WO2000066433A1 - Packaging machine and method for producing, filling and sealing narrow tubular bags - Google Patents

Abstract

The invention relates to a method and a packaging machine for producing, filling and closing notably narrow tubular bags. According to said method a bag is produced from a strip of packaging material such that it is still open on one side, filled and then closed. According to the invention the packaging material is a film which is characterized by sufficient stiffness during sliding and from which a longitudinally sealed tube is formed in a continuous, cyclic manner. When a length of tube equivalent to a bag is advanced the lower, open end of this tube is positioned on a mandrel having an adapted cross-section and said length of tube is cold separated. Thereafter the upper end of the bag of packaging material is closed at a point corresponding to at least one cycle distance, the resulting piece of tube is turned inside out, withdrawn from the mandrel and after at least one filling closed by transverse sealing at a point corresponding to a suitable cycle distance.

Description

 PACKING MACHINE AND METHOD FOR PRODUCING, FILLING AND SEALING NARROW TUBE BAGS

BACKGROUND OF THE INVENTION

1 . Field of the invention

The invention relates to a packaging machine and a method for producing, filling and closing, in particular, narrow or slim tubular bags.

2. Description of the prior art

Such a method with an associated machine is known for example from German patent application DE 44 29 148 AI. This involves the manufacture, filling and sealing of packaging in the form of tubes, although it is not assumed that the tube bodies are prefabricated, but that they are formed in a known manner from a correspondingly wide packaging material web on a shaped tube, the bottom first being formed by a Cross seal seam produced, the separated piece of tubing filled and finally the tube head is inserted and sealed.

The disadvantage here is that a packaging length is cut off directly under the still hot cross seal or bottom seam, which can lead to sticking in the cutting area and thus to difficulties in the subsequent filling and insertion of the tube head or the tube shoulder. The endless conveyor arranged under the shaped tube for the removal and further transport of the separated hose pieces must also be equipped with relatively complex gripper mechanisms in order to be able to grasp the bottom sealed seams of the hose pieces. The application of the bottom sealed seam as the first step after the tube shaping also affects the shape of the tube upward continuing piece of tubing, that is, its open top end has a tendency to orientate in the direction of extension of the bottom seam, which makes it difficult to insert the filling nozzle of the packaging machine and also the tube head piece.

OBJECTS AND SUMMARY OF THE INVENTION

The invention has for its object to provide a packaging machine and a method which make it unnecessary to close or cross-seal the packaging tube immediately after the molded tube has run out, to allow a "cold" cut at the tube running off the molded tube and to attach the top-side closure to the separated tube Allow piece of hose before filling the separated piece of hose.

According to the invention, a packaging machine is provided for this purpose, which consists of a tube forming station with a supply of packaging material and with an endless conveyor arranged underneath, to which further processing stations for filling and closing are assigned. A cutting device is arranged under the tube forming station or under its at least one shaped tube, and below this is the endless conveyor, which is provided with tube attaching mandrels at cycle distance. In at least one cycle step distance there is also a closing station behind the tube forming station above the endless conveyor and behind the turning area of the endless conveyor there is a transfer station which is followed by a filling station and a further closing station.

With regard to the method for producing, filling and closing, in particular, narrow tubular bags, a longitudinally sealed tube is initially continuously clocked from a packaging material web during the manufacture of the tubular bag, which is still open on one side, and a tubular piece of bag length is continuously separated therefrom, after which the tubular bag is filled and then is closed. According to the invention, the procedure is such that using an adequately push-resistant and largely form-resettable film for the packaging material when the longitudinally sealed tube is advanced by one bag length, the lower, open end is placed on a cross-section-adapted tube plug-in mandrel and the tube piece is coldly separated from the longitudinally sealed tube , After which the upper end of the hose section is closed in at least one cycle step distance, the hose section is turned upside down, pulled off the hose plug-on mandrel and is closed in a corresponding cycle step distance after at least one filling by transverse sealing.

In this process design according to the invention, the hose formed is not cross-sealed immediately after it has been shaped and longitudinally sealed on the molded tube, but only the hose is pushed and placed on the respective hose plug-in mandrel, with due regard to this sliding and fitting, the use of sufficient "push-resistant""Foil material is essential. Reg. the proviso that the film used should also be "form-resettable" as far as possible, this is understood to mean a film or a film material that the hose pushed off the molded pipe or the hose piece pushed onto the push-on mandrels at least largely after the crushing load when the hose piece is cut off This is particularly important with regard to the subsequent filling process, since when the filling nozzle is centered on the open cross-section of the hose, it has the same distance from the wall of the hose on all sides and therefore wetting with the filling material cannot occur. A clean, contour-accurate cutting of the piece of hose placed on the plug-on mandrel is guaranteed in the present case by the fact that it is not directly below that hot cross seal seam of the subsequent hose piece as with the subject of The aforementioned German patent application DE 44 29 148 AI is cut off with its geometrically imprecise transition from the sealing seam into the actual tube body, ie the section is made on the cross section of the tube which is geometrically precisely defined by the molded tube. In contrast to the method mentioned in the introduction according to the aforementioned German patent application, the first closure of the hose piece does not take place at the bottom end of the packaging, but at the other end, namely away from the molded tube and the deduction requirement associated with the actuating mechanism and requiring a certain amount of time, which means that Closing elements can be assigned stationary to the conveyor line and they only have to execute their respective closing movement. In addition, this closure, which can also be considered as an alternative by means of a tube head piece, takes place when the tube piece is not yet filled, which is always somewhat problematic per se with such tube head closures, since they are generally round or oval.

The use of an endless conveyor, which is also known per se after the above-mentioned German patent application, is of particular importance in the present context insofar as, to a certain extent, this automatically takes over the hose pieces which have been plugged onto the mandrels and are already closed on one side and are only taken over by means of gripping elements for so much time / The path requirement requires that it corresponds to the mandrel height, which is only a small fraction of the length of the hose sections. As a consequence, the method according to the invention also makes it possible to increase the cycle of the packaging machine provided for carrying out the method. The hitherto customary removal of the packaging tube formed by means of transverse sealing jaws arranged directly under the molded tube, which have to move back the entire removal path in order to be able to attach to the tube again and to be able to remove it again, is therefore eliminated. BRIEF DESCRIPTION OF THE DRAWINGS

The packaging machine according to the invention and the associated method, including advantageous advantageous embodiments, can be better understood from the following description of exemplary embodiments in conjunction with drawings, in which

Fig.l shows schematically and in perspective the necessary elements for forming a packaging material web into a tube; 2 shows the packaging machine according to the invention in

Side view; 3 shows the packaging machine according to Fig.l in plan view; FIG. 4 shows a top view of two hose push-on mandrels arranged as a “cycle group” on the endless conveyor; Fig. 5 shows a hose plug-in mandrel in section with the attached piece of hose and the pipe end located above it; FIG. 6 shows an enlarged plan view of the circular part of the conveyor line compared to FIG. 1; Figure 7 shows the conveyor line according to Figure 5 in side view; FIG. 8 shows a side view of another embodiment of the packaging machine and FIG. 9A, B shows schematically and in side view two embodiments of the packaging after passage through a first closing station.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The packaging machine consists of a tube forming station 1 with a packaging material feed 2 and with an endless conveyor 3 arranged underneath, to which further processing stations for filling and closing are assigned. With regard to the tube forming station, reference is made to FIG. 1, which represents a special embodiment insofar as here the packaging material web PB is cut into three strips 10 by schematically illustrated longitudinal cutting knives 100, which over a deflecting shaft 102 is fed to three shaped tubes 103 and formed into three tubes 104 thereon. For the longitudinal sealing, a longitudinal sealing jaw 105 is assigned to each shaped tube 103, which for the sake of simplicity is shown in FIG. 1 only on one shaped tube 103. Also shown only once and schematically is an element 106 for the withdrawal of the formed tube 104 from the shaped tube 103. The cutting device is designated by 4, in which a cross-cutting knife 107 is located (only indicated by dashed lines). Extending below this tube forming station 1 is the final release conveyor 3, on which three tube push-on mandrels 5 are arranged in cycle step distance TD in accordance with the number of shaped tubes 103 in this exemplary embodiment.

Based on this and also with reference to FIGS. 2, 3, it is essential for the packaging machine according to the invention in combination that a cutting device 4 is arranged under the tube forming station 1 described according to FIG. 1 and below this the endless conveyor 3, which, as mentioned above , is provided in step increment TD with hose mandrels 5. In at least one cycle step distance TD, a first closing station 6 is arranged behind the tube forming station 1 above the endless conveyor 3 and behind or under the turning area 7 of the endless conveyor 3 a transfer station 8, which is followed by a filling station 9 and a second closing station 6 '. In the exemplary embodiment of the packaging machine according to FIG. 2, it is otherwise only equipped with two shaped tubes 103 to make it clear that the machine can also be equipped with fewer than three and ultimately also with more than three shaped tubes 103.

The conveyor section 3 'adjoining the endless conveyor 3 with its assigned transfer, filling and closing stations 8, 9, 6' is preferably circular and the conveyor element 10 provided with gripping elements 11 is designed as a circular disk or turnstile 12 in this conveying area (see FIG .3). Gripping elements 11 (see FIG. 7) are arranged on the turnstile 12 so as to be adjustable up and down. These elements 11 are thus functionally and positionally controllable on the Transfer position to the endless conveyor 3, the filling position to the filling elements of the filling station 9 and the closing position of transverse sealing elements of the closing station 6 'adjustable. The position US on the conveying element 10 which results from FIG. 3 and is still unoccupied to the left then serves to eject and convey away the finished and filled packs, as indicated by arrows there.

The procedure that can be carried out with it, regardless of where appropriate. Special constructive designs, runs according to the invention in such a way that, using sufficient slide-resistant film for the packaging material web PB, a longitudinally sealed tube 104 is continuously formed therefrom, the lower, open end 109 of which, when deducted by one bag length, on the cross-section-adapted tube piece holding mandrel 5 put on and the bag length is cut cold by means of the cross-cutting knife 107, after which the upper end of the cut-off hose piece 108 is closed in at least one cycle step distance TD and the hose piece 108 is turned upside down, gripped by the grippers 11 at the closed end, pulled off by the plug-on mandrel 5 and in a corresponding manner Clock step distance TD is closed by cross sealing.

Regarding the "cold separation" mentioned by means of the cutting device 4, it should be pointed out that this is important insofar as the cut edges must not stick or stick together during the separation, ie the open cross-section 109 of the tube piece 108 must be maintained in order to be securely attached to ensure the severed hose section 108 on the respective mandrel 5. This is also important in view of the fact that instead of a simple transverse sealing in the first closing station 6 in the other open cross section 109 'of the tube piece 108, a tube closure shoulder 110 is to be inserted and sealed, as is shown in FIG. 9A, for example. Apart from the advance by means of the elements 106 by the length of a piece of hose 108 on the shaped tube 103, and indeed without the need to reset trigger elements (transverse sealing jaws), the following processing stations 8, 9, 6 'advantageously have only short adjustment paths perpendicular to the conveyor line level for the gripping elements 11 on the conveying element 10 in order to be able to grip the hose pieces 108 to be taken over by the endless conveyor 3 and to bring them to the filling position and closing position to the stations 9, 6 '.

A detailed explanation of the required drive and adjusting mechanisms on the entire packaging machine including the gripper design and controls is unnecessary, since these are design elements and measures that are common in packaging machine construction.

With regard to the configuration of the hose plug-on mandrels 5, reference is made to FIGS. 4 and 5, FIG. 5 also illustrating the plug-on situation on the mandrel 5 under the shaped tube end shown with. As can also be seen from FIG. 5, expandable, resilient elements 13 are arranged on the plug-in mandrels 5, which are conical at least at the free end, in such a way that, on the one hand, the hose end to be pushed in each case can be easily pushed onto the mandrel, but then with a certain radial tension on the mandrel 5 is held securely by the elements 13 by their slight spreading. For this spreading, it is sufficient to pull the mandrel slightly downward in order to submerge the elements 13 and thus to spread them slightly.

In order to be able to rotate the mandrels 5 and thus the attached tube pieces 108 by 90 ° before transfer to the circular conveyor section 3 ', if it is desired to position the second transverse sealing seam perpendicular to the transverse sealing seam 111 previously created in the course of the endless conveyor 3, these are the mandrels 5 rotatably mounted and provided with raster discs 5 'with which and a suitable pin drive causes the 90 ° swivel can be. In the respective rotational position, the mandrels 5 are held by a spring-loaded catch 14, as shown, for example. The above-mentioned pin drive simply consists of a pin 5 "arranged stationary next to the endless conveyor 3 on the machine frame G, which engages in the grooves 5"'' of the raster disk 5 'as it drives past, rotates the raster disk 5' and thus the mandrel 5 by 90 ° and exits from the relevant groove 5 '''after passage.

The circular conveyor section 3 'consists, as mentioned above, of a step-controlled rotatable disk or a turnstile 12 on which the gripper elements 11 are arranged so that they can be moved up and down in a controlled manner.

In the transfer station 8, in which the tube pieces arrive with their closed ends pointing downwards, they move into the already waiting and opened grippers 11, which then pull the tube pieces off the mandrels 5 after access and bring the tube pieces 5 under the filling station 9 , lift this with its open end against a filling funnel T supplied by a dosing device 15 and after filling and lowering again transport it by turning it further under the second closing station 6 'and lift it against the transverse sealing jaws which are in the position there. In this entire range of rotation, i.e. at least up to the second closing station 6 ', correspondingly curved side guides 16 are required for keeping the transported packs upright. If the tube pieces 108 are closed in the first closing station 6 with tube heads 110, the grippers 11 are adapted to their shape accordingly. Side guides 16 for the tube pieces 108, as shown in FIG. 6, are not absolutely necessary in this case.

Instead of designing the second conveyor section 3 'in the form of a turnstile 12, a second, continuously extending endless conveyor 30, as shown schematically in FIG. 8, can also be arranged downstream of the first conveyor section. The transfer station 8 results from the overlap - l ü ¬

of the endless conveyor 3 via the endless conveyor 30, which is also equipped with grippers 11 arranged at a cycle step distance TD. Since these grippers 11, after they have gripped the transverse sealing seams 111 or the tube heads 110 of the hose pieces 108, have to be lowered somewhat in order to pull the hose pieces 108 off the mandrels 5, these grippers 11 are either with a suitable adjusting mechanism in relation to their normal running plane E or the endless conveyor 30 can be moved up and down in the area of the transfer station 8, or it can also, as shown in dashed lines and indicated by arrow P in FIG. 8, make the carrier disk 31 of the endless conveyor 30 movable up and down in the machine cycle by a required amount and be arranged.

Claims

Claims: 1. A packaging machine for producing, filling and closing particularly narrow tubular bags, the bag being filled from a packaging material web after the production of the still open-sided bag and then being sealed, consisting of a tube forming station (1) with a packaging material web feed (2) and with one below it arranged endless conveyor (3), to which further processing stations for filling and closing are assigned, characterized in that a cutting device (4) is arranged under the tube forming station (1) and underneath this the endless conveyor (3), which is in step incremental distance with tube attaching mandrels (5) is provided, and that in at least one cycle step distance behind the tube forming station (1) above the endless conveyor (3) a first closing station (6) and behind the turning area (7) of the endless conveyor (3) a transfer station (8) is arranged in the train a further conveyor section (3 ') and the filling station (9) e further locking station (6 ¹ ) are connected. 2. Packaging machine according to claim 1, characterized in that the hose mandrels (5) are each arranged in groups of at least two mandrels (5) on the endless conveyor (3) and the tube forming station (1) is accordingly equipped with at least two shaped tubes (103). 3. Packaging machine according to claim 1, characterized in that the conveyor section (3 ') adjoining the endless conveyor (3) with its associated transfer, filling and closing stations (8, 9, 6') circular and one with gripping elements (11 ) provided conveyor element (10) in this conveyor section (3 ') is designed as a circular disk or turnstile (12), on which the gripping elements (11) are designed to be adjustable up and down and can thus be controlled in a functional and positionally appropriate manner to the transfer position from the endless conveyor (3) , the filling position of filling elements and the closing position of cross sealing elements are adjustable. 4. Packaging machine according to claim 1, characterized in that the at least at the free end tapered hose plug-on mandrels (5) are uniformly equipped all around with expandable, elastic elements (13). 5. Packaging machine according to claim 4, characterized in that the gripping elements (11) on the conveyor element (10) are pivotally mounted by 90 °. 6. Packaging machine according to claim 1, characterized in that the subsequent to the endless conveyor (3) conveying path (3 ¹⁾ with its associated take-over, filling and closing stations (8, 9, 6 ') and oriented in the same direction, with in relation to the plug-in mandrels (5) located in the transfer station (8) on the up and down movable gripping elements (11) of the endless conveyor (3o) which underlaps the first endless conveyor (3) in the transfer station (8) in an overlapping manner. 7. A method for producing, filling and closing, in particular, narrow tubular bags, wherein initially a longitudinally sealed tube is continuously formed in the course of a production of the tubular bag, which is still open on one side, from a packaging material web, and a tubular piece of bag length is continuously separated therefrom, after which the tubular bag is filled and then closed, characterized in that using a sufficiently push-resistant film for the packaging material when the longitudinally sealed tube is advanced by one bag length, the lower, open end is placed on a cross-sectionally adapted tube plug-on mandrel and the tube piece is coldly separated from the longitudinally sealed tube, after which in At least one cycle step distance, the upper end of the hose section is closed, the hose section is turned upside down, pulled off the hose plug-in mandrel and in a corresponding cycle step distance after filling is closed by cross sealing. 8. The method according to claim 7, characterized in that a form-recoverable film material is used for the slide-resistant film. 9. The method according to claim 7, characterized in that the packaging material lengthways cut into at least two strips of the same width and at the same time formed from each strip corresponding longitudinally sealed tubes and these are simultaneously placed on a corresponding number of tube mandrels driven under them. 10. The method according to claim 7, characterized in that the upper, open end of each tube piece is closed by using a tube head piece and this is firmly connected to the opening edge of the tube piece. 11. The method according to claim 7, characterized in that a transverse sealing seam is attached to the closure of the upper, open end of the tube piece in the first closing station. 12. The method according to claim 11, characterized in that the closure of the upper, open end of the tube piece is carried out by a transverse seal extending transversely to the lower transverse sealing seam.