DE2922834A1 - Packing fluids, slurries, solids, in thermoplastic film hoses - using two ultrasonic welders forming vertical and horizontal seams - Google Patents

Abstract

The overlapping edges of a film of thermoplastic material formed into a tube are welded by the tool of an ultrasonic welder, which works directly with the filling tube of a packing machine. The machine packs materials ranging from fluids to powders and granulates, into a tube formed by turning a strip of film over a guide plate on to the outer surface of the tube, on which it is welded, filled and sealed by transverse seams spaced out at intervals. The transverse seams are produced by the tools of a second welding device which include the ultrasonic tool and a holding-up punch. These are both movable transversely to the line of motion of the tubular film and they have contact surfaces in the form of an "S" or a "Z". Used to provide a tubular bag machine for the packing of shampoos, fats, cheeses, sausage meat, slurries of explosives, and granular matter. The machine works at much higher speeds than those using glue, and welds thick films without a dangerous level of heat being generated. In addn. the vibration set up by the waves displaces particles which otherwise would remain in the seam.

Description

Device for packing liquids, slurries or solids by means of a tubular film The invention relates to a device for Packaging from liquids to powder or granular form Solids by means of a tubular film made of thermoplastic material, the is formed from a film strip through a forming shoulder to form a tube, the overlapping edges are welded together before the tubular film filled with the packaged goods by means of a filling tube and in sections through Cross locks is divided.

Devices of the type described above are as so-called Tubular bag machines known. They are used both for packaging shampoo, Fat, cheese and sausage masses and other viscous goods, such as slurry explosives, as also used for solids in powder or granular form. Usually strip-shaped film made of plastic is used in the known devices drawn over a form shoulder and thereby to a circular cross-section, deformed square or elliptical tube that surrounds a filling tube. The edges of the film strip deformed into a tube overlap and become continuously connected to one another by means of a longitudinal seam. This longitudinal seam is in the known method either produced by supplying glue or by direct welding of the edges using hot air or heated welding jaws in the form of plates or tapes As soon as the film tape turns into a closed tube has been generated, this is at its front end by means of a cross lock closed and filled with a certain amount of the product.

Then the filled hose section is at its rear opening closed by means of a second cross lock, so that the continuous The film tube produced encloses product quantities that are separated from one another in sections. The cross locks are made either by metallic clips or by cross seams gebil des, like the longitudinal seam, by adding glue or by a Welding process can be generated by means of hot air or heated welding jaws. the The tubular film divided by the cross closures is normally simultaneously or immediately after the cross-locking according to the position of the cross-locking divided into individual pieces.

Have the known devices of the type described above various disadvantages. On the one hand, the manufacturing speed is tubular Foil limited by the fact that for the production of the longitudinal seam on the overlapping The edges must have a certain amount of time before the glue has set or the welding process through sufficient cooling of the softened material is completed. On the other hand, films with a high melting point have to operate at high temperatures be welded. These temperatures are for dangerous or sensitive products not allowed at all. This makes the use of many otherwise desirable ones Packaging foils for these goods excluded.

Even if, for example, hot air with a suitable film is used for these goods the limited energy input limits the manufacturing speed.

The invention is based on the object described above To avoid disadvantages of the known prior art and a device of To create the type described above, with which almost all fillable products from liquids to solids in powder or granular form at high speed and without heating using a wide range of tubular Plastic films made of thermoplastic material can be packaged.

The solution to this problem by the invention is thereby characterized in that the overlapping edges of the film formed into a tube welded by means of an ultrasonic tool of an ultrasonic welding device that interacts directly with the filling pipe.

The inventive use of an ultrasonic welding device known per se, its Tool interacts directly with the jacket tube of the packaging device, becomes not only a limitation of the packaging due to the welding process speed, but also any heat effects on the packaged goods, because those introduced into the outer layer of the foil edge by the ultrasonic tool high-frequency mechanical vibrations directly in the film material frictional heat that softens the film material and is fixed with the one by the filling tube bottom layer welded together by flowing into one another.

After reaching the melting point, the generated in the film material ceases Friction on, so that a thermal overload and the emergence of an on the filling tube or heat sources radiating onto the packaged goods can be avoided.

Since the heat required to produce the longitudinal weld seam is thus generated only in the welding area, namely between the overlapping foil surfaces the temperature in the immediate area of the weld seam only rises a few degrees above the ambient temperature, so that even endangered or dangerous packaging goods be sunk into a tubular film with the device according to the invention can. It is also possible to use film materials - »ie, for example, polypropylene and polyester welding at high speed, which until now has been dangerous or sensitive goods can only be sealed with great effort and very slowly could. Another advantage of the device according to the invention results from this, that filler particles that accidentally get into the weld seam, ought to, through the high-frequency mechanical vibrations in the material to be welded be displaced from the weld seam area, so that even polluted Surfaces are flawlessly welded together, which is particularly important when using the inventive.

Apparatus on powdery solids is of great importance there diec powdery solids in the known devices to an incomplete Lead welding through dust. It should be noted that because of the different molecular structure of filling goods and packaging film the high-frequency mechanical vibrations of the ultrasonic welding device are measured in such a way In contrast to the packaging film, the contents can be affected by the vibrations is not heated.

This displacement of the product from the weld seam area is according to Another feature of the invention is exploited, even if the cross locks of the tubular film by means of a tool of a second ultrasonic welding device be produced, which as well as a counter holder transversely to the direction of movement tubular film is movably mounted.

This has the advantage of a considerable simplification compared to the previous cross locks, which were formed in particular by clips and not only required a complex locking device on the device, but also high costs for the clip material. Also was the packing speed limited by the attachment of the clips.

For example, there are explosives cartridges that are used in boreholes should not have any cross welding lying on a line, because these to protruding beyond the diameter of the cartridge closure parts on the Cartridge ends that make it difficult or difficult to insert the cartridge into the boreholes make even uncomfortable, it is proposed to develop the invention that Ultrasonic tool and the counter holder for making the cross locks with Form S- or Z-shaped end faces. Because of this training of the tool and the associated counter holder results in an S- or Z-shaped transverse seam, which for its entire length within the outline of the circular or elliptical Cross-section the cartridge is due to the shape of the tool and the counter holder according to the invention are thus the cross section of the cartridge protruding portions at the cartridge ends avoided.

In the drawing are an embodiment of the invention Device and two embodiments for the invention of the simple Cross-weld deviating cross-seam shown, namely: Fig. 1 shows a Front view of the device, FIG. 2 a perspective view of a part the filling pipe with the form shoulder and the sonotrode of the ultrasonic welding device, FIG. 3 shows a cross section according to the section line III-III in FIG. 2, FIG. 4 shows a perspective View of one end of a cartridge closed by means of an S-shaped transverse seam, FIG. 5 shows an end view of FIG. 4 and FIG. 6 shows an end view corresponding to FIG with a Z-shaped cross seam.

The illustrated in Fig. 1 front view of the device shows a box-shaped cladding 1, which in addition to the support frame, the drives and control devices for those units that exist in the illustrated embodiment the vertical front outer surface are arranged. It concerns here once to a provided with a funnel 2 filling tube 3, which in the upper area of a molded shoulder 4 is surrounded, which on an enlarged scale and in perspective is shown in Fig.2.

Over this form shoulder 4, a film tape 5 is drawn, which is from a Film roll 6 is drawn off via a deflection roller 7. This peeling occurs by means of two transport belts 8 'which are located in the middle area of the filling pipe 3 are arranged opposite one another. The conveyor belts 8 work with their run parallel to the longitudinal direction of the filling tube 3 on the Foil which has previously been formed into a tube by means of the forming shoulder 4.

As can be seen in FIG. 1, the conveyor belts 8 run at dai provided embodiment over three roles 9, of which at least a roller 9 is driven and another role to achieve the necessary Tension in the transport belt 8 is adjustable. The drive for the conveyor belts 8 is located inside c panel 1.

From the illustration according to FIG. 2 it can be seen that the overlapping Edges of the foil tape 5 by means of a tool 10 of an ultrasonic welding device 11 are welded. This ultrasonic tool known as a sonotrode or horn 10 interacts directly with the filling pipe 3, so that the tool 10 generated high-frequency mechanical vibrations directly into the film material are introduced and generate frictional heat there, which softens the film material. In this way, the material of the lower layer resting on the filling pipe 3 flows with the softened material of the upper layer of the film edge into one another, so that a continuous weld seam 12 results, which can be seen clearly in FIG.

Since after reaching the melting point, the Tool 10 generated friction ceases, both a thermal overload of the Foil material as well as the emergence of an on the filling tube 3 or on the packaged goods radiating heat source avoided. Especially when packing dangerous or sensitive goods there is thus the great advantage that the heating to seal the tubular film 5 is created only in the film 5.

This means that hazards or damage to the product are excluded closed. Since the heat required to produce the weld seam 12 is therefore only in the welding area, namely between the overlapping edges of the film thermoplastic film materials can be welded at high speed will.

Another advantage results from the fact that filling material particles, the to come; should get into the weld seam due to the high frequency mechanical vibrations in the material to be welded from the weld seam area be displaced. Even soiled surfaces are thus perfectly interconnected welded. This is particularly true when using those described above Device on powdery solids of great importance, as in the known methods the dust of such powdery solids a complete weld or Prevented sticking.

A second ultrasonic welding device 13 can be seen in FIG. its transversely to the direction of movement of the tubular film 5 movably mounted Tool 14 cooperates with an oppositely movably mounted counter holder 15. With this tool 14 and counter holder 15, which is below the lower end of the filling tube 3 are arranged, the cross closures 16 of the tubular film are produced, one of which a transverse lock 16 is indicated in FIG.

As by the mechanical merging of tool 14 and counterholder 15 that is filled into the tubular film 5 through the funnel 2 and the filling tube 3 A substantial part of the filling material is displaced from the area of the transverse seal 16 is and there in the manner described above, the high-frequency mechanical Vibrations of the tool 14 remove the remaining particles of the filling material from the weld seam area of the cross lock 16 can be displaced with the device described above a continuous filling process can be exercised without the risk there is that the cross closures 16 only an incomplete welding of the film material result.

To avoid that, in the case of a packaged item having a circular cross-section, for example a cartridge, locking parts protruding beyond the diameter at the ends of the packaged goods result, the tool 14 and the counter holder 15 with S- or Z-shaped end faces be designed so that there is an S- or Z-shaped cross seam, as shown in FIG FIGS. 4 to 6 are shown. This kind of Cross lock 16 avoids parts protruding beyond the diameter.

List of reference numerals: 1 casing 2 funnel 3 filling pipe 4 forming shoulder 5 Foil tape 6 Foil roll 7 Deflection roller 8 Transport belt 9 Roll 10 Tool 11 Ultrasonic welding device 12 Welding seam 13 Ultrasonic welding device 14 Tool 15 counter holder 16 cross lock

Claims (5)

Patent claims: Device for packaging liquids up to to solids present in powder or granular form by means of a tubular Foil made of thermoplastic material, which consists of a foil strip through a forming shoulder is gefor to a tube, the overlapping edges of which are welded together be before the tubular film by means of a filling tube with the packaged goods is filled and subdivided in sections by cross closures, characterized in that that the overlapping edges of the formed into a tube film (5) by means of a Tool (10) of an ultrasonic welding device (11) are welded directly cooperates with the filling pipe (3). 2. Apparatus according to claim 1, characterized in that the Cross closures (16) by means of a tool (14) of a second ultrasonic welding device (13) are produced, which as well as a counter holder (15) transversely to the direction of movement the tubular film (5) is movably mounted. 3. Device according to claims 1 and 2, characterized in that d the tool (14) and the counter holder (15) for producing the cross locks (16) are ausgebi det with S- or Z-shaped end faces. 4. Device according to claims 1 to 3, characterized in that that the tools (10,14) of the ultrasonic welding devices (11,13) in front of an outer surface the box-shaped lined packaging device are arranged. 5. Device according to at least one of claims 1 to 4, characterized characterized that especially when packing dangerous or sensitive Goods the heating for sealing occurs only in the film (5) and the filling material is displaced from the welding area without risk of damage.