Bag Filling And Packaging Method And Bag Filling And Packaging Apparatus

Abstract

A bag mouth correcting device is disposed between a deaeration station and a sealing station. The correcting device has a pair of bar-shaped guide members. The guide members extend in the direction of movement of a bag, and an expected sealing area of the bag passes between the guide members. The guide members are disposed at a height position corresponding to the expected sealing area. The guide members extend gradually upward and the space therebetween gradually decreases as the distance from the upstream side increases toward the downstream side in the direction of movement of the bag. While passing between the guide members, the tilted bag mouth is corrected to a substantially uncurled state.

What is claimed is: 
     
         1 . A bag filling and packaging apparatus in which a bag is held, with its bag mouth facing upward, by being gripped at laterally opposite side edges thereof with a pair of laterally spaced grippers, and the bag held in this way is moved along a predetermined planar path to sequentially undergo predetermined packaging processes, the bag filling and packaging apparatus comprising:
 a steam-replacement deaeration device provided at a deaeration station and having a nozzle to be inserted into a bag filled with an article to be packaged to inject steam into the bag to replace air in the bag with the steam, thereby effecting deaeration;   a sealing device provided at a sealing station to seal an expected sealing area set at a bag mouth of the bag with a pair of hot plates; and   a guide device provided between the deaeration station and the sealing station, the guide device having a pair of guide members provided facing each other across a predetermined space at opposite sides of the bag passing therebetween and at a height position corresponding to the expected sealing area of the bag.   
     
     
         2 . A bag filling and packaging apparatus according to  claim 1 , said guide members extend over a predetermined length range in a direction of movement of the bag at a height position corresponding to the expected sealing area of the bag, and the guide members extend gradually upward and gradually coming closer to each other as a distance from an upstream side increases toward a downstream side in the direction of movement of the bag. 
     
     
         3 . A bag filling and packaging apparatus according to  claim 1 , said guide members are a pair of guide rollers. 
     
     
         4 . A bag filling and packaging apparatus in which a bag is held, with its bag mouth facing upward, by being gripped at laterally opposite side edges thereof with a pair of laterally spaced grippers, and the bag held in this way is moved along a predetermined planar path to sequentially undergo predetermined packaging processes, the bag filling and packaging apparatus comprising:
 a steam-replacement deaeration device provided at a deaeration station and having a nozzle to be inserted into a bag filled with an article to be packaged to inject steam into the bag to replace air in the bag with the steam, thereby effecting deaeration; and   a sealing device provided at a sealing station to seal an expected sealing area set at a bag mouth of the bag with a pair of hot plates;   the steam-replacement deaeration device further having a pair of pressing members provided at opposite sides, respectively, of the bag and at a height position corresponding to the expected sealing area, the pressing members being movable between respective pressing positions where the pressing members move toward each other to press the nozzle therebetween through the bag and respective retract positions where the pressing members are away from the nozzle.   
     
     
         5 . A bag filling and packaging apparatus in which a bag is held, with its bag mouth facing upward, by being gripped at laterally opposite side edges thereof with a pair of laterally spaced grippers, and the bag held in this way is moved along a predetermined planar path to sequentially undergo predetermined packaging processes, the bag filling and packaging apparatus comprising:
 a steam-replacement deaeration device provided at a deaeration station and having a nozzle to be inserted into a bag filled with an article to be packaged to inject steam into the bag to replace air in the bag with the steam, thereby effecting deaeration; and   a sealing device provided at a sealing station to seal an expected sealing area set at a bag mouth of the bag with a pair of hot plates;   the steam-replacement deaeration device further having a pair of partially sealing members provided at opposite sides, respectively, of the bag and at a height position corresponding to the expected sealing area, the partially sealing members being configured to move toward each other to partially seal the expected sealing area of the bag at laterally opposite sides of the nozzle.   
     
     
         6 . A bag filling and packaging apparatus in which a bag is held, with its bag mouth facing upward, by being gripped at laterally opposite side edges thereof with a pair of laterally spaced grippers, and the bag held in this way is moved along a predetermined planar path to sequentially undergo predetermined packaging processes, the bag filling and packaging apparatus comprising:
 a steam-replacement deaeration device provided at a deaeration station and having a nozzle to be inserted into a bag filled with an article to be packaged to inject steam into the bag to replace air in the bag with the steam, thereby effecting deaeration;   a sealing device provided at a sealing station to seal an expected sealing area set at a bag mouth of the bag with a pair of hot plates; and   a bag mouth cooling device provided between the deaeration station and the sealing station;   the bag mouth cooling device having a pair of cooling members disposed at opposite sides, respectively, of the bag passing therebetween and each having a gas outlet port, and a cooling gas supply source supplying a cooling gas to the cooling members through supply piping.   
     
     
         7 . A bag filling and packaging apparatus in which a bag is held, with its bag mouth facing upward, by being gripped at laterally opposite side edges thereof with a pair of laterally spaced grippers, and the bag held in this way is moved along a predetermined planar path to sequentially undergo predetermined packaging processes, the bag filling and packaging apparatus comprising:
 a steam-replacement deaeration device provided at a deaeration station and having a nozzle to be inserted into a bag filled with an article to be packaged to inject steam into the bag to replace air in the bag with the steam, thereby effecting deaeration; and   a sealing device provided at a sealing station to seal an expected sealing area set at a bag mouth of the bag with a pair of hot plates;   wherein, when sealing the expected sealing area of the bag, the hot plates of the sealing device respectively disposed at the opposite sides of the bag and placed at respective standby positions which are each apart from the bag by a predetermined standby distance are moved toward each other to respective restricting positions where the hot plates are each apart from the bag by a restricted distance shorter than the standby distance and where upper edges of respective abutment surfaces of the hot plates are below at least an upper edge of the expected sealing area of the bag, and after the hot plates have reached the restricting positions, at least one of the pair of hot plates and the pair of grippers is moved vertically relative to the other of the pair of hot plates and the pair of grippers to a position where the abutment surfaces of the hot plates face a whole of the expected sealing area, and the hot plates are further moved toward each other to respective sealing positions where the hot plates press the bag therebetween.