Vacuum packaging apparatus

A vacuum packaging apparatus for use in evacuating the air in an open-ended package and sealing the evacuated package, the apparatus comprising:

• a means defining a chamber sized only for receipt of the open end of the package with the remainder of the package disposed outside of the chamber;
• an evacuating means for evacuating the chamber and the package through the open end;
• a sealing means for sealing the open end of the bag, the sealing means including a seal bar supported for movement within the chamber between a retracted position removed from pressing engagement with the package and an extended position in pressing engagement with the package, a sealing wire supported on and extending across the seal bar, and an electrical circuit for supplying current to the sealing wire for heating the wire to a temperature sufficient to seal the package when the seal bar is in pressing engagement with the package;
• and
• a shifting means for shifting the seal bar between the retracted and extended positions, the shifting means including a bladder on which the seal bar is supported, and a means for inflating the bladder to shift the seal bar to the extended position,
• the means for inflating the bladder including a line connecting the bladder with the evacuating means and a normally open valve movable between a closed position in which the bladder is closed off from the evacuating means and an open position in which the bladder is connected to the evacuating means, the bladder being inflated in the closed position of the valve upon evacuation of the chamber.