Packaging machine

Claim 1

Packaging apparatus for wrapping a bundle in a heat-sealable sheet sealing material film comprising: an entrance platform for supporting a bundle to be packaged; an exit platform adapted to receive the bundle and movable horizontally toward and away from the entrance platform, and being adjacent the entrance platform when in one of its positions of rest; a framework adjustably vertically mounted with its plane lying between the entrance and exit platforms, the exit platform overlying a portion of the framework when in said one position of rest; top and bottom sealing beams carried by said framework and movable toward and away from each other, the bottom beam normally being positioned at rest below the level of the entrance and exit platforms and below the exit platform when the latter is in said one position of rest adjacent the entrance platform; means for adjustably moving said framework and said sealing beams carried thereby to a predetermined position above said platforms in order to fix the line of side sealing along the length of the bundle at a predetermined distance above the entrance platform; plural sources of continuous sheets of sealing material, one source above said platforms, and one source below said platforms; guide means for conducting the sealing material from each source to a common vertical plane between the entrance and exit platforms; first means for moving said bundle from the entrance platform to the exit platform, the bundle thereby upon being so moved carrying the plastic sheet with it; means for moving the exit platform away from the entrance platform a distance sufficient to let the bottom sealing beam move upwardly between the platforms; means for causing said bottom and top sealing beams to move toward each other to bring together said sealing material behind said bundle for side sealing the sealing material; means for heating said sealing material sheets where brought together thereby to fuse them together in a seal and sever the sealed portion along a line while leaving sealed portions on each side of said line; control means for cycling the motion of said first means, the exit platform, and the bottom and top, sealing beams whereby after said exit platform has moved from the entrance platform but before said sealing beams move toward each other, said first means is moved out of the motion path of said sealing beams; and whereby after a sealing has taken place, said sealing beams are moved apart and said exit platform returns to said one position of rest adjacent said entrance platform; and end sealing means comprising a second platform for receiving the side sealed bundle from said exit platform; a horizontally extending lower beam at a fixed distance above floor level; an upper sealing beam movable toward the lower sealing bar to engage therewith, with end sealing material being pressed therebetween; heating means for fusing the end folds together along the meeting line of said upper and lower sealing beams; means for controlling the motion of the upper sealing means; and means for automatically adjusting the height of said second platform inversely with respect to the adjustment of said framework, whereby sealing of said end sealing material occurs generally in the horizontal mid-plane of the bundle.