PACKER

Technical Field

The invention relates to a cardboard packer, in particular to a cardboard packer for producing boxes, trays, and/or wrap-around units for a plurality of carton packages. The invention also relates to a folding unit for such cardboard packer, as well as to a folding method for a cardboard packer.

Background Art

Individual packaging containers, such as liquid food packaging containers, are typically produced from a carton-based material and filled using a high-speed filling machine. When the filled, formed, and sealed packaging containers are unloaded from the filling machine they are transferred to a cardboard packer in which a predetermined number of packaging containers are stacked in a packing pattern and placed in a case made from a cardboard blank.

The cardboard case, which may be in the form of a box, a tray, or a wrap- around unit is produced by folding the blank; the blank may e.g. be formed by cutting a corrugated cardboard sheet or the like into a predetermined shape. The shape of the blank varies in accordance with the dimension and number of packaging containers to be placed in the case, and the manner of packaging. In the case of a tray blank, the blank sheet has a shape to cover two opposing side surfaces of a group of packaging containers which have been stacked on the blank sheet in a predetermined packing pattern. In the case of a wrap-around blank, the blank sheet has a shape to wholly cover a group of packaging containers which have been stacked on the blank sheet in a predetermined packing pattern. For various types of cardboard cases, the cardboard blank comprises flaps which need to be folded in order to form the desired shape of the case.

An example of flap folding is described in CA2771449 by the same applicant. According to this disclosure, L-shaped flap folders are activated by a pneumatic actuator pushing the cardboard case upwards. During flap folding, the cardboard case is stationary in the machine feed direction. Due to different customer requirements in terms of sizes and dimensions of the cardboard cases, the above-described prior art flap folders need to be adjusted accordingly if a producer decides to change the physical dimensions of the cases to be manufactured. There is thus a need for an improved cardboard packer, and in particular for an improved flap folding unit, which can be used for different dimensions of the cardboard case.

Summary

It is an object of the invention to at least partly overcome one or more of the above-identified limitations of the prior art. In particular, it is an object to provide a cardboard packer which allows for accurate folding of the flaps of the cardboard case, independently of the dimensions of the cardboard case.

According to a first aspect, a flap folding unit is provided. The flap folding unit comprises at least one flap folding device having a disc-like member being configured to be arranged in a first position to urge passing front flaps of an associated cardboard case to fold, and in a second position to allow unfolded rear flaps of the associated cardboard case to pass the disc-like member.

The disc-like member may comprise a convex portion and a recessed portion. Due to different geometries along a full revolution, engagement of the disc-like member with passing flaps can be controlled.

The convex portion may be a section having a circular periphery.

The disc-like member may be configured to rotate from its second position to its first position, thereby urging rear flaps of the associated cardboard case to fold.

The disc-like member may be connected to a link arm. The link arm may extend substantially parallel with a cardboard case feeder. In an embodiment, the link arm is pivotally supported.

The flap folding device may comprise two spaced apart flap folding devices. Hence, each flap folding device can cause folding of flaps on a specific side of the cardboard case.

The flap folding devices may consequently be arranged on opposite sides of a feeder (60).

Both flap folding devices may be driven by a common electrical motor. Further, a controller may be provided and configured to control rotation of the disc-like member.

According to a second aspect, a cardboard packer is provided. The cardboard packer comprises a flap folding unit according to the first aspect.

According to a third aspect, a method for performing flap folding is provided.

The method comprises feeding an unfolded flap to pass a convex portion of a disc-like member thereby urging the flap to fold. Once the flap has passed the convex portion, the method performs rotation of the disc-like member such that a recessed portion of the disc-like member is facing a transport area of one or more flaps, and once an unfolded rear flap has passed the recessed portion, the method performs rotation of the disc-like member such that the convex portion will accelerate and reach the rear flap from behind, causing the rear flap to fold.

The method may further perform final rotation of the disc-like member for returning the disc-like member to its idle position where the convex portion is ready to engage with a passing front flap.

According to a fourth aspect, a non-transitory computer-readable storage medium is provided, storing one or more programs configured for execution by one or more processors. The one or more programs comprises instructions for controlling the position of a disc-like member such that a passing unfolded flap engages with a convex portion of the disc-like member thereby urging the flap to fold, and once the flap has passed the convex portion, for controlling rotation of the disc-like member such that a recessed portion of the disc-like member is facing a transport area of one or more flaps, and once an unfolded rear flap has passed the recessed portion, for controlling rotation of the disc-like member such that the convex portion will accelerate and reach the rear flap from behind, causing the rear flap to fold.

Still other objectives, features, aspects and advantages of the invention will appear from the following detailed description as well as from the drawings.

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example, with reference to the accompanying schematic drawings, in which

Fig. 1 is a schematic view of a cardboard packer according to an embodiment;

Fig. 2 is an isometric view of a cardboard package produced by a cardboard packer;

Fig. 3 is a top view of a blank to be fed to a cardboard packer, and to be used to form a cardboard case;

Figs. 4a-d are schematic side views of how a cardboard blank is transformed to a cardboard case by means of a cardboard packer according to an embodiment;

Fig. 5 is a top view of a parts of a cardboard packer, having a flap folding unit according to an embodiment;

Figs. 6-10 are schematic top views of the flap folding process according to an embodiment; Fig. 11 is an isometric view of a flap folding unit according to an embodiment; and

Fig. 12 is a schematic view of a method for a cardboard packer.

Detailed description

With reference to Fig. 1 a cardboard packer 10 is illustrated. The cardboard packer 10 is configured to transform a cardboard blank to a cardboard package, as will be explained in the following.

The cardboard packer 10 is fed with a blanks magazine 12. The magazine 12 contains a number of separate blanks, stacked on top of each other in the magazine 12. The cardboard packer 10 is also receiving a flow of individual packages 20, such as carton packages 20 filled with a liquid food product or other suitable content, may it be in solid form or in liquid form.

The cardboard packer 10 comprises a blank picker 14 which is configured to access the magazine 12 and to grip one blank 50 at the time, and to move the blank 50 from the magazine 12 to a blank feeder 16. The blank feeder 16 is preferably configured to perform initial folding and forming of the blank towards the final cardboard package 30. Hence, the feeder 16 is in some way configured to also receive the carton packages 20, and to arrange the carton packages 20 within the cardboard package 30.

A flap folding unit 100 is provided along the transport path of the feeder 16. As is clear from Fig. 1, the cardboard packer 10 also includes a control unit 40 for controlling the operation of the flap folding unit 100, at least.

In Fig. 2 a cardboard package 30 is shown. The cardboard package 30 is representing only one example of how a blank 50 can be formed into an enclosing structure for a plurality of individual packaging containers 20 (in this example 12 pieces).

In Fig. 3 an example of a cardboard blank 50 is shown. The cardboard blank 50 is in the form of planar sheet, comprising a plurality of features to assist in forming the blank 50 into a three-dimensional body.

A first crease line 51a is arranged transverse to separate a rear panel 52a from a bottom panel 52b. Similarly, a second crease line 51b is arranged in parallel, but spaced apart from the first crease line 51a to separate the bottom panel 52b from a front panel 52c. A third crease line 51c is arranged in parallel, but spaced apart from the first and second crease lines 51a-b to separate the front panel 52c from a top panel The blank 50 is provided with a plurality of flaps 53-55. Front flaps 53a extend laterally on each side of the front panel 52c, while rear flaps 53b extend laterally on each side of the rear panel 52a. Bottom flaps 54a extend laterally on each side of the bottom panel 52b, while top flaps 54b extend laterally on each side of the top panel 52d. Yet further, a closing flap 55 is extending longitudinally from the top panel 52d.

Now turning to Figs. 4a-d, the process of forming a cardboard case is schematically illustrated. It should be noted that the described process is configured for blanks 50 of the type shown in Fig. 3; should other blanks 50 be used, the process of forming a cardboard case may be adjusted.

In Fig. 4a a plurality of packaging containers 20 are positioned onto the bottom panel 52b of the blank 50. The rear panel 52a and the front panel 52c are folded approximately 90° from the bottom panel 52b.

In Fig. 4b it is shown how the front flaps 53a and the rear flaps 53b have been folded inwards, towards the packaging containers 20.

In Fig. 4c, the top panel 52d is folded downwards and towards the upper portion of the packaging container 20.

In a last step, shown in Fig. 4d, the top flaps 54b are folded downwards while the bottom flaps 54a are folded upwards. Also, the closing flap 55 is folded downwards. Optionally, the top flaps 54b and the bottom flaps 54a are sealed to the front and rear flaps 53a-b, and the closing flap 55 may be sealed to the rear panel 52a.

Now, with reference to Fig. 5 and onwards, details of the flap folding unit 100 will be given. The flap folding unit 100 is configured to fold the front and rear flaps 53a- b of the blank 50, although it should be understood that the flap folding unit 100 could be used to fold any kind of suitable flap.

In Fig. 5 a schematic top view of the feeder 16 is shown; the transport direction is indicated by the block arrow. The feeder 16 receives a flow of blanks 50 (as shown in Fig. 1), and the blanks 50 are transformed into closed cardboard cases 60 during their transport along the feeder 16. Hence, as indicated in Fig. 5 a leading soon-to-be- formed cardboard case 60a is followed by a trailing soon-to-be-formed cardboard case 60b.

The flap folding unit 100 is arranged along the transport path of the feeder 16.

In particular, the flap folding unit 100 comprises a first flap folding device 110a on a first side of the feeder 16, and a second flap folding device 110b on the opposite side of the feeder 16. As can be seen in Fig. 5, the trailing cardboard case 60b is arranged with its front and rear flaps 53a-b still unfolded. However, once the cardboard case passes the flap folding unit 100, the front and rear flaps 53a-b will be folded due to the action of the flap folding unit 100. This is illustrated for the leading cardboard case 60a.

As will be explained in the following, operation of the flap folding unit 100 is controlled by means of a controller 120. The controller 120 forms part of the flap folding unit 100, or is connected thereto, in order to transmit control signals to driving components of the flap folding unit 100.

The flap folding unit 100 is shown in Fig. 6. The flap folding unit 100 comprises a first flap folding device 110a and a second flap folding device 110b. The flap folding devices 110a-b are arranged on opposite lateral sides of the feeder 16, such that the first flap folding device 110a will act on one side of the cardboard case 60, while the second flap folding device 110b will act on the opposite side of the cardboard case 60.

As can be seen in Fig. 6, the flap folding devices 110a-b are identical, at least with regards to how they act on the cardboard case 60 and engage with the respective flaps 53a-b.

As will be further explained with regards to Fig. 11, the flap folding unit 100 comprises a drive means 130, preferably in the form of an electrical motor. The electrical motor 130 is powered by a power supply (not shown), and the electrical motor 130 is connected to the controller 120 to receive control signals.

Again referring to Fig. 6, a flap folding device 110a-b comprises a disc-like member 140. Reference numerals are only inserted for the left flap folding device 110a, although the other flap folding device 110b comprises the same components.

The disc-like member 140 has a convex portion 142 and a recessed portion 144. The convex portion 142 is preferably a section of a circular periphery, while the concave portion 144 is a cut-out from the circular periphery. As shown in Fig. 6, the convex portion 142 extends slightly less than 180°. However, other extensions of the convex portion 142 are also possible. The recessed portion 144 has a curved shape, such that the disc-like member 140 exhibits a claw shape.

The disc-like member 140 is rotationally supported, and driven by the electrical motor 130. The rotational axis of the disc-like member 140 is preferably coinciding with the center point of the disc-like member 140; otherwise the convex portion 142 would move in an eccentric motion, possibly not supporting the flap 53a after it has been folded. At the position of the rotational axis R, the disc-like member 140 is rotationally connected to a pivoting lever 150, which in turn is connected to a link arm 152. The link arm 152 extends substantially in parallel with the feeder 16, i.e. parallel to the direction by which the cardboard case 60 is transported. However, as the disc-like member 140 rotates by activation of the electrical motor 130, the pivoting lever 150 will pivot thereby causing the link arm 152 to pivot as well. The direction of the link arm 152 will thereby deviate slightly from a strict parallel alignment with the longitudinal axis of the feeder 16. As can be seen in Fig. 6, the link arm 152 is pivotally supported by means at a pivot joint 154 arranged off-center the longitudinal axis of the link arm 152.

As the cardboard case 60 is approaching the flap folding unit 100, the front flaps 53a (still being unfolded) will come into contact with the convex portion 142 of the disc like member 140. During this motion of the cardboard case 60, the disc-like member 140 is kept stationary. Due to the convex shape of the disc-like member 140, i.e. the convex portion 142 is located such that the flaps 53a will engage with it, the flaps 53a will be urged to fold as the cardboard case 60 moves forward.

A subsequent position of the cardboard case 60 is shown in Fig. 7. In this position the feeder 16 has moved the cardboard case 60 to a position where the front flaps 53a have been folded entirely by the curved portion 142 of the disc-like member 140. So far, the disc-like member 140 has not rotated.

Once the cardboard case 60 has moved to a position where the front flaps 53a have been fully folded, i.e. immediately after the position shown in Fig. 7, the disc-like member 140 is kept stationary in order to support and guide the loaded packaging containers to secure that they do not move out from the cardboard case 60. When the rear flaps 53b are approaching the disc-like members 140, the disc-like members 140 are rapidly rotated such that the rear flap 53b can pass the recessed portion 144 of the disc-like member 140. Hence, the rotation of each disc-like member 140 is synchronized with the motion of the rear flaps 53b, which also means that it will be possible to adjust the motion of the flap folding devices 110a-b for different sizes of the cardboard case 60. This is shown in Fig. 8. The disc-like member 140 has rotated slightly more than 90° from its position shown in Fig. 7.

The flap folding device 110a is programmed, preferably by means of the controller 120, to perform a fast rotation of the disc-like member 140 from the position shown in Fig. 8, in a direction indicated in Fig. 8. As the cardboard case 60 moves forward, the convex portion 142 will accelerate and reach the rear flaps 53b from behind as is shown in Fig. 9. As the convex portion 142 moves faster than the cardboard case 60, the rear flaps 53b will be urged to fold in a forward direction as the cardboard case 60 moves forward, and as the disc-like member 140 pushes the flaps 53b in the forward direction at a speed greater than the speed of the cardboard case 60. When the disc-like member 140 reaches its initial position (i.e. the angular position shown in Fig. 6), the rear flaps 53b are fully folded and the rotational movement of the disc-like member 140 is stopped.

The same motion sequence is repeated for subsequent cardboard cases 60 being transported by the feeder 16.

The link arm 152 will assist in keeping the flaps 53a-b folded as they pass the disc-like member 140. As the front flaps 53a have been folded, they will be in contact with an inner side of the respective link arm 152 in order to assist in maintaining the folded position of the front flaps 53a. However, folding of the rear flaps 53b will also be assisted due to the shape of the link arm 152. In particular, with reference to Fig. 10 there will be a leading cardboard case in front of the cardboard case 60. As the cardboard case 60 is stationary on the feeder 16 such that packaging containers are allowed to be loaded onto the yet unfolded cardboard case 60, the leading cardboard case will be positioned such that the link arm 152 keeps the rear flaps 53b of the leading cardboard in their folded position. Of course, other means may be implemented for keeping the flaps in their folded position, such as linear motors that generate a pushing movement in the direction transverse to the direction by which the cardboard case 60 is transported, to push and keep the flaps against the case 60. Thus, the link arms 152 represents one of several embodiments for keeping the flaps in place.

Now turning to Fig. 11 , an embodiment of a flap folding unit 100 is shown separate from the feeder etc. The flap folding unit 100 has a first flap folding device 110a and a second flap folding device 110b. Each flap folding device has a disc-like member 140, as described earlier with reference to Figs. 6-10. The first flap folding device 110a is driven by means of an electrical motor 130. However, the first flap folding device 110a is connected to the second flap folding device 110b by means of a rotational shaft 132, such that rotation of the disc-like member 140 of the first flap folding device 110a is also transmitted to the second flap folding device 110b, thereby causing the disc-like member 140 of the second flap folding device 110b to rotate as well. For the transmission, worm gears or similar can be used. Instead of a mechanical transmission, it would also be possible to use separate motors for each flap folding device 110a-b. Now turning to Fig. 12, a method 200 for flap folding is schematically shown.

The method 200 comprises a first step 202 of feeding an unfolded flap 53a to pass a convex portion 142 of a disc-like member 140 in order to cause folding of the flap 53a. The convex portion 142 is preferably stationary during this step, although a rotational movement may also be considered. As soon as the folded flap 53a is transported beyond the convex portion 142, the method 200 performs a step 204 of rotating the disc-like member 140 such that a recessed portion 144 of the disc-like member 140 is arranged in a position facing a feeder 16. As an unfolded rear flap 53b is approaching, it will be allowed to pass the disc-like member 140 by no contact due to the provision of the recessed portion 144. As soon as the unfolded rear flap 53b has passed the recessed portion 144, the method 200 performs a step 206 of rotating the disc-like member 140 such that the convex portion 142 will accelerate and reach the rear flaps 53b from behind. Upon further rotation of the disc-like member 140, the rear flap 53b will be folded. After performing step 206, the method 200 will perform a step 208 of continued rotation of the disc-like member 140 for returning the disc-like member 140 to its idle position where the convex portion 142 is ready to engage with a passing front flap 53a.

The method 200 is repeated in order to perform flap folding of a sequence of passing articles, preferably cardboard cases 60 as described previously. From the description above follows that, although various embodiments of the invention have been described and shown, the invention is not restricted thereto, but may also be embodied in other ways within the scope of the subject-matter defined in the following claims.