DE102011052101B4 - Shrinkage device with container cooling - Google Patents

Abstract

Shrinking device (1, 15a, 15b, 15c, 15d) for shrinking an outer packaging (7) around a collection of articles (6) into a container (5*), the shrinking device having a transport route (10), an entrance area (3), a shrink tunnel (2) and an exit area (4, 16a, 16b, 16c, 16d), articles (6) combined with an outer packaging (7) being subjected to hot air in order to shrink the outer packaging (7), the transport route ( 10) serves for the uninterrupted transport of the containers (5*) through the entrance area (3), the shrink tunnel and the exit area (16a, 16b, 16c) of the shrink device (15a, 15b, 15c), in the exit area (4, 16a, 16b , 16c) at least one first coolant device (20) is arranged above the transport route (10), through which the containers (5*) can be acted upon by a cooling air flow (22) from above, the transport route (10) being a continuous and coolant device permeable means of transport and wherein in the exit area (16a, 16b, 16c, 16d) of the shrinking device (15a, 15b, 15c, 15d) below the means of transport at least one second coolant device (25) is arranged, through which the bottom area of the container (5*) can be acted upon from below with a cooling air flow (26), with at least a first upper coolant device (20*) and a second lower coolant device (27*) being arranged directly opposite one another directly after the exit of the shrink tunnel, which first upper coolant device (20* ) produces a coolant flow directed largely vertically downwards and which second lower coolant device (27*) produces a coolant flow directed largely vertically upwards.

Description

The present invention relates to a shrinking device for shrinking an outer packaging around a set of articles. The shrinking device comprises a transport route, an entrance area, a shrink tunnel and an exit area, with at least one first coolant device being arranged in the exit area above the transport route, through which coolant can be applied to the article assembly from above.

State of the art

When packaging items, especially beverage containers, bottles, etc. into containers, the items are put together in the desired manner and wrapped in shrink film. The shrink film is shrunk around the items by supplying hot air in a shrink tunnel.

The containers are transported through the shrink tunnel on a conveyor device. Due to the constant supply of hot air, the conveyor chain heats up. This can lead to problems because, due to excessive local heating, the shrink film in the bottom area of the container sticks to the conveyor device, which can result in damage to the shrink packaging. For this reason, devices are known in which the conveyor device is specifically cooled.

After the shrink containers leave the shrink tunnel, they must cool down relatively quickly before they are fed to further processing devices, such as palletizing devices or similar. The shrink film itself has a so-called memory effect. When producing shrink film, the film material used is heated, stretched and then cooled again. During the shrinking process, the shrink film wrapped around the items is reheated. During the subsequent cooling, the shrink film returns to its unstretched original state, with the molecules re-arranging themselves in their actual original shape. The shrinking process therefore consists of heating and cooling the shrink film that is wrapped around the containers. A shrink package is only stable when the shrink film has cooled down to such an extent after being heated that no further deformation (contraction of the shrink film) takes place and the shrink package is therefore firm and stable. This is particularly necessary because shrink containers with shrink film that are still warm are very unstable and therefore very sensitive to forces of any kind. Such unfavorable forces also act against the shrinkage process that is still warm or have not yet completely cooled down and thus worsen the result or lead to defective packaging. Such unfavorable forces on the shrink packs can be found, for example, at transitions between individual conveyor belts adjacent to the shrink tunnel, via which the shrink packs are fed to further processing devices. Because the shrink film in the bottom area of the container has not yet completely cooled down, it can easily be damaged. In this bottom area, where the shrink film ends overlap, the time required for complete cooling is longer than in the other areas (top, front sides of the container, etc.). As the shrink film cools, the film contracts even further and is firmly fixed or placed around the packaged items.

This necessary cooling of the containers can be achieved, for example, by having a so-called cooling section after the shrink tunnel. This is often extended due to the given ambient temperatures or the thickness of the film used to ensure that the shrink containers are cooled down sufficiently before they are transferred to the next conveyor belt. The conveyor with which the shrink packages are moved through the shrink tunnel and through the cooling section is a single conveyor section, the length of which is designed according to the respective requirements. If necessary, an adjustment of the conveyor route may be necessary when changing products.

According to the known prior art, one or more fans, in particular axial fans or radial fans or the like, are used after the shrink tunnel, above the conveyor, which blow cooling air onto the product from above. However, the underside of the container is not covered by this cooling air, so that the containers cool down less in this area. As a result, the containers in this area have less stability, which leads to problems, especially when transferring them to a downstream conveyor belt, a container turning station or similar. This problem is generally solved by the combination of fans mounted in series and an extension of the cooling section of the above type at the exit of the shrink tunnel. An extension of the cooling section is very complex because - as already described above - this entails an extension of the entire conveyor.

US 3,727,324 A describes a shrink tunnel that has an air curtain at the entrance and exit. The first air curtain at the entrance to the shrink tunnel is used to preheat the film in this area. The second air curtain at the exit of the shrink tunnel is used to cool the film in the exit area. In particular, a cooling arc is arranged at the exit of the shrink tunnel, through which cooling air is blown from above and from the sides onto the pallet with piece goods covered with shrink film.

DE 15 86 349 A describes a method for wrapping packages with plastic shrink film and applying warm air to the packages within a shrink tunnel. In particular, it describes the handling of an edge strip that projects beyond the end face of the respective packs, which is referred to as an overhang. For this purpose, there are several nozzles for directing air jets, with which the supernatant can be held and redirected.

DE 23 20 424 A1 describes a device for the continuous packaging of objects, which includes a shrink tunnel. Here, after the shrinking process, the packaged objects are also cooled, with a cooling arrangement arranged at the top directing cold air onto the wrapped objects in order to accelerate the cooling of the objects and their shrunk-on packaging.

Through JP H10 - 327 747 A a shrinking device with a shrink tunnel and a transport route is disclosed, which is used to shrink outer packaging around sets of items. In the exit area, the containers can be supplied with coolant from above and below the transport route.

Through DE 30 26 176 A1 Finally, a tunnel oven for the production of plate-like fabrics coated on both sides with a curable material is disclosed, which comprises a conveyor device for the fabrics and a heating device with a hot air supply. There is a cooling air supply on a side of a conveyor track of the conveyor device facing away from the heating device. This cooling air supply, which can have a row of nozzles extending parallel to the conveyor track, can in particular be arranged below the hot air supply.

The object of the invention is to cool containers effectively and on all sides in the exit area of a shrink tunnel or after they have left the shrink tunnel.

The above object is achieved by a shrinking device which comprises the features in claim 1. Further advantageous embodiments are described in the subclaims.

Description

The invention relates to a shrinking device for shrinking an outer packaging or a shrink film around a collection of items. The articles are preferably liquid containers, in particular beverage bottles, which are covered with shrink film and combined into containers. The shrinking device comprises a transport route over which the containers are transported in the transport direction via an entrance area into a shrink tunnel and via an exit area to further transport devices or other processing devices. In the exit area of the shrinking device, according to the known prior art, at least one first coolant device is arranged above the transport path, through which the containers are supplied with a coolant from above. Preferably, at least one fan or similar is arranged above the transport route, with which cold air is blown onto the warm containers coming from the shrink tunnel.

According to the invention, the transport route consists of a continuous, uninterrupted means of transport, i.e. a single conveyor belt or similar, on which the containers are transported through the entrance area, the shrink tunnel and the exit area to a transfer area. In the transfer area, the fully shrunk containers are transferred to another means of transport or to another processing device. The transport means of the shrinking device is permeable to a coolant. In the exit area of the shrinking device, at least one second coolant device is arranged below the transport means, through which the bottom area of the container is supplied with coolant from below. The additional coolant device allows the bottom area of the container to be specifically cooled. This was only inadequate or not possible at all with the previous cooling from above. Due to the cooling from below, the end faces and side surfaces of the lower areas of the containers are now subjected to more coolant, since the distance from the surface to be cooled to the coolant device is now significantly smaller.

The means of transport is preferably a conveyor belt, in particular an endless conveyor chain, a wire link belt, a mesh belt, a Sta roll chain or a similar suitable conveyor that is permeable to a coolant flow. The coolant used is in particular a cooling air flow which is generated by at least one blower, a fan, for example a cross-flow fan, a radial fan or an axial fan or the like.

The fan or similar can be arranged as a so-called internal fan directly below the transport path in such a way that it directs its coolant flow upwards towards the underside of the container. The fan can also be arranged outside the shrinking device and the cooling air can be directed to the desired locations via lines. For example, a cooling channel can be arranged under the transport route. The coolant is directed into the cooling channel and the coolant is applied to the bottom of the container via upwardly directed nozzles. It can be provided here that the nozzles are adjustable, in particular an adjustability of the nozzle angles and the size of the nozzle opening can be provided, so that the amount and the angle at which the coolant hits the underside of the container can be adjusted.

The coolant is preferably blown from below onto the bottom of the container at an angle of between 30° to 150° to the transport surface. The air sucked in by the fan is taken, for example, from the area of the machine frame below the conveyor belt. Alternatively, the air can also be taken from the environment or from another packaging device via side intake channels.

According to the invention, at least one upper and one lower coolant device are arranged directly opposite one another directly at the exit from the shrink tunnel. The upper coolant device produces a largely vertically downward flow of coolant. The lower coolant device produces a largely vertically upward flow of coolant. The two coolant streams thus form a coolant curtain, in particular an air curtain, at the exit of the shrink tunnel. This prevents the hot air from escaping from the shrinking tunnel in an uncontrolled manner and thus has a positive effect on the energy balance of the shrinking device.

In a particularly preferred embodiment, the coolant stream and/or the at least one second coolant device can be moved in the exit region of the shrinking device. In particular, the movement of the coolant flow and/or the movement of the at least one second coolant device is regulated or controlled analogously to the movement of the containers.

For example, the nozzles of the coolant device can be moved with the respective container in order to achieve a cooling effect on the container for as long as possible. According to one embodiment, for example, the blower is arranged movably below the transport means and moves parallel to the respective container.

In an alternative embodiment with a cooling channel, for example, only the nozzle openings above which the container is currently located are opened in order to generate the coolant flow only in these areas. It can be provided that the position of the containers on the means of transport is determined using sensors and transmitted to a control unit. The control unit controls the opening or closing of the corresponding nozzles, in particular taking into account relevant parameters of the device, for example taking into account the speed of the means of transport, etc. The sensors can be, for example, image-capturing sensors, and weight or pressure-sensitive sensors can also be used or other suitable sensors can be used. Such targeted control of the coolant is possible because the containers are transported at a distance from one another on the transport route. The spacing is particularly necessary in order to achieve all-round cooling of the container side surfaces, which are arranged largely perpendicular to the transport surface.

Furthermore, additional lateral coolant devices can be provided in the exit area of the shrinking device, so that coolant devices are arranged all around the transport route in this area. The various coolant devices are preferably arranged in a plane perpendicular to the transport plane, so that the containers pass through a cooling air curtain or cooling air shield and are supplied with cooling air from all sides, in particular from above and below and possibly from the sides. The coolant devices can, for example, be arranged approximately in a ring shape, an oval shape, a rectangular shape or the like around the transport plane.

Furthermore, it can be provided that the distance between the coolant devices and the containers can be adjusted according to the size and shape of the containers in order to optimally adapt the coolant supply to the respective containers. For example, at least one sensor can be used, which detects the size, shape, etc. of the containers at the exit of the shrink tunnel and transmits the determined data to a control unit. The control unit then regulates the position of the coolant devices and thus sets the optimal distance between the coolant devices and the containers.

• 1 zeigt eine schematische Ansicht einer Schrumpfvorrichtung mit nachgeordneter Transportvorrichtung gemäß dem bekannten Stand der Technik.
• 2 zeigt eine Vergrößerung des Ausgangsbereiches einer Schrumpfvorrichtung gemäß dem bekannten Stand der Technik.
• 3 zeigt eine schematische Teil- Ansicht einer erfindungsgemäßen Schrumpfvorrichtung.
• 4 zeigt eine schematische Teil- Ansicht einer weiteren Ausführungsform einer erfindungsgemäßen Schrumpfvorrichtung.
• 5 zeigt eine schematische Teil- Ansicht einer weiteren Ausführungsform einer erfindungsgemäßen Schrumpfvorrichtung.
• 6 bis 8 zeigen jeweils einen schematischen Querschnitt durch den Ausgangsbereichs einer Schrumpfvorrichtung.
• 9 zeigt eine weitere Ausführungsform einer erfindungsgemäßen Schrumpfvorrichtung.

In the following, exemplary embodiments will explain the invention and its advantages in more detail using the attached figures. The proportions of the individual elements in the figures do not always correspond to the real proportions, as some shapes are simplified and other shapes are shown enlarged in relation to other elements for better illustration.

• 1 shows a schematic view of a shrinking device with a downstream transport device according to the known prior art.
• 2 shows an enlargement of the output area of a shrinking device according to the known prior art.
• 3 shows a schematic partial view of a shrinking device according to the invention.
• 4 shows a schematic partial view of a further embodiment of a shrinking device according to the invention.
• 5 shows a schematic partial view of a further embodiment of a shrinking device according to the invention.
• 6 until 8th each show a schematic cross section through the exit area of a shrinking device.
• 9 shows a further embodiment of a shrinking device according to the invention.

Identical reference numbers are used for elements of the invention that are the same or have the same effect. Furthermore, for the sake of clarity, only reference numbers that are necessary for the description of the respective figure are shown in the individual figures. The embodiments shown merely represent examples of how the device according to the invention or the method according to the invention can be designed and do not represent a final limitation.

1 and 2 each show schematic views of a shrinking device 1 with a downstream transport device 12 according to the known prior art.

Articles, in particular beverage containers, bottles 6, cans or the like, are put together in groups and covered with shrink film 7. These item combinations are also referred to as containers 5. The containers 5 are fed in the transport direction TR on a means of transport, in particular a conveyor belt 10, via an entrance area 3 to a shrink tunnel 2. Heating means (not shown) are arranged in the shrink tunnel 2 and apply hot air to the containers 5, for example. As a result, the film 7 of the outer packaging shrinks and lies against the items on all sides, thus forming a finished container 5* or a packaging unit. In the exit area 4 of the shrinking device 1, fans 20 are arranged above the conveyor belt 10, with which cold air 22 is blown onto the warm containers 5* in order to cool them down before they are transferred to another conveyor belt 12 and thereby ensure that the containers 5 * are firm and stable before handover. By cooling the warm containers 5* after leaving the shrink tunnel 2 and before passing the containers 5* on to other devices - for example before transferring them to another conveyor belt 12 - the aim is to prevent them from being wrapped in still warm film 7* Containers 5* are unstable and can be damaged later.

3 shows a schematic partial view of a shrinking device 15a according to the invention. Here, the bottles 6 covered with shrink film 7 are in turn transported through a shrink tunnel 2, the shrink film 7 being shrunk around the bottles 6 and the finished container 5* is thus formed. The shrinking device 15a has fans 20 arranged in the exit area 16a above the conveyor belt 10, for cooling the containers 5* with a cooling air flow 22 directed towards the containers 5*.

The conveyor belt 10, on which the containers 5, 5* are conveyed through the shrinking device 15a, is designed to be air-permeable, for example it is a conveyor chain 11 or a mat chain conveyor, with openings being formed between the chain links. In the exit area 16a of the shrinking device 15a, coolant devices 25 are arranged below the conveyor belt 10. In the exemplary embodiment shown, there are blowers 27 which blow cooling air 26 upwards through the conveyor belt 10 from below. This allows the bottom area of the warm containers 5* in particular to be cooled. Furthermore, the lower areas of the end faces and side surfaces of the containers 5* are also supplied with more cooling air 22 and 26 by the cooling air flow 26, since the distance between the lower coolant device 25 and these areas is smaller than the distance between the upper coolant devices 20 and these areas.

The coolant device 25 is, for example, at least one fan, which is arranged below a perforated plate or directly below the conveyor belt 10 so that the cooling air 26 flows upwards in the direction of the warm Container 5* is blown. The exit angle α of the cooling air 26 preferably has an amount between 30° and 150° in relation to the transport plane.

4 shows a schematic partial view of a shrinking device 15b according to the invention. Here, a cooling channel 28 is arranged in the exit area 16b below the conveyor belt 10. Cold air is directed into the cooling channel 28 by an external or internal fan (both not shown). The cold air 26 is directed via nozzle openings 29 on the top of the cooling channel 28 through the conveyor belt 10 to the bottom area of the container 5*.

5 shows a schematic partial view of a shrinking device 15c according to the invention. In the exit area 16c of the shrinking device 15c, coolant devices 27, 27* with an upwardly directed coolant flow 26, 26* are arranged below the conveyor belt 10. Above the conveyor belt 10, coolant devices 20, 20* are arranged with a downward coolant flow 22, 22*. In particular, an upper coolant device 20* with a coolant flow 22* arranged largely vertically downwards and a lower coolant device 27* with a coolant flow 26* directed largely vertically upwards are arranged directly after the exit of the shrink tunnel 2. Furthermore, at least one further upper coolant device 20 and one further lower coolant device 27 are arranged in the transport direction TR with coolant flows 22, 26 directed at an angle downwards or upwards.

A so-called coolant curtain 30 is formed by the two coolant streams 22*, 26* directly in the exit area of the shrink tunnel 2. On the one hand, this coolant curtain 30 causes the warm containers 5* to cool directly from below and above and, on the other hand, it prevents warm air from escaping from the shrink tunnel 2. This effectively prevents heat loss, which means the energy costs for the shrink tunnel 2 can be reduced. The downstream coolant streams 22, 26 serve to further cool the container. In particular, the coolant flow 26 serves to cool the containers 5* from below in order to eliminate the problems described with regard to damage and/or undesirable deformation of the packaging film 7*.

6 until 8th each represent a schematic cross section through the exit area 16 of a shrinking device.

6 shows the schematic cross section through a shrinking device according to those in the 3 until 5 illustrated embodiments, in which at least one upper coolant device 20 is arranged above the transport plane formed by the conveyor belt 10 and at least one lower coolant device 25 is arranged below the conveyor belt 10. As a result, the containers 5* are supplied with coolant 22, 26 from above and below.

7 and 8th each show embodiments in which additional lateral coolant devices 40 are arranged on both sides of the transport plane formed by the conveyor belt 10. Through these lateral coolant devices 40, the side surfaces of the containers 5* can additionally be specifically cooled with coolant 42. The coolant devices 20, 25 and 40 can also be adjustable. In particular, the distance between the coolant devices 20 and 40 and the containers 5* can be adjusted according to the size of the containers 5*, so that the coolant supply can be optimally adapted to the respective containers 5*. In particular, a sensor 45 can be provided which detects the size and shape etc. of the containers 5* at the exit of the shrink tunnel. Based on the data determined by the sensor, a controller 50 regulates the position of the coolant devices 20 and 40 and thus sets the optimal distance between the coolant devices 20 and 40 and the containers 5*.

9 shows a further embodiment of a shrinking device 15d according to the invention. Here, the coolant device 25 arranged below the conveyor belt 10 is movable and / or controllable, so that cooling air 26 is blown onto the bottom area of the respective container 5 * only in the areas of the conveyor belt 10 on which a container 5 * is arranged. In the exemplary embodiment shown, for example, the fan 25 is moved in the transport direction together with the containers. The coolant device 25 is then moved again against the transport direction of the conveyor belt 10 to the exit of the shrink tunnel 2 and moved parallel to the next container 5* in the transport direction towards further processing devices, for example in the direction of the further conveyor belt 12.

According to a further embodiment, not shown, the coolant device can also have a plurality of nozzle openings along the transport route, which are activated one after the other, in particular depending on the position at which the respective container 5* is located. For this purpose, for example, a sensor can be provided which determines the position of the containers 5* and transmits the data to a control unit, which regulates the nozzle openings of a coolant channel or similar accordingly.

Furthermore, it can be provided that the coolant devices 20 arranged above the transport level can also be moved parallel to the transport route with the cooling air 22 directed downwards or can be regulated accordingly (also not shown).

The invention has been described with reference to a preferred embodiment. However, it will be apparent to one skilled in the art that modifications or changes may be made to the invention without departing from the scope of the following claims.

Reference symbol list

1

shrink device

2

Shrink tunnel

3

Entrance area

4

Exit area

5, 5*

Container/packaging unit

6

Bottle

7

Shrink film/packaging film

10

conveyor belt

11

conveyor chain

12

Conveyor belt

15a, 15b, 15c

shrink device

16a, 16b, 16c

Exit area

20, 20*

first coolant device/blower

22, 22*

Coolant/cooling air

25

second coolant device

26, 26*

Coolant/cooling air

27, 27*

fan

28

Cooling channel

29

nozzle opening

30

Coolant curtain

40

laterally arranged coolant device

42

Coolant/cooling air

45

sensor

50

steering

Claims (12)

Shrinking device (1, 15a, 15b, 15c, 15d) for shrinking an outer packaging (7) around a collection of articles (6) into a container (5*), the shrinking device having a transport route (10), an entrance area (3), a shrink tunnel (2) and an exit area (4, 16a, 16b, 16c, 16d), articles (6) combined with an outer packaging (7) being subjected to hot air in order to shrink the outer packaging (7), the transport route ( 10) serves for the uninterrupted transport of the containers (5*) through the entrance area (3), the shrink tunnel and the exit area (16a, 16b, 16c) of the shrink device (15a, 15b, 15c), in the exit area (4, 16a, 16b , 16c) at least one first coolant device (20) is arranged above the transport route (10), through which the containers (5*) can be acted upon by a cooling air flow (22) from above, the transport route (10) being a continuous and coolant device permeable means of transport and wherein in the exit area (16a, 16b, 16c, 16d) of the shrinking device (15a, 15b, 15c, 15d) below the means of transport at least one second coolant device (25) is arranged, through which the bottom area of the container (5*) can be acted upon by a cooling air flow (26) from below, wherein directly after the exit of the shrink tunnel at least a first upper coolant device (20*) and a second lower coolant device (27*) are arranged directly opposite one another, which first upper coolant device (20*) produces a largely vertically downward coolant flow and which second lower coolant device (27*) produces a coolant flow directed largely vertically upwards. Shrinkage device (1, 15a, 15b, 15c, 15d). Claim 1 , wherein the means of transport is a conveyor belt (11), an endless conveyor chain, a wire link belt chain, a mesh belt or a bar roller chain. Shrinking device (1, 15a, 15b, 15c, 15d) according to one of Claims 1 until 2 , wherein the coolant (26) is a cooling air stream. Shrinking device (1, 15a, 15b, 15c, 15d) according to one of the preceding claims, wherein the at least one second coolant device (25) is a fan (27), in particular a cross-flow fan, a centrifugal fan or an axial fan. Shrinking device (1, 15a, 15b, 15c, 15d) according to one of Claims 1 until 3 , wherein the at least one second coolant device (25) is a coolant channel (28). Shrinkage device (1, 15a, 15b, 15c, 15d). Claim 5 , wherein the coolant channel (28) has nozzle openings (29) on its upper side. Shrinking device (1, 15a, 15b, 15c, 15d) according to one of Claims 5 until 6 , wherein the coolant channel (28) comprises at least one internal fan for generating the coolant flow or wherein the coolant channel (28) is connected to at least one external fan for generating the coolant flow. Shrinking device (1, 15a, 15b, 15c, 15d) according to one of the preceding claims, wherein at least one first coolant device (20*) arranged above the transport route and at least one second coolant device (27*) arranged below the transport route at the exit of the shrink tunnel (2) a coolant curtain (30) can be generated. Shrinking device (1, 15a, 15b, 15c, 15d) according to one of the preceding claims, wherein the coolant flow (26) and / or the at least one second coolant device (25) in the output region (16a, 16b, 16c, 16d) of the shrinking device (15a , 15b, 15c, 15d) is arranged movably. Shrinkage device (1, 15a, 15b, 15c, 15d). Claim 9 , wherein the movement of the coolant flow (26) and / or the at least one second coolant device (25) can be controlled analogously to the movement of the containers (5*). Shrinking device (1, 15a, 15b, 15c, 15d) according to one of the preceding claims, wherein in the exit area (16a, 16b, 16c, 16d) of the shrinking device (15a, 15b, 15c, 15d) there are coolant devices (20, 25, 40) are arranged. Method for cooling containers (5*) with a device according to one of Claims 1 until 11 , wherein articles (6) are put together, wrapped in an outer packaging (7) and the outer packaging (7) is shrunk onto the articles (6) in a shrink tunnel (2), the containers (5*) being transported via a means of transport (10). and after leaving the shrink tunnel (2) are cooled from above and below, characterized in that at least the bottom area of the container (5*) is supplied with coolant (22, 22*, 26, 26*) from below, whereby the coolant (22, 22*, 26, 26*) is generated by at least one coolant device (25) which is located in an output region (16a, 16b, 16c, 16d) of a shrinking device (15a, 15b, 15c) downstream of the shrink tunnel (2). , 15d) is arranged below the transport means (10).

Images