EP0293615B1 - Device for filling and closing paper bags with gussets folds - Google Patents

Description

The invention relates to a device for filling and closing sacks or bags according to the preamble of claim 1.

In known devices of this type (DE-C-483 688) it is disadvantageous that numerous operations have to be carried out in a single station, for example opening, filling and closing. Filling stations of this type therefore have the disadvantage that their working speed is comparatively low.

It is also known in so-called Roto-Packers to divide the different operations over several processing stations, with the result that a higher performance of such machines can be achieved.

A disadvantage of the Roto packers mentioned is, above all, the fact that a format change on such machines is very time-consuming and complex.

Based on this prior art, the invention has for its object to design a device of the type presumed to be known in such a way that its filling capacity increases, the changeover from one sack format to another should also be possible at short notice on a small scale.

This object is achieved with the features of the labeling part of claim 1.

The provision of external grippers, which grip the sack in its side folds, allows the opened and filled or partially filled sack to be transported to the next processing station without the sack having to be closed beforehand. In this way, for example, the filling process can also be divided up in such a way that the main quantity of the dosing material is filled in and possibly pre-compressed in a first filling station, while the remaining quantity can be precisely metered in in a second filling station. The provision of external grippers, which are moved in the invention with a cyclically reciprocating carriage, thus allows the operations otherwise occurring at a processing station to be distributed over a plurality of individual stations arranged one behind the other.

Compared to the known transport systems, for example transport belts attacking in the vicinity of the opening, the external grippers according to the invention, which grip the outer folds of the sack, have the advantage that they enable a substantially better utilization of the filling volume of the sack. In addition, such external grippers allow a secure fixation and a safe transport in the defined position desired in each case. This also applies if four external grippers are provided in the three successive processing stations, that is to say in the pre-opening station, in the filling station and in the closing station, which take over the sack one after the other. Various suction elements or suction strips are provided in the construction according to the invention. Such suction elements or suction strips are used in the pre-opening station to pre-open the sack and ensure that the outer folds of the pre-opened sack can be gripped by external grippers. In the other stations, suction strips may be used to support the holding effect.

The drive members for moving the outer grippers and / or the suction strips apart or preferably are preferably arranged at an acute angle that deviates from the horizontal, which is usually 45 °. This acute-angled arrangement allows the system to be adapted very quickly to different sack formats. The external grippers and / or suction strips are not only moved further towards the center due to the inclined arrangement of the drive when the bag format is reduced, but at the same time further downwards, as is necessary when the format is changed.

This makes it possible to change the bag formats solely by providing different adjustment paths for the drive elements. For this purpose, for example, different mechanical stops corresponding to the different bag formats can be provided or the adjustment paths can be set with special drives. It would also be possible to move any mechanical stops provided with servo motors to the desired position as required. This would allow the bag formats to be changed automatically.

In a preferred embodiment of the invention, the stops sit on a disc which can be pivoted about an axis. Such an arrangement proves to be particularly robust and reliable. If the stops are formed, for example, by adjustable screws, a fine adjustment can be made to the stops if necessary.

According to a further feature, in the closing station, in which the side folds are folded in and the longitudinal walls are moved together, the drive of the fixed four external grippers is coupled to the drive for the folding members inserting the side folds. Such a coupling by means of a coupling linkage ensures that the adjustment path of the folding members is also automatically adjusted when the format is changed.

Furthermore, it proves to be expedient for a sealing station to be followed by a sealing station in which the plastic layer is welded in the region of the fold line if a plastic layer of the paper sack is provided.

It is particularly advantageous that welding jaws are provided at the welding station for welding the sack in the upper lateral corner areas. The welding of the welding jaws in the upper corner area is completely free of prototypes. As a result, a side gusset bag closed in this way assumes a shape which is very close to the ideal shape of the cuboid after the final closing.

It is also proposed according to the invention that a first folding station, in which a first folding takes place, is followed by a second folding station for a second folding.

Further features of the invention result from the further subclaims and from the following description in conjunction with the drawing.

Figur 1 -

eine schematische Draufsicht auf die Vorrichtung mit verschiedenen hintereinander angeordneten Bearbeitungsstationen,

Figur 2 -

eine schematische Seitenansicht der Voröffnungsstation bei geschlossenem zugeführten Sack,

Figur 3 -

eine Draufsicht auf die Voröffnungsstation gemäß Figur 2,

Figur 4 -

eine Seitenansicht analog Figur 2 in vorgeöffneter Position des Sacks,

Figur 5 -

eine Draufsicht auf die Voröffnungsstation gemäß Figur 4,

Figur 6 -

eine schematische Seitenansicht der Füllstation in einem Teilbereich,

Figur 7 -

eine Draufsicht auf die Füllstation bei entferntem Fülltrichter,

Figur 8 -

eine Seitenansicht der Verschließstation in Längsrichtung der Maschine gesehen,

Figur 9 -

eine Draufsicht auf die Verschließstation,

Figur 10 -

eine Seitenansicht auf die Seitenfaltorgane in der Verschließstation, quer zur Längsrichtung der Maschine gesehen,

Figur 11 -

eine Draufsicht auf zwei Außengreifer der Verschließstation,

Figur 12 -

eine Seitenansicht der Verschließstation in einer teilweise zusammengeschobenen Position,

Figur 13 -

eine Draufsicht analog Figur 9 in teilweise zusammengefalteter Position des Seitenfaltensacks,

Figur 14 -

die Anordnung gemäß Figur 10 mit eingefahrenen Seitenfaltorganen,

Figur 15 -

eine Darstellung gemäß Figur 11 mit eingefalteten Seitenfaltorgan,

Figur 16 -

eine perspektivische Darstellung eines Seitenfaltensacks mit abgeschweißten Eckbereichen,

Figur 17 -

eine perspektivische Darstellung des gefüllten und verschlossenen Sacks,

Figur 18 -

eine Doppelfalzeinrichtung in einer ersten Position in einer ersten Seitenansicht,

Figur 19 -

die Doppelfalzstation gemäß Figur 18 in einer zur ersten Ansicht senkrechten Seitenansicht,

Figur 20 -

die Doppelfalzeinrichtung in einer weiteren Arbeitsphase,

Figur 21 -

die Doppelfalzeinrichtung in der letzten Arbeitssphase.

A preferred exemplary embodiment of the invention is explained in detail below with reference to the drawing. Show it:

Figure 1 -

2 shows a schematic top view of the device with different processing stations arranged one behind the other,

Figure 2 -

FIG. 2 shows a schematic side view of the pre-opening station with the supplied bag closed, FIG.

Figure 3 -

2 shows a plan view of the pre-opening station according to FIG. 2,

Figure 4 -

2 shows a side view analogous to FIG. 2 in the pre-opened position of the sack,

Figure 5 -

3 shows a plan view of the pre-opening station according to FIG. 4,

Figure 6 -

a schematic side view of the filling station in a partial area,

Figure 7 -

a plan view of the filling station with the filling funnel removed,

Figure 8 -

a side view of the closing station seen in the longitudinal direction of the machine,

Figure 9 -

a plan view of the sealing station,

Figure 10 -

a side view of the side folding organs in the closing station, seen transversely to the longitudinal direction of the machine,

Figure 11 -

a plan view of two external grippers of the closing station,

Figure 12 -

a side view of the closing station in a partially pushed position,

Figure 13 -

9 shows a top view analogous to FIG. 9 in the partially folded position of the gusseted bag,

Figure 14 -

10 the arrangement according to FIG. 10 with the side folding elements retracted,

Figure 15 -

11 shows a representation according to FIG. 11 with the side folding member folded in,

Figure 16 -

1 shows a perspective illustration of a gusseted bag with welded corner areas,

Figure 17 -

a perspective view of the filled and closed sack,

Figure 18 -

a double folding device in a first position in a first side view,

Figure 19 -

18 the double folding station according to FIG. 18 in a side view perpendicular to the first view,

Figure 20 -

the double folding device in a further work phase,

Figure 21 -

the double folding device in the last working phase.

A machine frame 35 carries a plurality of guide tubes 36 arranged on both sides and distributed over its length, on which the guides of a slide, which is designated by 1, are mounted in a longitudinally displaceable manner. The device shown in FIG. 1 has various stations, namely a pre-opening station 6, the subsequent filling station and then the closing station 7, which can also be designed as a refilling station and closing station. This is followed by a welding station 8, a first folding station 9, a reserve station 11, which is provided for inserting handles, and finally a second folding station 10.

The structure of these different stations can be seen better from the individual illustrations:
In the pre-opening station, the individual bags arriving in a package are removed from the package by suction devices and moved between suction strips 15. The suction strips 15 are moved apart via the drive cylinders 18 and 19, namely until they abut one of the stops 24 and 25 arranged several times on the two cylindrical disks. These stops 24 and 25 are designed as screws and can because of their Screw character can be finely adjusted by screwing in or out. The desired stop 24 or 25 is brought into position in accordance with the desired sack format.

With the help of the suction strips 13 and 15, the sack 3 is partially opened, to the extent that the outer grippers 13 can press the outer folds against corresponding counterholders. The external grippers are designed as pivotable grippers that work with a corresponding drive, which is not shown in detail.

The pre-opened sack 3 is moved by means of the slide 1 into the filling station 4 under the stationary filling funnel 37. The pre-opened sack is then gripped by the stationary, also swiveling grippers 2 connected to the two suction beams, which can be moved against and apart from one another. During the filling process, the carriage 1 can move back to pick up a new sack in the pre-opening station. When moving back, the grippers 12 attached to the carriage 1 move out of the closing station and into the takeover position shown in FIGS. 6 and 7, in which they grip the filled sack 3 in a clamped manner. The stationary grippers 2 are released and, with the next working stroke, the carriage uses the grippers 12 to convey the filled sack 3 from the filling station to the closing station 7.

In the closing station, both externally arranged grippers 14 are provided as well as stationary folding members or folding members 26 and 27.

When the drive cylinders 20 and 21 are moved, the folding members 26 and 27 are carried along by means of a coupling linkage 38. When moving together to close the sack (see FIGS. 12-15), the folding members 26 and 27 insert the gussets. As soon as the fold-in position shown in FIGS. 12 to 15 has been reached by means of the outer grippers 14 and the fold-in members 26 and 27, two clamping strips 39 and 40 clamp the almost completely folded bag. The clamping strips 39 and 40 are fastened to the slide 1 and transport the clamped sack further into the welding station with the next stroke. In the welding station, in the first folding station and in the second folding station, as well as in the reserve station, terminal strips, the drive of which is not shown in more detail, are provided for the further transport of the processed sack.

In the welding station 8, the bag is welded along an upper fold line. It is possible that the corner regions 29 and 30 are also welded by appropriate design of the welding jaws.

The first folding takes place in the subsequent folding station, which is done in the usual way and cannot be described in detail. Double folding is carried out in the second folding station.

Double folding is carried out in the second folding station. This is done with the aid of a folding knife 31 which is movable transversely to the longitudinal movement of the sack and which moves the sack above the clamping strips between the folding jaws 32 and 33 of a folding pliers designated by 34.

The sack area gripped in this way is then pressed onto the sack area below by pivoting the entire folding tongs (cf. FIG. 34) by means of the pressure piece 40 shown in FIGS. 21 and 22, which sits on the folding jaw 32. Due to the adhesive previously applied to the corresponding points, the double-folded sack 3 is firmly bonded in the position shown in FIG.

In the above description, the term "stationary" has been used in the sense that it means that the parts designated in this way do not move with the carriage 1. However, the parts labeled "stationary" are not stationary, but can be moved.

Claims (15)

1. Device for filling and closing side folded sacks (3) with a filling station in which a weighed amount of filling material is filled from a supply container into the sack (3) which is held in the opened position by locally fixed clamping members (12), furthermore with a slide carriage (1) which is movable over a straight stroke corresponding to the spacing of the processing stations,
   characterised in that on the slide carriage (1) there are outside grippers (12) for gripping the sack (3) in the outer side folds wherein these grippers clampingly grip the filled or partially filled sack (39) in the filling station (4) and transport same by means of the slide carriage (1) into the following processing station (7).
2. Device according to claim 1
   characterised in that four outside grippers (12;13;14) are each mounted at least double on the slide carriage 1 spaced out according to the successive processing stations.
3. Device according to claim 1 or 2
   characterised in that suction elements for initially opening the at first closed sack (3) are provided in a first station (6) to which the empty sacks (3) are supplied.
4. Device according to claim 3
   characterised in that the suction devices are suction strips (15) mounted parallel to the transport direction.
5. Device according to one or more of claims 1 to 3
   characterised in that the locally fixed clamping members provided in the filling station (4) are four outside grippers (2).
6. Device according to one or more of claims 1 to 5
   characterised in that in addition to the four outside grippers (12;13;14) suction devices (15;16) are provided on the slide carriage (1) spaced out according to the following processing stations.
7. Device according to one or more of claims 1 to 6
   characterised in that the drive members (18;19;20;21;22;23) for spreading apart and bringing together the outside grippers (12;13;14) and/or the suction strips (15;16;17) are mounted at an acute angle deviating from the horizontal.
8. Device according to one or more of claims 1 to 7
   characterised in that to adjust the processing stations (6;4;7) to different sack formats, stops (24;25) are provided corresponding to the different sack formats to restrict the displacement paths of the drive members (18;19;20;21;22;23)
9. Device according to claim 8
   characterised in that the stops (24;25) are seated on a disc (26) which can swivel about an axis.
10. Device according to one or more of claims 1 to 9
    characterised in that in the closing station (7) in which the side folds are turned in and the longitudinal walls are brought together, the drive of the locally fixed four outside grippers (14) is coupled to the drive for the folding-in members (26;27) which turn in the side folds.
11. Device according to claim 10
    characterised in that the folding-in members (26;27) are connected by a coupling rod to the drive for the clamping members so that any corresponding adjustment of the displacement path of the folding-in members (26;27) is linked simultaneously to a format adjustment at the drive members.
12. Device according to one or more of claims 1 to 11
    characterised in that a closing station is followed by a welding station (8) in which where the paper sack is provided with a weldable plastics layer, the plastics layer is welded in the area of the fold line.
13. Device according to claim 12
    characterised in that welding jaws for welding the sack (3) in the side upper corner areas (29;30) are provided at the welding station (8).
14. Device according to one or more of claims 1 to 13
    characterised in that a first folding station (9) where a first folding-over is carried out is followed by a second folding station (10) for a second folding-over.
15. Device according to claim 14
    characterised in that the second folding station (10) has a folding blade (31) movable across the sack and designed for sliding the pre-folded sack between the mutually swivelling folding jaws (32;33) of a pincer (34) wherein the entire pincer (34) is designed to swivel to press the seized sack area onto the adjoining sack area underneath.

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