TECHNICAL FIELD

The present invention relates to a machine and a method for producing packages of containers, in particular containers that contain pourable food products such as dairy products or the like.

BACKGROUND ART

Many liquid or pourable food products, such as fruit juice, UHT milk, wine, tomato sauce, etc., are sold in containers made of sterilized packaging material .

A typical example of this type of container is the parallelepiped-shaped container known as Tetra Brik or Tetra Brik Aseptic (registered trademarks) , which is made by folding and sealing laminated strip packaging material .

Once formed, filled and sealed, these containers are housed in groups inside respective packages for delivery to sales outlets.

One kind of package - the so called gift-box package - comprises an outer box that defines an internal space and an inner box that receives a group of containers and is arranged inside the internal space of the outer box.

The package comprises a number of spacers interposed between the outer box and the inner box, so that the side walls of the inner box do not contact the side walls of the outer box. The spacers are usually resilient elements made of plastic material.

One of the side walls of the outer box - intended to be the front wall - may have an opening through which the consumer can see the containers, the containers being placed at a certain distance from the front wall.

The containers may be placed in the inner box so as to form a plurality of layers, for example two layers superimposed on each other.

In the prior art, the gift-box packages are made by placing a group of containers on a first blank, in particular on a base panel element thereof. The blank is then wrapped around the group of containers to form the inner box. The filled inner box is then placed on a second blank and the latter is wrapped around the inner box so as to form the outer box. If two layers of containers are provided, an intermediate flat separating element (usually a carton sheet) is placed between the layers.

A drawback of the known procedures to form the packages referred to above is that folding the first blank around the containers to obtain the inner box and subsequently folding the second blank around the inner box to form the outer box may be quite time consuming and consequently limit productivity of the packaging line .

DISCLOSURE OF INVENTION

It is an object of the invention to provide a machine and a method for producing packages of containers which can expedite the production process.

It is another object of the invention to provide a machine and a method for producing packages of containers which achieve a reduction in production costs.

According to a first aspect of the invention, there is provided a machine for producing packages of containers, in particular containers of pourable food products, comprising:

a first feeding device for feeding a plurality of containers ,

a second feeding device for feeding a succession of empty inner boxes,

a filling station having a manipulator configured to pick up at least one group of containers fed by the first feeding device and to release the at least one group of containers in at least one respective inner box fed by the second feeding device,

a packing station in which each inner box filled with the containers is enclosed into a respective outer box having an open lid, and

- a closing station located downstream of the packing station for closing the lid of each outer box to obtain a closed package.

Owing to the first aspect of the invention, packages having an inner box filled with a plurality of containers and an outer box receiving the inner box can be produced easily at relatively high production rates. In particular, there is no need to fold a blank around the containers in order to obtain the inner box, which can be a quite time consuming operation, because the containers are released into an already formed inner box. If the packing station is configured to enclose the filled inner box into an already formed outer box, the packing operations are further simplified, because there is no need to fold a respective blank around the inner box to obtain the outer box.

According to a second aspect of the invention there is provided a method for producing packages of containers, in particular containers of pourable food products, comprising the steps of:

feeding a plurality of containers towards an operative region,

feeding a succession of empty inner boxes towards the operative region,

- in the operative region, filling each inner box with at least one group of containers of said plurality of containers,

enclosing the filled inner boxes into respective outer boxes each having an open lid, and

closing the lid of each outer box to obtain a closed package.

The method according to the second aspect of the invention allows obtaining the advantages already discussed with reference to the machine according to the first aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred, non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:

- Figures 1 and 2 are different views of a machine according to the invention;

- Figure 3 is an enlarged view of a part of the machine of Figures 1 and 2;

- Figures 4A to 4F show a succession of steps carried out by a manipulator of the machine of Figures 1 and 2 ;

- Figure 5 shows a blank used for an inner box processed in the machine and method according to the invention;

- Figures 6 and 7 show an inner box processed in the machine and method according to the invention and made by folding a blank such as the one of Figure 5; - Figures 8A to 8F show a sequence of steps carried out when filling the inner box of Figures 6 and 7 with containers .

BEST MODES FOR CARRYING OUT THE INVENTION

With reference to the Figures, a machine for producing packages of containers according to the invention is shown, which is indicated with reference 1.

Preferably, the package can be a so called "gift box" package, namely a box used for example for promotional or seasonal gifts or again for birthday or Christmas gifts.

With the term "containers" it is intended any container suitable for being included in the box. Preferably, the box is designed to contain a plurality of identical containers in a rectangular array arrangement and on two or more layers.

Preferably, the containers are filled with pourable food products (for example dairy products such as milk or yogurt, juice or the like) . The containers may be parallelepiped-shaped, known as Tetra Brik or Tetra Brik Aseptic (registered trademarks) , which are made by folding and sealing laminated strip packaging material. The containers can however also have different shapes, for example a substantially parallelepiped shape with non-sharp edges.

As shown in Figures 1 and 2, the machine comprises several stations which, according to a flowing direction of the products, are the following:

- an inlet station 2 for receiving a continuous flow of containers 100 which, in the described embodiment, travel in an erected position;

a partition device 3 intended for gathering the containers 100 of the continuous flow in ordered groups a lateral pushing device 4 for expelling the containers 100 from the partition device 3 towards a pick-up area 5, the lateral pushing device 4 defining a first feeding device active on the containers 100;

- a filling station 6 having a manipulator 7 configured to pick up at least one group of containers 100 fed by the first feeding device 4 and to release the at least one group of containers 100 in at least one respective empty inner box 200 fed by a second feeding device 8; - a packing station 9 configured to enclose each inner box 200 filled with the containers 100 into a respective outer box 300 having an open lid;

- a closing station 400 for closing the lid of each outer box 300 to obtain a closed package.

The focus of the invention is directed to the filling station 6 and to the packing station 9, which will be described in more detail in the following and can be better seen in Figure 3.

At the filling station 6 the manipulator 7 is actuated to transfer groups of containers 100 from the first feeding device 4 to respective empty inner boxes 200 fed by the second feeding device 8.

To achieve this, the manipulator 7 has one or more grippers 10 (also shown in Figures 4A to 4F and 8A to 8F) movable between a pick-up position at the pick-up area 5, in which the gripper 10 picks up a respective group of containers 100 from the first feeding device 4, and a release position, in which the gripper 10 releases at least part of the group of containers 100 into an empty inner box 200 fed by the second feeding device 8.

In the embodiment shown in the drawings, the manipulator has four grippers 10 arranged in a row and designed to move simultaneously to transfer respective groups of containers 100.

The manipulator 7 also comprises a common linear guide or rail 11, movable between the pick-up position and the release position by means of a respective actuator 12, and the grippers 10 are slidably mounted on the common linear guide 11 so as to be moved along the linear guide 11 or change the distance or pitch between the grippers 10 from the pick-up position to the release position. This compensates for any different distance (pitch) existing between the succession of groups of containers 100 at the first feeding device 4 and the empty inner boxes 200 at the second feeding device 8.

Preferably, the direction of movement of the linear guide 11 by the actuator 12 is perpendicular to the sliding movement of the grippers 10 on the linear guide 11.

More in detail, the linear guide 11 can translate on a plane which is perpendicular to the linear guide 11 itself, and this movement can be represented by a first translation in a horizontal direction "Fl" and a second translation in a vertical direction "F2", the linear guide 11 being capable of following any combination of both said sliding movements.

Moreover, the linear guide 11 defines a horizontal translating direction "F3" for the grippers 10, said translating direction "F3" being perpendicular to said horizontal translating direction "Fl" and to said vertical translating direction "F2".

Moreover, each gripper 10 is configured to pick-up and hold a group of containers 100 arranged on one or more layers and is also configured to pick-up and release single layers of said containers 100. This will be relevant in the following part of the description. In the filling station 6 the empty inner boxes 200 are fed by the second feeding device 8 in which the empty inner boxes are each shaped to define an internal volume substantially coinciding with its containing volume in use. In other words, the second feeding device 8 feeds the empty inner boxes 200 already at least in part formed to define their inner volume.

To allow an insertion of the grippers 10 with the groups of containers 100 in the empty boxes 200, the second feeding device 8 has a stepwise advancing movement .

Preferably, the empty inner boxes 200 are obtained in an inner box forming device 15, located upstream of the second feeding device 8 and configured to receive flat blanks 210 and to fold the flat blanks 210 to obtain the inner boxes 200. The inner boxes 200 obtained by the inner box forming device 15 have at least a bottom wall 220 and two opposite upright side walls 230, 240 (Figures 5 to 7) . Preferably, the empty inner box 200 also has two additional side walls 250, 260 to obtain a closed square or rectangular sectional outline, in which each of the additional side walls 250, 260 can be obtained by two half walls, each connected to a respective side wall 230, 240.

Furthermore, the empty inner box 200 also has side projections on the side walls which serve to abut against the inner surface of the corresponding outer box 300 to hold the inner box, when filled, in a stable position within the outer box 300.

Preferably, the second feeding device 8 is equipped with divaricating means 13 active on the opposite upright side walls 230, 240 to divaricate them at least in the filling station 6 (namely in the position in which the inner box 200 is to be filled with the containers 100) so as to achieve a divergent configuration of the side walls 230, 240 departing from the bottom wall 210. This makes it easier to insert the groups of containers 100 in the inner box 200 so that the need of further aids such as converging guides or funnels is avoided.

The divaricating means 13 can comprise grasping fingers 14, shown in Figures 8B and 8C, configured to act on an upper edge of the side walls 230, 240 and movable towards and away from each other. Alternatively, other solutions can be implemented, for example suction cups (not shown) or even only one grasping finger or suction cap can be used. In the latter case, the divaricating action is performed by moving only one upright side wall 230, 240.

Advantageously, the filling station 6 comprises an auxiliary device configured to mechanically place a separating wall or layer 270 in the inner box 200 between two adjacent layers of containers 100.

The auxiliary device is operated to place the separating layer 270 on a first layer of containers 100 already inserted in the inner box 200 and before a second layer of containers 100 is arranged on the first layer of containers 100.

According to the invention, the auxiliary device comprises a folding member (not shown) designed to push and fold a separating flap of an upright side wall 230 of the inner box 200 from a first position, in which the separating flap is aligned with the respective upright side wall 230 of the inner box 200 (Figure 6) , and a second position, in which the separating flap extends in the inner volume of the inner box 200 to cover a first layer of containers 100 previously released in the inner volume of the inner box 200 (Figure 7) .

Preferably, and as shown in the Figures, the machine also comprises an outer box forming device 18, located upstream of the packing station 9 and configured to receive flat cartons 310 and to expand the flat cartons 310 to obtain outer boxes 300 each shaped to define an internal volume substantially coinciding with the containing volume of the outer box in use.

To transfer the folded outer box from the outer box forming device 18 to the packing station 9, a third feeding device 19 is used which preferably displaces the outer boxes 300 in a configuration with an open side facing upwards .

In the disclosed embodiment, the inner boxes 200 filled with the containers 100 are then inserted into the respective pre-shaped outer boxes 300 by an inserting device 20. The inserting device 20 is located above the third feeding device 19 and has a movable gripper 21 displaceable in a vertical direction (preferably along a fixed vertical axis) to slide between a raised position (Figure 3) , in which the movable gripper 21 grasps and holds a filled inner box 200 coming from the filling station 6, and a lowered position in which the movable gripper 21 enters an empty outer box 300 fed by the third feeding device 19 to insert the filled inner box 200 therein.

Downstream of the inserting device 20, a closing device located in the closing station 400 closes the upper aperture of the outer box 300 by folding at least one closing flap thereof.

The inlet feeding device 4, the manipulator 7, the packing station 9 and the inner box forming device 15 are arranged in a central region of the machine 1. This central region can be defined as an operative region of the machine 1. The containers 100, the flat blanks 210 for forming the inner boxes 200 and the flat cartons 310 for forming the outer boxes 300 are conveyed towards this central region from different directions.

In particular, as shown in Figure 1, the containers 100 are conveyed through the inlet station 2 towards the first feeding device 4 along an inlet path extending in a first direction Gl .

The flat blanks 210 are conveyed towards the inner box forming station 15 along an entry path extending in a second direction G2, which is parallel to the first direction Gl .

The flat cartons 310 are conveyed towards the packing station 9 along an introduction path extending in a third direction G3, opposite the first direction Gl and the second direction G2.

The inlet path along which the containers 100 are initially conveyed and the entry path along which the flat blanks 210 are initially conveyed are located on the same side of the central region of the machine 1.

The introduction path along which the flat cartons 310 are initially conveyed is located on an opposite side of the central region of the machine 1 relative to the inlet path of the containers 100 and the entry path of the flat blanks 310.

This allows a particularly compact layout of the machine 1 to be obtained.

The packing method according to the invention is now described, with reference to the structural parts of the machine as above described.

The containers 100 are conveyed by the first feeding device 4 that releases the containers 100 at the filling station 6. In the latter, the manipulator 7 picks the containers 100 up in groups.

Preferably, the containers 100 are organized in groups already at the exit of the first feeding device 4 (for example, in one or more groups in each of which the articles are arranged in one or more rows) .

At the same time, a succession of empty inner boxes 200 is fed to the filling station 6 by the second feeding device 8. In the filling station 6, each inner box 200 has already been shaped (by means of the inner box forming device 15) as a box-like container, so as to define an internal volume substantially coinciding with the containing volume of the inner box 200 in use.

The manipulator 7 can therefore fill each inner box

200 by picking up, for each gripper 10, at least one group of containers 100 fed by the first feeding device 4 and by releasing the at least one group of containers 100 in a respective inner box 200 fed by the second feeding device 8.

In more detail, according to a preferred embodiment, each group of containers 100 transferred by each gripper 10 of the manipulator 7 comprises at least two layers of containers 100, for example two layers as shown in Figures 4F and 8A. The containers 100 are arranged in the required number of layers by the manipulator 7 in a sequence of steps as disclosed below.

As shown in Figures 4A and 4B, the manipulator 7 grasps and raises, by means of each gripper 10, a first layer of containers 100 coming out from the first feeding device 4. Then, as shown in Figures 4C and 4D, each gripper 10, in a raised position, waits until a second layer of containers 100 is released under the gripper 10 by the first feeding device 4. The gripper 10 is now lowered to release the first layer of containers 100 on the second layer of containers 100, as shown in Figure 4E. At this point the gripper 10 can grasp both the layers of containers 100, as shown in Figure 4F, and transfer both the layers of containers 100 towards the inner box 200 to be filled (Figure 8A) .

In the shown embodiment, each layer of containers is made by six containers 100 (3x2) and the views of Figures 4A to 4F, showing three containers for each layer, is rotated by 90° relative to the views of Figures 8A to 8F, showing two containers for each layer.

Preferably, the inner box 200 is conveyed in a stepwise manner by the second feeding conveyor 8 and receives the containers 100 during a stationary phase of the stepwise movement.

Preferably, during the insertion of the gripper 10 in the inner box 200, at least one of the upright side walls 230, 240, preferably both of them, are outwardly bent by the divaricating means 13 to obtain the divergent configuration of the side walls 230, 240 (Figure 8B) .

In more detail, the gripper 10 of the manipulator 7 enters the inner box 200 from above, in particular from the open top of the inner box 200, until the lowermost layer of containers 100 grasped by the gripper 10 is released on the bottom wall 220 of the inner box 200 (Figure 8C) .

After releasing the lowermost layer of containers 100, the gripper 10 still grasps the uppermost layer of containers 100 to pull them away from the bottom wall 220.

In detail, the gripper 10 is raised to an extent sufficient to reach a position above the separating flap 270 of the upright side wall 230.

Then the folding member included in the auxiliary device pushes the separating flap 270 inwardly to fold it on the first layer of containers 100 laying on the bottom wall 220 (Figure 8D) .

After the separating flap 270 has been placed in a substantially horizontal position (namely covering the first layer of containers 100) the gripper 10 is lowered again and releases the second layer of containers 100 on the separating flap 270 (Figure 8E) .

Then the gripper 10 is moved away to perform another filling step (figure 8F) .

It is stressed that, irrespective of whether the upright side wall 230 bearing the separating flap 270 is arranged vertically or inclined due to the outwardly bending action of the divaricating means 13, the separating flap 270 is bent inwardly until it reaches a substantially horizontal position, in which the separating flap 270 covers the first layer of containers 100.

In an alternative embodiment, which is not shown, the gripper 10, after grasping two or more layers of containers 100 together at the pick-up position, releases a first layer of containers 100 in a first inner box 200 and then releases a second layer of containers 100 in a second inner box 200, for example arranged downstream of the first inner box 200. The second inner box 200 has already received the first layer of containers 100 by a preceding gripper 10 of the same manipulator. The next box 200 reaches the position of the first inner box 200 in a subsequent step of the stepwise movement of the second feeding device 8. The filled inner box 200 is then sent to the packing station 9, in a position in which the movable gripper 21 of the inserting device 20 can grasp and hold the filled inner box 200. Then, the movable gripper 21 is lowered so that the filled inner box 200 is inserted in a pre-formed outer box 300, the latter being arranged with an upwardly-facing aperture, so that the filled inner box 200 is enclosed by the outer box 300 at least at the bottom side and at the lateral sides.

In an embodiment, the outer boxes 300 are obtained out of flat cartons, namely pre-arranged flat cartons, already configured to quick assume a box shape by spreading apart the two flat surfaces of each carton. Thus, each flat carton may originate, for example, a tube having a square or rectangular section starting from an elongated section.

In an alternative embodiment, the outer box forming device 18 forms each outer box 300 by folding a flat blank .

Each filled outer box 300 is sent to the closing station 400 in which the outer box 300 is closed, for example by application of a covering or deck or by folding a closing flap forming part of the original flat carton 310 of the outer box 300.

According to an advantageous feature of the invention, the blank 210 of the inner boxes 200 is shaped in such a way that, after formation of the inner boxes 200, the latter has lateral spacers or distancing flaps 280 outwardly protruding so as to abut the inner surface of the respective outer box 300. The spacers 280 serve to keep the inner box 200 in a stable and predetermined position within the respective outer box 300. Preferably, the spacers 280 have a lower chamfered portion 285 that helps to guide the inner box 200 during the insertion in the outer box 300.

By providing a separating flap 270 and spacers 280 as foldable portions of the blank 210, there is no need to provide separating elements and/or spacers distinct from the blank 210 of the inner box 200. This reduces the number of carton elements that need to be stored.