OPENING DEVICE FOR OPENING A BAG SECTION OF A FILM WEB IN A BAG FILLING PLANT

Abstract

The invention relates to an opening device (10) for opening a bag section (210) of a film web (200) in a bag filling plant (100) for filling in bulk goods, comprising a suction device (20) for suctioning the two sides (212, 214) of the bag section (200) with an articulately supported first suction cup (22) on the first side (212) of the bag section (210) and an articulately supported second suction cup (24) on the second side (214) of the bag section (200), with at least one of the suction cups (22, 24) being arranged acute-angled in reference to the respective side (212, 214) of the bag sections (200).

Description

The present invention relates to an opening device for opening a bag section of a film web in a bag filling plant for filling with bulk goods.

In general it is known that bag filling plants are provided for filling bag sections of a film web with bulk goods. Here, the film web is embodied in several layers, so that two side layers are provided. In a filling station of a bag filling plant a bottom seam of the bag section is already provided, so that this bag section is only open towards the top. A funnel is inserted into this upper opening of the bag section in order to insert the bulk goods into the inside, thus the intermediate space between the two side layers, of the bag section.

In order to allow the secure insertion of the funnel and the bulk goods it is required to open the two sides and/or the two side layers of the bag section and this way provide an appropriate opening section. This is performed in bag filling plants of prior art by suction devices, which comprise at least two suction cups at the two sides of the bag section.

In bag filling plants of prior art and opening devices of prior art it is disadvantageous that the suction device is not operating in an ideal fashion under all operating conditions. For example, it may occur that the two suction cups contact the respective side of the bag section at both sides under a vacuum, however for the subsequent motion of the respective suction cup towards the outside the bag section fails to get entrained. This may be caused by different reasons. For example, by generating static charge between the two sides and/or side contacts of the bag section here increased adhesion may be given between these two sides of the bag section. It is also possible that other negative influences lead to an increased connection of the two sides to each other within the bag section. In such cases a subsequent attempt, thus a second trial, must occur for the suction device opening the bag section. This requires accordingly more time, extending the clock time of this station, and thus the processing speed of the entire bag filling plant.

The objective of the present invention is to at least partially correct the above-described disadvantages. In particular, the objective of the present invention is to improve the opening of the bag section in a cost-effective and simple fashion and particularly to shorten the clock time by reducing the occasions of faulty suction.

The above-stated objective is attained in an opening device with the features of claim 1. Additional features and details of the invention are discernible from the dependent claims, the description, and the drawings. Here, of course, the features and details described in the context with the opening device according to the invention also apply in the context to the dependent claims according to the invention and vice versa, so that with regards to the disclosure here alternating reference is made and/or can be made to the individual aspects of the invention.

An opening device according to the invention is embodied for opening a bag section of a film web in a bag filling plant to be filled with bulk goods. For this purpose, the opening device according to the invention comprises a suction device for suctioning the two sides of the bag section with an articulately supported first suction cup to the first side of the bag section and an articulately supported second suction cup to the second side of the bag section. The opening device according to the invention is characterized in that at least one of the suction cups is arranged at an acute angle in reference to the respective side of the bag section.

According to the invention the filling with bulk goods occurs in a filling station of the bag filling plant. The bag filling plant is here embodied e.g., according to the form, fill, and seal (FFS)-method. For this purpose, a film web is essentially continuously rolled off a supply roll. A conversion of the continuous advance of the film web into a cycled advance occurs via a buffer device, which may be embodied as a compensation device. Subsequently, a plurality of stations may be provided for processing the film web. For example, such stations may be a bottom sealing station with a cutting device, filling stations, a head sealing station, as well as a head seam-cooling station. The motion between the individual stations occurs via claw devices in a shuttle service.

A film web in the sense of the present invention is particularly embodied in two layers as a film tube. Accordingly, two side layers are embodied, which include an intermediate space between them. The bag section is cut to length, e.g., in a bottom sealing station, in which by a cutting device the individual bag sections are brought into their respective length. Simultaneously, a bottom seam is sealed in this bottom sealing station, in order to close the respective bag section at the bottom. An opening device according to the invention is preferably used in a filling station of the bag filling plant.

As already explained, the bag section is transported e.g., with the help of claw devices into the filling station of the bag filling plant. Here, the two sides and/or the two side layers of the bag section of the film web must be separated from each other in order to allow and/or enable inserting a funnel. This occurs with the help of the suction device. In an embodiment of prior art it comprises two suction cups, which are arranged at the two different sides of the bag section. Upon the arrival of the bag section in the filling station the two suction cups are made to approach the two sides of the bag section. Subsequently, a vacuum is applied via the suction cups, which particularly transfer a vacuum via the respective suction opening of the respective suction cup to the bag section and/or to its side. This way, a force towards the outside is applied upon the respective side of the bag section in order to separate these two sides and/or the two side layers of the bag section from each other. As soon as the two sides of the bag section have been suctioned by the respective suction cup, preferably a contrary motion of the respective suction cup occurs towards the outside such that the two sides are separated from each other and an opening develops between the two sides and/or the two side layers of the bag section. Now a funnel and/or directly the bulk goods can be inserted into this opening.

By the position of the suction device, particularly the two suction cups, an opening device is embodied for an explicit positioning of the bag section. Within the scope of the present invention the relative positioning is discussed between the respective suction cup and the respective side of the bag section. This relates here to the bag section and the side of the bag section as well as the position of the bag section and/or the position of the respective side of the bag section inside the opening device. In other words, by the opening device a respective correlation is defined to the position of the respective side of the bag section inserted into the opening device and positioned here accordingly. During the operation of the opening device accordingly the bag section with the respective sides is at this position such that the local correlation is given in the manner according to the invention.

Advantageously, now an explicit embodiment is given for at least one of the two suction cups. Namely, it is arranged at an acute angle in reference to the respective side of the bag section. When now a vacuum is applied via this suction cup, here no homogenous suctioning occurs of the respective side of the bag section. Rather, by the acute-angled arrangement one edge of the suction cup will be arranged closer to the side of the bag section than the opposite edge of the suction cup. The closer the suction cup is arranged to the side of the bag section the greater the effect of an appropriately applied vacuum. This leads to the fact that suctioning of the side occurs no longer homogenously over the entire suctioned area of the suction cup. Rather, the start of the suctioning process occurs no longer in a planar fashion but preferably in the area of a small section and/or directly at the edge of the respective suction cup, which is arranged closer to the side of the bag section. Subsequently, after the first opening motion in this suction area, the opening motion continues wavelike along the suction cup and/or along the suction area. This quasi leads to the side being peeled off the opposite side of the bag section.

By the embodiment according to the invention here the suction force is applied without any variation and/or enhancement upon a smaller suction area. This leads to the fact that the same suction force, due to the reduced area impinged, leads to an improved separating effect and/or an increased impact of force upon the respective side of the bag section. By the simple and primarily cost-effectively implemented geometric contacting at an acute angle of the respective suction cup, here using the same embodiment of the respective suction cups and the corresponding vacuum system and particularly also the same or essentially the same vacuum, an improved separating effect can be yielded by the described peeling function for both sides of the bag section.

Here, it is decisive that the acute-angled arrangement is particularly assumed in the position of the suction cups which are arranged particularly close to the side of the bag section. This particularly relates to the suction position as described in greater detail in the following.

By the targeted local reinforcement of the suction force, even in difficult separating conditions, thus particularly under increased situations of force between the two sides, which may be generated by static charge, here a secure peeling and/or opening of the bag section is possible. This way, the risk of any events of faulty suction can be reduced, so that respective delays in the cycle can also be reduced with regards to their probability of occurrence. The entire cycle time of this filling station and thus the entire operating velocity of the bag filling plant are considerably improved this way.

In general, according to the invention any arbitrary alignment of the acute angle is possible for the acute-angled arrangement. In particular, different angular directions may be combined with each other. This particularly relates to an angular arrangement in the top view and/or in the side view. Accordingly, particularly angular alignments may form as horizontal angles, thus as angles which extend in the horizontal level and/or as vertical angles and accordingly as angles in the vertical level. Here, a combination of horizontal angles and vertical angles in a dual-angular alignment is also possible in the present invention.

In the opening device according to the invention it may be advantageous for the suction cups to be supported in an articulate fashion between a suction position and an opening position. Here, the acute-angled arrangement of at least one suction cup is embodied for the suction position. As already mentioned, the suction cups are in an articulate bearing arrangement in the opening device. They may be shuttled between the opening position and the suction position. A minimum distance is given in the suction position between the respective suction cup and the side of the bag section. Here, suctioning occurs, as explained above, particularly by the peeling off-effect. When the suctioning has occurred successfully, the suction cups move into the opening position and here entrain the respective side of the bag section. The acute-angled arrangement is here of particular importance with regards to the functionality according to the invention, particularly in the suction position. Accordingly, it is decisive in general that at least in this suction position the respective suction cup assumes this acute-angled arrangement. This leads to the advantages according to the invention.

If with regards to greater freedom in design a different angular arrangement is advantageous or even a parallel embodiment of the respective suction cup in other positions, particularly in the opening position, this may be easily combined with an effect of the opening device according to the invention.

It may also be advantageous when in an opening device according to the invention the suction cups each show a suction area, which respectively defines a suction level. Here, the sectional line generated by the acute-angled arrangement extends between the respective suction level and the respective side of the bag section vertically or essentially vertically. A suction cup comprises preferably a suction opening and accordingly also a suction area, which by the suctioning effect may also come into contact with or into proximity of the side of the bag section. This suction area is preferably embodied in an essentially planar fashion and accordingly defines a suction level, which extends unlimited beyond the suction area. The bag section may also show an essentially planar and level extension so that particularly a straight line develops as the sectional line between the suction level and the respective side of the bag section. The vertical or essentially vertical arrangement of this sectional line means that the alignment in an acute-angled fashion occurs for the respective suction cup essentially exclusively with a horizontal angle. Here, the horizontal angle shall be understood as an angle which is exclusively measured in the horizontal level. This angular alignment is ideally discernible in the top view, which is therefore aligned directly to the horizontal level. Of course, a combination with a vertical angle may also be provided, as explained in greater detail in the following paragraph. By the vertical progression of the sectional line a lateral edge of the suction cup, also arranged essentially vertically, will show the shortest distance from the side of the bag section and thus from the start of the peeling off-process beginning at the respective side of the bag section. The vertical extension is here particularly an extension along or essentially along the lines of gravity. This shall be understood as the vertical extension of the sectional line as well as the perpendicular extension in reference to the base of the corresponding bag filling plant.

Another advantage is the fact that in an opening device according to the invention the suction cups show one suction area each, which respectively define a suction level. Here, the sectional line generated by the acute-angled arrangement between the respective suction level and the respective side of the bag section form an acute angle in reference to the vertical. Here, vertical is also understood as the alignment preferably along the line of gravity. Additionally, the vertical is also embodied particularly perpendicular in reference to the base of the bag filling plant. This embodiment is the dual-angular embodiment of the respective suction cup. Here, a combination between a horizontal angle and a vertical angle is provided such that the respective angular alignment is discernible both in the top view as well as in the side view of the respective opening device and thus the suction device. This dual-angular alignment particularly leads to the fact that the minimum distance between the suction cup and the adjacent side of the bag section can be reduced to an even smaller area. In particular, this section acts essentially punctually so that not only an edge of the suction cup but a corner of the suction cup shows the minimum distance. The trigger section, which shall be understood as the first impact area of the suction force, is here even further reduced so that accordingly the same force is applied upon a reduced area. This leads to a further amplification of the impact of force and accordingly to an even better separating behavior of the two sides of the bag section from each other.

Additionally, it is advantageous when in an opening device according to the invention both suction cups are arranged at an acute angle in reference to the respective side of the bag section, particularly in a manner symmetrical in reference to the bag section. Preferably, here the acute angularity and thus the corresponding advantages are provided for both suction cups. This way the peeling off-process is started at both sides. By the symmetric or also essentially symmetric embodiment with regards to the acute-angled arrangement of the two suction cups the start of the separation wave occurs, as already explained, for both sides of the bag section in the same or essentially the same fashion. This way, here too a simpler and/or more cost effective production of the suction device can be yielded.

Another advantage is given when in an opening device according to the invention the minimum distance between the respective suction cup and the side of the bag section is identical or essentially identical for both suction cups. The minimum distance has already been mentioned repeatedly and defines the shortest distance between a section of the suction cup and the side of the bag section. By the acute-angled alignment this minimum distance is the only angular alignment of the suction cup arranged over an edge of the suction cup and in a dual-angular alignment in a punctual area of the suction cup, thus a corner. When for both sides and thus for both suction cups this minimum distance is identical or essentially identical, here by identical selection of the vacuum for the two suction cups a similar or even identical situation of impacting force results for both sides of the bag section. Here, inequality of forces is avoided so that an even increased security can be provided for the opening process of the bag section. Of course, the same minimum distance may also be used at different angular arrangements of the suction cups in order to yield the same start of separation with different separating speeds.

Another advantage is achieved when in an opening device according to the invention the suction device comprises an adjustment device for adjusting the acute-angled alignment of at least one suction cup. Accordingly, a variation of the respective acute angle can be provided for the respective suction cup. This way, an adjustment is possible to different film materials. In particular, an adjustment to different thicknesses or different risk situations is possible with regards to static charge of the film web.

It is also advantageous when in an opening device according to the invention at least one of the suction cups shows at least one sealing lip embodied for sealing towards the side of the bag section. The sealing lip is embodied e.g., from a rubber material or another elastic material. It is geometrically correlated such that in the suction position of the suction cups sealing occurs by the sealing lip contacting the respective side of the bag section. This way, sealing is yielded towards any ventilation of secondary air. This sealing lip is at least provided at one side of the suction cup, preferably at two or three sides of the suction cup.

Preferably, at least one side edge of the suction cup is embodied free from the sealing lip, so that from here the vacuum can be generated for air to be resupplied. This further amplifies the suction effect by a defined air flow between the suction cups and the side of the bag section.

In one opening device according to the above-stated paragraph it may be further advantageous when the sealing lip compensates or essentially compensates the acute-angled arrangement of the respective suction cup to the side of the bag section. In other words, the sealing lip contacts or essentially contacts the side of the bag section in a parallel fashion. This way, sealing is yielded by the sealing lip preferably over the entire suction area of the suction cup. Lateral sealing lips may here be embodied with different depths, while a sealing lip mounted at the top shows a diagonal edge in order to allow compensation and thus parallel alignment to the respective side of the bag section.

It may also he advantageous when in an opening device according to the invention every suction cup is provided with a suction opening, which is embodied with a grid structure against suctioning in the bag section. Here, the suction opening shows a plurality of individual suction openings, which by the grid structure provide minimized individual suction areas. The suctioning in of the bag section is therefore prevented so that any jamming of the side of the bag section inside the suction opening can be avoided. This leads to a further improvement of the opening device and particularly also to an acceleration of the cycle time for this opening process.

Additional advantages, features, and details of the invention are discernible from the following description, in which the exemplary embodiments of the invention are described in detail with reference to the drawings. Here, the features mentioned in the claims and the description may be essential for the invention individually or in any arbitrary combination. It shows schematically:

FIG. 1 an exemplary embodiment of the bag filling plant,

FIG. 2a a bag section prior to the opening process,

FIG. 2b a bag section of FIG. 2a after the opening process,

FIG. 3 an exemplary embodiment of an opening device according to the invention,

FIG. 4a another embodiment of an opening device according to the invention,

FIG. 4b the embodiment of FIG. 4a in a top view,

FIG. 4c the embodiment of FIG. 4b in a side view, distorted,

FIG. 5a another embodiment of an opening device according to the invention, and

FIG. 5b another embodiment of an opening device according to the invention.

FIG. 1 shows an embodiment of a bag filling plant 100 according to the invention. In a supply roll, at the right, a film web 200 is wound off continuously. A conversion into a cycled advance of the film web 200 occurs via a buffer device in the form of a compensation device. In the following, individual stations 170 serve for processing the film web 200. Firstly, via a bottom sealing station and a cutting device the bottom seam is generated and the individual bag sections 210 are cut to length. The respective bag section 210 is transported via claw devices from the right towards the left to the further stations 170. A filling station 110 is provided as the next station. Subsequently, a head sealing station and a head seam-cooling station are provided as the station 170.

An opening device 10 according to the invention is particularly provided at a filling station 110. FIGS. 2a and 2b explain the opening process in greater detail. Here, the bag section 210 with its two sides 212 and 214 is shown schematically. It is also discernible that the two suction cups 22 and 24 of the suction device 20 engage the bag section 210 from two different sides 212 and 214.

The direction of motion after the suction process is shown by the two arrows. Thus, in the position according to FIG. 2a the two suction cups 22 and 24 are in the suction position S, as explained in the following in the context with FIG. 3. In FIG. 2b, after the suction process, an opening occurs of the two suction cups 22 and 24 by moving apart such that here the bag section 210 opens as well.

FIG. 3 shows in a top view, how an embodiment of an opening device 10 according to the invention may be embodied. For example, here the bag section 210 is discernible in a top view with its two sides 212 and 214. Two suction cups 22 and 24 of a suction device 20 are allocated to these two sides 212 and 214. The cups are capable to generate a vacuum via the suction area 26 and/or via a suction opening 21, not shown, and to ensure suction of the respective side 212 and 214 of the bag section 210.

It is also clearly discernible from FIG. 3 that the two suction cups 22 and 24, particularly their suction area 26, are arranged angular and particularly acute-angled in reference to the respective side 212 and 214 of the bag section 210. The acute-angled alignment occurs here via the horizontal angle γ, which in the top view coincides with the horizontal level and thus the level of the drawing. FIG. 3 also shows clearly the minimum distance A between the respective suction cups 22 and 24 and the respective side 212 and 214.

In FIG. 3 the suction device 20 is embodied with two symmetrically embodied suction cups 22 and 24, When the suction process occurs, suction of the respective side 212 and 214 of the bag section 210 occurs in the area of the minimum distance A. Subsequently, via a separating process, preferably in a wavy fashion, this separation process continues towards the bottom, as shown in FIG. 3, until a complete suction has occurred of the two sides 212 and 214 by the suction cups 22 and 24. Subsequently, the two suction cups 22 and 24 are moved out of their suction position S into the opening position O, also shown in FIG. 3, and here entrain the suctioned sides 212 and 214 of the bag section 210. This is equivalent to the opening of the bag section 210 as already explained with reference to FIGS. 2a and 2b.

FIGS. 4a through 4c show another embodiment of an opening device 10 according to the invention. Here, the suction device 20 is shown with regards to one of the two suction cups 22 and 24, namely with regards to the second suction cup 24. Of course, the opposite first suction cup 22 may be embodied in the same fashion. In this embodiment of the suction device 20 a sealing lip 50 is provided for sealing against the respective side 212 and 214 of the bag section 210. Here, too, it is clearly discernible in the schematic partial cross-section that the suction cup 24 comprises suction openings 21 and a grid structure 23 against suctioning in the bag section 210. FIG. 4a shows here the opening device 10 in a side view. FIG. 4b shows the top view with here again the horizontal angle γ being discernible for the acute-angled arrangement, Additionally, it is clearly discernible that this acute-angled arrangement with the horizontal angle γ is compensated by the sealing lip 50 such that, in spite of this acute-angled arrangement, the sealing lip 50 contacts the bag section 210 continuously and parallel at the side 214. FIG. 4c, which also shows a cross-section, here in a view from the bottom, shows circumferential sealing lips 50 at the top and left and right at the respective suction cup 24. Here too, again, the compensating effect for the horizontal angle γ by the sealing lip 50 is clearly discernible. However, in this illustration, an alternative embodiment of the suction cup 24 is discernible, because here the suction openings 21 vary with regards to their size by an altered grid structure 23. Here, it is also clearly discernible that a suction level 28 is defined by the suction area 26.

FIGS. 5a, and 5b show two other embodiments, particularly contacting options for the suction device 20. FIG. 5a shows the only contacting via a horizontal angle γ. This leads to the fact that an intersection forms 30 between the suction level 28 and the side 212 of the bag section 210, which extends vertically and/or horizontally. This sectional line 30 depends accordingly on the angular arrangement of the respective suction cup 22 and 24. FIG. 5b shows a dual-angular arrangement so that here not only a horizontal angle γ but also a vertical angle β provides an acute arrangement. Accordingly, the alignment of the suction level 28 also changes such that now the sectional line 30 extends at an acute angle α in reference to the vertical V. This therefore represents a dual-angular alignment and thus to another reduction of the impact of force upon a punctual area.

The above-stated explanation of the embodiments describes the present invention exclusively within the scope of examples. Of course, individual features of embodiments, to the extent technically beneficial, may be freely combined with each other without leaving the scope of the present invention.

LIST OF REFERENCE CHARACTERS

• 10 Opening device
• 20 Suction device
• 21 Suction opening
• 22 First suction cup
• 23 Grid structure
• 24 Second suction cup
• 26 Suction area
• 28 Suction level
• 30 Sectional line
• 50 Sealing lip
• 100 Bag filling plant
• 110 Filling station
• 170 Station
• 200 Film web
• 210 Bag sections
• 212 Side of the bag section
• 214 Side of the bag section
• A Minimum distance
• S Suction position
• O Opening position
• V Vertical
• α Angle in reference to the horizontal
• β Vertical angle
• γ Horizontal angle

Claims

1. An opening device (10) for opening a bag section (210) of a film web (200) in a bag filling plant (100) for filling in bulk goods, comprising a suction device (20) for suctioning the two sides (212, 214) of the bag section (200) with an articulately supported first suction cup (22) on the first side of the bag section (210) and an articulately supported second suction cup (24) on the second side (214) of the bag section (200), characterized in that at least one of the suction cups (22, 24) is arranged acute-angled in reference to the respective side (212, 214) of the bag section (200).

2. An opening device (10) according to claim 1, characterized in that the suction cups (22, 24) are supported articulately between a suction position (S) and an opening position (O), with the acute-angled arrangement of at least one suction cup (22, 24) being embedded at least in the suction position (S).

3. An opening device (10) according to claim 1, characterized in that the suction cups (22, 24) each show a suction area (26), respectively defining a suction level (28), with the sectional line (30) generated by the acute-angled arrangement extending vertically or essentially vertically between the respective suction level (28) and the respective side (212, 214) of the bag section (210).

4. An opening device (10) according to claim 1, characterized in that the suction cups (22, 24) each show a suction area (26), which respectively defines a suction level (28), with the sectional line (30) generated by the acute-angled arrangement comprising an acute angle (α) in reference to the vertical (V) between the respective suction level (28) and the respective side (212, 214) of the bag section (210).

5. An opening device (10) according to claim 1, characterized in that both suction cups (22, 24) are arranged acute-angled in reference to the respective side (212, 214) of the bag section (210), particularly in a manner symmetrical in reference to the be section (210).

6. An opening device (10) according to claim 1, characterized in that the minimum distance (A) between the respective suction cup (22, 24) and the side (212, 214) of the bag section (210) is identical or essentially identical for both suction cups (22, 24).

7. An opening device (10) according to claim 1, characterized in that the suction device (20) comprises an adjustment device for adjusting the acute-angled arrangement of at least one suction cup (22, 24).

8. An opening device (10) according to claim 1, characterized in that at least one of the suction cups (22, 24) comprises at least one sealing lip (50), which is embodied for sealing against the side (212, 214) of the bag sections (210).

9. An opening device (10) according to claim 8, characterized in that the sealing lip (50) compensates or essentially compensates the acute arrangement of the respective suction cup (22, 24) to the side (212, 214) of the bag section (210).

10. An opening device (10) according to claim 1, characterized in that each suction cup (22, 24) comprises a suction opening (21), which is embodied with a grid structure (23) against suctioning in the bag section (210).