Side sealing device of packaging machine incorporating sealing line adjusting mechanism

A packaging machine comprising:

• a machine frame comprising rails;
• a conveyance device movable along the rails and comprising a transportation belt driven by a driving device having a rotatably driven shaft, the transportation belt being adapted to carry and move an article forward;
• and
• a side sealing device comprising:
• a film forwarding device comprising a plurality of roller pairs adapted to continuously pass an edge of a package film therebetween and drive the package film forward in synchronization with the transportation belt, a pair of meshingly engaged gears respectively coaxially coupled to one of the pair of rollers, and a first pinion gear coaxially mounted to one of the pair of gears and coupled to a second pinion gear coupled to the shaft of the driving means by a chain;
• a position adjusting device comprising a support structure attached to the conveyance device, a chassis coupled to an operating device to be selectively moved with respect to the support structure, the film forwarding device being mounted to and movable with the chassis for adjusting relative position of the film forwarding device with respect to the conveyance device, the position adjusting device including (a) a bar pivotally coupled to the film forwarding device, (b) a third pinion gear rotatably mounted to one end of the bar and engaged with the chain, and (c) a spring coupled to the bar to maintain the chain in tensioned engagement with the first, second, and third pinion gears through out the movement of the film forwarding device;
• and
• a heat sealing device comprising an actuation device mounted to the chassis, a heat sealing member attached to and selectively moved by the actuation device between a first position where the heat sealing member contacts and thus heat-seals the edge of the package film and a second position where the heat sealing member is moved away from the package film.