Automatic packing device for pallet stacks and the procedure peculiar hereto

Claim 3

A machine for packing items comprising a frame, means on top of said frame for supplying and supporting a section of an open end flattened tubular packing hood of foil material or the like in which the margins of opposite flattened sides each comprises an outwardly projecting longitudinal fold of the hood material, means to support an item to be packed in the hood and being situated below and in alignment with the open end of the hood when the hood is supported in said supplying and supporting means, gripping elements adapted to grip and hold from outside the hood the longitudinal folds of the hood along at least one third of the lengths thereof from adjacent the open end of the hood, means to cause said gripping elements to move the gripped portions of said folds away from one another in a direction to expand said flattened hood to a form to receive said item by applying oppositely directed pulls to said gripped folds on the margins of said opposite flattened sides of the hood, means to cause relative movement of said expanded hood and said item supporting means for inserting said item into the expanded hood, said gripping elements being adapted to maintain the hood in its expanded form whereby practically the hood does not touch said item during the entire relative movement, and means to actuate said gripping elements to grip, hold and release said folds.

Claim 4

A machine for packing items comprising a frame, means on top of said frame for supplying and supporting a section of an open end flattened tubular packing hood of foil material or the like in which the margins of opposite flattened sides each comprises an outwardly projecting longitudinal fold of the hood material, means to support an item to be packed in the hood and being situated below and in alignment with the open end of the hood when the hood is supported in said supplying and supporting means, gripping elements adapted to grip and hold from outside the hood the longitudinal folds of the hood along at least one third of the lengths thereof from adjacent the open end of the hood, means to cause said gripping elements to move the gripped portions of said folds away from one another in a direction to expand said flattened hood to a form to receive said item by applying oppositely directed pulls to said gripped folds on the margins of said opposite flattened sides of the hood, means to cause relative movement of said expanded hood and said item supporting means for inserting said item into the expanded hood, said gripping elements being adapted to maintain the hood in its expanded form whereby practically the hood does not touch said item during the entire relative movement, and means to actuate said gripping elements to grip, hold and release said folds.

Claim 5

A machine as defined in claim 2 wherein each said gripping Elements comprises a movable pair of elongated gripping bars adapted to receive a longitudinally extending fold of hood material therebetween, and means for moving one bar of said pairs of bars relative to the other to grip and release a fold between said pair of bars.

Claim 6

A machine as defined in claim 3 further characterized by suction means associated with each said pair of elongated gripping bars, said suction means adapted to be engaged by longitudinally extending portions of the flattened hood adjacent said folds, and means to shift said suction means relative to said gripping bars for moving each said hood folds into gripping engagement with one of said pairs of gripping bars.

Claim 7

A machine as defined in claim 4 further characterized in that each said pair of gripping bars is pivotably suspended at the upper end thereof, and in that means are provided to swing each pair of gripping bars in such a way that the edges of said open end of the hood are tautened.

Claim 8

A machine as defined in claim 3 further characterized by means to move each pair of gripping bars outwardly in said frame above said item to be packed thereby applying said pulls to said gripped folds, and wherein said means to cause said relative movement of said expanded hood and said item consist of means to move each pair of gripping bars downwardly in said frame.

Claim 9

A machine as defined in claim 2 wherein said gripping elements consists of four series of pairs of synchronously driven rollers rotatively in engagement with each other, which series each extends in the upper part of said machine frame from said supporting and supplying means for the hood and along paths each leading to the expected position of one of four outermost upper corners of said item to be packed and at a short distance therefrom, each said series of rollers further extending downwardly adjacent to the vertical edges of said item to the bottom level of said item, each series of rollers thus forming a transfer path for one of said longitudinal folds being gripped and held between the rollers in said series, those rollers situated in said upper part of the frame providing for said pulls, and those rollers situated at the sides of said item providing for said relative movement, the rollers in each pair being movable out of mutual engagement when said hood is pulled fully over said item.

Claim 10

A machine as defined in claim 7 further characterized in that each pair of rollers rotates about axes being slightly inclined relative to a normal to the transfer path to which the pair belongs in such a way that an escape of said gripped fold from said pair of rollers is counteracted.