An apparatus may include a film support roller supporting a film roll and a housing that may include a sealing portion having an aperture sized to receive a top portion of a container. The housing may define a film path leading from the film roll to the sealing portion. A guide support assembly may have a ramp and at least one guide truss positioned along the film path. The ramp and the guide truss may guide the film across the aperture within the sealing portion, covering the aperture. The motor may advance the film along the film path. The heating element may emanate energy. The controller may cause the motor to advance the film onto the ramp and cause the heating element to emanate energy to cause the film to seal the top portion of the container.

A horn and an anvil are moved toward and away from each other by axially reciprocating a driving rod and thereby reciprocatingly rotating a forked lever in a predetermined angle range. The horn and the anvil are moved toward and pressed against each other with a predetermined force with a bag mouth b held therebetween. A sensor detects the position of a second mounting block secured to the rear end of a sliding shaft of the anvil, thereby detecting the distance between respective pressing surfaces of the horn and the anvil, i.e. the thickness m of a portion of the bag mouth held between the pressing surfaces. When the thickness m is not less than a predetermined threshold value M, a vibrator is activated to perform sealing. When the thickness m is less than the threshold value M, no sealing is performed.

In a packing method, the band divided into blocks each having a length necessary for one packing of a package object in a longitudinal direction is used, and a mark is provided at a predetermined position in each of the blocks so as to arrange a boundary portion between the blocks on a blade provided in a sealing unit when the mark is detected at a detection position provided on a band feeding path of the packing machine. By performing a position alignment process of retracting the band by the roller unit from a state of which the band is fed until when at least one of the boundary portions passes over the blade, and terminating the retracting when the mark is detected at the detection position, the boundary portion is arranged above the blade, thereby the band can always be accurately cut at the boundary portion.