DE8813378U1 - Filter bags, especially infusion bags for beverages such as tea or similar. - Google Patents

Description

Filter bags, especially infusion bags for beverages
like tea or the like

The innovation relates to a filter bag, in particular an infusion bag for drinks such as tea or the like according to the preamble of claim 1.

Infusion bags have become known, for example for tea, which are made from a rectangular cut of paper fleece, which are sealed along the free longitudinal edges. A holding thread is fixed by sealing in the upper edge, with which the bag can be lowered into a liquid. It is also known to first form an elongated tube from a cut, e.g. with tea leaves, finer or

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Patent Attorneys: European Patent Attorneys - Authorized Representatives before the European Patent Office Attorney admitted to the Hamburg courts

Deutsche Bank AG Hamburg. No. 0928497 JBbZ EOO «TO 0OJ Postal check Hamburg 28 42-206
Dresdner«fank^G Hamburg. Nrj 9?3 6QS^fBLZ 200 800 00)

larger tea leaves or herbal tea (leaves, flowers, fruits) and fold the ends of the tube against each other and fasten them together with a staple. The holding thread is attached with the help of a staple. Such tea bags are normally produced as portion packs, the filling quantity of which is sufficient for one cup, for example. The user has no possibility of varying the amount of tea. Furthermore, only common types of tea are offered in such tea bags.

An infusion bag for tea has become known from EP-A-0 212 561, which can be filled by the user with a desired type of tea in the desired quantity via an upper opening. Of course, such an infusion bag is also suitable for holding other substances, such as spices, rice and the like. In the known bag, a rectangular blank is made of liquid-permeable, sealable paper fleece, which is folded over along one side of the blank to form an edge section to form a seam into which a holding thread is inserted. The blank is then placed around a scoring line perpendicular to the sealed edge area and sealed at the two free edges. The ends of the holding thread are led out at one end of the seam and can be labeled with a suitable label.

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get connected.

The known construction is satisfactory for the desired application purposes. In particular, the thread guide enables the bag to be closed sufficiently at the top. However, the manufacturing process for producing the known bag requires a relatively large amount of effort. In the known bag, the holding thread is inserted before the first section is folded over. It therefore takes part in the subsequent manufacturing steps. However, the mechanical handling of a partially finished blank with the holding thread is relatively difficult.

When the bag is pulled together at the top edge using the holding thread, the main load occurs where the thread reverses its direction. Since the fleece paper is relatively thin and tears easily, care must be taken to ensure that the surface load occurring at this point is not too great. A relatively thick thread must therefore be used in order to keep the surface pressure low. However, it can happen that the paper tears at the point most subject to stress , which means that it is no longer possible to pull it together properly.

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When brewed in a tea bag, tea forms a kind of sponge with a larger volume than its original volume. With the usual tea bags, the tea has no opportunity to expand sufficiently, so that a relatively compact sponge is created, which prevents sufficient water from reaching all the tea leaves for complete extraction.

The innovation is based on the task of improving a filter bag of the type mentioned above so that it is particularly easy to manufacture and can be easily closed with the drawstring after filling without tearing.

This object is achieved in accordance with the invention by the features of the characterizing part of claim 1.

In the new filter bag, the rectangular cut is folded by a bottom width to cover the wall sections. Then only the two free sides of the turning sections are sealed, while a seam is formed on the upper sides of each turning section by sewing in an upper turning section and sealing it with the turning section. It is also important that two side cuts are taken, which

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be inserted between the seam sections and the corresponding wall sections before the Saura sections are sealed. The two thread sections are preferably knotted together at at least one end.

The innovative design of the filter bag has significant advantages in terms of manufacturing technology. The cut can be pre-folded in the production machine without any difficulty by folding the seam sections over and placing the wall sections against each other around the bottom fold. Sealing can then take place in a single operation. Shortly before sealing, the thread sections are inserted. They can be held at both ends in the sealing station. After sealing, the innovative filter bag is largely finished and all that is required is to knot the thread ends at at least one end. This does not cause any difficulties, however, as knotting devices are known per se.

The knot naturally increases the contact surface on the deflection edge in the seam when pulling the holding thread section at the other end. This means that the paper is subjected to less stress than with a smooth thread. With the same surface load, a thinner

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Thread can be selected. Alternatively, however, the free thread ends can be connected in another way, e.g. by welding, a pressing element made of plastic or metal, by welding in a plastic element or the like.

In one embodiment of the innovation, the side winds are not sealed in the area of the seam. This makes it easier to fill the bag according to the innovation and also easier to tighten when pulling on the holding thread.

According to a further embodiment of the innovation, the width of the edge section folded over to form the hem is a multiple of the thread thickness. According to a further embodiment of the invention, the width of the sealing seam is only a part of the width of the edge section. Finally, according to another embodiment of the innovation, the width of the space taken up by the thread is a multiple of the thickness of the thread. These features help to make it easier to unfold the hem area when the holding thread is pulled. This prevents the hem from being partially opened or the material in the hem area from being torn.

So that, for example, when brewing tea, the volume increase

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of the tea, one design of the innovation provides that the bag is formed by two base sections hinged to the respective wall sections, which are hinged to one another via a fold line and the inwardly folded base sections are connected to the wall sections and to one another by heat sealing in an extension of the sealing seam of the side walls. This allows the bag to move out in the lower area perpendicular to the plane of the wall surfaces and form a sufficient storage volume. Sealing beyond the base sections has the advantage that when the bag is expanded, no outward-protruding corners are formed that could interfere with removing the bag from the liquid, for example from a teapot or the like.

A label is preferably attached to one side of the thread ends. The label can consist of sections glued together, between which the thread ends are guided. The label sections are preferably formed from a cut piece and connected to one another via a groove line. To prevent the thread ends from slipping out of the label, the free ends protruding beyond the label are also knotted according to one embodiment of the invention.

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It is understood that the new bag is particularly suitable for the preparation of tea, but is not limited to this. It can be used for all products in which active ingredients are extracted using water or another liquid or which are made by water and

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for example, cooked, such as rice.

The innovation is explained in more detail below using drawings.

Fig. 1 shows a plan view of a blank for the bag according to the invention.

Fig. 2 shows in perspective a bag partially erected from the blank according to Fig. 1.

Fig. 3 shows the top view of the flat bag after final assembly.

Fig. 4 shows an enlarged perspective view of an adhesive label shortly before application.

Before going into the details shown in the drawings, it should be noted that each

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the features described may be of essential innovation in themselves or in conjunction with features of the claims.

Fig. 1 shows a blank 10 made of sealable filter fleece paper. The rectangular blank has a central crease line 11, to which crease lines 12, 13 run parallel and at a distance. The crease lines 11 to 13 form base sections 14, 15. Wall sections 16, 17 are hinged to the base sections via the crease lines 12 and 13, respectively, and hem sections 20, 21 are hinged to the wall sections 16, 17 via crease lines 18, 19.

During assembly, the base sections 14, 15 are folded up in a roof shape, as can be seen in Fig. 2. At the same time, the wall sections 16, 17 are folded against each other around the crease lines 12, 13. In addition, the hem sections 20, 21 are folded inwards around the crease lines 18, 19. By placing the sections shown in Fig. 2 on top of each other, they can then be connected to each other by heat sealing. Before folding over the hem sections 20, 21 or before sealing, two thread sections 22, 23 are inserted (see Fig. 2).

In Fig. 3 the individual sealing seams can be seen.

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Sealed seams 24, 25 connect the wall sections 16, 17 to one another at the free edges. In the base area, the base sections 14, 15 are also connected to one another and to the wall sections 16, 17 by heat sealing in extension of the seams 24, 25. Sealed seams also connect the hem sections 20, 21 to the wall sections 16, 17, one of which is shown at 26. As can be seen, the sealed seams 24, 25 end before the hem formed by the hem sections 20, 21.

The thread sections 22, 23 are knotted at both ends, as shown at 27 and 28. An adhesive label 30 is glued to the thread sections 22, 23 at one end. As can be seen from Fig. 4, it consists of two sections 31, 32, which are part of a one-piece cut and can be folded against each other via sins nillinis 33. The label sections 31, 32 are glued to each other. The knot 28 prevents the holding thread sections 22, 23 from being pulled out of the label 30.

The unfolding of the blank 10, the insertion of the thread sections 22, 23 and the subsequent sealing of the
Sections are made in a suitable production machine
completely automatically. The product produced in this way

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and bags made of filter fleece paper shown in Fig. 3
is manufactured and packaged flat.

By grasping the upper edge areas of the seam, the bag can be opened and filled with a substance, for example tea. Then, by grasping the seam and the thread sections 22, 23, the upper seam is tied together so that the bag is largely closed. An increase in the volume of the substance filled in can be taken into account by bulging the side walls 16, 17. The base sections 14, 15 are partially unfolded so that a considerable increase in volume is achieved.

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Claims (7)

- 12 claims : 1. Filter bag, in particular infusion bag for drinks such as tea or the like, in which a flat blank made of sealable filter fleece paper is formed at the edges by folding and sealing to form a bag that is open at the top, in which a seam is also formed by folding the upper edges and sealing the folded edge sections, into which a holding thread is inserted, which is led out at one end of the seam with two thread ends, characterized in that the wall sections (16, 17) come to lie against one another by folding the blank around a bottom fold (11, 12, 13), only the two side edges of the wall sections (16, 17) are sealed, a separate seam is formed on the upper edge of each side wall (16, 17), into which a thread section (22, 23) is inserted, which protrudes from the seam at both ends and the thread ends of the thread sections have a connection at at least one end, preferably are knotted (27, 28). 2. Filter bag according to claim 1, characterized in that the side walls (16, 17) are unsealed in the region of the seam, .../13 ·« «· · * t ti it &igr; · »> » I - 13 - 3. Filter bag according to claim 1 or 2, characterized in that the width of the upper edge sections (20, 21) folded over to form the seam is a multiple of the thread thickness. 4. Filter bag according to claim 3, characterized in that the width of the sealing seam (26) is only a part of the width of the edge portion (20, 21). 5. Filter bag according to claim 3 or 4, characterized in that the width of the space accommodating the thread (22, 23) in the seam is a multiple of the thickness of the thread. 6. Filter bag according to one of claims 1 to 5, characterized in that the bottom is formed by two bottom sections (14, 15) hinged to the respective wall sections (16, 17), which are hinged to the respective wall sections (16, 17) via a fold line (12, 13) and the inwardly folded bottom sections (14, 15) are connected by heat sealing to the wall sections (16, 17) and to one another in an extension of the sealing seam (24, 25) of the side walls. 7. Filter bag according to one of claims 1 to 6, .../14 Il ·· I t<M Ittl IHt 11 !&bull;&bull;&bull;II * · *· characterized by a label (30) connected to the thread ends (22, 23) on one side of the seam, which consists of two label sections (31, 32) glued together, between which the thread ends come to lie. Filter bag according to claim 7, characterized in that the label sections (31, 32) are hinged to one another on one side.