METHOD AND DEVICE FOR FILLING BAGS

Abstract

A device and a method for filling bags with products, wherein the bags have an opening via which the bags are each filled with at least one product, wherein walls of the bag are spaced apart from one another in the region of the opening in order to introduce the at least one product into the bag via the opening, and wherein, after the walls are spaced apart and before the at least one product is supplied, holding elements are introduced into the bag through the opening in order to hold the open bag in the region of the opening. At least some holding elements have at least one shaping element against which a wall of the bag bears in each case such that the material of the wall is preferably plastically deformed in order to hold the wall on the respective holding element via the respective shaping element.

Claims

1. A method for filling bags (10) with products (11), wherein the bags (10) have an opening (28) via which the bags are each filled with at least one product (11), and wherein walls (20, 21) of the bag (10) are spaced apart from one another in the region of the opening (28) in order to introduce the at least one product (11) into the bag (10) via the opening (28), and wherein, after the walls (20, 21) are spaced apart and before the at least one product (11) is supplied, holding elements (24, 25) are introduced into the bag (10) through the opening (28) in order to hold the open bag (10) in the region of the opening (28), wherein at least some holding elements (24, 25) each have at least one shaping element (26) against which a wall (20) of the bag (10) bears in each case such that the material of the wall (20) is preferably plastically deformed in order to hold the wall (20) on the respective holding element (24, 25) via the respective shaping element (26).

2. The method as claimed in claim 1, wherein the material of the wall (20) is deformed in particular plastically such that the wall (20) is held on the respective shaping element (26) preferably exclusively by a form fit.

3. The method as claimed in claim 1, wherein the opening (28) of the bag (10) is enlarged by corresponding movement of at least one holding element, wherein a wall (20) of the bag (10) slides over the shaping elements (26) until the deformation (43) of the wall (20) is carried out by the shaping element(s) (27) while the bag (10) is correspondingly open.

4. The method as claimed in claim 3, wherein the shaping elements (26) bear against the wall (20) such that the deformation (43) takes place at a distance from an edge (44) of the wall (20) of the bag (10).

5. The method as claimed in claim 1, wherein the initial spacing of the walls (20, 21) of the bag (10) is carried out by means of at least one suction element, which acts on the outside of a wall (20) to be spaced and opens the bag (10), wherein it can preferably be provided for the wall (20) of the bag (10) not to be clamped between the suction element and the holding element.

6. The method as claimed in claim 5, wherein the at least one suction element is preferably deactivated and/or disengaged after the initial spacing of the walls (20, 21) of the bag (10), so that the bag (10) continues to be held in the open position only by the holding elements (24, 25).

7. A device for filling bags (10) with products (11), the device having holding elements (24, 25), wherein the bags (10) have an opening (28) via which the bags can each be filled with at least one product (11), and wherein walls (20, 21) of the bag (10) can be spaced apart from one another in the region of the opening (28) in order to introduce the at least one product (11) into the bag (10) via the opening (28), and wherein, after the walls (20, 21) are spaced apart and before the at least one product (11) is supplied, holding elements (24, 25) are introduced into the bag (10) through the opening (28) in order to hold the open bag (10) in the region of the opening (28), at least one of the holding elements (24, 25) has at least one shaping element (26) against which a wall (20) of the bag (10) bears in each case and is designed to deform the material of the wall (20) preferably plastically in order to hold the wall (20) on the respective holding element (24, 25) via the respective shaping element (26).

8. The device as claimed in claim 7, wherein the or each shaping element (26) has an in particular hemispherical or dome-shaped bulge (27), wherein it is preferably provided for the bulge (27) to have a radius of at least 1 mm.

9. The device as claimed in claim 7, wherein the or each shaping element (26) is designed to deform the material of the walls in particular plastically such that the wall (20) is held on the respective shaping element (26) by a form fit.

10. The device as claimed in claim 7, wherein the holding elements (24, 25) are designed as holding fingers (41), which can be positioned with a free end protruding into the opening (28) of the bag (10), wherein each of the holding fingers (41) has the shaping element (26), which is preferably arranged in the region of a free end of the respective one of the holding fingers (41).

11. The device as claimed in claim 10, wherein the device is designed to position the or each shaping element (26) at a distance from an edge of the opening (28) of the bag (10).

12. The device as claimed in claim 11, wherein the distance is such that the material of the wall (20) of the bag (10) between the bearing face of the shaping element and the edge (44) of the bag (10) is not under a tensile force directed in the transport direction (16) of the products into the bag (10).

13. The device as claimed in claim 7, wherein the transition from the respective shaping element (27) to the corresponding holding element (24, 25) is rounded.

14. The device as claimed in claim 7, wherein the at least one of the holding elements (24, 25) is at least partially rounded in cross section outside the shaping element.

15. The device as claimed in claim 7, wherein a region of the corresponding holding element (24, 25) that pivots into the bag (10) is trapezoidal in cross section.

16. The device as claimed in claim 7, wherein the at least one holding element (24, 25) has an L-shaped form, wherein the material strength in the corner region (45) of the L-shaped holding element (24, 25) is higher than at least one other region of the L-shaped holding element (24, 25).

17. The device as claimed in claim 7, wherein the at least one holding element (24, 25) is mounted pivotably so that the holding finger(s) (41) with the shaping element (26) can be pivoted into the bag (10).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] A preferred exemplary embodiment of the invention is explained below using the drawings. In the figures:

[0034] FIG. 1 shows a device for filling bags in a schematic, three-dimensional diagram,

[0035] FIG. 2 shows a vertical section through the device along section line II-II in FIG. 1,

[0036] FIGS. 3 and 4 show a detail of the device on an enlarged scale in region III in FIG. 2 in successive movement phases,

[0037] FIG. 5 shows a detail of the device on an enlarged scale in region VI in FIG. 4,

[0038] FIG. 6 shows a horizontal section through the device along section line VI-VI in FIG. 5,

[0039] FIG. 7 shows a diagram corresponding to FIG. 2 on an enlarged scale, and

[0040] FIG. 8 shows a vertical section through the device along section line VIII-VIII in FIG. 1 in successive movement phases.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0041] The invention is described below with reference to a device for packaging groups of diapers into bags 10. Since other articles are, however, also possible as package contents, the general term product 11 is used below. The product 11 to be packaged also does not have to be a group of products; one or more individual products or multiple groups of products are also possible. In this respect, the terms are used synonymously below.

[0042] The products 11 are supplied as a group to a compressing station 12. Here, the group of products 11 is then compressed and subsequently pushed into a shuttle 14 by means of a pushing means 13. The compressing station 12 can be considered useful for the present groups of diapers but can of course be omitted for other products.

[0043] The shuttle 14 can be, as shown, an elongate guide that can be moved back and forth in the transport direction 16 and holds the group of products 11 together laterally and in a compressed state. Other guides known from the prior art are also conceivable here.

[0044] The method consists substantially of the following steps:

[0045] The pushing means 13 and the shuttle 14 are conveyed together with the group of products 11 in the transport direction 16 to a bag-opening station 15. In the bag-opening station 15, bags 10, folded flat, are kept ready one above the other in stacks in a bag magazine 17. The respective bag stacks are conveyed toward the bag-opening station 15 and positioned correspondingly under same (see FIG. 1). The bag stacks are lifted by means of a lifting station 18, received by two movable fork holders 19, and brought to the height level of the shuttle 14 (see FIG. 2).

[0046] It is self-evident that the bags 10 can of course also be processed individually, and therefore the bag magazine 17 shown here can be omitted, at least at this point or overall.

[0047] Suction elements in the form of a pair of suction grippers 22 are lowered onto the top wall 20 of the top bag 10 and suck up and hold the upper wall 20. When the suction elements are subsequently lifted, the upper wall 20 is carried along and the bag 10 is opened slightly. As a counterpart to the lifting, a lower wall 21 of the bag 10 is held by a bottom plate 23 that protrudes into the bag 10. In this way, the bottom plate 23 acts as a holding element for the bag 10.

[0048] When the bag 10 is slightly opened in this way (by lifting with the suction elements), two further holding elements 24, 25 pivot into it. The suction elements and the pivoted-in holding elements 24, 25 move further upward and carry the wall 20 with them.

[0049] The holding elements 24, 25 are shaped such that they each have a shaping element 26 on their free end or in the vicinity thereof. In the present case, the shaping elements 26 are each designed as bulges 27.

[0050] During the upward movement of the suction elements and the holding elements 24, 25, the bag material is not clamped fixedly between them, but rather the upper wall 20 of the bag 10 is tensioned over the holding elements 24, 25 and the respective shaping elements 26 thereof so that a rectangular (bag) opening 28 is formed (see FIG. 9).

[0051] The contour of the bulge 27 causes the bag material to be deformed (overstretched) plastically over same at the end of the unfolding process but without tearing. The form-fitting connection thus produced between the bag material and the shaping element 26 means that the tensile force 29 that arises during the insertion of the shuttle 14 into the bag 19 and is directed in the transport direction 16 (see FIG. 5 and FIG. 6) is absorbed via the bag material. Via the resistance thus introduced, the bag 10 is held securely during the entire insertion process, and uncontrolled sliding of the bag 10 off the holding elements 24, 25 is prevented.

[0052] Since fixed clamping of the bag material is not used in this method, a further advantage results: Throughout the opening of the bag 10, the material of the upper wall 20 can slide unhindered into the unfolding side walls. As a result of the tensile forces 30 that arise during unfolding and are directed transversely to the transport direction 16, the upper wall 20 is tensioned, and therefore the wall 20 is prevented from sagging in the unfolded state of the bag 10. Both the product 11 and the shuttle 14 can be inserted unhindered into the open bag 10.

[0053] The suction elements can either remain activated during unfolding of the bag 10 or be switched off after the bag 10 is opened. As shown in FIG. 9, the wall 20 is pulled or peeled off the suction elements during unfolding of the bag 10, and therefore the suction elements are then no longer needed in any case and can be deactivated if desired.

[0054] When the shuttle 14 and the pushing means 13 move into the open bag 10, the group of products 11 is conveyed to just before the bottom 31 of the bag 10. The shuttle 14 is then moved back toward the starting position, while the pushing means 13 pushes the products 11 out of the shuttle 14 as far as the bottom 31 of the bag 10.

[0055] The pushing means 13 then pushes the products 11 further toward a sealing/cutting station 32, and the bag 10 is pulled off the holding elements 24, 25 in the process.

[0056] Overlapping with the movement of the shuttle 14 toward the starting position, the suction elements and the holding elements 24, 25 are already lowered again to pick up the next bag 10 (see FIG. 7). This movement overlap is possible because both the suction elements and the holding elements 24, 25 are structurally located outside of the working region of the shuttle 14 (see FIG. 8 and FIG. 9).

[0057] Finally, the filled bag 10 is supplied to a sealing/cutting station 32 in which the bag 10 is closed in a known manner (see right-hand region of FIG. 7). This means that an end-face bag seam is fused by means of sealing jaws 33, 34 moved toward one another, and the excess material is cut off before it is removed from the machine via a suction duct (see right-hand region of FIG. 2). With the material thus cut off, the plastic deformations in the bag material, caused by the overstretching on the bulge 27, are also removed from the finished bag 10.

[0058] In the case of large bags 10 (e.g., for multi-row diaper formats), the region in which the bag 10 is unfolded can also be critical just because of the holding elements 24, 25 with the bulge 27. The weight of the bag 10 and the overhang thereof in the bag supply can mean that the bag 10 is pulled off the bulges 27 of the holding elements 24, 25 while it is being pulled open (range between initial opening by suction element and complete unfolding by and via the holding elements 24, 25).

[0059] In order to ensure reliable opening of large bags 10, the opening process can be designed as follows:

[0060] First, the suction elements lowered onto the bag magazine 17 (as described above) grip the upper wall 20 and create a first opening gap. The holding elements 24, 25 with bulges 27 pivot into this gap until they come to a stop against a fixed counterpart (e.g., the suction elements). In the process, the bag material is correspondingly clamped fixedly between the holding elements 24, 25 and the counterpart. The bag 10 thus remains in position while being pulled open and cannot be pulled off the holding elements 24, 25.

[0061] Shortly before the suction elements and the pivoted-in holding elements 24, 25 reach their upper end position, the holding elements 24, 25 are pivoted away (slightly) from their counterpart, the fixed clamping of the bag material is opened, and the unfolding of the bag 10 continues only via the holding elements 24, 25. Here too, the material is then correspondingly overstretched over the bulges 27 on the holding elements 24, 25 and held as already described above until the bag 10 with the products 11 is finally pulled off by means of the pushing means 13.

[0062] The device also has the following characteristics:

[0063] The bag stacks are supplied to the bag magazine 17 along a track plate 35. Transport takes place by means of a toothed belt 36 that has pins 37 that engage (from below) into corresponding holes in the bags 10. When the bag stack is lifted, the bags are pulled off the pins 37, and pins 38 on the bottom plate 23 engage (from above) into the holes (FIGS. 2 and 3).

[0064] The holding elements 24, 25 are in the form of holding fingers. The holding elements 24, 25 are arranged pivotably on a holder 39, on which a suction element is also mounted. In this way, a holding element 24, 25 can be moved together with a suction element (in the vertical direction).

[0065] The holding elements 24, 25 preferably have the bulge 27 at a free end. In each case, a portion with a flat top is arranged in front of the bulge 27. This so-called straight region 40 ensures that the plastic deformation only takes place in the region of the bulge 27 that is set back relative to the bulge 27 and not in the straight region 40.

[0066] The holding elements 24, 25 are L-shaped in cross section, with two arms that meet in a corner region 45. The arm protruding into the bag 10 has the bulge 27 and the straight region 40 and acts as a holding finger 41. The other arm 42 is used for pivotable mounting on the holder 39.

[0067] FIG. 6 shows the region in which the preferably plastic deformation 43 is arranged, specifically at a distance from the bag edge 44.

[0068] It is also provided for the transition from the respective shaping element to the corresponding holding element 24, 25 to be rounded. In this way, sharp edges can be avoided in this region in order to assist better sliding of the bag material when the bag 10 is pulled off.

[0069] Furthermore, it is provided for the holding elements 24, 25 to be at least partially rounded in cross section outside the shaping element in order to make it easier for the bag material to slide over the holding elements 24, 25.

[0070] It is also provided for a region of the holding elements 24, 25 that pivots into the bag, specifically the holding fingers 41, to be trapezoidal in cross section. An advantage of this solution can consist in being able to absorb, as well as possible, the load occurring in this region and resulting from the bag material being tensioned thereover.

[0071] It is also provided for the material strength in the corner region 45 of the holding elements 24, 25 to be higher than other regions, in particular in order to protect the holding elements 24, 25 from bending open and any occurring transverse bending as a result of the unfolding of the walls of the bag 10.

[0072] A pivoting-in mechanism for the holding element(s) 24, 25 can be operated, for example, pneumatically, electrically, magnetically or mechanically.

[0073] It is self-evident that the bags 10 can of course also be handled in another orientation and do not have to lie flat. Accordingly, the bag 10 is then aligned in an appropriate direction. In this respect, the invention is not limited to the horizontal/vertical orientation shown but can in principle also be implemented in other orientations.

LIST OF REFERENCE SIGNS

[0074] 10 Bag [0075] 11 Product [0076] 12 Compressing station [0077] 13 Pushing means [0078] 14 Shuttle [0079] 15 Bag-opening station [0080] 16 Transport direction [0081] 17 Bag magazine [0082] 18 Lifting station [0083] 19 Fork holder [0084] 20 Wall (upper) [0085] 21 Wall (lower) [0086] 22 Suction gripper [0087] 23 Bottom plate [0088] 24 Holding element [0089] 25 Holding element [0090] 26 Shaping element [0091] 27 Bulge [0092] 28 Opening (bag) [0093] 29 Tensile force (longitudinal) [0094] 30 Tensile force (transverse) [0095] 31 Bottom (bag) [0096] 32 Sealing/cutting station [0097] 33 Sealing jaw [0098] 34 Sealing jaw [0099] 35 Track plate [0100] 36 Toothed belt [0101] 37 Pin (toothed belt) [0102] 38 Pin (bottom plate) [0103] 39 Holder [0104] 40 Region [0105] 41 Holding finger [0106] 42 Arm [0107] 43 Deformation [0108] 44 Bag edge [0109] 45 Corner region