DE102022110134A1 - METHOD FOR PACKAGING PRODUCTS AND CLOSING STATION FOR PACKAGING - Google Patents

Abstract

A lower packaging part (5) is positioned on a receptacle (27) of a closing tool lower part (15). A cover film (19) is positioned between the lower part of the closing tool (15) and an upper part of the closing tool (13) with a shaped body (29). The cover film (19) is sucked upwards into a mold space (33), which is defined by an inner wall (31) of the molded body (29), so that the cover film (19) rests against the inner wall (31). Openings are provided in the inner wall (31), which open into the mold space (33), the openings comprising a first group (35) of openings and a second group (37) of openings. When the cover film (19) is sucked in, the molding space (33) is subjected to a negative pressure (55) via the first group (35) of openings, at least for the duration of a first time window (502). At least for the duration of the first time window (502), the mold space (33) is not subjected to negative pressure via the second group (37) of openings. When the cover film (19) is sucked in, the molding space (33) is subjected to a negative pressure (55) via the first group (35) of openings and via the second group (37) of openings, at least for the duration of a third time window (504).

Description

The present invention relates to the packaging of products in a closing station with a lower part of the closing tool and an upper part of the closing tool.

From the DE 10 2018 218 382 A1 a packaging machine in the form of a tray sealing machine with a sealing station for sealing trays with a skin film is known. The sealing station includes an upper sealing tool part with a dome sealing tool. In an evacuation process, the atmosphere is evacuated from the space above the skin film and below a dome of the dome sealing tool using a vacuum generator. The skin film is stretched or deep-drawn and, at the beginning of this process, lies against a transition area between a sealing surface of the dome sealing tool and an inner dome surface. The dome sealing tool has several heating elements to heat the dome sealing tool on both the sealing surface and the dome surface. A holding element is provided in the transition area, which is preferably designed to be heat-insulating, so that the skin film is not heated or is heated to a lesser extent upon first contact with the dome sealing tool in the transition area. This should have the positive effect that the skin film can stretch more evenly during the evacuation process and the formation of cracks is minimized. A further positive effect of the holding element is said to be the adhesion of the skin film to the holding element, which should result in the expansion in this area being less and the formation of wrinkles during a sealing process being able to be reduced or prevented.

According to one aspect of the invention, a method of packaging products is provided. A lower packaging part is positioned on a holder of a closing tool lower part. A cover film is positioned between the lower part of the closing tool and an upper part of the closing tool. The upper part of the closing tool comprises a molded body. An inner wall of the molded body defines a mold space. The cover film is sucked upwards into the mold space so that the cover film lies against the inner wall. Openings are provided in the inner wall. The openings open into the mold space. The openings include a first group of openings and a second group of openings. When the cover film is sucked in, the mold space is subjected to a negative pressure via the first group of openings, at least for the duration of a first time window. At least for the duration of the first time window, the mold space is not subjected to negative pressure via the second group of openings. When the cover film is sucked in, the mold space is subjected to a negative pressure via the first group of openings and via the second group of openings, at least for the duration of a third time window.

The cover film can be drawn to the first group of openings by the negative pressure during the first time window. During the first time window, the cover film can be deformed by the negative pressure in the direction of the first group of openings. During the first time window, the cover film can lie against the inner wall due to the negative pressure in the area of the first group of openings. The cover film can be held on the inner wall during the first time window by the negative pressure in the area of the first group of openings.

Since negative pressure is not applied to the mold space via the second group of openings, at least for the duration of the first time window, the cover film can be spaced from the inner wall in the area of the second group of openings, at least for the duration of the first time window. Preferably, the cover film is not held on the inner wall of the mold space in the area of the second group of openings, at least for the duration of the first time window. Because there is no negative pressure applied to the mold space via the second group of openings during the first time window, damage to the cover film when the cover film is sucked in can be avoided or reduced.

If during the third time window the molding space is subjected to a negative pressure both via the first group of openings and via the second group of openings, the cover film can be applied to the area both in the area of the first group of openings and in the area of the second group of openings inner wall can be sucked in. During at least part of the third time window, the cover film can be held on the inner wall by the negative pressure both in the area of the first group of openings and in the area of the second group of openings. Preferably, during the third time window, the cover film is completely applied to the inner wall by the negative pressure.

The third time window preferably lies after the first time window. During the first time window, the cover film can initially only be sucked in through the first group of openings in the direction of the inner wall and thus preformed. During the third time window, the preformed cover film can be completely sucked onto the inner wall via the first group of openings and the second group of openings. Through The multi-stage nature of the suction process allows the process of deformation of the cover film to be controlled more precisely. In particular, the cover film can be sucked particularly gently onto the inner wall. Point loads that would lead to tearing of the cover film or to a locally greatly reduced thickness of the cover film can be avoided or reduced.

The shaped body can be heated. The cover film can be heated by sucking the cover film onto the heated molding. Heating the cover film can simplify subsequent connection of the cover film to the lower packaging part. Heating the cover film can simplify subsequent shaping of the cover film, for example for placing it on a product located in or on the lower part of the packaging.

The mold space can be connected to an ambient pressure level via the second group of openings, at least for the duration of the first time window. The ambient pressure level may be an atmospheric pressure level. The ambient pressure level can, for example, be in a range between 80 kPa (0.8 bar) and 120 kPa (1.2 bar), or in a range between 90 kPa (0.9 bar) and 110 kPa (1.1 bar), or in a range between 95 kPa (0.95 bar) and 105 kPa (1.05 bar).

During the first time window, there may be a gas flow, in particular an air flow, through the second group of openings into the mold space. During the first time window, a gas, in particular air, can flow into the mold space through the second group of openings. During the first time window, a gas flow, in particular an air flow, can be present within the mold space from the second group of openings to the first group of openings. The air flow can run at least partially along the inner wall of the mold space. The air flow can prevent contact between the cover film and the inner wall of the mold space, at least in some areas. The air flow can space the inner wall and the cover film from one another at least in certain areas. By preventing contact between the cover film and the inner wall at least in some areas, heat transfer from the inner wall to the cover film can be reduced at least in some areas. The air flow can prevent or reduce uneven heating of the cover film due to area-wise contact of the cover film with the inner wall. Uneven heating of the cover film could lead to weak points in the cover film, particularly in higher temperature areas. Gas flowing through the second group of openings can absorb heat from the shaped body and at least partially release it to the cover film. The subsequent gas flow can contribute to gentle heating of the cover film.

The mold space can be subjected to a negative pressure via the first group of openings at least for the duration of a second time window lying between the first time window and the third time window. In particular, the mold space can be continuously subjected to a negative pressure via the first group of openings over a period of time comprising the first time window, the second time window and the third time window. However, it would also be conceivable that the mold space, for example between the first time window and the second time window and / or between the second time window and the third time window, is not subjected to negative pressure. A connection of the mold space to the outside via the second group of openings can be closed at least for the duration of the second time window. Closing the connection of the mold space to the outside via the second group of openings can prevent gas, in particular air, from flowing through the second group of openings into the mold space. If no gas can flow into the mold space through the second group of openings, reducing the pressure within the mold space via the first group of openings is made easier. During the second time window, the cover film can be moved and/or reshaped further towards the inner wall.

The second time window can follow the first time window directly or at a time interval. The third time window can follow the second time window directly or at a time interval. The second time window is optional. The third time window can follow the first time window directly or at a time interval.

The first group of openings can be formed in an at least substantially horizontal region of the inner wall. The first group of openings can be formed in a ceiling area of the mold space. The first group of openings may be provided in the upper 50%, or in the upper 40%, or in the upper 30%, or in the upper 20%, or in the upper 10%, or in the upper 5% of a height of the mold space. A negative pressure applied through the first group of openings can pull the cover film upwards into the mold space.

The second group of openings can be formed in an at least substantially vertical region of the inner wall. The second group of openings can be formed in a side wall of the molded body, which is part of the inner wall. The second group of openings may be in the lower 70%, or in the lower 60%, or in the lower 50%, or in the lower 40%, or in the lower 30%, or in the lower 20%, or in the lower 10% of a height of the mold space be provided. If no negative pressure is applied through the second group of openings in a lower region of the mold space during the first time window, a tendency of the cover film to rest against the inner wall in the lower region of the mold space can be reduced. In particular, the risk of the cover film being excessively heated in the lower region of the mold space due to contact with the inner wall can be reduced. A reduction in the thickness of the cover film by stretching the cover film in contact with the inner wall in the lower region of the mold space can also be reduced.

A connection of the mold space to the outside via the second group of openings can be closed at least for the duration of the first time window. A closed connection of the mold space to the outside via the second group of openings can increase a tendency of the cover film to initially come into contact with the inner wall in the area of the first group of openings due to the negative pressure applied via the first group of openings.

During the first time window, the cover film can be sucked onto the inner wall in the area of the first group of openings, but not in the area of the second group of openings. In particular, during the first time window, the cover film can rest against the inner wall in the area of the first group of openings and be held on the inner wall by the negative pressure. Areas of the cover film that were already applied to the inner wall in the first time window and are held on the inner wall by negative pressure applied via the first group of openings can be at least partially protected from being excessively stretched and thus thinned out during the third time window.

The first group of openings can be formed in an at least substantially vertical region of the inner wall. The first group of openings can be formed in a side wall of the molded body, which is part of the inner wall. The first group of openings may be in the lower 70%, or in the lower 60%, or in the lower 50%, or in the lower 40%, or in the lower 30%, or in the lower 20%, or in the lower 10% of a height of the mold space be provided. If the cover film is sucked onto the inner wall in a lower region of the mold space in the first time window, the cover film can be held in place by the negative pressure in the lower region of the mold space and protected from excessive stretching, at least to a certain extent, even if in the third time window Negative pressure is applied via the second group of openings.

The second group of openings can be formed in an at least substantially horizontal region of the inner wall. The second group of openings can be formed in a ceiling area of the mold space. The second group of openings may be provided in the upper 50%, or in the upper 40%, or in the upper 30%, or in the upper 20%, or in the upper 10%, or in the upper 5% of a height of the mold space. If the cover film is not sucked in during the first time window in an upper region of the molding space, the cover film can be placed against the inner wall in the lower region of the molding space.

According to a further aspect of the invention, a closing station for packaging is provided. The closing station includes a lower part of the closing tool, an upper part of the closing tool and a pressure regulation system. The lower part of the closing tool includes a receptacle for a lower part of the packaging. The upper part of the closing tool comprises at least one shaped body. The shaped body has an inner wall. The inner wall defines a mold space that is open at the bottom. The pressure regulation system includes at least one negative pressure source. The negative pressure source includes at least a first valve arrangement and a second valve arrangement. Openings are provided in the inner wall. The openings open into the mold space. The openings include a first group of openings and a second group of openings. The first valve arrangement is configured to connect the mold space to the at least one vacuum source via the first group of openings. The first valve arrangement is configured to prevent connection of the mold space to the at least one vacuum source via the first group of openings. The second valve arrangement is configured to connect the mold space via the second group of openings of the at least one vacuum source. The second valve arrangement is configured to prevent connection of the mold space to the at least one vacuum source via the second group of openings.

By providing the first valve arrangement and the second valve arrangement, the first group of openings and the second group of openings can be switched differently. For example, at a certain point in time only one of the two groups of openings can be connected to the at least one vacuum source be, while the other group of openings is not connected to the at least one vacuum source. By providing the first valve arrangement and the second valve arrangement, the pressure conditions in the area of the first group of openings and in the area of the second group of openings can be controlled differently. In particular, a process with a predefined sequence of pressure changes in different areas of the mold space can be implemented.

The at least one negative pressure source can include exactly one negative pressure source. The first valve assembly and the second valve assembly may be configured to connect the first group of ports and the second group of ports to the same vacuum source. The at least one negative pressure source can include several negative pressure sources, for example two or more than two negative pressure sources. The at least one vacuum source may include a first vacuum source and a second vacuum source. The first valve arrangement may be configured to connect the mold space to the first vacuum source via the first group of openings. The first valve arrangement may be configured to prevent connection of the mold space to the first vacuum source via the first group of openings. The second valve arrangement may be configured to connect the mold space to the second vacuum source via the second group of openings. The second valve arrangement may be configured to prevent connection of the mold space to the second vacuum source via the second group of openings. The at least one negative pressure source can comprise at least one vacuum pump.

The first group of openings can be provided in the upper 30% of a height of the mold space. The second group of openings can be provided in the lower 50% of a height of the mold space.

The first group of openings can be provided in the lower 50% of a height of the mold space. The second group of openings can be provided in the upper 30% of a height of the mold space.

The first valve assembly may be configured to connect the mold space to an ambient pressure level via the first group of openings. The second valve assembly may be configured to connect the mold space to an ambient pressure level via the second group of openings. The first valve assembly may be configured to connect the mold space to an ambient pressure level via the first group of openings and the second valve assembly may be configured to connect the mold space to the ambient pressure level via the second group of openings.

The pressure regulation system can be configured to connect the mold space to the at least one negative pressure source via the first group of openings, at least for the duration of a first time window. The pressure regulation system can be configured to prevent a connection of the mold space to the at least one negative pressure source via the second group of openings at least for the duration of the first time window.

The pressure regulation system may be configured to connect the mold space to an ambient pressure level via the second group of openings for at least the duration of the first time window.

The pressure regulation system can be configured to prevent connection of the mold space to the outside via the second group of openings at least for the duration of the first time window.

The closing station can include a control. The controller can control the pressure regulation system. The controller can control the first valve system and the second valve system.

The sealing tool base and the sealing tool top may be configured to cooperate to connect the packaging base and the cover film. The upper part of the closing tool can be arranged above the lower part of the closing tool. The upper part of the closing tool and the lower part of the closing tool, or at least parts thereof, can be configured to carry out a relative movement directed towards one another.

The mold space can be connected to an ambient pressure level via both the first group of openings and the second group of openings, at least for the duration of a fourth time window. In the fourth time window, the cover film can collapse downwards away from the inner wall due to a loss of negative pressure sucking the cover film onto the inner wall, in particular if an area below the cover film is or has been evacuated. The cover film can thus rest on the lower packaging part and/or a product located on it. The cover film can be connected to the lower packaging part by placing the cover film on the lower packaging part. Optionally, the cover can also be sealed be done on the bottom part of the packaging. The fourth time window can be later than the third time window. The fourth time window can follow the third time window directly or at a time interval.

The invention also relates to a packaging machine with the closing station described. The packaging machine can in particular be designed as a thermoforming packaging machine or as a tray sealer.

The terms “first time window,” “second time window,” “third time window,” and “fourth time window” are used to facilitate description of the invention. The time windows preferably follow one another in the order in which they are named. However, not all time windows have to be implemented. For example, only the first time window and the third time window could be implemented, or the first time window, the third time window and the fourth time window, or the first time window, the second time window, the third time window and the fourth time window. In particular, the existence of the third time window or the fourth time window does not imply the existence of the second time window. However, the second time window can definitely be implemented together with the third and/or fourth time window.

• 1 zeigt eine schematische Perspektivansicht einer Verpackungsmaschine mit einer Verschließstation gemäß einer Ausführungsform.
• 2 zeigt eine schematische Schnittansicht einer Verschließstation gemäß einer Ausführungsform.

The invention is further explained below using exemplary embodiments with reference to the figures.

• 1 shows a schematic perspective view of a packaging machine with a closing station according to one embodiment.
• 2 shows a schematic sectional view of a closing station according to an embodiment.

The 3A until 3D show a sequence of the function of a pressure regulation system of the closing station according to one embodiment.

4 shows in the graph 100 a time course of a pressure connected via upper openings to a mold space of the upper part of the closing tool of a closing station according to an embodiment and in part 200 a time course of a pressure connected to the mold space via lower openings.

The 5A until 5C show a sequence of the function of a pressure regulation system of the closing station according to one embodiment.

6 shows in the graph 100 a time course of a pressure connected via upper openings to a mold space of the upper part of the closing tool of a closing station according to an embodiment and in part 200 a time course of a pressure connected to the mold space via lower openings.

1 shows a schematic perspective view of a packaging machine 1 according to one embodiment. In the embodiment shown, the packaging machine 1 is designed as a tray sealing machine. However, the invention can also be applied to other packaging machines, for example thermoforming packaging machines.

The packaging machine 1 includes a closing station 3 for closing packaging bases 5, each of which carries a product to be packaged. In the embodiment shown, the packaging bases 5 are designed as trays in which the products to be packaged are received. The packaging machine 1 comprises a feed device 7 for feeding the lower packaging parts 5 filled with product to the closing station 3 and a discharge device 9 for transporting the closed packaging away from the closing station 3. The lower packaging parts 5 pass through the packaging machine 1 along a production direction 11.

2 shows a schematic sectional view of the closing station 3, the cutting plane being perpendicular to the production direction 11. The closing station 3 comprises an upper closing tool part 13 and a lower closing tool part 15. The upper closing tool part 13 and the lower closing tool part 15 are movable relative to one another along a vertical direction 17. The upper closing tool part 13 and the lower closing tool part 15 work together during operation to connect the lower packaging parts 5 with a cover film 19 and thus to package the products between the lower packaging parts 5 and the cover film 19, in particular to pack them airtight. To close the lower packaging parts 5, the upper closing tool part 13 and the lower closing tool part 15 are moved towards each other until the cover film 19 is clamped between an upper tool cover 21 of the upper closing tool part 13 and a lower tool cover 23 of the lower closing tool part 15. Preferably, a working space 25 defined by the upper tool casing 21 and by the lower tool casing 23 is then sealed to the outside in an at least essentially gas-tight manner.

The closing tool lower part 15 includes a receptacle 27 for the packaging lower parts 5. The closing tool upper part 13 comprises shaped bodies 29. In the embodiment shown, several lower packaging parts 5 can be closed per work cycle. Alternatively, for example, only one lower packaging part 5 could be closed per work cycle.

In the embodiment shown, the receptacle 27 is provided as a common receptacle for all lower packaging parts 5 to be closed during a work cycle. Alternatively, separate receptacles could be provided for one or more lower packaging parts 5 to be closed during a work cycle. In the embodiment shown, a shaped body 29 is provided for each lower packaging part 5 to be closed during a work cycle. Alternatively, all or some of the molded bodies 29 could be firmly connected to one another and/or formed in one piece.

The molded bodies 29 each have an inner wall 31, which each defines a mold space 33 that is open at the bottom.

The shaped bodies 29 are heated, for example, by heating elements 35 provided in the shaped bodies 29. The heating elements 35 can be designed, for example, as electrical resistance heating elements. The shaped bodies 29 are preferably heated in such a way that the inner wall 31 of the shaped body 29 each has a temperature that is as uniform as possible.

The general procedure for closing the lower packaging parts 5 in the closing station 3 is that the closing station 3 is first brought into a working position by moving the upper closing tool part 13 and the lower closing tool part 15 relative to one another along the vertical direction 17, so that the workspace 25 is closed. Here, an area of the cover film 19 lies between the upper part of the closing tool 13 and the lower part of the closing tool 15 and is clamped between them. The cover film 19 is then pulled upwards into the molded bodies 29 by means of a vacuum, so that the cover film 19 rests against the inner walls 31 of the molded bodies 29. The cover film 19 is heated by surface contact with the heated moldings 29. This makes the cover film 19 more easily deformable and easier to connect to the lower packaging parts 5. The receptacle 27 and the shaped bodies 29 are moved relative to one another along the vertical direction 17. Subsequently, an area of the working space 25 lying under the cover film 19 is evacuated at least to a certain extent. After evacuating the area of the working space 25 lying under the cover film 19, the suction of the cover film 19 onto the inner walls 31 of the molded bodies 29 is stopped and areas between the cover film 19 and the inner walls 31 of the molded bodies 29 are gassed again. Due to the vacuum underneath the cover film 19, the cover film 19 collapses downwards and lies against the packaging base parts 5 and the products lying thereon. The cover film 19 can already be connected to the lower packaging parts 5, so that the products are sealed airtight between the lower packaging parts 5 and the cover film 19. Optionally, for example by the interaction of a sealing surface 37 of a molded body 29 and a corresponding sealing surface 39 of the receptacle 27, the cover film 19 can be sealed to the lower packaging part 5 along a circumferential sealing seam.

The drawing of the cover film 19 into the mold space 33 is described below according to two different embodiments, both of which are gentle on the cover film 19. The first embodiment is based on 3A until 3D and 4 described. The second embodiment is based on 5A until 5C and 6 described. Both embodiments are in the system 1 and 2 applicable.

3A shows a schematic sectional view through a molded body 29 of the closing station 3 according to the first embodiment. Openings are provided in the inner wall 31, which open into the mold space 33. The openings include a first group 35 of openings and a second group 37 of openings. The first group 35 of openings is provided in a ceiling area of the mold space 33, which is formed by a substantially horizontal section of the inner wall 31. The second group 37 of openings is provided in a lower region of the mold space 33, which is formed by a substantially vertical portion of the inner wall 31 or a side wall portion of the inner wall 31. The first group 35 of openings is connected to a first connecting channel 39. The second group 37 of openings is connected to a second connecting channel 41. A pressure regulating system 43 is provided, which can selectively connect the mold space 33 to different pressure levels via the first group 35 of openings and the second group 37 of openings. The pressure regulation system 43 includes a vacuum source 45, which can be designed as a vacuum pump. In addition, the pressure regulating system 43 includes a first valve arrangement 49 and a second valve arrangement 51.

The first valve arrangement 49 has at least three functional states. In a first functional state of the first valve arrangement 49, the first group 35 of openings is via a lower pressure line 47 connected to the vacuum source 45. In a second functional state of the first valve arrangement 49, the first group 35 of openings is connected to an ambient pressure level 53. In a third functional state of the first valve arrangement 49, a connection of the mold space 33 is closed to the outside via the first group 35 of openings.

The second valve arrangement 51 also has at least three functional states. In a first functional state of the second valve arrangement 51, the second group 37 of openings is connected to the vacuum source 45 via the vacuum line 47. In a second functional state of the second valve arrangement 51, the second group 37 of openings is connected to the ambient pressure level 53. In a third functional state of the second valve arrangement 51, a connection of the mold space 33 is closed to the outside via the second group 37 of openings.

3A shows an initial state before the cover film 19 is sucked into the mold space 33. In the initial state, the first group 35 of openings is connected to the ambient pressure level 53 through the first valve arrangement 49 and the second group 37 of openings is connected to the ambient pressure level 53 through the second valve arrangement 51.

The graph 100 in 4 shows a time course of the pressure levels to which the mold space 33 is connected via the first group 35 of openings. The graph 200 in 4 shows a time course of the pressure levels to which the mold space 33 is connected via the second group 37 of openings. In graphs 100 and 200, the horizontal axis is a time axis and the vertical axis is a pressure axis.

The initial state in which the mold space 33 is connected to the ambient pressure level 53 via the first group 35 of openings and the second group 37 of openings is in 4 shown in time range 501.

3B shows the situation in a first time window 502 (see also 4 ). In the first time window 502, the mold space 33 continues to be connected to the ambient pressure level 53 via the second group 37 of openings. Via the first group 35 of openings, the mold space 33 is no longer connected to the ambient pressure level 53 in the first time window 502, but is connected to the vacuum source 45 via the vacuum line 47, so that a negative pressure 55 is created in the mold space 33 via the first group 35 of openings is created. As a result, the cover film 19 is sucked into the mold space 33. Since the second group 37 of openings provided in the lower region of the mold space 33 is still connected to the ambient pressure level 53, air flows into the mold space 33 through the second group 37 of openings. A pressure difference arises between a lower region of the mold space 33 and an upper region of the mold space 33 and an air flow 57 from the second group 37 of openings to the first group 35 of openings. The air flow 57 prevents the cover film 19 from coming into contact with the inner wall 31, at least in the area of the second group 37 of openings. Premature heating of the cover film 19 in a lower region of the side wall 31 and the associated weakening of the cover film 19 can thus be avoided or reduced .

The mold space 33 can be connected to the ambient pressure level 53 via the second group 37 of openings during the entire first time window 502. Alternatively, it would be possible, for example, that the second valve arrangement 51 during the second time window 502 between the second functional state of the second valve arrangement 51 (second group 37 of openings is connected to the ambient pressure level 53) and the third functional state of the second valve arrangement 51 (a connection of the mold space 33 via the second group 37 of openings is closed to the outside) switches back and forth or pulsates, in particular switches periodically. As a result, an air flow through the second group 37 of openings can be regulated, in particular set or regulated to a suitable value or in a suitable range.

3C shows a state in an optionally provided second time window 503 (see also 4 ). As in the first time window 502, the mold space 33 is connected to the vacuum source 45 via the first group 35 of openings. A connection of the mold space 33 to the outside via the second group 37 of openings is prevented by the second valve arrangement 51. This is in 4 represented by hatching. In the second time window 503, no more air can flow through the second group 37 of openings. The pressure in an area between the cover film 19 and the inner wall 31 is thus further reduced, so that the cover film 19 is pulled further into the mold space 33.

3D shows a state in a third time window 504 (see also 4 ). In the third time window 504, the mold space 33 continues to be connected to the vacuum source 45 via the first group 35 of openings. In the third time window 504, the mold space 33 is also connected to the vacuum source 45 via the second group 37 of openings. So it will be about both the first Group 35 of openings as well as the second group 37 of openings of the mold space 33 are subjected to a negative pressure 55. In this way it can be achieved that the cover film 19 is completely or at least essentially completely applied to the inner wall 31. In particular, in the third time window 504, the cover film 19 is sucked onto the inner wall 31 both in the area of the first group 35 of openings and in the area of the second group 37 of openings.

In the embodiment of 3A until 3D and 4 The first time window 502, the second time window 503 and the third time window 504 can follow one another directly or at a time interval.

5A shows a schematic sectional view through a molded body 29 of the closing station 3 according to the second embodiment. Openings are provided in the inner wall 31, which open into the mold space 33. The openings include a first group 35 of openings and a second group 37 of openings. The first group 35 of openings is provided in the lower region of the mold space 33, which is formed by a substantially vertical section of the inner wall 31 or a side wall section of the inner wall 31. The second group 37 of openings is provided in a ceiling area of the mold space 33, which is formed by a substantially horizontal section of the inner wall 31. The first group 35 of openings is connected to a first connecting channel 39. The second group 37 of openings is connected to a second connecting channel 41. A pressure regulating system 43 is provided, which can selectively connect the mold space 33 to different pressure levels via the first group 35 of openings and the second group 37 of openings. The pressure regulation system 43 includes a vacuum source 45, which can be designed as a vacuum pump. In addition, the pressure regulating system 43 includes a first valve arrangement 49 and a second valve arrangement 51.

The first valve arrangement 49 has at least three functional states. In a first functional state of the first valve arrangement 49, the first group 35 of openings is connected to the vacuum source 45 via a vacuum line 47. In a second functional state of the first valve arrangement 49, the first group 35 of openings is connected to an ambient pressure level 53. In a third functional state of the first valve arrangement 49, a connection of the mold space 33 is closed to the outside via the first group 35 of openings.

The second valve arrangement 51 also has at least three functional states. In a first functional state of the second valve arrangement 51, the second group 37 of openings is connected to the vacuum source 45 via the vacuum line 47. In a second functional state of the second valve arrangement 51, the second group 37 of openings is connected to the ambient pressure level 53. In a third functional state of the second valve arrangement 51, a connection of the mold space 33 is closed to the outside via the second group 37 of openings.

5A shows an initial state before the cover film 19 is sucked into the mold space 33. In the initial state, the first group 35 of openings is connected to the ambient pressure level 53 through the first valve arrangement 49 and the second group 37 of openings is connected to the ambient pressure level 53 through the second valve arrangement 51.

The Graph 300 in 6 shows a time course of the pressure levels to which the mold space 33 is connected via the second group 37 of openings. The Graph 400 in 6 shows a time course of the pressure levels to which the mold space 33 and the first group 35 of openings are connected. In graphs 300 and 400, the horizontal axis is a time axis and the vertical axis is a pressure axis.

The initial state in which the mold space 33 is connected to the ambient pressure level 53 via the first group 35 of openings and the second group 37 of openings is in 6 shown in time range 501.

In 5B is the operating situation in a first time window 502 (see also 6 ) shown. In the first time window 502, a connection of the mold space 33 is closed to the outside via the second group 37 of openings. This is in 6 shown hatched. In the first time window 502, the mold space 33 is connected to the negative pressure source 45 via the first group 35 of openings, so that the mold space 33 is subjected to a negative pressure 55 via the first group 35 of openings. The cover film 19 is thus sucked into the mold space 33. In the area of the first group 35 of openings, that is to say in a lower area of the mold space 33, the cover film 19 is sucked onto the inner wall 31. The cover film 19 lies against the inner wall 31 in the area of the first group 35 of openings and is held there. In particular, in the embodiment of 5A until 5C and 6 Place the cover film 19 on the inner wall 31 in the lower area of the mold space 33 before the cover film 19 is in place an upper region of the mold space 33 on the inner wall 31.

5C shows an operating situation during a third time window 504 (see also 6 ). In the third time window 504, the connection of the mold space 33 to the vacuum source 45 via the first group 35 of openings remains. In the third time window 504, the mold space 33 is also connected to the vacuum source 45 via the second group 37 of openings. The cover film 19 is thus sucked further upwards into the mold space 33. During the third time window 504, the cover film 19 also lies against the inner wall 31 of the mold space 33 in the upper region of the mold space 33. In particular, the cover film 19 can rest against the inner wall 31 essentially over the entire mold space 33 and be heated there essentially evenly.

In the embodiment of 5A until 5C and 6 The first time window 502 and the third time window 504 can follow one another directly or at a time interval.

QUOTES INCLUDED IN THE DESCRIPTION

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Cited patent literature

• DE 102018218382 A1 [0002]

Claims (15)

Method for packaging products, comprising: Positioning a lower packaging part (5) on a receptacle (27) of a closing tool lower part (15); Positioning a cover film (19) between the lower part of the closing tool (15) and an upper part of the closing tool (13) with a shaped body (29); and Suctioning the cover film (19) upwards into a mold space (33), which is defined by an inner wall (31) of the molded body (29), so that the cover film (19) rests against the inner wall (31); wherein openings are provided in the inner wall (31) which open into the mold space (33), the openings comprising a first group (35) of openings and a second group (37) of openings; wherein when the cover film (19) is sucked in, the molding space (33) is subjected to a negative pressure (55) via the first group (35) of openings, at least for the duration of a first time window (502); wherein at least for the duration of the first time window (502) the mold space (33) is not subjected to negative pressure via the second group (37) of openings; and wherein when the cover film (19) is sucked in, the molding space (33) is subjected to a negative pressure (55) via the first group (35) of openings and via the second group (37) of openings, at least for the duration of a third time window (504). . Procedure according to Claim 1 , wherein the mold space (33) is connected to an ambient pressure level (53) via the second group (37) of openings at least for the duration of the first time window (502). Procedure according to Claim 1 or 2 , wherein during the first time window (502) there is a gas flow through the second group (37) of openings into the mold space (33). Method according to one of the preceding claims, wherein the mold space (33) has a negative pressure over the first group (35) of openings at least for the duration of a second time window (503) lying between the first time window (502) and the third time window (504). (55) is acted upon, and wherein a connection of the mold space (33) via the second group (37) of openings to the outside is closed at least for the duration of the second time window (503). Method according to one of the preceding claims, wherein the first group (35) of openings is formed in an at least substantially horizontal region of the inner wall (31) and/or wherein the second group (37) of openings is formed in an at least substantially vertical region of the Inner wall (31) is formed. Procedure according to Claim 1 , wherein a connection of the mold space (33) via the second group (37) of openings to the outside is closed at least for the duration of the first time window (502). Procedure according to Claim 1 or 6 , wherein during the first time window (502) the cover film (19) is sucked onto the inner wall (31) in the area of the first group (35) of openings, but not in the area of the second group (37) of openings. Procedure according to one of the Claims 1 , 6 or 7 , wherein the first group (35) of openings is formed in an at least substantially vertical region of the inner wall (31) and / or wherein the second group (37) of openings is formed in an at least substantially horizontal region of the inner wall (31). . Closing station (3) for packaging, comprising a lower part of the closing tool (15), with a receptacle (27) for a lower part of the packaging (5); a closing tool upper part (17) with at least one molded body (29), the molded body (29) having an inner wall (31) which defines a downwardly open mold space (33); and a pressure regulation system (43) with at least one vacuum source (45), a first valve arrangement (49) and a second valve arrangement (51); wherein openings are provided in the inner wall (31) which open into the mold space (33), the openings comprising a first group (35) of openings and a second group (37) of openings; wherein the first valve assembly (49) is configured to connect the mold space (33) to the at least one vacuum source (45) via the first group (35) of openings, and is configured to connect the mold space (33) to the to prevent at least one source of negative pressure (45) via the first group (35) of openings; and wherein the second valve assembly (51) is configured to connect the mold space (33) to the at least one vacuum source (45) via the second group (37) of openings, and is configured to connect the mold space (33) to the to prevent at least one negative pressure source (45) via the second group (37) of openings. closing station Claim 9 , wherein the first group (35) of openings is provided in the upper 30 percent of a height of the mold space (33) and / or wherein the second group (37) of openings is provided in the lower 50 percent of a height of the mold space (33). closing station Claim 9 , wherein the first group (35) of openings is provided in the lower 50 percent of a height of the mold space (33) and / or wherein the second group (37) of openings is provided in the upper 30 percent of a height of the mold space (33). Closing station according to one of the Claims 9 until 11 , wherein the first valve arrangement (49) is configured to connect the mold space (33) to an ambient pressure level (53) via the first group (35) of openings and/or wherein the second valve arrangement (51) is configured to connect the mold space (33) to be connected to an ambient pressure level (53) via the second group (37) of openings. Closing station according to one of the Claims 9 until 12 , wherein the pressure regulation system (43) is configured to connect the mold space (33) to the at least one vacuum source (45) via the first group (35) of openings at least for the duration of a first time window (502) and to connect the mold space (33) with the at least one negative pressure source (45) via the second group (37) of openings at least for the duration of the first time window (502). closing station Claim 13 , wherein the pressure regulation system (43) is configured to connect the mold space (33) to an ambient pressure level (53) via the second group (37) of openings at least for the duration of the first time window (502). closing station Claim 13 , wherein the pressure regulation system (43) is configured to prevent a connection of the mold space (33) via the second group (37) of openings to the outside at least for the duration of the first time window (502).

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