Patent Application
20230382579
The present invention relates to a longitudinal nozzle arrangement and to the sealing unit of a packaging machine. Moreover, the present invention relates to a sealing station that connects an upper material web to the lower material web, and relates to a method for producing a packaging.
Packaging machines are known from the prior art. In these packaging machines, a material web or packaging tray is filled with a product and this material web/packaging tray is then hermetically sealed with an upper material web in a sealing station. Prior to the sealing, the atmosphere in the packaging is changed with respect to the ambient atmosphere, for example, the pressure in the packaging is reduced and/or a gas differing in composition from air is injected into the packaging. The packaging machine can be a thermoformer or a tray sealer, for example. The substance in the material web may preferably be paper, paperboard, metal, a plastic film, and/or a combination thereof. In the past, changing the atmosphere has frequently resulted in hygiene problems and/or the change in the atmosphere was incomplete and/or undesired folds, wrinkles, or other discrepancies in shape were created on a material web, generally the upper material web, and/or there was increased friction and/or collision when the sealed packaging was transported further, and/or undesired dust was created, in particular during processing of fiber-based material webs, for example during cutting of paperboard.
It was therefore the object of the present invention to provide a longitudinal nozzle arrangement, a sealing unit, a packaging machine, and/or a method that does not suffer from the drawbacks of the prior art.
The object is attained with a longitudinal nozzle arrangement that has a longitudinal extension direction along which a plurality of injection openings and/or evacuation openings are provided and that has a first end and a second end along the longitudinal extension direction, wherein a ramp, the incline of which extends at least in the longitudinal extension direction, is provided on at least one end.
Information provided regarding the subject matter of the present invention also applies equally to the other subject matters, and vice versa. Features of this subject matter of the present invention can be included in other subject matters and vice versa.
This subject matter of the present invention relates to a longitudinal nozzle arrangement with which a gas, in particular air, between two material webs in a sealing station is evacuated or a gas, in particular an inert gas, such as for example N2 and/or Ar, or CO2 or O2 is injected between the material webs. The material webs can be a paper, paperboard, aluminum, and/or plastic film web. The material webs are transported in a packaging machine along a direction of movement, in particular further transported intermittently, in cycles by a so-called draw length or format length, i.e., a certain material web length. A plurality of packaging trays are preferably molded into the lower material web per cycle, or the material web is left unmolded and filled with the product to be packaged, and then in the sealing station is sealed with the upper material web following the gas exchange described in the foregoing. Such a format has at least one gap, wherein a gap preferably has a plurality of packaging trays arranged transverse to the transport direction of the lower material web. Preferably such a format has a plurality of such gaps that are arranged one after the other relative to the transport direction of the lower material web. In addition, a format preferably has a plurality of rows of packaging trays arranged parallel to the transport direction of the lower material web. It is preferably now provided that the longitudinal nozzle arrangement is arranged in the region of at least one lateral edge, preferably both lateral edges, of the material webs, wherein the longitudinal extension direction of the longitudinal nozzle arrangement extends parallel to the movement direction of the material web. The longitudinal nozzle arrangement has a plurality of openings that are preferably provided adjacent to one another, particularly preferably adjacent to one another in a horizontal plane, relative to the longitudinal extension direction of the longitudinal nozzle arrangement or the movement direction of the material web.
The longitudinal nozzle arrangement preferably has a flat nozzle, the horizontal extension of which is greater transverse to the longitudinal extension direction of the longitudinal nozzle arrangement than its perpendicular extension transverse to the longitudinal extension of the longitudinal nozzle arrangement. The flat nozzle preferably has a plurality of openings that are provided adjacent to one another along the longitudinal extension direction of the flat nozzle. The flat nozzle preferably tapers towards the openings. The lower material web and upper material web are preferably each positioned on opposing sides of the flat nozzle, in particular when a gas is evacuated or injected. Alternatively, a nozzle that is wedge-shaped, at least in sections, can be provided instead of the flat nozzle. The lower material web and upper material web are preferably each positioned on opposing sides of the wedge-shaped nozzle, in particular when a gas is evacuated or injected.
The openings of the longitudinal nozzle arrangement can each be employed for injecting gas and/or evacuating gas, in particular air. The gas volume flow can preferably be adjusted per opening or a group of a plurality of openings can preferably be adjusted individually independently of the volume flow of the other nozzles. This may be performed manually or automatically. If one longitudinal nozzle arrangement each is arranged laterally to the right and left of the material web in the movement direction, one longitudinal nozzle arrangement can be employed solely for evacuating a gas and one longitudinal nozzle arrangement can be employed solely for injecting a gas. However, it is also preferred that both longitudinal nozzle arrangement are employed for injecting gas into and/or evacuating gas from the packaging.
The length of the longitudinal nozzle arrangement, in particular the flat nozzle, in the longitudinal extension direction preferably essentially corresponds to the straight format produced or the draw length during one cycle. According to one further preferred embodiment, the length of the longitudinal nozzle arrangement, in particular the flat nozzle or wedge-shaped nozzle, in the longitudinal extension direction essentially corresponds to the maximum possible draw length of the material web in one cycle. If the current draw length or the current format is shorter than the maximum possible draw length or the maximum format length, for example, if, instead of the maximum number n gaps, the current draw length or the current format includes only a number n−1 gaps, openings are preferably turned off at one or both end regions of the flat nozzle.
The gas flow in the longitudinal nozzle arrangement is preferably regulatable during gas evacuation and/or injection. This preferably applies to the gas volume flow and/or to the amount of gas. The openings of a longitudinal nozzle arrangement via which gas is introduced and/or evacuated are preferably selectable, individually or as a group of a plurality of nozzles. The gas flow is adjusted and/or the openings are selected preferably via at least one valve, preferably a plurality of valves, preferably provided in the longitudinal nozzle arrangement. The valves are preferably adjusted automatically when there is a production change.
The longitudinal nozzle arrangement preferably has two channels, one for evacuating gas, i.e. for evacuating the packaging, and one for injecting a gas, i.e., supplying gas to the packaging. Both channels can preferably be connected selectively to the openings so that each opening can be employed as desired for evacuating gas and for supplying gas.
The longitudinal nozzle arrangements acts in a particularly advantageous and gentle manner with fiber-based/fiber-containing material webs that contain, for example, components of paper, corrugated cardboard, or paperboard, because the gas is exchanged using the longitudinal nozzle and the gas is not conducted through the material web, as is otherwise conventional, for example through so-called lateral perforation, so that there is no cutting of holes for the lateral perforation in the paperboard, for example, which generates dust, so that less dust, or no dust at all, can make its way into the packaging, and/or cleaning efforts, for example for the tools, can be reduced.
According to the invention, the longitudinal nozzle arrangement, in particular the flat nozzles or wedge-shaped nozzles, have a first, front end and a second, rear end relative to their longitudinal extension direction or the transport direction of the material web. According to the invention, a ramp, the incline of which extends at least in the longitudinal extension direction, is provided on at least one of the two ends. The ramp is preferably provided at the end(s) of the flat nozzle. The longitudinal nozzle arrangement, in particular the flat nozzle, preferably tapers towards the end of the longitudinal nozzle arrangement, in particular the flat nozzle or wedge-shaped nozzle, to achieve, for example, a smooth approximation of the level of the longitudinal nozzle arrangement, especially at the level of the upper tool, so that the tendency to form wrinkles and folds in the material webs is significantly reduced.
The person skilled in the art understands that the incline of the ramp does not have to be linear, but rather may also be curved. A linear incline is preferred, however.
Preferably, on at least one of the two ends at which a ramp is provided, a second ramp is provided, the incline of which preferably extends transverse to the longitudinal extension direction and is preferably overlaid on the first ramp, the incline of which extends in the longitudinal extension direction. The inclines of the two ramps are preferably the same or similar, but may also be at different angles. The inclines of each ramp can be embodied the same across the length of the ramp or different, for example by segment and/or as radii, for example crowned. It is particularly advantageous that a possible edge created at the transition of the two ramps is rounded. Two such ramps form a ramp arrangement.
At least one ramp or ramp arrangement is preferably provided in the region between the front and rear end of the longitudinal nozzle arrangement and/or the flat nozzle and/or the wedge-shaped nozzle, for example in a shorter format having, for example, only n−1 gaps, and the incline of which extends in and preferably also transverse to the longitudinal extension direction. This ramp particularly preferably is opposed by a second ramp in the longitudinal direction, both ramps preferably being spaced apart from one another by a preferably straight segment or no distance being provided, and preferably their tapered ramp ends opposing one another. This second ramp arrangement is disposed in a shorter format outside the format region, that is behind or in front of it, but for example after a subsequent tool change to a format with maximum length, the second ramp is disposed within the format region, just like the first ramp opposing it.
The longitudinal nozzle arrangement, in particular the flat nozzle or wedge-shaped nozzle, has at one end, in particular the front, upstream end, a tongue that preferably extends transverse to the longitudinal extension direction of the nozzle arrangement or flat nozzle. The tongue is preferably exchangeable and/or made of a different material than the rest of the longitudinal nozzle arrangement. The tongue is preferably made of a plastic, particularly preferably an elastic plastic. One possible plastic material is rubber or silicone, for example. The tongue and the rest of the longitudinal nozzle arrangement may also comprise the same material, however, for example aluminum or plastic.
The longitudinal nozzle arrangement is preferably produced, at least in part, by means of layer-wise material application.
On its surfaces, in particular on its bottom side, the flat nozzle has an indentation into which the transport means of the packaging machine can move, in particular the grippers on the chain members.
A further subject matter of the present invention is a sealing unit having a longitudinal extension direction with a first end and a second end, wherein provided on at least one end is a ramp, the incline of which extends in the longitudinal extension direction.
Information provided regarding this subject matter of the present invention also applies equally to the other subject matters, and vice versa. Features of this subject matter of the present invention can be included in other subject matters and vice versa.
According to the invention, the sealing unit has a first, front end and a second, rear end relative to its longitudinal extension direction or the transport direction of the material web. According to the invention, a ramp is provided on at least one of the two ends and its incline extends in the longitudinal extension direction. The sealing unit preferably tapers away from the end of the sealing unit. Preferably, at the at least one of the two ends at which a ramp is provided, a second ramp is provided, the incline of which preferably extends transverse to the longitudinal extension direction and overlays the first ramp, the incline of which extends in the longitudinal extension direction.
At one end, the sealing unit preferably has a ramp that preferably extends transverse to the longitudinal extension direction.
The sealing unit is preferably made of a rubber-like elastic material, for example silicone, and is preferably produced by injection or injection molding.
The sealing unit is preferably provided as a closed structure, i.e., is continuous. The sealing unit is preferably molded or injection molded.
A further subject matter of the present invention is a packaging machine in which, for producing a packaging, a material web is transported along a movement direction and which has a sealing station that connects the material web to an upper material web, wherein the sealing station has the inventive longitudinal nozzle arrangement and/or the inventive sealing unit.
Information provided regarding this subject matter of the present invention also applies equally to the other subject matters, and vice versa. Features of this subject matter of the present invention can be included in other subject matters and vice versa.
This subject matter of the present invention relates to a packaging machine for producing a packaging in which a lower material web, for example a cardboard or paper web, a plastic film, or a material web that in particular has a paperboard, paper, aluminum, or other layer apart from plastic, is rolled off a supply roller and transported, preferably intermittently/in cycles, along the packaging machine in a transport plane. In a molding station this lower film web can then first be molded by means of a thermoforming tool in order to mold, for example, a depression and/or a structure, in particular an anti-slip structure, in the lower material web. As a rule, the molding station has a lower tool and an upper tool that for molding are moved towards one another and for further transport of the lower material web are moved away from one another. The lower tool is disposed below the transport plane for the lower material web and the upper tool is disposed above the transport plane for the lower material web. In the inventive packaging machine, as a rule a plurality of packagings that are arranged in a so-called format are processed simultaneously and then transported simultaneously along the packaging machine. Before and/or during thermoforming, the lower material web is preferably heated with a heating plate. Then the lower material web is filled with a product, in particular a food, such as, for instance, lunch meat, ham, or cheese, and in a next step in a sealing station is sealed with an upper film, wherein as a rule the upper film is sealed to the lower film web. Then the packaging produced in this manner is separated in that the packaging is cut from the lower material web and upper material web. The upper material web is also rolled off of a supply roller. A dancer that keeps the tension in the specific material web at least essentially constant is preferably disposed downstream of at least one supply roller relative to the transport direction of the specific film web. The dancer can be a linear dancer or a rotational dancer.
The packaging can also involve a so-called tray sealer, however, in which the pre-produced packaging shells are filled with a product and then sealed with an upper film.
According to the invention, the sealing station has the inventive longitudinal nozzle arrangement and/or the inventive sealing unit that produces the changed atmosphere, relative to the environment, in the packaging. The pressure in the packaging and/or in the composition of the atmosphere can be changed compared to air. The person skilled in the art is familiar with evacuating and/or supplying gas. The packaging can be evacuated prior to being supplied with gas in order to improve the gas supplying process.
During sealing, the level approximation of the longitudinal nozzle arrangement described above, in particular of its flat nozzle or wedge-shaped nozzle, permits a sharp reduction in, or even complete elimination of, the formation of folds and wrinkles in the material webs, significant improvement in the sealing effect, hygiene, and completeness of the gas exchange. In addition, in particular during further transport of the finished sealed packaging, the risk of the packaging colliding with the longitudinal nozzle arrangement is avoided.
Particularly preferred is a sealing station in which the inventive longitudinal nozzle arrangement develops the sealing effect without it being necessary to use an additional sealing unit made of a rubber-like elastic material.
The inventive longitudinal nozzle arrangement, in particular its flat nozzle or wedge-shaped nozzle, is arranged for evacuating and/or supplying gas between the two material webs. The sealing unit is disposed above the upper material web and presses the latter in a sealing manner against the longitudinal nozzle arrangement during the evacuation or supplying of gas. The lower material web can also be pressed in a sealing manner against the longitudinal nozzle arrangement by means of the lower tool during the evacuation or supplying of gas.
The sealing station of the packaging machine preferably has a lower tool and an upper tool, wherein the lower tool and/or the upper tool are preferably provided to be raisable and lowerable. The upper tool is disposed above the upper material web and the lower tool is disposed below the lower material web. For further transport of the material webs, the upper tool is preferably raised and the lower tool is preferably lowered, so that each has no contact, or reduced contact, with the corresponding material web, so that friction is sharply reduced.
The sealing unit is preferably connected to the upper tool and is raised and lowered therewith. The sealing unit preferably has a spring inserted into a groove in the upper tool, thus reversibly connecting the sealing unit to the upper tool. When lowered, the upper tool presses the sealing unit against the upper material web and the latter against the longitudinal nozzle arrangement, especially the flat nozzle. In this way the sealing unit can reversibly elastically deform.
The longitudinal nozzle arrangement is preferably connected directly or indirectly to a frame of the packaging machine, i.e., is preferably provided location-fast.
A further subject-matter of the present invention is a method for sealing an upper material web to a material web for producing a packaging, wherein by means of a longitudinal nozzle arrangement the atmosphere in the packaging is changed compared to the environment, wherein a sealing unit is positioned against the material web when the atmosphere is changed, and the material webs are further transported following the sealing, and wherein the sealing unit can preferably be raised prior to and/or during the further transport.
Information provided regarding the subject matter of the present invention also applies equally to the other subject matters, and vice versa. Features of this subject matter of the present invention can be included in other subject matters and vice versa.
According to this subject-matter of the present invention, the sealing unit is raised prior to and/or during further transport of the material web. Because of this, there is no contact, or reduced contact, between the upper material web and the sealing unit during the further transport of the material web, in particular the upper material web, so that friction is at least reduced. Once transport of the material web has ended after a cycle, the sealing unit is lowered again and pressed against the upper material web. The sealing unit is preferably lowered prior to and/or during the change in the atmosphere and pressed against the upper material web.
An inventive longitudinal nozzle arrangement and/or the inventive sealing unit are preferably used for changing the atmosphere.
During the changing of the atmosphere, the sealing unit is preferably pressed against the longitudinal nozzle, in particular the ramp of the sealing unit is pressed against the outlet ramp of the longitudinal nozzle arrangement, in particular the flat nozzle.
One further subject-matter of the present invention is a method for sealing an upper material web to a material web for producing a packaging, wherein the atmosphere is changed compared to the environment by means of a longitudinal nozzle arrangement, wherein a sealing unit is positioned against the material web during the changing of the atmosphere and the material webs are further transported following the sealing, in which the longitudinal nozzle arrangement develops the sealing effect without it being necessary to use an additional sealing unit made of a rubber-like elastic material.
Information provided regarding the subject matter of the present invention also applies equally to the other subject matters, and vice versa. Features of this subject matter of the present invention can be included in other subject matters and vice versa.
This preferred or inventive embodiment of the present invention has the advantage that the required sealing effect is obtained using the longitudinal nozzle in conjunction with the material web.
The following information applies for all embodiments of the present invention.
The gas flow entering the sealing tool or evacuated from the sealing tool using the injection openings and/or evacuation openings is adjustable, in particular individually adjustable. This adjustment can be made manually or by motor. The goal of the adjustment is preferably that the gas volume flow rate when injecting and/or evacuating gas is at least essentially equal in all openings.
The openings from which gas outlets or through which gas is evacuated, and the gas lines connected thereto, in particular those provided in the longitudinal nozzle, are preferably separate from one another. This results in advantages in hygiene.
Preferably a valve is provided both in the gas line to which the injection openings are connected and the gas line to which the evacuation openings are connected, and each said valve can be used in particular to open and close the respective line. Each valve is preferably spaced apart from the openings to which it is connected.
When evacuating gas from the sealing tool, a negative pressure is also applied to the gas volume in the injection line, disposed between the valve and the openings. The resulting gas flow draws any impurities present out of the injection line, so that the latter is cleaned. When the gas is injected into the sealing tool, the gas volume in the evacuation line between the opening and the valve is compressed, so that impurities possibly present therein are moved away from the evacuation opening and pressed into the line and thus do not travel into the packaging to be produced.
The invention is explained in the following using
The longitudinal nozzle arrangement has a longitudinal extension direction 27 extending at least essentially parallel to the transport direction 20. Provided along this longitudinal extension direction 27 is a nozzle 26 having a plurality of openings 21, arranged adjacent to one another here. The openings 21 can be employed selectively for evacuating air from one or more packagings and/or for injecting an inert gas. For this, the longitudinal nozzle arrangement has one or more valves. With this/these or with one or a plurality of other valves, the gas volume flow can also be adjusted when gas is evacuated and/or injected and/or the gas quantity is adjusted. All or some of the valves can be adjusted manually or automatically. The length of the longitudinal nozzle arrangement in the longitudinal extension direction can essentially equal the draw length of the format currently being produced. However, it is also possible to provide a longer longitudinal nozzle arrangement length and to shut off openings in the inlet region 28 and/or in the outlet region 29 by means of the valve(s). In the present case, the nozzle 26 is embodied as a flat nozzle, i.e., its horizontal extension transverse to the longitudinal extension direction 27 is greater, preferably substantially greater, than its vertical extension transverse to the longitudinal extension direction 27. In the present case the flat nozzle tapers in the direction of the openings. When a gas is evacuated from and/or injected into the format of packagings, the flat nozzle extends between the upper material web 14 and the material web 8, wherein the material web 8 relative to the vertical contacts the flat nozzle from below and the material web 14 contacts the flat nozzle from above.
For evacuating and or supplying gas, the openings 21 can preferably be controlled individually, particularly preferably by group. If there are two longitudinal nozzle arrangements 10, one to the right and one to the left of the material web, one longitudinal nozzle arrangement can solely evacuate gas and one nozzle arrangement can solely draw off gas.
As can be seen in particular in
The person skilled in the art will recognize that the tongue 22 can also be replaced by a ramp 24, the height of which increases in the running direction relative to the material web until it has reached the height of the flat nozzle.
In the packaging machine, the longitudinal nozzle arrangement 10 is preferably connected to the frame of the packaging machine, specifically preferably such that the flat nozzle 26 is disposed above the transport means, in particular the chain with the grippers. For this, the flat nozzle is preferably embodied concave on its underside, at least in sections, so that the grippers partially project into this concavity.
Also depicted in
If the longitudinal nozzle arrangement also has a ramp in the inlet region, this region of the sealing unit is embodied analogous to the incline 25.
As shown by the double arrow in
The sealing unit 19 is preferably embodied as a closed form, in particular as a closed rectangle or square, that extends around a packaging or a format of packagings.
The inventive method is carried out as follows. One packaging or one material web 8 having one or a plurality of packaging trays is introduced into the sealing station, for example using cyclic transport of the material web 8. The packaging or the material web 8 is then disposed below the flat nozzle 26 and above the lower tool 11. The upper material web 14 that is sealed to the packaging or material web 8 is disposed above the flat nozzle 26. Then the sealing unit 19 is lowered and presses the upper material web against the flat nozzle 26 or against the lower tool 11. Preferably simultaneously the lower tool 11 is raised and presses the material web 8 against the flat nozzle 26 or against the sealing unit 19. Because of this, a closed at least essentially gas-tight region that can now be evacuated or supplied with gas by means of one or a plurality of longitudinal nozzle arrangements 10 is created between the packaging and the upper material web or between the two material webs 8, 14. As soon as the atmosphere in the packaging has been changed, the upper material web 14 is sealed to the lower material web 8. Then the sealing unit 19 is raised again and the lower tool 11 is lowered and at the same time and/or thereafter the packaging or material webs 8, 14 are further transported.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2020 213 308.5 | Oct 2020 | DE | national |
This application is a US national stage of PCT/EP2021/078779 filed on Oct. 18, 2021, which claims priority to DE 10 2020 213 308.5 filed on Oct. 21, 2020, all of which are hereby incorporated by reference herein for all purposes.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/078779 | 10/18/2021 | WO |
