PACKAGING UNIT FOR PACKAGING ARTICLES INTO BOXES AND RELATIVE PACKAGING METHOD

Abstract

A packaging unit for packaging articles into boxes includes a mandrel and a folding device. The mandrel is configured to accommodate at least one of the articles and is adapted to be at least partially wrapped by a blank. The blank has an outer flap and an inner flap intended to be mutually overlapped and fixed so as to form a partially closed box. The folding device is configured to abut and fold the inner flap of the blank in the direction of the mandrel when the blank is at least partially wrapped onto the mandrel. A method for packaging articles into boxes includes arranging, abutting, and folding with the packaging unit.

Claims

1-16. (canceled)

17. A packaging unit for packaging articles into boxes, comprising: a mandrel configured to accommodate therein at least one of said articles, and configured to be at least partially wrapped by a blank, said blank having an outer flap and an inner flap configured to be mutually overlapped and fixed to form a partially closed box, and a folding device configured to abut and fold the inner flap of the blank in a direction of the mandrel when the blank is at least partially wrapped onto the mandrel.

18. The packaging unit according to claim 17, wherein said folding device comprises: at least one hitting element movable with respect to the mandrel between a first position far from the mandrel and a second position close to the mandrel such that the inner flap is folded towards the mandrel, and a driving device for moving the at least one hitting element between said first and second positions.

19. The packaging unit according to claim 18, wherein said mandrel comprises a folding edge for the inner flap of the blank and said at least one hitting element is configured to press the inner flap for at least a prevailing portion of the inner flap dimension developed along said folding edge.

20. The packaging unit according to claim 18, wherein said at least one hitting element comprises at least one plate bearing an end edge configured to press the inner flap of the blank.

21. The packaging unit according to claim 18, wherein said at least one hitting element is moved between said first and second positions by a rotation motion about a rotation axis.

22. The packaging unit according to claim 21, wherein said at least one hitting element extends radially to the rotation axis.

23. The packaging unit according to claim 21, wherein the mandrel is moved along a circular trajectory contained in a movement plane, said rotation axis being tilted with respect to said movement plane and an end edge of the at least one hitting element extending parallel to said movement plane, so that said end edge is substantially parallel to a folding edge of the mandrel in the second position.

24. The packaging unit according to claim 23, wherein the end edge of the at least one hitting element is driven to rotate about said rotation axis along a trajectory with a conical surface profile.

25. The packaging unit according to claim 18, further comprising a retaining device movably guided along at least a section of a trajectory of movement of the mandrel and configured to cooperate with the mandrel for retaining the blank wrapped on the mandrel against at least one abutment surface of the mandrel, wherein the at least one hitting element of the folding device is assembled on said retaining device.

26. The packaging unit according to claim 25, wherein: said retaining device comprises a plate-shaped head and said at least one hitting element is hinged to said plate-shaped head, and is configured to swing between said first position and said second position.

27. The packaging unit according to claim 26, wherein said at least one hitting element comprises an appendage slidably coupled to a guide driven transversely to the trajectory of movement of the mandrel, so that in a movement of the retaining device the hitting element is moved between said first position and second position.

28. A method for packaging articles into boxes, comprising: arranging a blank at least partially wrapped around a mandrel containing therein one or more of said articles, to form a partially closed box around the mandrel and such that the at least partially wrapped blank has an outer flap and an inner flap configured to be mutually overlapped and fixed to form the partially closed box, and abutting and folding by a folding device the inner flap in a direction of the mandrel by moving said folding device towards the mandrel when the blank is at least partially wrapped onto the mandrel.

29. The packaging method according to claim 28, further comprising: arranging and moving at least one hitting element of said folding device with respect to the mandrel between a first position far from the mandrel and a second position close to the mandrel for folding the inner flap of the blank in the direction of the mandrel.

30. The packaging method according to claim 29, further comprising: moving the at least one hitting element between said first position and said second position by a rotation movement driven around a rotation axis.

31. The packaging method according to claim 29, further comprising: arranging and guiding a retaining device along at least a section of a trajectory of movement of the mandrel, said retaining device being configured to cooperate with the mandrel for retaining the blank wrapped on the mandrel against at least one abutment surface of the mandrel, and assembling the at least one hitting element of the folding device on said retaining device.

32. The packaging method according to claim 31, further comprising: driving the at least one hitting element of the folding device in a swinging movement relative to the retaining device between said first position and second position.

Description

[0061] The characteristics and advantages of the present solution will best result from the detailed description of some preferred embodiments thereof, illustrated by way of non-limiting example with reference to the accompanying drawings, in which:

[0062] FIG. 1 is a partial schematic and perspective view from above of a first example of packaging unit for packaging articles into boxes made in accordance with the present invention,

[0063] FIG. 2 is a partial perspective view of a detail of the packaging unit of FIG. 1,

[0064] FIG. 3 is a further partial perspective view of the detail of FIG. 2,

[0065] FIG. 3A is a partial schematic view, in perspective, of a mandrel of the packaging unit of the previous figures,

[0066] FIG. 3B is a schematic front elevation view of a blank intended to be wrapped on the mandrel shown in FIG. 3A,

[0067] FIGS. 4 to 6 are schematic side elevation views of the detail of FIG. 3, in respective and distinct operating steps,

[0068] FIG. 7 is a partial perspective view of a second embodiment example of the packaging unit in accordance with the present invention,

[0069] FIGS. 8 to 10 are schematic perspective views of a detail of FIG. 7 shown in respective and distinct operating steps,

[0070] FIGS. 11 and 12 are further perspective views of the detail of FIG. 7. With initial reference to FIG. 1, a packaging unit made in accordance with a first embodiment example of the present invention is indicated overall with 100. The packaging unit 100 is arranged to package one or more articles 1 inside boxes 2.

[0071] The articles 1 are, in this preferred embodiment example, bags containing granular, loose or bulk food products, e.g., cereal flakes.

[0072] The packaging unit 100 comprises, in its most general components, an article feeder, a blank feeding device 4 and a folding device 5 of the blanks. The article feeder can be made in any form adapted to pick up an article 1 from an upstream work station (or from a warehouse) and deliver it to the devices of the packaging unit.

[0073] The blank feeding device 4, in turn, is configured to pick up a single blank 7 from a group of blanks stacked in a stacking zone and bring it in the packaging unit. For example, the blank feeding device 4 may comprise a plurality of gripping members assembled on a carousel rotatable about a substantially vertical axis.

[0074] The packaging unit 100 is arranged to receive each article 1 from the article feeder and form a respective box 2 around the same, starting from a blank 7 supplied by the blank feeding device 4.

[0075] For this purpose, the packaging unit 100 comprises a mandrel 10 assembled on a carousel 8, rotatable around a vertical axis, so that the mandrel is moved along a circular trajectory in an advancement direction F. The trajectory is conveniently contained in a horizontal plane.

[0076] Thereby, the mandrel 10 is driven along the circular trajectory between a receiving zone, in which the mandrel 10 receives an article 1 from the article feeder, an abutment zone, in which the mandrel 10 abuts a blank 7 supplied by the blank feeding device 4, a forming zone, in which the blank 7 is folded, being wrapped around the mandrel 10, so as to form a box 2 containing the article 1, an unloading zone, in which the box 2 containing the article 1 is delivered to the subsequent processing stations and, finally, a return zone in which the mandrel 10 is returned to the receiving zone.

[0077] In the embodiment described herein, the mandrel 10 consists of a pair of mutually separate and distinct units, both assembled on an arm radially extended from the carousel 8.

[0078] With reference to the vertical axis around which the carousel 8 rotates, the two units forming the mandrel 10, which are substantially identical to each other, are arranged facing each other in a radial direction, and along such a radial direction they are moveable with respect to each other, between an operating position, in which the two units are approached one another, and a non-operating position in which they are spaced apart from each other, so as to decompose the mandrel 10. The radial direction also identifies a direction of longitudinal development of the mandrel 10, and the advancement direction F of the mandrel 10, along the circular trajectory, is thus directed transversely, and in particular is perpendicular, to the aforementioned radial direction.

[0079] On the mandrel 10, in its configuration with the two units approached one another, there is identified a lower wall 13, defining the bottom surface on which the article 1 is deposited, as well as a pair of side walls 15 and 16, delimiting the lower wall 13 at the opposite longitudinal sides.

[0080] On each side wall 15, 16, there is also identified a lower edge 18a, which is substantially coplanar with the lower wall 13, and an upper edge 18b, spaced apart from and substantially parallel to the lower wall 13.

[0081] The pairs of lower 18a and upper 18b edges constitute the folding edges around which the blank 7 is folded for the formation of the box 2. In this embodiment example, the pairs of folding edges are configured to make the box 2 assume a parallelepiped shape with pairs of opposite side faces parallel to each other. The pair of upper edges 18b defines an upper abutment surface, which is extended parallel to the lower wall 13, for the blank 7.

[0082] Similarly, the side walls 15,16 and the bottom wall 13 define, on the corresponding outer sides of the mandrel 10, respective abutment surfaces of the folded blank being wrapped around the mandrel 10. The blank 7 is made of cardstock and is suitably shaped to form a box 2 when folded around the mandrel 10.

[0083] For this purpose, folding lines 7a are obtained in the blank 7 which divide the blank 7 into a plurality of panels intended to form, alone or in combination between them, the different faces of the box 2.

[0084] The folding lines 7a are preferably creases, and each pair of adjacent panels can be swung around a respective folding line 7a separating them.

[0085] In particular, in the blank 7 there is identified a central panel 7b which is intended to be abutted as first by the mandrel 10 in the formation of box 2, as well as two panels 7c, 7d extended from the upper side and from the lower side of the central panel 7b, respectively, and separated therefrom by respective folding lines 7a. A flap 7e is extended from the panel 7c and is intended for the partial closure of the box into the tubular shape, which, with the box formed, is parallel and opposite to the central panel 7b which is abutted as first frontally by the mandrel 10 in its advancement movement.

[0086] For the formation of the opposite bases of the box 2, from each of the panels 7b, 7c, 7d and from the flap 7e there are extended from opposite sides respective base panels which can swing with respect to the respective side panel at the crease joining them.

[0087] The tubular shape assumed by the partially closed box is obtained by joining the flap 7e with a flap 7f protruding from the panel 7d, which are brought into relative overlap and then joined together, e.g., by gluing.

[0088] The flap 7e is also referred to as outer flap in that it, when overlapped on the flap 7f, lies outside the at least partially closed box. Correspondingly, the flap 7f is also referred to as inner flap in that it, when overlapped on the flap 7e, lies between the latter and the inside of the at least partially closed box.

[0089] The folding device 5 is of the type comprising a pair of plates 21 positioned on the circular trajectory of the mandrel 10 immediately downstream of the point where the blank 7 is delivered to the packaging unit by the blank feeder device 4.

[0090] The plates 21 are parallel and opposite each other as well as mutually spaced so that the mandrel 10 can be dragged therebetween at a close distance between each of the two plates 21 and the lower and upper edges 18a, 18b of the side walls 15, 16 of the mandrel 10.

[0091] At the mouth defined between the plates 21, further folding members can be provided, intended to impact the blank, for folding the panels being wrapped on the mandrel, before the latter is brought between the plates 21.

[0092] Upon exiting the pair of plates 21, the blank 7 thus assumes a folded configuration, in partial wrapping on the mandrel 10, wherein the central panel 7b is abutted by the side wall 15 of the mandrel 10, while the upper 7c and lower 7d panels are folded against the respective upper and lower abutment surfaces of the mandrel 10. Such a shape is schematically shown in FIG. 4. Downstream of the pair of plates 21, along the trajectory of movement of the mandrel 10, it is provided that a closing member 22, assembled on the mandrel 10, cooperates with the mandrel 10 in order to fold the outer flap 7e against the side wall 16 of the mandrel 10, bringing said outer flap into overlap with the inner flap, for their gluing, for example by providing glue points, so as to make the side closure of the box wrapped around the mandrel. The glue points are distributed on the inner surface of the flap 7e at a step prior to wrapping the blank on the mandrel.

[0093] The closing member 22, for example configured in the form of a bar, is controlled in a movement with which it is lowered from above on the trajectory of the mandrel 10 to perform the folding of the outer flap 7e, following the mandrel 10 in its advancement. This folding step is carried out in a section of the trajectory of the mandrel 10, extended downstream of the folding device 5, with respect to the advancement direction F of the mandrel 10.

[0094] In this section of trajectory there is provided a fixed retaining device, for example made in the form of a plate, on which a plane 11 is located intended to retain the lower panel 7d of the blank in abutment contact against the mandrel, during the advancement of the latter.

[0095] The packaging unit further comprises a folding device 30 configured to abut and fold the inner flap 7f of the blank 7 when the blank is wrapped on the mandrel, said abutment and folding actions being performed, following the mandrel in its advancement, along the trajectory section of the mandrel extended downstream of the folding device 5.

[0096] The folding device 30 comprises a pair of hitting elements 31, each hitting element including a respective plate 32 bearing a respective end edge 33 intended to press the inner flap 7f of the blank.

[0097] The plates 32 are assembled, spaced apart and in a coplanar configuration, on a shaft 34 driven to rotate about a rotation axis X. Said plates extend radially from the axis X and are axially spaced from each other at a central portion of the shaft 34 in which the shaft is coupled to a motion transmission system housed in a transmission box 35. A driving device including a motor 36 is provided for transmitting, through the transmission system, the rotation motion to the plates 32 about the axis X.

[0098] The retention plane 11 extends interposed between the pair of elements 31, as clearly shown in FIG. 2, such a configuration advantageously ensuring a continuous retention of the blank, and in particular of its lower panel, in abutment against the mandrel.

[0099] The provision of realizing the folding device 30 with the plates side by side, positioning the transmission system between the plates themselves, also allows to advantageously avoid overall encumbrances protruding laterally to the opposite axial ends of the shaft. Alternatively, in an embodiment variant, it may be provided that the folding device comprises a single hitting element, for example including a single plate with a respective end edge intended to press the inner flap of the blank, this configuration requiring the positioning of the transmission system at one of the axial ends of the shaft.

[0100] 37 indicates a superficial lowering of the plate 32 extended along the end edge 33, and such as to give the plate a tapered shape with a slight concavity that is facing the inner flap of the blank during the operating functioning of the folding device. Thanks to this shape, the impact action of the folding device against the inner flap is made more effective, at the same time optimizing the width of the angular stroke in which the inner flap is abutted and folded by the folding device.

[0101] In the rotation about the axis X, the hitting elements 31 are driven, in a movement relative to the mandrel 10 advancing along its trajectory, between a position far from the mandrel and a position close to the mandrel, in which the hitting elements 31 reach the inner flange 7f by pressing said flap being folded towards the mandrel.

[0102] FIGS. 4 to 6 show a sequence of three significant positions assumed by the hitting elements 31 of the folding device in cooperation with the mandrel 10 and with the closing member 22.

[0103] FIG. 4 shows a position in which the closing member 22 and the folding device 30 are driven towards to the mandrel.

[0104] FIG. 5 shows a position in which the closing member 22 reaches and presses the outer flap 7e being folded towards the mandrel and the hitting elements 31 of the folding device reach and press the inner flap 7f being folded towards the mandrel. In the position of FIG. 5 the plates 32 of the folding device, in their rotation motion with the direction indicated in the figure, are substantially parallel to the side wall 16 of the mandrel, so that the inner flap 7f is folded substantially at 90 around the corresponding lower folding edge 18a of the mandrel, near the wall 16 of the mandrel. In this position the hitting elements 31 are interposed between the outer flap 7e, which continues to be pressed and folded by the closing member, and the inner flap 7f, without however, during movement, there being any contact between the outer flap 7f and the hitting elements 31.

[0105] In a subsequent position of the rotation, shown in FIG. 6, the hitting elements 31 of the folder are moved away from the inner flap, allowing the outer flap, pressed by the closing member, to impact the inner flap. In this position the inner and outer flaps are brought into relative overlap and pressed against each other by the pressure exerted by the closing member 22 as well as abutted by the side wall 16 of the mandrel.

[0106] The relative positioning and the timing of the movements of the mandrel 10, of the closing member 22 and of the hitting elements 31 of the folding device are configured so that it is ensured that the outer flap, at the moment of the impact with the inner flap comes into contact with the inner flap folded substantially at 90, near the wall 16 of the mandrel, so as to ensure that the inner and outer flaps can correctly overlap each other to cause a precise gluing thereof. The profiles of the end edges 33 of the plates 32 have, in the axial direction, an extension such as to press, together, the inner flap 7f for a prevailing portion of its dimension developed along the lower folding edge 18a of the mandrel around which the inner flap is folded. In this way it is ensured that the inner flap can be effectively yielded along a prevailing portion of the respective folding line.

[0107] As shown in FIG. 3, the rotation axis X is tilted by an angle A (measured in a vertical plane containing the axis X) with respect to a horizontal movement plane of the mandrel, which contains the circular trajectory thereof.

[0108] Furthermore, the end edges 33 of the plates 32 are configured to extend substantially parallel to the folding edges of the mandrel when the folding device abuts the inner flap 7f (FIG. 6). This configuration causes the end edges 33 of the plates 32 to be driven, in the rotation about the axis X, along a trajectory with a conical surface profile, such a trajectory allowing the end edges 33 to impact the inner flap while remaining substantially parallel to the corresponding folding edge of the mandrel moving along a circular trajectory. It follows that the inner flap is impacted by the edges of the plates with a pressure distributed substantially uniformly along the surface development of the inner flap.

[0109] The angle A of inclination is linked to some geometric magnitudes of the mandrel and the trajectory thereof, in particular it is related to the pitch diameter of the circular trajectory of the mandrel and to the dimension of the blank wrapped on it, measured in the radial direction.

[0110] The order of magnitude of the angle A of inclination is some degrees and in the example described herein is preferably chosen equal to 4.5. It should be noted that the angle of inclination would be equal to 0 if the mandrel were moved along a straight trajectory.

[0111] It is also envisaged that the folding device 30 can be set in position, both in translation with respect to the movement plane of the mandrel, and angularly in order to anticipate or delay the step of folding the inner flap, in combination with the movement of the closing member. These adjustments, together with a possible retiming of the movement, are also suitable for the management of the format changes of the blanks fed to the packaging unit.

[0112] With reference to FIGS. 7 to 12, a second example of packaging unit made in accordance with the invention is described below, in which details common to those of the previous example are marked by the same reference numerals, while embodiment variants of details of the previous example are marked by the same reference numerals quoted with the addition of the graphic sign .

[0113] In this example it is provided that the hitting element 31 of a folding device 30 is assembled on a retaining device of the blank, overall indicated with 40, arranged downstream of the folding device 5.

[0114] The retaining device 40 is movably guided along a section of the trajectory of movement of the mandrel and is configured to cooperate with the mandrel 10 in order to retain the opposite upper and lower panels 7c, 7d of the blank against the respective abutment surfaces of the mandrel, in the advancement movement of the mandrel along the trajectory, and in particular during the step of closing the box made by the closing member 22.

[0115] A second retaining device 41 is arranged downstream of the first retaining device 40 at a position spaced from the folding device 5 along the trajectory of the mandrel, and the retaining device 40 is therefore movable between the folding device 5 and the second retaining device 41.

[0116] The second retaining device 41 is made with a pair of parallel and opposite plates 42 mutually spaced so that the mandrel 10, in its advancement movement, can be driven therebetween at a close distance between each of the two plates and the lower and upper edges 18a, 18b of the side walls 15, 16 of the mandrel 10.

[0117] In greater detail, the first retaining device 40 comprises a pair of opposite arms 43, parallel and spaced apart, each arm being assembled, in a movably guided manner, on the respective plate 42, so as to be moved along the trajectory section between a first position, in which it is near the corresponding plate 42 and a second position in which it is moved to a position far from the corresponding plate 42. The movements of the arms 43 take place in respective horizontal planes parallel to each other as well as parallel to the plane containing the trajectory of movement of the mandrel 10.

[0118] The arms 43 are controlled in a synchronous movement, along a first stroke extended from the first to the second position, in a direction towards the mandrel 10, which is continued in a second return stroke, in the opposite direction, in which the arms 43 are driven accompanying the mandrel, in the same advancement direction and preferably with the same speed as the mandrel.

[0119] The distance between the arms 43 is chosen so that the mandrel 10, in its advancement movement, can slide therebetween at a close distance between each arm 43 and the folding edges of the mandrel 10 facing it.

[0120] Each arm 43 is provided with a plate-shaped end head 44 capable of retaining, in the accompanying movement of the mandrel, the corresponding panel of the blank in contact against the corresponding abutment surface of the mandrel. In other words, the head 44 overlying the mandrel 10, also referred to as the upper head, retains the upper panel 7c of the blank against the corresponding upper abutment surface of the mandrel and the other head 44 underlying the mandrel, also referred to as the lower head, retains the lower panel 7d of the blank against the corresponding lower abutment surface of the mandrel. Each head 44 has a substantially T shape, in which the enlarged portion extends along a prevailing portion of the longitudinal dimension of the panels in the contact zone with the blank 7 and developed along the folding edges.

[0121] Each arm 43 is driven in its movement along the trajectory section by means of a respective driving device, indicated with 45, by means of which the corresponding arm 43 is driven in an oriented manner along the trajectory section. In an embodiment example, the driving device may comprise a mechanism for transmitting the motion of each arm 43 of the rack-pinion type, wherein a rack integrally connected to the arm 43 is coupled to a pinion that is driven to rotate by a drive member.

[0122] With reference to the folding device 30, the hitting element 31 comprises a plate 32 bearing an end edge 33 intended to press the inner flap 7f of the blank.

[0123] The plate 32 is hinged to the lower head 44, by means of a U-shaped bracket 46, the free ends 46a,b of which are connected to the plate 32. On parts opposite to said free ends, the bracket is rotatably supported on the lower head by means of a pair of coaxial hinges that identify a swing axis Y of the plate 32.

[0124] A cylindrical-shaped appendage 47 is assembled on the bracket 46 and which is slidably coupled in a seat 48 of a guide 49, so that the plate 32, moving solidly with the retaining device 40 is at the same time driven in an oscillatory movement with respect to the lower head 44, imposed by the movement of the guide 49.

[0125] For this purpose, the guide 49 is driven in an alternating movement, directed transversely to the trajectory of the mandrel, by means of a kinematic system of levers 50, coupled to the guide and driven by a motor 51.

[0126] In the swinging movement around the axis Y, the plate 32 is moved between a position close to the lower head, in which the plate is brought near the head to abut and fold the inner flap of the blank wrapped on the mandrel, and a position away from the head.

[0127] FIGS. 8 to 10 show a sequence of three significant positions assumed by the hitting element 31 of the folding device 30 in cooperation with the mandrel 10 and with the closing member 22.

[0128] FIG. 8 shows a position in which the closing member 22 and the folding device 30 are driven towards to the mandrel 10, which is advancing along its trajectory accompanied by the retaining device 40, whose heads 44 abut the blank against the mandrel. In this position the inner 7f and outer 7e flaps have not yet come into contact, respectively with the hitting element 31 of the folding device 30 and with the bar of the closing member 22.

[0129] FIG. 9 shows a subsequent position in which the closing member 22 reaches and presses the outer flap 7e being folded towards the mandrel and the hitting element 31 of the folding device reaches and presses the inner flap 7f being folded towards the mandrel. In the position of FIG. 9 the plate 32 of the folding device, in the swinging movement with respect to the lower head 44, is moving itself substantially parallel to the side wall 16 of the mandrel, so that the inner flap is folded substantially at 90 around the corresponding lower folding edge 18a of the mandrel. In this position the hitting element 31 is interposed between the outer flap, which continues to be pressed and folded by the closing member, and the inner flap, without however, during this combined movement, there being any contact between the outer flap 7e and the hitting element 31.

[0130] In a subsequent position, shown in FIG. 10, the hitting element 31 of the folder is swung away from the lower head 44, allowing the outer flap 7e, pressed by the closing member 22, to impact the inner flap 7f. In this position the inner and outer flaps are in relative overlap and pressed against each other by the pressure exerted by the closing member 22 as well as abutted by the side wall 16 of the mandrel. In this step, gluing takes place between the inner and outer flaps to complete the partial closure of the box.

[0131] It should be observed that in the position illustrated in FIG. 10 the arms 43 have concluded the return stroke, ending the accompanying action of the mandrel. The latter, continuing in the advancement along its trajectory, is brought between the plates 42, to be delivered to an unloading station in which the box, the side closure having been completed, is extracted from the mandrel 10, and the mandrel is brought back in the loading zone.