Prefolded cardboard blank, method and system for folding closed packaging boxes of varying height and length

1. A prefolded cardboard blank for folding closed packaging boxes of varying height and length, said blank comprising:

a bottom panel;

two side panels, each of the side panels joined to opposite edges of said bottom panel;

a first end panel joined with a first edge to said bottom panel, with a second edge to one of said side panels and with a third edge to the other one of said side panels such that the first end panel and the side panels when erected from the bottom panel form together with the bottom panel a box having an open top and an open side;

the first end panel having an end portion intended to form a first top panel, each side panel having an end portion intended to form at least one second top panel and a corner panel

the bottom panel having an end portion intended to form a second end panel and a third top panel, and

each side panel having a crease line running upwards at an angle of 45° from the bottom panel, from a corner; where the edges of the respective side panel, the first end panel and the bottom panel meet.

2. The prefolded cardboard blank according to claim 1 , wherein the prefolded cardboard blank is formed of a single piece of cardboard.

3. The prefolded cardboard blank according to claim 1 , wherein the bottom panel is formed from a first piece of cardboard and the first end panel and the side panels are formed from a second piece of cardboard.

4. The prefolded cardboard blank according to claim 1 , wherein the dimensions of the panels fulfil the following relations within material-caused tolerances: total length L B of bottom panel: L B =2 L +H, width of bottom panel: W, total length L E of first end panel L E =H +M 2 , width of first end panel: W, total lengths of side panels: L s =L +M l , width W s of side panels: W s =H +M 2 , wherein L denotes the maximum length of a desired box to be folded from the prefolded cardboard blank, H denotes the maximum height of such box, W denotes the width of such box and M 1 and M 2 denote a minimum overlap of the end portions of the panels chosen depending on the cardboard used for making the blank and the desired stability of the box to be folded.

5. The prefolded cardboard blank according to claim 4 , wherein slits of length M 2 are provided in a number of top end corners between the first end panel and the side panels and slits of length M l are provided between the free ends of the side panels and the bottom panel.

6. The prefolded cardboard blank according to claim 1 , further comprising strips of double-sided adhesive tape provided on at least some of the panels forming the first, the second and the third top panels.

7. The prefolded cardboard blank according to claim 1 , wherein the first end panel and the side panels each are provided with a number of parallel crease lines at predetermined height from the bottom panel.

8. A method for folding a closed packaging box of varying height and length using a prefolded blank, the prefolded blank including a bottom panel, two side panels, each joined to opposite edges of said bottom panel and a first end panel joined with a first edge to said bottom panel, with a second edge to one of said side panels and with a third edge to the other one of said side panels such that the first end panel and the side panels when erected from the bottom panel form together with the bottom panel a box having an open top and an open side, the first end panel having an end portion intended to form a first top panel, each side panel having an end portion intended to form at least one second top panel and a corner panel, the bottom panel having an end portion intended to form a second end panel and a third top panel, and each side panel having a crease line running upwards at an angle of 45° from the bottom panel, from a corner, where the edges of the respective side panel, the first end panel and the bottom panel meet, the method comprising:

incising the corners between the first end panel and the side panels from the open top down to a desired height of the box to be folded;

incising the side panels down from the open top to said desired height of said box to be folded at a desired length of said box;

incising the junctions between each side panel and the bottom panel from the free end of each side panel to said desired length of said box;

folding the side panels inwards at said desired length to form corner panels;

folding the free ends of said corner panels downwards at said desired height to form top panels;

folding the side panels down at said desired height to form top panels;

folding the first end panel downwards at said desired height to form a top panel and

folding the free end of the bottom panel upwards at said desired length to form a second end panel and then downwards at said desired height to form a top panel.

9. The method according to claim 8 , further comprising:

creasing the first end panel and the side panels at the desired height of the box;

creasing said side panels at the desired length of the box; and

creasing said bottom panel at the desired length and at the desired height of the box.

10. The method according to claim 8 , further comprising: shortening the bottom panel such that the length of the top panel formed from the bottom panel does not exceed the length of the desired box.

11. The method of claim 8 , further comprising:

cutting away the corner of each side panel above said desired height and beyond said desired length before folding the side panels inwards at said desired length to form corner panels.

12. The method according to claim 11 , further comprising:

creasing the first end panel and the side panels at the desired height of the box;

creasing said side panels at the desired length of the box; and

creasing said bottom panel at the desired length and at the desired height of the box.

13. The method according to claim 11 , further comprising: shortening the bottom panel such that the length of the top panel formed from the bottom panel does not exceed the length of the desired box.

14. A system to fold a closed packaging box of varying height and length using a prefolded blank, the prefolded blank including a bottom panel, two side panels, each joined to opposite edges of said bottom panel and a first end panel joined with a first edge to said bottom panel, with a second edge to one of said side panels and with a third edge to the other one of said side panels such that the first end panel and the side panels when erected from the bottom panel form together with the bottom panel a box having an open top and an open side, the first end panel having an end portion intended to form a first top panel, each side panel having an end portion intended to form at least one second top panel and a corner panel, the bottom panel having an end portion intended to form a second end panel and a third top panel, and each side panel having a crease line running upwards at an angle of 45° from the bottom panel, from a corner, where the edges of the respective side panel, the first end panel and the bottom panel meet, the system comprising:

at least one cutting station including one or more cutters that are selectively operable to:

incise the corners between the first end panel and the side panels from the open top down to a desired height of the box to be folded,

incise the side panels down from the open top to said desired height of said box to be folded at a desired length of said box,

incise the junctions between each side panel and the bottom panel from the free end of each side panel to said desired length of said box,

at least one folding station including one or more structure to:

fold the side panels inwards at said desired length to form corner panels,

fold the free ends of said corner panels downwards at said desired height to form top panels,

fold the side panels down at said desired height to form top panels,

fold the first end panel downwards at said desired height to form a top panel and

fold the free end of the bottom panel upwards at said desired length to form a second end panel and then downwards at said desired height to form a top panel.

15. The system according to claim 14 , further comprising: a sealing station to fix the top end panel formed by the end portion of the bottom panel to the top panel formed by the end portion of the first end panel.

16. The system according to claim 14 wherein the one or more cutters of the at least one cutting station is further selectively operable to:

cut away the corner of each side panel above said desired height and beyond said desired length.

17. The system according to claim 16 , further comprising: a sealing station for fixing the top end panel formed by the end portion of the bottom panel to the top panel formed by the end portion of the first end panel.