DE2629099A1 - METHOD AND DEVICE FOR COVERING GOOD STACKED ON A PALLET WITH A COVERING - Google Patents

Description

PATKNTANWAiT

DIPL. ING. K. HOLZES,

PHITIPPINK-WELSEB-STIlASSB 14

8900 AUGSBURG

TBtEFON 51647 5 TELEX 5 33S02 patol d

B.393

Augsburg, June 29, 1976

ANVAR - Agence Nationale de Valorisation de la Recherche 13 Rue Madeleine Michelis, Neuilly-sur-Seine, Haut3-de-Seine,

France

Method and device for coating on a pallet stacked goods with a wrapping

The invention relates to a method for covering in the form of a straight vertical prism on a Pallet of stacked goods with a wrapping, with a heat-weldable one wound flat on a supply roll Covering tube pulled off, then down over a

SQ988S / 03ÖÖ

29099

wedge-shaped, supported on rollers arranged outside the hose expanding body guided, which the hose into a prism shape similar to the prism shape of the goods, then pulled down over the pallet and finally by folding in and heat welding over the good is sealed and cut horizontally over the weld, and a contraction of the the hose section enveloping the good brought about so that the finished casing tightly encloses the goods on the pallet.

Generally, such a wrapping process is carried out using a heat shrinkable wrap, wherein that with a tubular sleeve section that is welded shut and cut off Coated material is passed through a tunnel in which the shrinkage of the envelope is brought about with the help of a stream of hot air, or where one, a horizontal hot air jet generating heating nozzle arrangement vertically from the pallet upwards passes along the entire height of the property. The energy consumption for heating the on the cladding blown air is quite substantial and regulating the temperature at which the hot air is achieved the desired heat shrinkage must be blown out, is essentially dependent on the prevailing environmental

Ö988S / 03Ö

dependent on conditions. In addition, the wrapping of heat sensitive Goods according to this known method not possible.

Stretchable coatings have also been used for wrapping goods, i.e. coatings that are underneath Stretch the tension elastically and seek to return to its original shape after relief. These stretchable covers are, for example, wrapped in a spiral shape with lateral overlap and through with simultaneous application of tension a transverse weld or bond is fixed, or they are stretched and wrapped around the good, after which the two ends of the cover are attached to one another by gluing or welding, in both cases the good during wrapping as a result of the stretching of the Covering exposed to an asymmetrical side load. Furthermore, it is difficult to control the tension of the coating to be controlled so that there is a uniform elongation. In addition, the elastic contraction acts causing the return force on the line connecting the two ends of the cover. Finally, the wrapping not watertight at the top and, if a watertight covering of the goods is required, a watertight one must be used Cover to be attached to the top of the goods.

The invention is based on the object of developing a method of the type set out at the beginning so that no application of heat is required to enclose the goods on the pallet in the envelope. In addition, the item to be wrapped should not be exposed to any asymmetrical lateral loads during wrapping.

In order to achieve this object, such a method according to the invention is characterized in that an elastically stretchable envelope tube is used with a smaller circumference than that of the goods in the unstretched state and that the tube, adapted to the prism shape of the goods, is above the goods on all edges of its Prism shape grasped and circumferentially by horizontal train up to a prism shape similar to the prism shape of the good with a larger circumference than that of the good stretched and, after being pulled over the good in the stretched state, at the same time on all edges ~ is left.

By using the method according to the invention, it spans its prism shape at all edges at the same time When the sleeve is released, the goods on the pallet are uniformly distributed. By pulling in the bisector Planes the edges of the prism shape becomes a uniform one

609885/0300

Tension of the hose ensured, which is why there is a regular containment tension. The tubular one Wrapping shows no weakening of the resistance to the residual strain when the good is wrapped is. Without it being necessary to heat the casing and thus inevitably also the material, all of them result Advantages in terms of tightness and regularity of the envelope, as they are according to the conventional method have been achieved with the help of heat shrinkage »

Advantageously, to grip each edge of the tube prism, are distributed regularly along the edge Grip points these grip points downwards along a plane bisecting the angle in question running path, the first, obliquely from one on the relevant edge of the tube prism located starting point of outwardly extending section and a second, vertically along and with Having a distance outside along the associated edge of the goods prism extending portion. It will the relevant tube prism edge progressively when passing through said starting point through the grip points while pulling the hose downwards taken, and after all the grip points are in the second web section, all the grip points released at the same time.

- 5 -

609885/0306

829093

The tube stretching takes place in terms of cross-section when the grip points pass through the first track section, this stretching during the downward movement of the hose takes place above the goods.

For wrapping goods that are stacked in the form of a rectangular parallelepiped with a given height, width and depth by means of a hose wound flat on a roller, which has two isosceles, inwardly folded double folds that lie between two outer strips with parallel edges, this hose being spread open the inner gap is brought into a rectangular prism shape in cross section, in which the prism edges are formed by the mentioned edges of the two outer strips of the folded tube, the tube material is preferably at least 6% elastically stretchable and the width of the two outer strips and the depth of the two inner gaps are each at least k% smaller than the width and half the depth of the stack of goods.

The rectangular parallelepiped is the most common and most favorable form of the stack of goods for storage. and with this shape the unfolding of the tube and the grasping of the edges of the tube prism occurs through

6G9885 / 03ÖÖ

• τ »

facilitates the presence of the folds which, when unfolded, form these edges. The amount of hose stretch provides a compromise between the stretch desired for the finished enclosure and that required Game for pulling the hose over the property.

The invention also comprises a device for carrying out the method according to the invention, with a frame, which essentially has the shape of a vertical, rectangular parallelepiped and with its lower part a duct forms for the goods stacked on a pallet with a central wrapping position, further with Hose pull-off and guide center that pulls the hose into lead down a vertical center plane of the frame, furthermore with a .Sschlauchspreizkörper in the form of a wedge pointing upwards, the edges of which define the edges of the tube prism and the one outside of the tube arranged rollers is supported, between which and the expansion body the hose passes through, and with a welding and cutting device which is arranged in terms of height between the expansion body and the material and which in turn a pair of heating jaws, between which the hose in of said frame center plane along a horizontal welding line between 3ich can be clamped, two in the called frame center plane effective inward folding wedges

- 7 -

£ 09808/0306

2829099

and has a knife that is displaceable parallel to and above the welding line. This device is according to the invention by four guide rails arranged on the four vertical edges of the frame, each of which has a first vertical plane bisecting the angle of the respective tube prism edge from a starting point on this tube prism edge, and a second section running diagonally downward outward and a second section at a distance the respective associated edge of the goods have vertically running section, further by four chains guided on the guide rails, each of which has chain links arranged at regular intervals, each with a self-locking clamp with a clamp opening element, further by a chain drive that pulls the four chains downwards simultaneously along the guide rails , further by in each case a first, near the starting point of the first section of each guide rail, the forceps opening element actuating the forceps opening element when passing a clamping forceps and a second tong opening device, which extends over the second section of each guide rail, for the simultaneous actuation of the tong opening elements of all clamping tongs _s and through which are located on this guide rail section

609885/0300

a pole control device for the coordinated sequential actuation of the chain drive, the second tong opening device and the welding and cutting equipment.

During their downward movement, the clamps of the chains run at the starting point of the first guide rail section past. The clamping tongs are activated by the first tong opening device as they pass this starting point open and close again by gripping the relevant tube prism edge, which they then pull down. The clamping tongs of each chain run one after the other at the starting point mentioned over, so that the gripping and downward pulling of the respective tube prism edge takes place continuously. the Guiding the chain links along the first guide rail section leads to a circumferential expansion of the hose so that it is guided over the upper part of the goods. During the downward movement along the second guide rail section, the clamping tongs hold the stretched hose at a distance from the material, see above that he can be guided over it without touching the good. When the hose is up over the pallet the good has been pulled, the hose is opened by simultaneously opening all clamping pliers by means of the second

609885 / 03QÖ

2629093 • / to.

Forceps opening device released and cocked closely around the goods on the pallet. Then the hose is coordinated through to the top of the item Actuation of the inward folding wedges and the heating jaws collapsed and through which the collapsed hose between clamped heating jaws welded. Then the hose section enveloping the material is moved by the Knife separated so that on the one hand the wrapped material and on the other hand the free tube for the next good are available. The various work processes are coordinated by a pole control device.

According to a preferred embodiment of the invention, the guide rails each have a magazine section running vertically upward above the first guide rail section, on which the respective chain is located as long as the common chain drive is not in operation. In this arrangement, the chains are each above the first guide rail section in waiting position on the respective magazine sections so that they can grasp the tube prism edges at the height of the expansion body _e

According to a modification of this, the chains each form one

- 10 -

109885/0300

closed loop and are at the starting point of the first Pührungss chienenab section and at the bottom of the second guide rail section over pulleys guided. The chains are on the upward sections of the closed loops in Waiting position, and the guide rail assembly has a reduced height.

The clamping tongs preferably each have a tong body attached to the relevant chain link, which carries a fixed jaw and a movable jaw, the latter being extended by an opening pin is. The first forceps opening device is by one at the starting point of the first section of each guide rail in the path of the opening pin arranged cams formed. The second opening device can be arranged along the second guide rail section extending flexible tube which can be inflated with compressed air via a solenoid valve that responds to an opening signal, whereby the through the inflation expanding tube the opening cones of the Clamping pliers actuated.

The invention is described in more detail below with reference to the accompanying drawings, for example.

- 11 -

6098S5 / 03QÖ

2829099

In the drawings show:

Fig. 1 is a schematic perspective

View of a device according to the invention,

Fig. 2 is a front view of the device,

3 shows a side view of the device,

4 shows the welding and hose cutting

mechanism of the device,

Fig. 5 in perspective as a detail

a chain link carrying a clamp,

6 also shows an organ as a detail

to open the clamping pliers, and

7 is a partial view of a modified one

Embodiment of the invention.

According to the schematic in Fig. 1 and more in detail

- 12 -

60988 5/0300

The embodiment shown in FIGS. 2 and 3 has the Device on a frame 1, which is constructed from metal profiles and is substantially in the shape of a right-angled parallelepiped with vertical edges. the vertical edges of the frame are formed by four angle irons 11-14. The frame 1 forms a Bridge construction that enables goods 2 stacked on a pallet 3 to pass through. In the Representation is the goods in the repackaging position, in which its vertical central axis coincides with the vertical central axis of the frame 1.

Wrapping material in the form of a tube 4 is wound flat on a supply roll 10, which after Kind of a bellows has two inner double folds, which are shown schematically at 4c in the upper region of the frame are visible «, the hose 4 withdrawn from the supply roll 10 is first pulled upwards, then over a first deflection roller 5 and then guided over a second deflection roller 6 into a central plane of the frame 1. The hose then slides over a hose, which has the shape of an upwardly directed wedge unfolding expansion body 7, which is provided with rollers 16, which are mounted on the frame 1 support rollers

- 13 -

609885/0306

prop up. The hose 4 passes between the rollers 16 and 17. After the hose has unfolded 4 Due to the expansion body 7, the hose has the shape of a right-angled prism with two front surfaces 4a and two Side surfaces 4b, the latter being formed by the unfolded double folds 4c.

On the four vertical edges of the frame 1 guide rails 21 to 24 are arranged, each of which has a first obliquely diverging section 21a ... 24a beginning at the level of the lower edge of the guide body 7 unfolding the tube. A second, vertical section 21d ... 24d adjoins each of these first sections 21a to 24a at the bottom. These second sections 21b to 24b run along the edges of the item 2. In addition, the guide rails 21 to 24 each have a magazine section 21c .. _e 24c. These magazine sections 21c to 24c run upwards from the first sections 21a to 24a and are oriented essentially vertically.

The guide rails 21 to 24 each lead a chain 31 ... 34, which consist of successive, respectively chain links carrying a clamp

- 14 -

609885/0300

is. These chain links will be described in detail later. The chains 31 to 34 are with transport ropes 31 'to 34' provided that a simultaneous Allow downward movement of the chains from the magazine sections 21c to 24c until the chains settle on the vertical sections 21b to 24b. The downward trajectories of the chains 31 to 34 along the Guide rails 21 to 24 each contain a first, inclined section, which is at 31a. · <> 34a begins at an edge of the right-angled prism formed by the unfolded tube 4. In the beginning areas 31a to 34a of these first chain track sections are on the starting areas of the corresponding first guide rails From sections 21a to 24a opening cams 41 to 44 arranged, of which only the cam 41 on the guide rail 21 is visible in FIG.

In the middle part of the frame 1 between the expanding body 7 unfolding the hose and the upper end of the goods 2 stacked on the pallet, a welding and cutting device 18, 18 ', 19, 19 ^{f is} arranged, which is shown in more detail in FIG . ^{This welding and cutting device has two jaws 18 and 18 1} arranged in parallel on the two front sides 4 a of the hose prism 4. These cheeks point

- 15 -

6Q988S / 03ÖÖ

heated jaw body 18O or 180 · on, which by means of
Pneumatic cylinders l8l or I8l ^? so operable
and are guided by means of rods 182 and 182 'sliding in guides so that they meet in the central plane of the frame and press the hose 4 together again.

Above the heated pool body 180 is a
Knife 183 arranged, which by means of a not
illustrated pneumatic cylinder is transversely displaceable over the entire length of the jaw body 180. Finally, the welding and cutting device has folding mechanisms 19 and 19 ^f , of which only the
Mechanism 19 is shown. These folding mechanisms each contain a pneumatic cylinder 190 which actuates a two-legged inward folding wedge 191a, 191b, the two legs 191a and 191b of which slide with their free ends in a guide track 192. The chains 31 to 34 each have a number of chain links, each of which carries a clamp. FIG. 5 shows such a chain link 30 which has self-tensioning clamping pliers 300 arranged on an elastic metal plate 301. In each case a row of such plates 301 forms a chain. The self-tightening clamp 300 consists of a
the plate 301 attached pliers body 302 with a

- 16 -

! -09885/0300

■ 4}.

fixed jaw 303 and one by means of a pin 305 on Pliers body 302 articulated movable jaw 3 ° 4, which is urged against the fixed jaw 303 by a torsion spring 307 ivird. One formed integrally with the movable jacket 304 Pin 306 is used to open the clamping pliers 300. To open the pliers, the pin 306 is in the direction of the Arrow 310 moves.

Two rollers 308 and 309 arranged at right angles to one another run on the guide surfaces assigned to them Guide bar 20 and thereby lead the chain. You will determine that the support of the movable jaw takes place on the fixed jaw 303 on the inside of the pliers, so that a gripped between the two jaws hose section increases the forceps clamping force, since the Guide surface 202 of the guide rail 20, the roller 3O8 holds back and the hose is therefore under tension.

Pliers opening organs are located along the vertical second guide rail sections 21b to 24b (FIGS. 1 to 3) 51 to 54 arranged. Such a forceps opening organ is shown in more detail in FIG. 6 and is designated there by 50. It consists of a U-metal rail 500, in which a flexible tube 501 is inserted, which is closed at both ends and with a not

- 17 -

609885/0300

provided inflation mouthpiece is provided. The forceps opening organs run along the vertical second guide rail sections 21b dis 24b and are each arranged in such a way that the pins 306 of the clamping forceps 300 (see Fig. 5) of the chains 31 to 34 transversely in front of the open side of the U-rail 5 ° 0 (Fig. 6) lie. If the chains are 31 to 34 fully along the vertical second guide rail portions 21b to 24b, on inflation of the tube 501, which then assumes the shape illustrated designated 502 chain-dotted lines, the pins 306 (FIG _e 5) of the movable jaws in the direction of the arrow 310 pivoted.

To repackage the goods stacked on the pallet 3, the hose 4 is pulled off the supply roll 10, passes over the guide rollers 5 and 6 and is guided over the expansion body 7 that its two front surfaces 4a are pushed apart and the lateral double folds 4c unfold to form the side surfaces 4b, after which the edges of the two front surfaces form the edges of a right-angled prism. Then the hose passed between the rollers 16 and 17 and after pulled down until the edges of the prism formed by the tube 4 represent the beginning 31a to 34a of the first path

- 18 -

609885 / 030Q

Sections of the chains 31 to 34 reach. The chains 31 to 34 are then along the guide rails pulled down to 24. In the course of this downward pulling of the chains, those on the chain links happen arranged clamping tongs of the chains 31 to 34 one after the other the path starting point 31a ... 34a, the opening pin 306 (see FIG. 5) of each tong over that of the The cam 41 associated with the chain in question runs, as a result of which the tongs open and the two jaws 303 and come to rest on both sides of the respectively adjacent edge of the prism formed by the tube. At the When the pin 306 runs off again from the cam 41, it closes the clamp pliers again and clamps the hose edge between itself, so that the downward movement of the The hose is pulled along with the forceps. During the downward movement of the respectively associated chain link along of the first, inclined guide rail section 21a. «. 24a is the hose 4 at the same time on all four edges pulled apart so that its circumference, which is smaller than that of the in the unstretched state stacked good 2 i3t, is now stretched so that the hose pass over the stacked good 2 can. The chain tracks are in such a way in vertical planes going through the central axis of the 3 frame,

- 19 -

609885/0300

* oto *

that the directions of the elongation tensile forces lie in the planes which bisect the angle enclosed by the tube edges. In the course of the second rail section along the vertical second guide rail sections 21b to 2 4b, the hose is pulled over the stacked goods 2 until it slides over the pallet 3. The chains 31 to 34 are then located completely along the second guide rail sections 21b to 24b, the pins of the clamping tongs 300 lying transversely in front of the inflatable tubes of the second opening elements 51 to 54. Then is blown pressurized air into the inflatable tubes 501, whereby all the clamps are opened simultaneously _o The thus let loose tube prism encloses characterized closely the material 2 located on the pallet. 3

The welding and cutting device 18, 18 ', 19, 19' is then put into operation (FIG. 4). For this purpose, compressed air is fed to the four pneumatic cylinders 182, 182, 190 and 190 «. Thereby, on the one hand by the pneumatic cylinder and 190 ', the folding wedges 191a, actuated 191b 4b at the middle part of the side surfaces to create the tube and the original double folds 4c merge again, and place the other hand, the ^f by the pneumatic cylinder 181 and L8L advanced heated shoe body 180 and 180 ¹ the front surfaces 4a of the hose over the horizontal

- 20 -

609885/0300

Top surface of the stacked goods 2. The gaps 4c are now stamped in the shape of isosceles triangles Between the heated sac bodies 180 and 180 The clamped hose is welded along a horizontal line. Then the knife becomes 183 moved by its pneumatic cylinder along the width of the compressed hose and severed the tube 4 above the weld seam. The good 2 is now enveloped and can after the release by the welding and Cutting device can still be evacuated while the hose 4 is available for repacking the next stack of goods * bar is after the chains 31 to 34 withdrawn onto the magazine sections 21c to 24c of the guide rails have been.

The various individual operations of the wrapping process, i.e. the pulling down of those pulling the hose with it Chains, the actuation of a solenoid valve for the supply of compressed air into the inflatable opening devices for the clamp pliers, the actuation of solenoid valves to act on the pneumatic cylinders 181 pushing the heated jaw bodies forward and to act on them the inward folding performing pneumatic cylinder 190, the control of the welding duration, the actuation of the knife I83 and the retrieval of the chains

- 21 -

609885/0300

629099

the magazine sections of the guide rails, takes place by means of a sequence control unit (not shown) or a program control unit.

Fig. 7 shows schematically a modified embodiment of the invention, in which the chains 31 to 34 each form an endless loop. The guide rails up to 24 have no magazine sections. At the beginning of the inclined, first sections 21a to 24a of the guide rails 21 bi3 24 and at the lower end of the second guide rail sections 21b to 24b, there are guide rollers that allow the chains 31 to move to a waiting position on the upward branch of each loop 31b. .. 34b between the guide rails to 24 and the corner edges 11 to 14 of the frame 1, the welding and cutting device 18 has in this embodiment two heated jaws 180 and 180 ¹ , which at the ends of laterally projecting pairs of holding arms and 184 'are arranged »The holding arms can be rotated about horizontal pivot pins running in the center plane of the frame. In their waiting position shown with solid lines, the jaws 180 and 180 'and the holding arm pairs 184 and 184' form a rectangular frame surrounding the hose. In the welding position shown in dash-dotted lines, the jaws 180 and 180 'clamp the hose underneath

- 22 -

009885/0300

the axis of the trunnions 185 between them. This arrangement provides one over the entire width of the hose continuous weld seam safe. Furthermore, this embodiment allows some reduction in shape the height of the frame, as there are no magazine sections of the guide rails.

, The expandable tube has an elastic extension of more than $ 6, the, if necessary. Greater than $ 20 be _e To the required for coating the expanded tube over the stacked Good game to take into account the circumference of the tube before expansion by at least 4% smaller than the size of the stack of goods. In order to obtain a uniform expansion, the width of the front sides and the depth of the side folds are each in the same ratio by at least four % smaller than the width or half the depth of the stack of goods. Preferably, about two thirds of the expandability is used to span the stack of goods, while the remaining third of the expandability is used to produce the play required to cover the hose over the goods.

Although the embodiment described for example for wrapping stacks of goods in the form of a rectangular Parallelepiped is the invention

- 23 -

609885/0300

Of course, it can also be used for wrapping stacks of goods that are straight and polygonal in cross-section Form prism, in particular with a cross section in the form of an equilateral triangle or regular Hexagon. The hose is again in the form of a prism similar to the prism shape of the stack of goods brought and then by grasping the prism edges in each case in the direction of the edge angle bisector Layers stretched. The wrapping device for execution of the method according to the invention has just as many Chains carrying guide rails and clamps how the prism formed by the material to be enveloped has edges.

609885/0300

Claims (8)

Patent claims j 1.j procedure for coating in the form of a straight vertical prism on a pallet stacked goods with a wrapping, with one flat on a supply roll Coiled, heat-weldable sleeve tube withdrawn, then supported downwards over a wedge-shaped, arranged on outside of the hose rollers Guided expansion body, which brings the hose into a prism shape similar to the prism shape of the goods, then up to Pulled down over the pallet and finally closed by folding and heat welding over the goods and is cut horizontally over the weld seam, and wherein a contraction of the hose section enveloping the material is brought about so that the finished casing tightly encloses the goods on the pallet, characterized in that that an elastically stretchable envelope tube with a smaller circumference than that in the unstretched state of the goods is used and that the tube, which is adapted to the prism shape of the goods, is above the goods at all The edges of its prismatic shape are grasped and, by horizontal pull, circumferentially into one of the prismatic shapes of the goods similar prism shape with larger circumference than that - 25 - 609885 / 030Ö 2623099 of the good stretched and, after the stretching taking place in this state, over the good at the same time all edges are released. 2. The method according to claim 1, characterized in that for gripping the tube prism edges in each case grip points evenly distributed along the edges, these grip points along one in one of the relevant points Tube prism edge bisector plane running path are guided, the first, from a starting point on the associated tube prism edge of obliquely downward outward section and a second, at a distance from the associated edge of the goods has vertically downward section, and that the Tube edges are gripped at the grip points when moving past the web starting point and that all grip points, after they are all in the second web section, are released at the same time. 3. The method according to claim 1 or 2, for coating of well in the form of a rectangular parallelepiped with a given height, width and depth, the flat on the tube wound on the supply roll has two isosceles, inwardly folded double folds, which lie between two outer strips with parallel edges, whereby the hose is opened by spreading the double - 26 - £ 09885/0300 fold is brought into a rectangular prism shape in cross section, the edges of which are formed by the parallel edges of the two outer strips, characterized in that the hose material has an elastic extensibility of at least 6 % and that the width of the two outer strips and the depth of the double folds are each at least k% smaller than the width or half the depth of the goods. 4. Apparatus for carrying out the method according to claim 3, with a frame which is substantially the Has the shape of a vertical, rectangular parallelepiped and with its lower part a duct for forms the goods stacked on a pallet with a central wrapping position, further with hose pull-off and guide means which guide the hose downward in a vertical center plane of the frame a hose expansion body in the form of an upward-pointing wedge, the edges of which are the edges of the hose prism set and which is supported on rollers arranged outside the hose, between which and the hose passes through the expansion body, and with a welding and cutting device, the height-wise is arranged between the expansion body and the material and in turn a pair of heating jaws, between which the hose in said frame center plane length of a horizontal one - 27 - 609885/0300 Welding line can be clamped, has two inward folding wedges effective in the said frame in the center plane and a knife displaceable parallel to the welding line and above the same, characterized by four guide rails (21 to 24) arranged on the four vertical edges of the frame (1), each having a first, in the vertical plane bisecting the respective tube prism edge from a starting point (31a to this tube prism edge obliquely downward outward section (21a to 24a) and a second section (21b to 24a) running vertically at a distance along the respectively associated edge of the item (2) 24b), further by four chains (31 to 34) guided on the guide rails, each of which has chain links (30) arranged at regular intervals, each with a self-locking clamp (300) with a clamp opening element (306), further by one of the four chains at the same time along the guide rails a downward pulling chain drive (31 * to 34 ^f ), further by a first, near the starting point of the first section of each guide rail, each of which activates the tong opening element when a clamping tongs pass, and a second tong opening device (41) each, extending over the second section of each Guide rail extending - 28 - 609885/0300 Forceps opening device (50) for simultaneous Actuation of the pliers opening elements of all clamping pliers located on this guide rails section, and by a sequence control device for the coordinated sequential actuation of the chain drive, the second pliers opening device and the welding and Cutting device (18, 18 ″, 183). 5. Apparatus according to claim 4, characterized in that the guide rails (21 to 24) each a magazine section (21c to 24c) which extends above the first guide rail section (21a to 24a) extends vertically upwards and serves to receive the respective associated chain (31 to 34) before the chain drive comes into operation «, 6. Apparatus according to claim 4, characterized in that that the chains (31 to 34) are each designed as a closed loop and have one at the beginning of the first guide rail section (21a to 24a) and a deflection roller arranged at the lower end of the second guide rail section (21b to 24b) are led. 7. Apparatus according to claim 5 or 6, wherein the clamping tongs each have one on the associated chain link - 29 - 609885/0300 2829099 -3ο have attached pliers body with a fixed jaw and a movable jaw articulated thereon, which latter is extended by an opening pin, characterized in that the first tong opening device one at the beginning of the first guide rail section (21a to 24a) in the path of the Opening pin (306) of the clamping tongs (300) arranged Has cams (4l). 8. Apparatus according to claim 7 »characterized in that that the second forceps opening device each have one along the second guide rail section (21b to 24b) extending flexible tube (501) which via a solenoid valve responsive to an opening signal inflatable with compressed air X3t and when inflated, the opening pin (306) of the located along this second Pührungs rail section Clamping pliers (300) actuated. - 30 - 603885 / 030Q Blank