DE2418233A1 - Thermoplastic film bag manufacture - has cutter and welding beam providing transverse seam immediately preceding cut - Google Patents

Abstract

Appts. for mfg. and stacking thermoplastic film bags comprises a cutter-welder consisting of two relatively movable welding beams and immediately behind this a stacker with a device for welding each new bag to the previously stacked bag. The stacker includes a bag-clamping bar which moves by menas of counter spring and which has pins for stacking the bags, and a pressure bar for transfering individual bags into the stacking position. The stacker is independent of the cutter-welder. The welder is separate from the cutting blade and is in the form of units connected together for common movement, another unit including the cuting blade and stacking pins.

Description

Device for making and stacking bags or the like.

Packaging made from thermoplastic plastic film (addendum to patent application P 22 36 523.7-27).

The subject of patent application P 22 36 523.7-27 is a device for the production of bags or the like.

Packaging made of thermoplastic plastic film and stacks of Bag to form a block with a sealing bar consisting of two mutually movable sealing bars Separation and welding device for separating individual bags from a film tube, as well as with a stacking device arranged directly behind it in the direction of passage, those with a device for welding each newly attached bag previously stacked bag of the bag block is provided, with the stacking of the bags takes place with the help of a movable bag clamping strip by geqenfederkraft and a movable pressure strip to transfer the individual bags into the stacking position is provided, the bag clamping strip, the pressure strip and the rest Parts of the stacking device including the welding device to the Welding of each newly delivered bag with the bag stack in its arrangement and function of the separating-welding device are independent and the bag clamping strip is provided with pins for stacking the bags, which are associated with the pressure strip The clamping surface of the bag clamping strip protrudes.

The device described above is advantageously provided to bag to weld and at the same time to separate with the welding, this by means of a welding wedge can be done.

The present invention is based on the object, the basic principle the solution according to the older application in the t7eise to improve that bag with a transverse weld and separation lying next to the weld can, but it is also possible to remove the bag by turning off the heating of the The welding bar can only be separated by a knife, the device also to be converted in such a way that the welding bar can be omitted and only a cutting is to take place with a knife. At the same time, the task is assumed the loosening of the bags opened on the pins, which are combined to form a bag block and optionally also welded to one another, from the stacking and holding device to simplify.

To solve this problem, in a device for manufacturing of bags or the like. Packaging made of thermoplastic plastic film and stacks the bag to one Block, with one of two movable towards each other Sealing bar existing separating-sealing device for separating individual bags from a film tube, as well as with one in the direction of flow immediately behind it arranged stacking device, which is equipped with a device for welding each The newly attached bag is provided with a previously stacked bag from the bag block is, the stacking of the bags with the help of a movable by counter spring force Bag clamping strip takes place and for transferring the individual bags into the stacking position a movable pressure strip is provided, the bag clamping strip that Pressure bar and the other parts of the stacking device including the welding device for welding each newly delivered bag to the stack of bags in their arrangement and function are independent of the separating welding device and the bag clamping strip is provided with pins for stacking the bags, which are associated with the pressure strip Clamping surface of the bag clamping strip protrude, proposed according to the invention that the welding device and the cutting device separated in the form of a cutting knife, however, assemblies are connected to move together and the cutting knife and the stacking pins are present in an assembly.

This proposal ensures that when the Heating of the welding device this becomes ineffective and as a functional unit only the cutting knife works in conjunction with the stacking pins. Through this solution it is thus possible to use bags when the sealing bar is heated with transverse welding in connection with an adjacent separating cut or simply to cut off sections of the film by switching off the heating. The solution according to the invention is therefore suitable for producing and stacking bags, but also suitable for producing and stacking foil blanks with a device, which in the end is simple, clear and maintenance-free.

In a further embodiment of the invention it is proposed that within the assembly carrying the knife and the stacking pins, the stacking pins are arranged parallel-displaceable relative to the knife. By this measure is it is possible by pulling away the stacking pins with only a slight increase in the distance the stacking device, the stack formed from bags or blanks from the Stacking device can be removed by simply dropping it down.

The stacking pins are in a further embodiment according to the invention withdrawn from the clamping device by a piston-cylinder arrangement, wherein particularly advantageously the piston of the piston-cylinder arrangement against the pressure a helical spring is movable. This measure ensures that the pressure to pull back the stacking pins only act on the piston on one side and spring pressure is available to put the stacking pins into operation.

In a further embodiment according to the invention, the stacking pins engage in recesses of an opposite pressure strip, which at the same time in one Area in the direction of movement of the film behind the stacking pins, the welding device for blocking the bag or the blanks. In further inventive Design, the upper edge of the pressure bar forms the counter blade of the knife, wherein the aforementioned pressure bar at the same time bar in a recess of a holding rests.

In a further embodiment of the invention it is proposed that the bar carrying the knife and a bar which is associated with the knife receiving bar, are provided with cooling channels through which water flows. This measure achieves that the heat that may emanate from the sealing bar does not affect the MEsser and the stacking pins transfers.

This causes disturbances in the stacking due to a heated knife and turned off heated stacking pins.

In a further embodiment of the invention it is proposed that two mutually movable sealing bars are present and around the one sealing bar around and in the space between this sealing bar and the tip of the knife receiving bar an adjustable band made of a heat-resistant plastic, in particular under the brand name "Teflon" is arranged and around the other Welding bar and in the space between this welding bar and the knife carrying the knife strip another adjustable, heat-resistant plastic tape under the brand name "Teflon" is arranged.

It has already been stated that the solution according to the invention allows To weld bags, but also by switching on the heating of the sealing bars only to separate these and also only to separate blanks. The inventive Construction by separating the welding device from the separating and stacking device by arranging them in different assemblies, which, however, become one with each other Movement unit are connected, makes it possible that in further inventive Design that receives the tip of the pins and at the same time the interlocking sweat band bearing pressure strip has a groove for receiving the cutting edge of the knife.

This solution is applied to a simplified device, which is only able to separate and stack blanks and at the same time with their stacking to be welded, provided a welding through welding bars for Formation of bags with a bottom is not provided and accordingly the welding device can be completely eliminated.

The invention is shown in the drawing using two exemplary embodiments explained in more detail. It is not limited to the forms of training presented, rather, further modifications within the scope of the invention are possible. It 1 shows a device according to the invention for welding and / or cutting in side view, partly in section, Fig. La one with the device A stack of bags produced according to FIG. 1, FIG. 1b shows a detail from FIG. 1 in an enlarged view, FIG. 2 the simplified device compared to FIG. 1 only for cutting and stacking, Fig. 2a one with the device according to Fig. 2 produced stack of blanks.

The thermoplastic plastic film 12, preferably in the form of a Hose, is through the two feed rollers 10 and 11 of the welding and cutting device as well as stacking device supplied. To produce transverse welds are available the two welding bars 13 and 14, which are in respective associated beams 15 and 16 are stored and are constantly moved towards and away from each other via this. Din Carriers 15 and 16 work together with helical springs, not shown in the drawing, which move the carrier with the sealing bars away from each other.

The movement towards each other is carried out by associated driven ones Cams 17 and 18 which engage rollers 19 and 20 attached to the carriers. The welding bars 13 and 14 each have associated glow rods 21 and 21a as well 22 and 22a for heating them.

A bar 23 is connected to the carrier 15 and to the carrier 16 is connected a bar 24. The bars 23 and 24 are with Iühlkanäle 25 and 25a or 26 and 26a provided, which have the task of one of the welding bars 13 and 14 outgoing heating to render harmless and such a thing The heating of the cutting knife 27 as a cold-acting knife is arranged in the bar 24. The stacking pins 28, in the drawing only one pin is shown in section, However, if there are several pins in a row, they are in a pin carrier strip 29 arranged. The holding bar 24 has a lower part 30 on which a Mounting flange 31, a cylinder 32 is arranged with a piston on whose Piston rod 33 is attached to the bar 29 driving the pins 28 via a flange 29a is.

Opposite the tips of the pins 28a is another ledge 34 is present, which has bores 35 for receiving the stacking pins 28. The bar 23 has a recess 36 above the pressure strip 34 for receiving the cutting edge of the knife 27. A welding pulse band 37 is also located on the pressure strip 34 for connecting the stacked bags or blanks with each other at their Stacking present in such a way that with the stacking of the bags or blanks each individual bag or blank fed to the stack with the previous one Bag or blank is connected by welding via the impulse belt.

The production and stacking of bags works as follows: The two feed rollers 10 and 11 have a fixed position. First of all are the welding bars 13 and 14 and the bars connected to this in terms of movement 23 and 24 are present in a position remote from one another. As soon as the feed the rotation of the feed rolls has ended, will the welding bars 13 and 14 and with these the bars 23 and 24 moved towards each other. This takes place via the heated welding bars through their welding surfaces 38 and 39 shows a transverse weld 40, shown in FIG. 1, which forms the bottom seam in bags represents. At the same time, the severing cut 41 is made via the cutting knife 27. The separating cut 41 is shown twice in Fig. La. It's the cut below the transverse seal 40 of the subsequent bag and at the same time the cut on the Filling opening of the previous bag.

When the bag is cut from the tube, it is placed on the pins 28 opened. It is understandable that the pouch should remain on the pins. the The method of operation described above is repeated as often as necessary, except for a corresponding one on the pins Number of bags have been opened. Simultaneously with the stacking of each As described above, bags are each followed by the welding pulse band 37 The bag is welded to the previously stacked bag. The welding is like this weak that it corresponds more to a liability. But it can also be used accordingly be strong. However, the welding pulse band expediently only brings such adhesion of the previous bag with the following that these: - # Adhesion of the previous The bag was later loosened by simply applying a hand-applied shear force will.

Having a certain predetermined number of bags on the pins has been hit, the piston in the cylinder 32 is moved by means of compressed air. This pulls the piston rod 33 and thus also over the flap 29a the pen holding strip # 29 in the indicated arrow direction 32 'to the right, so that When the pins are retracted, the stack of bags can fall down. pre-condition is that the pressure bar 34 is also slightly withdrawn so that the clamp is canceled.

It should be noted that the pressure strip 34 is displaceable within the strip 23 is, against the pressure of helical springs, not shown, to take into account the growing thickness of the bag stack.

The piston rod 33 and via this in connection with the bracket 29a the stacking pin strip 29 and the stacking pins 28 attached to it are at the creation and stacking of the bags in the indicated arrow direction 32 '' Helical springs 47 pushed forward. about these helical springs is also because the bar 29 to hold the stacking pins at the same time at most 24 is applied, the bar 24 with the knife 27 in the indicated arrow direction 32 '' in Slid towards the center of the device, increasing with the stacking Thickness of the bag stack the helical springs 47 are slightly compressed, in order to achieve the appropriate space and flexibility when stacking.

Fig. 2 shows the proviso that the welding bars 13 and 14 fell are because only blanks are made on the device shown in FIG which are shown in Fig. 2a. By eliminating the two sealing bars 13th and 14 as a result of the space thus gained, the cylinder 31 can be retracted the stacking pins 28 can be arranged in one plane with this. This results in a simplification. The bar 23 is also simplified according to FIG. 2. she has the Bores 35 mentioned in relation to FIG. 1 for receiving the stacking pins and also the recess 36 for receiving the cutting edge of the knife 27. The recess thus acts according to Art a shearbar. With 37 the welding pulse band is referred to, so that with the In the device shown in Fig. 2, the blanks also during their stacking be connected to one another by a slight weld 42.

The holes 43 are designated by the sharpened stacking pins 28 can be obtained in the blanks. These holes are very tiny holes that close again after pulling the stacking pins out of the stacking block.

Fig. 1 also shows that in each case around the welding bars 13 and 14 heat-resistant and adjustable straps 44 and 45 are drawn.

1 and 2 show that the welding device 13 and 14 of the stacking device 23, 24, 29 and with the cutting knife 27 and the stacking pins 28 represent separate assemblies according to FIG. 1 for common movement with one another are connected. By dividing it into separate assemblies, it is in maintaining of the drive by the cams 17 and 18 possible, the welding bars 13 and 14 also to expand and only the cutting and stacking device according to FIG. 2 to use if the foil layers are not welded, but only in sections should be separated and stacked as sections.

If, according to Fig. 1, the glow rods 21 and 22 in the associated welding bars 13 and 14 are configured, then no welding takes place either, so that the device according to FIG. 1 only makes a severing cut through the knife 27 exercises.

The device according to the invention is characterized by a simple one Basic structure with a quiet run with high work performance.

As the drawings show, the foils are particularly advantageous fed in the vertical plane and the bags stacked in the vertical plane. It is understandable that the device can also be provided to the films in feed in a horizontal plane and the bags and blanks obtained in a horizontal plane Stack level. With such an arrangement, the stacking pins become advantageous moved from top to bottom to release the block from the holder.

- Expectations -

Claims (9)

-Claims-1. Device for the production of bags or the like. Packaging made of thermoplastic plastic film and stacking the bags to form a block, with a separating and welding device consisting of two mutually movable welding bars for separating individual bags from a film tube, as well as with one in the direction of flow stacking device arranged immediately behind it, which is equipped with a device for Sealing of each newly attached bag with the previously stacked bag of the bag block is provided, the stacking of the bags by means of a counter-spring force movable bag clamping strip takes place and to transfer the individual bags into the Stacking position a movable pressure bar and the other parts of the stacking device including the welding device for welding each newly delivered bag with the stack of bags in their arrangement and function of the separating-welding device are independent and the bag clamping bar is provided with pins for stacking the bags is the one from the clamping surface of the bag clamping strip assigned to the pressure strip stand out, addition to patent application P 22 36 523.7-27, d a d u r c h g e k e n n z e i c h n e t that the welding device (12, 13) from the separating device in the form of a cutting knife (27) separate, but for common movement with one another connected assemblies and the cutting knife (27) and the stacking pins (28) in an assembly are available. 2. Apparatus according to claim 1, d a d u r c h g e k e n n -z e i c h n e t that within the the meter (27) and the Stacking pins (28) supporting assembly, the stacking pins (28) relative to the knife (27) parallel-displaceable are arranged. 3. Apparatus according to claim 2, d a d u r c h g e k e n n -z e i c h n e t that the stacking pins (28) can be displaced by a piston-cylinder arrangement (32) are. 4. Apparatus according to claim 3, d a d u r c h g e k e n n -z e i c h n e t that the piston of the piston-cylinder assembly against the pressure of a helical spring (40) is movable. 5. Device according to claims 1 to 4, d a d u r c h g e k e n n z e i h n e t that the stacking pins (28) in recesses (35) of an opposite one The pressure strip (34) engages, at the same time in an area in the direction of movement the film behind the stacking pins (28) the welding device (37) for blocking the bag carries. 6. Device according to claims 1 to 5, d a d u r c h g e k e It is noted that the upper edge of the pressure strip (34) is the counter blade of the knife (27) and the pressure strip (34) in a recess of a retaining strip (23) rests. 7. Device according to one or more of claims 1 to 6, d a it is indicated that the strip carrying the knife (27) (24) and the knife (27) receiving strip (23) with cooling channels through which water flows (25, 26) are provided. 8. Device according to one or more of claims 1 to 7, d a it is indicated that two welding bars that can be moved towards one another (13, 14) are present and around the one sealing bar (13) and in the space between the sealing bar (13) and the bar receiving the tip of the knife (27) (23) an adjustable heat-resistant band (44) and around the other sealing bar (14) and in a space between this welding bar (14) and the one carrying the knife (27) Bar (24) a further adjustable heat-resistant band (45) is arranged. 9. Device according to one or more of claims 1 to 8, d a it is noted that the receiving the tips of the pins (28) and at the same time carrying the welding device (37) for locking the bags Pressure list (34) has a groove (46) for receiving the cutting edge of the knife (27). L e r s e i t e