The invention relates to the packaging sector and, in that sector, to a vertical tubular bag machine with a web of film unwound from a supply roll. A machine of this type has a shaping shoulder for shaping the web of film into a film tube and a vertically aligned filling pipe, which receives the film tube and through which it is possible to fill the film tube. A filling station, above the filling pipe, serves for this filling operation. Two film takeoffs, acting from opposite sides of the filling pipe against the film tube, and consequently against the filling pipe, are provided for further transportation of the web of film and the film tube. A longitudinal sealing device serves for welding the film tube by means of a longitudinal seam, aligned in the transporting direction, and a transverse sealing device with two welding jaws, which can be moved toward each other and weld the film tube transversely, serves for producing top seams and bottom seams of tubular bags. The completed tubular bags are severed from the film tube by means of a cutting device.
Vertical tubular bag machines of this type are sufficiently known. They generally serve for packing flowable or pourable products, such as granules for example. In principle, products in piece form can also be packed.
The known vertical tubular bag machines have the disadvantage that they are not very suitable for packing a series of groups of items in the form of a stack produced in tubular bags, since the groups turn during their free fall in the filling pipe, and consequently land in an uncontrollable manner in the welded end of the film tube. For reasons of simplification, a group of items is intended for the purposes of this application to mean either a single, horizontally aligned item, such as for example a coffee pod, or a group of two or more items arranged directly next to one another in a horizontal direction (such as coffee pods for example).
Because of this problem with falling, horizontal groups of items (single, double, triple group, . . . ) cannot be packed by means of vertical tubular bag machines. Instead, these groups are stacked into previously produced empty bags that are able to stand, which is comparatively laborious, and consequently expensive, since a vertical tubular bag machine has to be used in any case for producing the empty bags.
The invention is based on the object of designing a vertical tubular bag machine in such a way that it can be used for packing groups of items that are intended to form a stack in the tubular bag.
The object is achieved as specified in the defining part of claim 1. According to this, the filling station is intended for delivering in each case a horizontally aligned flat, preferably disk-shaped, group of items formed by one or more items, the filling pipe is adapted with respect to its cross section to the horizontal dimensions of the group of items in that the width and the depth of the filling pipe are made to match the width and the depth of a group of items and the group of items is placed above the filling pipe in such a way that there is a first equal spacing in the direction of the width and similarly there is a second equal spacing in the direction of the depth of the filling pipe on opposite sides of the group of items, in each case between the outer edge of the group of items and the inner surface of the filling pipe. These spacings do not all have the value zero. The filling pipe has a cross section that is symmetrical to two axes of symmetry of the group of items, and two pipe segments of the filling pipe that are opposite and parallel to each other, extend in the transporting direction and on which the film takeoffs act are provided.
The proposed vertical tubular bag machine is suitable for bringing groups of items directly into tubular bags approximately horizontally, so that a stack of groups of items is in this way produced in tubular bags. An exact horizontal alignment of the groups of items while they are being introduced is not necessary, since the groups of items align themselves horizontally during their stacking if they did not previously have an excessively great vertical aligning component. This component is minimized, since the filling pipe is adapted to the group of items. In this way there is initially an equal spacing between the group of items and the filling pipe on each opposite side (in a horizontal direction), which has the effect that no tilting moments act on a group of items at the beginning of the free fall.
Further, advantageous refinements of the proposed tubular bag machine are described in claims 2 to 4.
A favorable horizontal alignment of the groups of items is maintained during its free fall in the filling pipe if, by analogy with claim 2, the spacings have a value between 0 and 10 mm. Then the air respectively forced past the groups of items on opposite sides is present in equal amounts in a stabilizing way, or scarcely present in the same way. It also satisfies the homogeneity of the air flow in the filling pipe if, in the case of round items, in particular round coffee pods, according to claim 3, the walls of the filling pipe that lie opposite one another and are not intended for the film takeoffs to act on have an outwardly facing arc, an outwardly directed bend or at least two outwardly directed bends. In this case, the pipe segments may extend entirely over opposite walls (claim 4), in order to offer the film takeoffs a large area of engagement, which is of advantage for correct film running.
The invention is described in more detail below on the basis of figures representing exemplary embodiments, in which:
In the case of a vertical tubular bag machine 1 with a web of film 3 unwound from a supply roll 2, a shaping shoulder 4 serves for shaping the web of film 3 into a film tube 5 (
The outer edges 24 of the items 18, which are coffee pods with a disk-shaped bottom foil (
In the case of a second exemplary embodiment (FIGS. 3 to 6), the pipe segments 30, 31 extend entirely over opposite walls 36. The two other walls have either an outwardly facing arc 33 (FIGS. 3 to 5) or an outwardly directed bend 34, in order to achieve an identical air stream between the group of items 23, which comprises only one item 18, and the inner surface 25 of the filling pipe 6.
All the exemplary embodiments share the common feature that the edge 24 (
Number | Date | Country | Kind |
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102004016500.9 | Apr 2004 | DE | national |