filling the bag with the filling material, a gas replacement step is performed in which an inert gas is blown through the gas inlet into the gas channel and is blown through the gas channel into the bag to replace air inside the bag with the inert gas, and then a gas inlet sealing step of sealing the gas inlet and a bag mouth sealing step of sealing the bag mouth are performed.   
     
     
         7 . The bag packaging method according to  claim 6 , wherein the gas replacement step:
 places a blowing outlet of a nozzle, which is connected to an inert gas supply source, against the gas inlet, and   blows the inert gas from the gas inlet into the gas channel.   
     
     
         8 . The bag packaging method according to  claim 7 , wherein
 a horn and an anvil of an ultrasonic sealing device are disposed on both sides of the bag equipped with the gas channel with the bag in between,   an inert gas channel is formed in the horn and/or the anvil so that one end of the gas channel is connected to the inert gas supply source and another end thereof opens to a distal end of the horn and/or the anvil, the horn and/or the anvil in which the inert gas channel is formed serving also as the nozzle, and the other end of the inert gas channel being used as the blowing outlet, and   in the gas replacement step, the inert gas is blown from the gas inlet into the gas channel by the horn and/or the anvil, and   the gas inlet sealing step is carried out by the horn and the anvil.   
     
     
         9 . The bag packaging method according to  claim 6 , wherein
 during conveyance of the bag along the conveyance path, the gas replacement step is intermittently carried out a plurality of times.   
     
     
         10 . The bag packaging method according  claim 6 , wherein
 the bag mouth is pulled taut by increasing spacing between the pair of bag conveyance grippers, either after completion of the gas replacement step or during time between before start and completion of the gas replacement step.   
     
     
         11 . The bag packaging method according to any one of  claims 6  to  10 , wherein
 an intermittent sealed part formation step of intermittently forming a sealed part along the bag mouth is performed near the bag mouth between the filling step and the gas replacement step. 
 
     
     
         12 . A bag packaging apparatus, in which a pair of bag conveyance grippers clamp side edges of a bag to hang down the bag while conveying the bag along a specific conveyance path, and packaging steps comprising opening up of a bag mouth, filling of the bag with a filling material, replacing of air inside the bag with an inert gas, and sealing of the bag mouth are successively carried out during conveyance of the bag, wherein
 the bag is comprised of:
 a sealed part provided in a bottom edge and both side edges of the bag in which laminated films that constitute front and back faces of the bag are sealed, 
 a gas channel where the laminated films that constitute the front and back faces of the bag are not fused, the gas channel being formed in the sealed part, and a part of the gas channel opening into the bag, and 
 a gas inlet formed in one or both of laminated films constituting front and back faces of the gas channel, the gas inlet allowing the gas channel to communicate with outside of the bag; and 
   the packaging apparatus is comprised of a bag mouth opening device, a material filling device, a gas replacement device, and a bag mouth sealing device, which are disposed along the conveyance path, in which
 the gas replacement device comprises a nozzle that is connected to an inert gas supply source, blows an inert gas out from a blowing outlet provided at a distal end thereof and blows the inert gas from the gas inlet into the gas channel of the bag, 
 the bag mouth sealing device comprises a pair of sealing members that clamp and seal the bag mouth from both sides of the bag, and 
 a gas inlet sealing device that seals the gas inlet of the bag after gas replacement is further disposed along the conveyance path, the gas inlet sealing device comprising a pair of sealing members that clamp and seal the gas inlet from both sides of the bag. 
   
     
     
         13 . The bag packaging apparatus according to  claim 12 , wherein
 the gas inlet is formed in both of the laminated films constituting the front and back faces of the bag, and   the gas replacement device comprises a pair of nozzles that are disposed to face each other and connected to the inert gas supply source, thus blowing the inert gas out of the blowing outlet provided at the distal end.   
     
     
         14 . The bag packaging apparatus according to  claim 12 , wherein
 the gas replacement device comprises a nozzle, which is connected to the inert gas supply source and blows the inert gas out of the blowing outlet provided at the distal end, and a receiving member, which is disposed to face the nozzle and supports the back face side of the bag.   
     
     
         15 . The bag packaging apparatus according to  claim 12 , wherein
 the bag mouth sealing device serves also as the gas inlet sealing device, and   the pair of sealing members of the bag mouth sealing device clamp and seal the bag mouth and the gas inlet from both sides of the bag.   
     
     
         16 . The bag packaging apparatus according to  claim 13 , wherein
 the bag mouth sealing device serves also as the gas inlet sealing device, and   the pair of sealing members of the bag mouth sealing device clamp and seal the bag mouth and the gas inlet from both sides of the bag.   
     
     
         17 . The bag packaging apparatus according to  claim 14 , wherein
 the bag mouth sealing device serves also as the gas inlet sealing device, and   the pair of sealing members of the bag mouth sealing device clamp and seal the bag mouth and the gas inlet from both sides of the bag.   
     
     
         18 . A bag packaging method, in which a pair of bag conveyance grippers clamp side edges of a bag to hang down the bag while conveying the bag along a specific conveyance path, and packaging steps comprising opening up of a bag mouth, filling of the bag with a filling material, replacing of air inside the bag with an inert gas, and sealing of the bag mouth are successively carried out during conveyance of the bag, wherein
 the bag is comprised of:
 a sealed part provided in a bottom edge and both side edges of the bag in which laminated films that constitute front and back faces of the bag are sealed, 
 a gas channel where the laminated films that constitute the front and back faces of the bag are not fused, the gas channel being formed in the sealed part, and a part of the gas channel opening into the bag, and 
 a gas inlet formed in one or both of laminated films constituting front and back faces of the gas channel, the gas inlet allowing the gas channel to communicate with outside of the bag; and 
   the packaging apparatus is comprised of a bag mouth opening device, a material filling device, an ultrasonic sealing device, and a bag mouth sealing device, which are disposed along the conveyance path, in which
 the ultrasonic sealing device is provided such that
 the ultrasonic sealing device is comprised of a horn and an anvil in which an inert gas channel is formed in the horn and/or the anvil so that one end of the gas channel is connected to an inert gas supply source and an other end thereof opens to a distal end of the horn and/or the anvil, 
 the other end of the inert gas channel is used as a blowing outlet of the inert gas, 
 the inert gas is blown from the gas inlet into the gas channel by the horn and/or the anvil in which the inert gas channel is formed, and 
 the gas inlet is sealed by the horn and the anvil; and 
 
 the bag mouth sealing device comprises a pair of sealing members that clamp and seal the bag mouth from both sides of the bag. 
   
     
     
         19 . The bag packaging apparatus according to any one of  claims 12 - 18 , wherein
 an intermittent sealed part formation device, which makes a sealed part formed intermittently along the bag mouth near the bag mouth, is disposed next to the material filling device along the conveyance path.