Gas Charging Method and Gas Charging Apparatus for Bag Equipped with Gas Compartment Portion

Abstract

In a method and apparatus for charging a gas into a gas compartment portion ( 6 ) of a bag ( 1 ), after a pre-heating step which is performed in stop position (IV) so that the gas compartment portion of the bag is heated by a heated gas-blowing nozzle ( 27 ), a preliminary gas injection step for injecting gas into the gas compartment portion is performed by a gas blowing nozzle ( 28 ) and a receiving member ( 29 ) in stop position (V). Then, a gas filling step is carried out in stop position (VI) by gas injection nozzles ( 23, 24 ), and the incision ( 9 ) in the gas compartment portion is sealed in stop position (VII). In the following pre-heating step, the front and rear film sheets ( 7, 8 ) of the gas compartment portion are softened, and in the preliminary gas injection step, the film sheets are separated and their adhesion is eliminated.

1 . A method for charging a bag equipped with a gas compartment portion with gas,
 wherein said method is for a bag formed integrally therein with a gas compartment portion extending in a longitudinal direction in a sealed side edge portion of the bag and having a gas inlet that is formed in a film sheet constituting the gas compartment portion and places an exterior of the bag in communication with an interior of the gas compartment portion, and said bag is conveyed along a predetermined bag conveying path,   wherein said method, while the bag is on the bag conveying path, carries out a gas filling step and subsequently a gas charging step, in which:
 in the gas filling step, a discharge outlet of a gas injection nozzle connected to a pressurized gas supply source is aligned with the gas inlet, gas is injected from the gas injection nozzle into the gas compartment portion through the gas inlet, and, while the injection is in progress, a blockage region configured in the vicinity of the gas inlet is gripped by a gas blocking gripper on both sides of the bag to block fluid communication of gas between the gas inlet and the interior of the gas compartment portion; and 
 in the gas charging step, the bag, with the blockage region being clamped by the gas blocking gripper, is pressure-held on both sides at a location of the gas inlet or at a location in the vicinity of the gas inlet with hot plates to thereby seal the gas inlet or an area in the vicinity of the gas inlet and encapsulate the gas in the gas compartment portion, and 
   wherein prior to the gas filling step, said method carries out a preliminary gas injection step that, while the bag is being on the bag conveying path, aligns a discharge outlet of another gas injection nozzle connected to a pressurized gas supply source with the gas inlet and injects gas from the other gas injection nozzle into the gas compartment portion through the gas inlet.   
     
     
         2 . A method for charging a bag equipped with a gas compartment portion with gas,
 wherein said method is for a bag formed integrally therein with a gas compartment portion extending in a longitudinal direction in a sealed side edge portion of the bag and having a gas inlet that is formed in a film sheet constituting the gas compartment portion and places an exterior of the bag in communication with an interior of the gas compartment portion, and said bag is intermittently conveyed along a predetermined bag conveying path,   wherein said method carries out a gas filling step in a predetermined stop position along the bag conveying path and subsequently a gas charging step in a downstream stop position along the bag conveying path, in which:
 in the gas filling step a discharge outlet of a gas injection nozzle connected to a pressurized gas supply source is aligned with the gas inlet, gas is injected from the gas injection nozzle into the gas compartment portion through the gas inlet, and, while the injection is in progress, a blockage region configured in the vicinity of the gas inlet is clamped by a gas blocking gripper on both sides of the bag to block fluid communication of gas between the gas inlet and the interior of the gas compartment portion; and 
 in the gas charging step, the bag, with the blockage region being clamped by the gas blocking gripper and has been conveyed to the downstream stop position, is pressure-held by hot plates on both sides at a location of the gas inlet or at a location in the vicinity of the gas inlet to thereby seal the gas inlet or an area in the vicinity of the gas inlet and encapsulate the gas in the gas compartment portion, and 
   wherein in a stop position upstream of the stop position used for the gas filling step a preliminary gas injection step is carried out, whereby a discharge outlet of another gas injection nozzle connected to a pressurized gas supply source is aligned with the gas inlet and gas is injected from the other gas injection nozzle into the gas compartment portion through the gas inlet.   
     
     
         3 . The method for charging a bag equipped with a gas compartment portion with gas according to  claim 1 , wherein a pre-heating step, during which heated gas is discharged to the gas compartment portion of the bag on the bag conveying path, is carried out before performing the preliminary gas injection step. 
     
     
         4 . The method for charging a bag equipped with a gas compartment portion with gas according to  claim 2 , wherein a pre-heating step, during which heated gas is discharged to the gas compartment portion of the bag on the bag conveying path, is carried out before performing the preliminary gas injection step. 
     
     
         5 . An apparatus for charging a bag equipped with a gas compartment portion with gas, said apparatus being for a bag integrally formed therein with a gas compartment portion extending in a longitudinal direction in a sealed side edge portion of the bag and having a gas inlet which is formed in a film sheet that constitutes the gas compartment portion and places an exterior of the bag in communication with an interior of the gas compartment portion, and said bag being intermittently conveyed along a predetermined bag conveying path and, while being conveyed, the gas compartment portion of the bag is charged with gas,
 wherein said apparatus comprises:
 a plurality of pairs of bag-conveying grippers that clamp two lateral edges of a bag equipped with a compartment portion and move the bag in an intermittent manner, so that the bag is intermittently conveyed along the bag conveying path; 
 a gas injection nozzle that is connected to a pressurized gas supply source, is provided in the vicinity of a predetermined stop position along the bag conveying path, and advances toward or retracts from the bag, so that a discharge opening at a distal thereof end is aligned with the gas inlet in the advanced position to inject gas through the gas inlet into the gas compartment portion; 
 a gas blocking gripper which is installed in conjunction with the bag-conveying grippers and moved in synchronism with the bag-conveying grippers and, while the injection of the gas by the gas injection nozzle is in progress, said gas blocking gripper clamps a blockage region, which is configured in the vicinity of the gas inlet, on both sides of the bag to block fluid communication of gas between the gas inlet and the interior of the gas compartment portion; and 
 a pair of hot plates provided in the vicinity of a stop position downstream of the gas injection nozzle along the bag conveying path, said hot plates clamping the bag on both sides in a location of the gas inlet or a location in the vicinity of the gas inlet and sealing the gas inlet or an area in the vicinity of the gas inlet, thus encapsulating the gas in the gas compartment portion; and further 
 a preliminary gas injection nozzle that is connected to a pressurized gas supply source, is provided in the vicinity of a stop position upstream of the gas injection nozzle on the bag conveying path and advances toward or retracts from the bag equipped with a gas compartment portion, so that a discharge opening at a distal end of the preliminary gas injection nozzle is aligned with the gas inlet in an advanced position thereof, and gas is injected through the gas inlet into the gas compartment portion of the bag. 
   
     
     
         6 . The apparatus for charging a bag equipped with a gas compartment portion with gas according to  claim 5 , further comprising a heated gas blowing nozzle which is provided in the vicinity of a stop position upstream of the preliminary gas injection nozzle on the bag conveying path and discharges heated gas to the gas compartment portion of the bag.