EP1142789B1 - Method and device for making more compartments infusion bags - Google Patents

Description

The invention relates to a method for producing multi-chamber infusion bags for a substance to be leached out by an infusion liquid, in particular tea, from filter material, from the bag-like chambers with at least a substance quantum of the substance to be leached is formed, which are attached at one end to a handle, with two chambers on each side of a flat Handle can be placed directly opposite.

Tea bags and especially double chamber tea bags and methods for their Manufacturing is known from practice in various process variants. From GB-A-681 816, for example, a double chamber bag is known from a W-shaped fold in a tubular piece of filter material is formed transversely to its length. As a result of this fold, the two open ends of this piece of hose brought together and can then be filled with a tea portion. The open ends are then in the Usually folded and closed by being stapled, knurled or sealed by heat sealing. Also along the one that closes the tube piece The tea bags are longitudinally seamed by knurling or heat sealing locked. Knurling in particular is not for teabag making machines suitable that work at high speed because at high throughput speeds the fibers of the filter material have no time to form a firm grip. When in use Heat sealing is the speed determining step in heating the Sealing point.

A method and an apparatus for producing double-chamber infusion bags is also known for example from EP-B1-0 448 325. With this known processes, the double-chamber bags are produced by that two endless webs of finished single-chamber bags are brought together side by side and are connected to one another in their head regions by heat sealing. Following this connection, the individual double-chamber infusion bags severed from the endless web.

Based on this prior art, the object of the invention to create a process for the production of infusion bags, which A secure connection even with machines with high throughput speeds of the filter material guaranteed. The invention is also based on the object a device for the production of multi-chamber infusion bags according to this Creating procedures.

The procedural solution to this problem is according to the invention characterized in that the two chambers above their head end with the handle by laser welding get connected.

By using a laser it is due to the high energy density of the Laser beam possible for the first time to create a connection process that the Throughput speed of modern infusion bag production and filling machines not belittled.

The chambers used in the method according to the invention can be closed or be open on one side. According to the invention, by laser welding the bag-like chambers are closed at the head end become.

According to a further feature of the invention, that generated by the laser Light energy focused on the welding area and converted into heat that the weldable contained in the filter material of the chambers and / or in the handle Material heated and welded under pressure. So it's up simple meadow possible to reliably connect the chambers with the handle and if necessary also to close.

So that the conversion of light energy into heat takes place quickly and reliably, According to the invention, printing marks can be arranged on the handle absorb the light energy. It is also possible to have a apply a weldable coating to the handle if it does not run out weldable material. The handle is preferably called continuous continuous belt between the chambers.

The device for producing multi-chamber infusion bags has Transport means for feeding the chambers to be connected to one another Joining station. According to the invention, these means of transport are two counter-rotating transport and pressure rollers trained over the individual chambers can be fed to the joining station one after the other. To the area the joining station, the light beam of at least one laser can be focused via the the chambers can be welded to the handle at the head end and, if necessary, additionally are lockable.

By feeding individual chambers to the joining station Device according to the invention can be used particularly flexibly, since different Chambers containing substance quanta can be connected to one another, whereas in the device known from the prior art the supplied chambers form an interconnected endless path.

According to a practical embodiment of the invention it is proposed that the opposing transport and pressure rollers on their respective Have peripheral surfaces pockets for receiving a chamber, respectively the head ends of each chamber on a raised bridge between the pockets is stored, and that the opposite rotational movement of the Transport and printing rollers is synchronized so that there are two Intermediate webs at the area forming the joining station with the smallest Distance directly opposite each other. The distance is advantageously the two paired transport and pressure rollers to each other so dimensioned that the intermediate webs opposite each other at the joining station the head ends of two chambers to be welded together press. This ensures that an intimate and lasting The parts are connected to each other.

For welding the parts to be joined together, the at least one is Laser arranged so that its laser beam can be focused on the joining station.

In an alternative embodiment, two lasers are in the area of the joining station arranged that the laser beams from both sides of the supplied Handle can be focused on the joining station. The use of two lasers for welding from both sides is particularly advantageous to a uniform and rapid heating and melting of the welding area to achieve.

According to a practical embodiment of the invention, the Intermediate webs on through holes extending radially through which the Laser beam of the laser arranged inside the transport and printing roller is focusable on the joining station. This configuration ensures that the laser beam is always aimed directly at the joining station.

According to a first embodiment of this embodiment, each transport and Printing roller arranged a laser fixed to the joining station. As soon as two intermediate webs face each other at the joining station, the Laser beams of the two lasers on the ones stored on the intermediate webs Head ends of the chambers directed to weld them to the handle.

According to a second embodiment, there are transport and printing rollers in each several lasers rotating with the respective transport and printing rollers arranged that each intermediate web is assigned a laser.

Finally, the invention proposes that CO ₂ lasers or diode lasers be used as lasers. The diode lasers are characterized by the fact that they can be focused particularly precisely. The preferred wavelength range for the diode lasers is 10 µm.

Fig. 1

eine schematische Seitenansicht einer ersten Ausführungsform einer erfindungsgemäßen Vorrichtung;

Fig. 2

eine schematische Seitenansicht einer zweiten Ausführungsform einer erfindungsgemäßen Vorrichtung;

Fig. 3

eine vergrößerte schematische Detailansicht des Ausschnitts III gemäß Fig. 2;

Fig. 4

eine schematische Seitenansicht einer dritten Ausführungsform einer erfindungsgemäßen Vorrichtung und

Fig. 5

eine vergrößerte schematische Detailansicht des Ausschnitts V gemäß Fig. 4.

Further features and advantages of the invention emerge from the following description of the associated drawing, in which three exemplary embodiments of a device according to the invention for producing multi-chamber infusion bags are shown schematically by way of example. The drawing shows:

Fig. 1

a schematic side view of a first embodiment of a device according to the invention;

Fig. 2

a schematic side view of a second embodiment of a device according to the invention;

Fig. 3

an enlarged schematic detailed view of section III of FIG. 2;

Fig. 4

is a schematic side view of a third embodiment of a device according to the invention and

Fig. 5

3 shows an enlarged schematic detailed view of section V according to FIG. 4.

Fig. 1 shows a schematic side view of the structure of a device for Manufacture of multi-chamber infusion bags. The device consists in essentially of two arranged in pairs and against each other running transport and pressure rollers 1, which are arranged so that each other a joining station 2 at the point of the smallest radial distance from one another form to connect individual chambers 3.

As can be seen from the figures, the peripheral surface of each transport and Print roller 1 on individual pockets 4, each for receiving one Serve chamber 3. The individual pockets 4 are formed by increased Intermediate webs 5 separated from each other. As in particular the illustrations in FIG. 3 and 5 can be seen, the individual chambers 3 are so on the Transportund Pressure rollers 1 stored that the substance to be leached containing bag part in the pocket 4 between two intermediate webs 5, while a head end 6 of each chamber 3 on the front in the transport direction Intermediate web 5 rests.

In addition to the supply of the chambers 3 to be connected to each other, in the Illustrated embodiment of an apparatus for producing Multi-chamber infusion bags of the joining station 2 simultaneously with the chambers 3 also supplied a handle 7, which is designed as a band-shaped carrier material is.

To connect the individual chambers 3 with each other and also with the Handle 7 is arranged in the area of the joining station 2 at least one laser 8, through which the parts to be connected are welded together.

In the first embodiment shown in FIG. 1, a laser 8 is arranged above the joining station 2 on both sides of the handle 7 fed as an endless belt in such a way that the respective laser beams are precisely focused on the joining station 2. A CO ₂ laser is particularly suitable for this purpose.

In the second embodiment shown in Figures 2 and 3 a laser 8 is arranged in the interior of each transport and printing roller 1, whose respective laser beams are precisely focused on the joining station 2. The Intermediate webs 5 have radially extending through bores 9, through which the laser beams are focused on the joining station 2.

The third embodiment shown in FIGS. 4 and 5 differs from that second as shown in FIGS. 2 and 3 in that each transport and Printing roller 1 several with the respective transport and printing roller 1 rotating Lasers 8 are arranged such that each intermediate web 5 has a laser 8 assigned.

As a laser 8 for the arrangement inside the transport and printing rollers 1 diode lasers are particularly suitable, preferably with a wavelength of 10 µm.

The devices for production shown in Figures 1 to 5 Multi-chamber infusion bags work as follows:

The paired transport and pressure rollers 1, which according to the Arrows 10 rotate in opposite directions, individual chambers 3 become so abandoned that each chamber 3 in a predetermined, in the peripheral surface of the respective transport and pressure roller 1 trained pocket 4 comes to rest. The head ends 6 of the chambers 3 are each on the in the transport direction the transport and pressure roller 1 front intermediate web 5 stored ..

The rotation of the two transport and pressure rollers 1 is synchronized so that two intermediate webs 5 each on the area forming the joining station 2 the smallest distance directly opposite each other, like this in particular 3 and 5 can be seen.

In the illustrated embodiment, the joining station 2 is simultaneously with the Chambers 3 also supplied the handle 7, which in this case as a band-shaped Carrier material is formed, which via an endless belt of the joining station 2 is fed.

3 and 5, the distance between two Intermediate webs 5 in the area of the joining station 2 dimensioned so that the parts to be connected to one another, namely the two head ends 6 of the chambers 3 and the intermediate handle 7 are pressed against each other.

The actual connection of the parts with each other takes place via the laser 8 The embodiments shown in FIGS. 2 to 5 are the lasers 8 arranged inside the transport and printing rollers 1. The laser beams can be made through through holes 9 formed in the intermediate webs 5 Focus exactly on the joining station 2.

The handle 7 is closed on both sides at the head ends 6 of the chambers 3 welded point with print marks 7a, which the impinging Absorb light energy and convert it into heat. This heat becomes Welding the handle 7 with the chambers 3 used. As welding material are in the material of the chambers 3 at least in the area of Head ends 6 existing plastic and / or one on both sides in the area Print marks 7a made on the handle 7 coating weldable plastic used.

By the laser beams hitting the parts to be connected these parts are heated to the melting temperature, so that there is a permanent cohesive connection results. By pressing the parts together on the Joining station 2 can also achieve this cohesion if the Parts can only be melted. To be particularly good for laser welding to be suitable, the filter paper forming the filter material has at least in the Area of the head ends 6 plastic fibers by the laser beams be melted. Likewise, the handle 7 at least in Connection area, preferably a coating of one on both sides weldable plastic material, especially polyethylene, so that too a fusion weld connection can be made here.

In the illustrated embodiments, in which the handles 7 in shape An endless belt are fed, also form the finished multi-chamber bags an endless belt. Of course, it is also possible feed individual handles 7 or the finished multi-chamber bags in the area to separate the joining station 2.

The use of the laser 8 has the advantage that even at high Cycle speeds of the machine a safe and permanent connection of the individual chambers 3 with the handle 7 to multi-chamber infusion bags is possible.

LIST OF REFERENCE NUMBERS

1

Transport and printing roller

2

joining station

3

chamber

4

bag

5

gutter

6

head

7

handle

7a

print mark

8th

laser

9

Through Hole

10

arrow

Claims (15)

1. Method for making multi-compartment infusion bags for a substance, in particular tea, which is to be extracted by an infusion liquid, from a filter material, from which bag-like compartments (3) with at least one substance quantity of the substance to be extracted are formed, which bags are fastened by one end to a handle (7), wherein two compartments (3) are laid directly opposite one another against one side of a flat handle (7),
   characterised in that the two compartments (3) are welded to the handle (7) by laser welding by way of their top end (6).
2. Method according to Claim 1, characterised in that the bag-like compartments (3) are at the same time closed at their top end (6) by laser welding.
3. Method according to Claim 1 or 2, characterised in that the light energy which is generated by the laser (8) is focused on the weld region and converted into heat, which heats the weldable material which is contained in the filter material of the compartments (3) and/or handle (7) and welds it under pressure.
4. Method according to Claim 3, characterised in that colour markings (7a), which absorb the light energy, are disposed on the handle (7) in order to convert the light energy into heat.
5. Method according to Claims 3 and 4, characterised in that a weldable coating is applied to the handle (7) in the weld region.
6. Method according to at least one of Claims 1 to 5, characterised in that the handle (7) is guided as a coherent continuous tape between the compartments (3).
7. Device for carrying out the method according to at least one of Claims 1 to 6, with transport means for feeding the compartments (3) which are to be connected together to a joining station (2),
   characterised in that the transport means are formed as two pressure rollers (1) which run towards one another and by way of which the individual compartments (3) can be fed in succession to the joining station (2), and the handle (7) can be fed at the same time as the compartments (3), and that the light beam at least of one laser (8) can be focused on the region of the joining station (2), by way of which the individual compartments (3) can be welded to the handle (7) at the top end (6) and optionally closed in addition.
8. Device according to Claim 7, characterised in that the transport and pressure rollers (1) running towards one another comprise pockets (4) at their respective circumferential surfaces to accommodate a compartment (3), wherein the top ends (6) of each compartment (3) can be supported on a raised intermediate web (5) between the pockets (4), and that the opposite rotational movement of the transport and pressure rollers (1) is synchronised such that two intermediate webs (5) in each case lie directly opposite one another at a minimum spacing in the region forming the joining station (2), and the compartments and the handle can be welded together under pressure.
9. Device according to at least one of Claims 7 and 8, characterised in that the at least one laser (8) is disposed such that its laser beam can be focused on the joining station (2).
10. Device according to at least one of Claims 7 and 8, characterised in that two lasers (8) are disposed in the region of the joining station (2), the laser beams of which lasers can be focused from both sides of the joining station (2).
11. Device according to at least one of Claims 8 to 10, characterised in that the intermediate webs (5) comprise radially extending through-bores (9), through which the laser beam at least of one laser (8), disposed inside the transport and pressure rollers (1), can be focused on the joining station (2).
12. Device according to Claim 11, characterised in that a laser beam (8) is aimed in a stationary fashion at the joining station (2) in each transport and pressure roller (1).
13. Device according to Claim 11, characterised in that a plurality of lasers (8), rotating with the respective transport and pressure roller (1), are disposed in each transport and pressure roller (1) such that a respective laser (8) is associated with each intermediate web (5).
14. Device according to Claim 13, characterised in that the lasers (8) which are used are diode lasers.
15. Device according to at least one of Claims 7 to 11, characterised in that the at least one laser (8) is a C02 laser.

Images