Fully automatic apparatus for loading containers with single pieces assembled in sheet-wrapped stacks, such as sacks or the like

Claim 1

A fully automatic apparatus for loading containers with single pieces assembled in sheet-wrapped stacks, such as sacks or the like, said apparatus characterized by the combination of: a. a pair of devices for the compound stacking of the single pieces, each stacking device comprising an elevated feed conveyor for feeding the single pieces, a transfer bar extending parallel to the direction of movement of the feed conveyor, the transfer bar being movable perpendicularly to the conveyor feed direction, and a packing plate extending parallel to the feed conveyor and serving as a transfer member operatively associated with a lifting platform, said platform adapted to be raised or lowered, the pair of stacking devices being arranged opposite to each other and mutually connected by a pair of roller tracks, each roller track of said pair of roller tracks being associated with one stacking device of said pair of stacking devices whereby the pair of roller tracks extend at a lower elevation than the elevated feed conveyor, and a roller conveyor serving as a transfer conveyor, the rollers of which extend transversely of the rollers in said pair of roller tracks, said roller conveyor being arranged in between the inner adjacent ends of said pair of roller tracks; b. a device for packing the stacks of single pieces in synthetic sheet or respectively in heat shrinkable thermoplastic sheet, said packing device mounted downstream of said transfer conveyor and including a frame, a pair of sheeting supply drums mutually spaced one above the other and adapted to form a vertical sheet curtain extending transversely of the feed direction of the stacks, a welding and severing device on the downstream side of the sheet curtain, a discharge conveyor and welding devices mounted on opposite sides of said discharge conveyor and adapted to seal the lateral open edges of a sheet sleeve wrapped around a stack; c. a shrinkage tunnel having a separate discharge conveyor, both arranged downstream of said packing device; d. a roller conveyor having driven rollers arranged downstream of said shrinkage tunnel with said discharge conveyor, a stacking device for stacking a stack on top of another stack, said stacking device arranged adjacent said roller conveyor and comprising a frame, a lifting platform vertically movable in said frame, lifting forks on said lifting platform at the end of the platform facing the roller conveyor and adapted to be lowered between the rollers of the roller conveyor when the lifting platform is in its lowered position, and control devices arranged adjacent the stacking device in the path of movement of the stacks on the roller conveyor and adapted to be actuated by the stacks, the control devices coupled to drive means for raising and lowering the lifting platform; e. a transfer and storage conveyor arranged transversely of the roller conveyor at the discharge side of the roller conveyor, the transfer and storage conveyor comprising a pair of roller tracks arranged one bEhind the other with an intermediate spacing corresponding substantially to the width of said roller conveyor adjacent the stacking device, and transfer devices for the stacks whereby said roller tracks are mounted in carriage type frames movable by means of drive means transversely of said roller conveyor downstream of said shrinkage tunnel conveyor; f. a pair of tilting frames tiltable about their mid portions and arranged such that each tilting frame is opposite to an outer end portion of one roller track of said pair of roller tracks of said transfer and storage conveyor and extends transversely thereof, each tilting frame including a first frame section facing the transfer and storage conveyor and connected at its lower side to a lifting device, a roller track in said first section having rollers extending parallel to the rollers of said pair of roller tracks and a second frame section in the extension of the tilting frame roller tracks and which is arranged in the form of a support plate for a container; g. and whereby the drive means of the feed and discharge conveyors, of the devices for the compound stacking of the single pieces, of the stacking device for stacking a stack on top of another stack, of the movable roller tracks of the transfer and storage conveyor, of the tilting frames with the containers, of the transfer devices for transferring the stacks from the movable rollers tracks of the transfer and storage conveyor onto the roller tracks of the tilting frames, and of the roller conveyor downstream of said shrinkage tunnel conveyor are coupled to control means for controlling the various movements, and the control means are combined in a program controller.