EP0439789B1 - Method and device for making, filling and closing bags - Google Patents

Description

The invention relates to a method for producing, filling and closing sacks starting from a flat-lying, preferably with side gusseted tubular film web made of thermoplastic material, in which the respectively leading end of the tubular film web is provided with a transverse weld seam and a section forming an open sack is separated from the tubular film web and in which the sack is then filled and the open side of the sack is pulled taut and closed by a transverse weld seam, and a device for carrying out this method.

From EP A-0 290 879 a method and a device of this type is known, with which bags can be manufactured, filled and closed with great power, because a device for manufacturing bags is followed by a filling and closing device, so that the output essentially depends only on the times of filling of the individual bags, because the head weld seams with which the filled bags are closed are carried out during the transport of the bags from the filling station. Because of its high performance, the known device is relatively complex, so that its investment costs are only worthwhile if it is operated predominantly at its full performance can be.

From DE-A-1 586 248 a method and a device for the manufacture and filling of bags are known, in which a tubular film web is pulled forward from a supply roll by a section length corresponding to a bag length in such a way that the tubular film web is held by clamping jaws and one on it at the front end carrying a roller and a crank-driven rocker arm pulls the tubular film web into a loop. As the crank returns, the jaws open and the length of hose that has been removed is transported between the welding jaws and a cross cutting knife. The clamping jaws then close again and the welding jaws provide the advanced tubular section with a cross weld. The hose section separated from the cross-cutting knife is gripped by two grippers at the raised edges of the opening and transported by the cross-cutting knives under the filling funnel, so that pivoting jaws arranged under the filling funnel with clamping devices for holding the sack can move into the opened sack. The type of closing of the filled bags and their removal have not been described in DE-A-1 586 248.

The object of the invention is to propose a method and a device of the type specified at the outset, according to which sacks can be produced and filled with little mechanical effort.

According to the invention, this object is achieved in a method of the generic type by the characterizing features of patent claim 1. The method according to the invention can therefore be carried out with less expenditure on the device, because both for the formation of the bottom weld seams and of the head weld seams only a single welding station needs to be provided. This simplified procedure results from the fact that after the bottom weld seam has been formed, the section forming the sack to be filled is pushed through the opened welding jaws before it is separated from the tubular film web, so that it is gripped by the gripper pairs in the region of its opening edge and moved by them into the filling station and then for the execution of the head

Closure weld seam is transported back to the welding station so that no separate welding stations have to be provided for the execution of the bottom weld seams for the production of the bags and for the attachment of the closure weld seams on the head side after the bags have been filled.

The pair of grippers can translate the sacks seized by them between the welding station and the filling station, which, however, means that the filled sacks would have to be returned to the welding station standing upright. It is more advantageous to pivot the sack after it has been filled from its vertical filling position into an inclined position, in which it is then provided with the head weld seam closing it. With this method, the pair of grippers perform a corresponding swiveling movement.

It is particularly advantageous that the closed sack in its inclined position, in which it is supported on a support device, is released in such a way that it slips onto a conveyor device that transports it away. The filled sack can thus be released from the welding station after the top sealing weld has been made in such a way that it leaves the welding and filling station as a whole, so that the latter is free for the manufacture and filling of the next sack.

A device for carrying out the method according to the invention with a pair of grippers which grasp the sacks in the region of their opening edges from the outside on the side regions, the grippers of which cooperating jaws can be moved towards and away from one another in the central plane of the sack, with a filler neck and with a welding device which by pulling the grippers apart and thus opening edges of the filled sacks lying on top of each other Closes cross welds, is characterized according to the invention by the characterizing features of claim 2.

In the filling station, the grippers of the pair of grippers move towards one another in such a way that the opening edges of the sack held by the pair of grippers can be pulled apart, for example by suction cups. A filler neck that can be raised and lowered in the filling station can then be inserted into the sack opened in this way.

In order to be able to carry out the bottom and head welding seams with a welding device according to a particularly advantageous embodiment of the invention, the welding device can be moved between two positions in which it carries out the bottom welding seam on the one hand and the head welding seam closing the bag on the other hand. This mobility of the welding device takes into account the fact that the head weld seam closing the filled bag must be carried out at a lower point than the previously welded bottom weld seam. The welding device is expediently pivotably mounted in the machine frame and provided with a drive which pivots it between the two positions.

In a further embodiment of the invention it is provided that the sack is supported on a pivoting device in the machine frame, by means of which it can be pivoted from its vertical filling position into an inclined position in which the tightly drawn opening edges in the welding station can be provided with the head weld seam. The support device can consist of side support plates or a side support grate and support arms pivotable relative to these, which support the bag bottom. The support arms can have longitudinal gaps between the strip-shaped support plates or rust bars enforce and be movable in the longitudinal direction for adjustment to different bag lengths.

According to a preferred embodiment of the invention, it is provided that the pair of grippers and the support device are arranged in a frame which, when the cross-welding jaw pair of the welding device is arranged in a stationary manner, can be raised and then lowered again to carry out the head weld. The frame carrying the pair of grippers and the supporting device can be raised and lowered in a simple manner by being supported on a shaft which can be pivoted via pivotable levers. The levers pivoting the frame can be designed as an angle lever, wherein a piston-cylinder unit for pivoting the frame can be articulated on the second lever arm. The frame can form a four-bar system with the piston-cylinder unit provided for the purpose of moving the bags between the welding and filling station, so that a simple pivoting essentially in terms of height and moreover is ensured between the welding and filling stations. Since the same welding device first performs the bottom weld seam on the intermittently supplied tubular film web and then executes the top weld seam on the bag after pivoting and filling, the tube web must be retracted a little by appropriate control of the pair of preferred rollers during the execution of the top seam of the filled bag so that the bottom weld seam temporarily from the area of the cross welding device.

According to a further advantageous embodiment of the invention, the welding device can also be made stationary if it is provided with two cross-welding devices offset in height, the upper of which is the bottom weld seams and the Make the bottom butt welds. A cutting knife is expediently connected to a welding jaw of the upper cross-welding device, which cuts off the leading tube section, which is already provided with a bottom welding seam, from the tube path by executing a bottom weld seam. The two cross welding devices are provided with special control devices so that they can be operated alternately.

The support arms are expediently provided with a vibrating drive, which ensures that the bags are filled tightly in the filling station. The vibratory drive can be identical to the swivel drive of the support arms, the drive expediently consisting of a piston-cylinder unit which is vibrated with pressure medium on the one hand and on the other hand serves as a swivel drive.

In a further embodiment of the invention it is provided that the support arms are mounted with their pivoting and vibrating drive in a support part which can be moved longitudinally relative to the support plate or grate bars. A spindle drive can be provided for moving the supporting part. However, if the support arms for attaching the head welding seams of the filled sacks are to be moved upwards in cycles, a piston-cylinder unit is expediently provided as the drive.

In a further embodiment of the invention it is provided that the pair of grippers and the support device are arranged in a frame which is pivotally mounted in the machine frame and is provided with a pivot drive. The pairs of grippers are additionally provided with drive devices for opening and closing their jaws and for moving towards and away from one another.

An intermittently drivable pair of preferred rollers can be stored in the machine frame, which pulls the tubular film web in each case by a section length. The tubular film web can be pulled off a supply roll.

In a further embodiment of the invention it is provided that a pair of clamping jaws is arranged in the machine frame between the pair of preferred rollers and the welding device, which clamps the front end of the tubular film web when a section of sack is separated from it by a cross-cut.

Each welding jaw of a pair of welding jaws can be fastened to a lever which is pivotably mounted on the frame via parallel link pairs, which in turn is pivotably mounted in the machine frame. The lever then forms a coupling which can be pivoted essentially parallel to itself via a four-bar system.

In a further embodiment of the invention, a lever carrying a welding jaw can be provided with a groove or a counter knife for a cutting knife, which is attached to a lever which is mounted on the swivel frame via parallel link pairs. The cross-cutting knife then executes the cross-cutting cut separating a sack in the area of the welding bars.

According to the invention, the top and bottom weld seams of a sack are essentially made in one place during its manufacture and after its filling, so that only one welding station has to be provided. The bags produced and to be filled are gripped by a gripping device before filling and are not released by this gripping device until after the bags have been filled sealing head welds have been carried out. This enables high quality weld seams to be made.

The welding device is located above the gripping device, so that both the bottom and the head welding seams can be formed with the same welding device.

Fig.1

eine Seitenansicht einer Vorrichtung zum Herstellen, Befüllen und Verschließen von Säcken mit abgehobener vorderer Gestellwand nach Vorschieben einer mit einer Bodenschweißnaht versehenen Schlauchfolienbahn durch die Schweißbacken und Festklemmen des oberen Randbereiches eines abgetrennten Sackes in schematischer Darstellung,

Fig.2

eine der Fig.1 entsprechende Darstellung der Vorrichtung mit in der Füllstation befindlichem gefüllten Sack,

Fig.3

die in Fig.1 dargestellte Vorrichtung in einer Stellung, in der der gefüllte Sack mit seinen aufeinanderliegenden Öffnungsrändern in die Schweißstation zum Anbringen der Kopfschweißnaht zurückgeschwenkt ist,

Fig.4

eine vergrößerte Seitenansicht der den Sack stützenden und verschwenkenden Einrichtung mit dem die Öffnungsränder der Säcke ergreifenden Greiferpaar,

Fig.5

eine Draufsicht auf die Vorrichtung nach Fig.4,

Fig.6

einen Schnitt durch die Einrichtung längs der Linie VI-VI in Fig. 4,

Fig.7

eine der Fig.4 entsprechende Darstellung einer geänderten Ausführungsform der Vorrichtung, bei der der das Greiferpaar und die Stützeinrichtung tragende Rahmen auch der Höhe nach verschwenkbar ist, so daß auf eine bewegliche Querschweißeinrichtung verzichtet werden kann,

Fig.8

eine der Fig.5 entsprechende Darstellung der geänderten Vorrichtung nach Fig. 7,

Fig.9

eine der Fig.1 entsprechende geänderte Ausführungsform, bei der jedoch die Querschweißeinrichtung stationär angeordnet und parallel zueinander zwei Querschweißeinrichtungen vorgesehen sind,

Fig.10

die Vorrichtung nach Fig. 9, bei der ein Sack in die Füllstation verschwenk ist und

Fig.11

die Vorrichtung nach den Fig. 9 und 10 in einem Zustand, in der der gefüllte Sack zum Anbringen der Kopfschweißnaht zurück in die Schweißstation verschwenkt ist.

An embodiment of the invention is explained below with reference to the drawing. In this shows

Fig. 1

1 shows a side view of a device for producing, filling and closing sacks with the front frame wall raised after advancing a tubular film web provided with a bottom weld seam through the welding jaws and clamping the upper edge region of a separated sack in a schematic representation,

Fig. 2

1 shows the device corresponding to FIG. 1 with the filled sack located in the filling station,

Fig. 3

1 in a position in which the filled sack with its opening edges lying on top of one another has been pivoted back into the welding station for the application of the head weld seam,

Fig. 4

2 shows an enlarged side view of the device supporting and pivoting the bag with the pair of grippers gripping the opening edges of the bags,

Fig. 5

a plan view of the device of Figure 4,

Fig. 6

a section through the device along the line VI-VI in Fig. 4,

Fig. 7

4 shows a representation of a modified embodiment of the device, in which the frame carrying the pair of grippers and the support device can also be pivoted in height, so that a movable cross welding device can be dispensed with,

Fig. 8

5 shows a representation of the modified device according to FIG. 7,

Fig. 9

1 shows a modified embodiment corresponding to FIG. 1, but in which the cross-welding device is arranged in a stationary manner and two cross-welding devices are provided parallel to one another,

Fig. 10

9, in which a sack is pivoted into the filling station and

Fig. 11

the device according to FIGS. 9 and 10 in a state in which the filled bag for attaching the head weld seam is pivoted back into the welding station.

In the device shown in the drawing, a pair of preferred rollers 1 is mounted in the side frame walls of a machine frame, of which only the rear side frame wall 2 is shown. By means of this pair of preferred rollers 1, the tubular web 4 guided over the deflection roller 3 can be advanced. In the direction of transport just behind the pair of preferred rollers 1 is a cross member 5 mounted in the side frame walls, which carries a clamping jaw 6. The counter jaw 7 belonging to this jaw 6 is in turn fastened to a crossmember 8 which is held on the arms 9 in its two end regions. The latter are fixed on a shaft 10 which is rotatably mounted in brackets 11. These are firmly connected to a cross member 12. In order to be able to pivot the arms 9, a lever 13 is placed on the shaft 10, to which the piston of a piston-cylinder unit 14 engages, the cylinder of which is connected via a bracket 15 to a profile 16 connecting the two side frame walls. All the details described above are stored in the side frame walls.

Furthermore, each side frame wall 2 is assigned an approximately C-shaped plate 17, which are connected to one another via the square profiles 18 and 19 and via the U-profile 20. The C-shaped plates 17 connected to one another in this way rest on an axis 21, which in turn is firmly connected to the side frame walls 2. In order to be able to pivot the two C-shaped plates 17 about this axis 21, a piston-cylinder unit 22 is provided, the piston rod 23 of which is pivotally connected to the head part of one of the C-shaped plates and the cylinder 24 of which is connected to a bracket 25. This bracket 25 is welded to a U-beam 26, which is firmly connected with its end faces to a side frame wall 2.

In the head-side part of the C-shaped plates 17, a piston-cylinder unit 27 is pivotally connected to each of the plates, the piston rod of each piston-cylinder unit 27 engaging at one end of an angle lever 28. The end of the angle lever 28 facing away from the piston rod of the piston-cylinder unit is connected in an articulated manner to a lever 30, which is also articulated via an arm 31 to the head part of the C-shaped plate 17 connected is. A cross member 32 is welded to both levers 30, only one of which is shown in FIG. 1, and has a recess 33 and a welding jaw 34 at its front end. In the position shown in FIG. 1, a knife 35 engages in this recess 33 and is mounted on a cross member 36. This cross member 36 is held at its end portions by an arm 37, each arm being supported by levers 38 and 39. The lever 38 is articulated on the one hand to the C-shaped plate 17. The other arm 39 is designed as an angle lever which is pivotally mounted at its knee point 40 on the C-shaped plate 17 and is articulated at one end to the arm 37 and articulated at the other end to the piston rod 41 of a piston-cylinder unit 42. The cylinder 43 of this piston-cylinder unit 42 is connected to the square profile 18 via a bracket 44. Like the cross member 32 for the welding jaw 34, the cross member 45 is also mounted, the lever 48 being designed as an angle lever which can be pivoted about its knee point 50 via a piston-cylinder unit 49.

The right half of FIG. 2 shows that the tubular web 4 is clamped in its front region by the clamping jaws 6 and 7, which were previously opened, so that the web 4 could be advanced through the feed rollers 1, guided over the rake 51. The piece of hose protruding over the jaws 6 and 7 is then provided with a bottom seam by the welding jaws 34 and 46, whereupon the welding jaws then pivot back and the jaw 7 opens. The web 4 is then advanced until its bottom seam 52 has reached the lower position in FIG. 1. In order to ensure proper guiding of the freely advanced end of the tubular film web 4, a guide rod 99 is provided, which is arranged transversely at the front end of a longitudinally displaceably guided in the machine frame, which of the Pressure medium-piston-cylinder unit 100 can be pushed back and forth in the direction of the double arrow. After the front section of the tubular film web 4 has reached its position shown in FIG. 1, the jaw 7 as well as the welding jaws 34 and 46 and also the knife 35 are moved into the position shown in FIG. 1. The bag 53 thus formed, which is provided with a bottom seam 52, is held in its upper region by pairs of lateral jaws 54 and pivoted by pivoting these lateral jaws and the support plates 55 under the filler neck 56, where it is then attached and filled in a manner known per se to the filler neck becomes. This filling position is shown in Figure 2. After filling, the full sack 53 is pivoted back into the position shown in FIG. 3 by a pivoting device, which also includes the support plates 55 and which will be described in more detail below. As soon as the sack has reached the position shown in FIG. 3, the two interconnected C-shaped plates are pivoted counterclockwise to a small extent by the piston-cylinder unit 22 so that the upper one is removed by the two welding jaws 34 and 46 the lateral clamping jaws 54 can be welded upward reaching head region 57. Thereafter, the welding guns 34 and 46 open as well as the lateral jaw pairs 54, so that the filled sack 53 can slide over an intermediate plate 59 onto a conveyor belt 60 arranged below after the vibrating plates 58 have been pivoted away. The system is then in the starting position shown in the right half of FIG. 2, with no sack then being in the filling station.

The pivoting device by means of which a sack 53 can be moved back and forth is shown in more detail in FIGS. 4-6 and will be explained in the following. Three transverse square profiles 61, 62 and 63 are together on their Front areas connected via a vertical support 64. The support plates 55 already mentioned in FIGS. 1-3 are fastened to the two upper square profiles 61 and 62. The vibrating plates 58 protrude to the left through the two gaps between the support plates 55 (FIG. 4), the vibrating plates 58 being firmly placed on a shaft 65 in their rear region. This shaft 65 is rotatably supported in a frame 66. The two shaft ends 65 protrude outwards from the frame 66, a bearing block 67, each having an arm 68, being firmly attached to these two shaft ends. The arms 68 are connected to one another via a rod 69, to which the piston rod 70 of a piston-cylinder unit 71 engages. Via the piston-cylinder unit 71, vibrating plates 58 can be pivoted from the position shown in FIG. 4 in the counterclockwise direction (arrow direction A) to such an extent that they lie behind the supporting plates 55, so that a bag 53 filled in the meantime slips onto the conveyor belt 60 can. The piston-cylinder unit 71 serves not only to hold the sack during the filling process, but also to shake the sack so as to compress the filled material.

In order to be able to adapt the height of the vibrating plates 58 to the desired sack format, the frame 66 (FIG. 6) can be displaced in height. For this purpose, frame parts 72 and 73 are connected to the square profile supports 61 and 62, of which two guide rods 74 and 75 as well as a threaded spindle 76 are held. Between the two frame parts 72 and 73, the frame 66 is provided, which is guided through the two guide rods 74 and 75 and can be raised and lowered by means of the spindle 76. For this purpose, the frame 66 has threaded nuts, not shown, in which the threaded spindle 76 engages. The latter is by a frame 73 held motor 77 drivable.

In Figure 4 it is shown that with the two vertical supports 64 to the front, that is to the left projecting profiles 78 and 79 are connected, which frame parts 80 and 81 carry. A piston-cylinder unit 82 or 83 is pivotally connected to each frame part 80 or 81, the piston rod of each piston-cylinder unit acting on the end of an angle lever 84. The angle levers 84 are articulated to the frame parts 80 and 81 at the knee point 85. These angle levers 84 and further links 86 carry bearing blocks 87 which, due to their mounting, are pivoted back and forth in the direction of arrow B (FIG. 5) via the piston-cylinder units 82 and 83, and thus the side areas of a bag 53 via the lateral jaw pairs 54 to be able to move against each other so that the filler neck (Figures 1-3) can move into the sack thus opened. After the filler neck 56 has been extended, the two pairs of clamping jaws 54 move apart again, so that the upper sack area is tightened and thus closed.

As can be seen in FIG. 4, each pair of jaws 54 consists of two jaws 54 'and 54'', each jaw being fastened to a pivot lever 88 and 89, respectively. The pivot lever 88 is pivotally connected to the bearing block 87 at points 90 and the pivot lever 89 at points 91. The two pivot levers 88 and 89 are connected to one another via a coupling 92 in such a way that the pivoting movement of the lever 88 is transmitted to the lever 89. For the purpose of pivoting, ie for the purpose of opening and closing a pair of clamping jaws 54, a piston-cylinder unit 93 is provided, the cylinder 94 of which is pivotally connected to the bearing block and the piston rod 95 of which is articulated to the pivot lever 88.

So that the system described above can be pivoted, the two lower cantilevered profiles 79 are connected to one another in the area facing away from the square profile carrier 63 via a square tube 96 which has end-side pins 97 and 98. These pins 97 and 98 are rotatably supported in the two side walls 2. By means of the two piston-cylinder units 101 and 102, which are fastened on the one hand to the side walls 2 and on the other hand to the frame parts 80 and 81, the entire device, as shown in FIGS. 4-6, can be pivoted.

In the embodiment according to FIGS. 7 and 8, the frame 61, 62, 63, 64, 79, 80, 81 carrying the gripper pair 54 and the support device 55, 58 can be pivoted via the support pins 97, 98, which form a pivot shaft, as it were, mounted on the levers 105, 106, which in turn are pivotally mounted on the pins 107, 108 fixed to the frame. The levers 105, 106 are designed as angle levers, the piston rods of the piston-cylinder units 109, 110 pivotably mounted in the frame being articulated on the free ends of the further lever arms.

The frame 61, 62, 63, 64, 79, 80, 81 is additionally held in the frame by the piston-cylinder units 101, 102, which pivot it about the support pins 97, 98 between the welding station and the filling station. The frame thus forms, with the articulation points of the levers 105, 106 and the piston-cylinder units 101, 102, a four-bar system, so that it can be pivoted both vertically and laterally by the piston-cylinder units 109, 110 on the one hand and 101, 102 on the other hand. Since the frame according to FIGS. 7 and 8 can be pivoted essentially in height via the piston-cylinder units 109, 110, the bottom weld seams and the head weld seams can be attached to the pivotability of the frame Welding device can be dispensed with. Because in order to be able to carry out the bottom and head weld seams at different heights, it is now possible to pivot the height of the frame carrying the bags. However, in order to be able to carry out the head weld seam with the device according to FIGS. 7 and 8 after the frame has been pivoted back from the filling station into the welding station, it is necessary to pull the end of the tubular web a little back from the area of the welding device.

A further exemplary embodiment can be seen in FIGS. 9 to 11, in which there is no pivoting of the welding device and no mobility of the device carrying the sack, so that both the device pivoting the sack and the arms carrying the welding devices directly on the Rack walls are stored.

The levers carrying and pivoting the welding jaws are mounted directly on the side frame walls. In addition, the cross member carrying the welding jaws is provided with two welding jaws 111, 112 running parallel and at a distance from one another. A cutting knife 113, which is fastened to the upper welding jaw 114, which is carried by a cross member 45, can dip into the space formed between these two welding jaws. The cross member 36, which was designed as a knife carrier according to the exemplary embodiment according to FIGS. 1 to 3, has a welding jaw 115 arranged in this embodiment, which cooperates with the welding jaw 112.

The upper welding jaws 111, 114 form the bottom weld seam of the next bag at the respective free end of the tubular path, the preceding bag being separated by the cutting knife 113 below the cross weld seam.

9 shows a sack which has just been formed and which has been gripped by the gripper 154 on both sides of its upper opening edge.

10 shows the sack pivoted into the filling station and filled there.

11 shows the sack pivoted back into the welding station during the welding of the head weld seam closing the sack by the welding jaws 112, 115.

Claims (19)

1. A method for manufacturing, filling and closing bags (53), starting with a flat-lying tubular film web (4) of a thermoplastic synthetic material, preferably provided with side folds,
   wherein the respective leading end of the tubular film web (4) is provided with a transverse weld seam (52), and a section forming an open bag (53) is separated off from the tubular film web (4) and
   wherein the bag (53) is then filled and the open side of the bag is pulled taut and is closed by a transverse weld seam,
   characterized in that
   after the transverse weld seam (52) at the end has been formed, the tubular film web (4) is pushed through the opened welding jaws (34, 46) of the welding station by one section length, and the bag (53) formed in this way is laterally gripped from the outside in the zone of its side edges by a gripper pair and is separated off from the tubular film web (4) above the gripper pair (54) by a transverse separating cut, that the bag (53) held beneath its opening edge on both sides of its opening side by the gripper pair (54) is carried by the latter into the filling station wherein the grippers (54) of the gripper pair (54) move towards each other to open the bag (53), and that after the bag has been filled, the grippers (54) of the gripper pair pull the opening edges of the bag (53) taut and move it back into the welding station wherein the opening edges of the bag that project over the gripper pair (54) are joined to each other by a transverse weld seam.
2. A method according to claim 1, characterized in that after having been filled, the bag (53) is tilted from its vertical filling position (Figure 2) into a slanting position (Figure 3), wherein it is provided with a top weld seam closing it.
3. A method according to claim 2, characterized in that the closed bag (53) in its slanting position, wherein it is supported on a supporting device (55, 58), is released in such a way that it slides onto a conveyor device which carries it away.
4. An apparatus for operating the method according to claim 1, with a gripper pair (54) gripping the bags (53) from the outside in the zone of their opening edges in their side zones, whose grippers consisting of cooperating jaws are movable towards and away from each other, with a filler pipe (56) that can preferably be raised and lowered and a welding device (34, 46) which closes the opening edges of the filled bags by transverse weld seams, which edges have been pulled taut by the movement of the grippers of the gripper pair (54) away from each other, and which, because of this, bear on each other,
   characterized in that
   a drawing roller pair (1) is arranged above the welding device (34, 46) which pushes the tubular film web (4), after a transverse weld seam (52) has been formed at their leading end, by approximately one section length through the opened welding jaws (34, 46),
   that above the gripper pair (54), between it and the welding jaws (34, 46), there is arranged a cutter (35) which separates bag sections from the tubular film web (4),
   that the gripper pair (54) can be moved between the welding jaws (34, 46) into a filling station for the purpose of filling the bag (53) and subsequently back to the welding jaws (34, 46) for the provision of the top weld seam.
5. An apparatus according to claim 4, characterized in that the welding device (34, 46) can be moved between two positions wherein it executes on the one hand, the bottom weld seam (52) and on the other hand, the top weld seam that closes the bag (53).
6. An apparatus according to claim 5, characterized in that the welding device (27 to 46) is pivotably mounted in the machine frame (2) and is provided with a drive (23, 24) which tilts them between the two positions.
7. An apparatus according to one of claims 4 to 6, characterized in that the bag (53) is supported on a supporting device (55, 58) that is pivotably mounted in the machine frame (2) by means of which it can be tilted from its vertical filling position (Figure 2) into a slanting position (Figure 3), wherein its pulled taut opening edges can be provided with the top weld seam in the welding station.
8. An apparatus according to claim 7, characterized in that the supporting device consists of lateral supporting faces (55), or a lateral supporting grid and supporting arms (58) that are pivotable relative to the latter, which support the bottom of the bag.
9. An apparatus according to claim 8, characterized in that the supporting arms (58) pass through longitudinal gaps between the bar-shaped supporting plates (55) or the grid rods and can be moved in their longitudinal direction to be adjusted to different bag lengths.
10. An apparatus according to claim 7, characterized in that the gripper pair (54) and the supporting device (55, 58) are arranged in a frame (61, 62, 63, 64, 79, 80, 81) which, when the transverse welding jaw pair of the welding device is arranged to be stationary, can be raised and subsequently lowered again.
11. An apparatus according to claim 4, characterized in that the welding station is provided with two transverse welding devices (111, 114, 112, 115) in an offset height arrangement, the upper (111, 114) whereof executes the bottom weld seams and the lower (112, 115) the top weld seams for closing the bags.
12. An apparatus according to claim 8, characterized in that the supporting arms (58) are provided with a vibratory drive.
13. An apparatus according to claim 8, characterized in that the supporting arms (58) are mounted with pivoting and vibratory drive (65, 68, 70, 71) in a supporting member (66) which can be moved longitudinally relative to the supporting plate (55) or the grid rods.
14. An apparatus according to claim 13, characterized in that for the displacement of the supporting member (66), provision is made for a screw spindle drive (76, 77).
15. An apparatus according to claim 7, characterized in that the gripper pair (54) and the supporting device (55, 58) are arranged in a frame (61, 62, 63, 64) which is pivotably mounted in the machine frame (2) and is provided with a pivoting drive (101, 102).
16. An apparatus according to one of claims 4 to 15, characterized in that in the machine frame (2), there is mounted a drawing roller pair (1) that can be driven intermittently.
17. An apparatus according to one of claims 4 to 16, characterized in that a clamping jaw pair (6, 7) is arranged in the machine frame between the drawing roller pair (1) and the welding device (34, 46).
18. An apparatus according to one of claims 4 to 17, characterized in that each welding jaw (34, 46) of a welding jaw pair is mounted on one lever (30, 37) each which is pivotably mounted on the frame (17) by means of parallel rod pairs, which frame is, for its part, pivotably mounted in the machine frame (2).
19. An apparatus according to one of claims 4 to 18, characterized in that a lever (30) carrying a welding jaw (34) is provided with a groove (33) or a counter-knife for a cutter (35) which is mounted on a lever that is mounted on a pivoting frame by means of parallel rod pairs (47, 48).

Images