Method for attaching a tag to a tea bag

Abstract: The method for attaching a tag (1) to a tea bag (2), where the bag (2) and the tag (1) both have at least one border (5) with reduced thickness, comprises the following stages: hooking of a first end or leader (31) of the said thread (3) by an eye (41) of a needle (4) and running of the thread (3) into the said border (5) through to the opposite side of the border itself by a value (L4) sufficient to make a loop (30) in the thread (3); widening of the said loop (30) in such a way as to form an aperture (32) through which the said thread (3) can be inserted; insertion of the said leader (31) into the aperture (32) in the loop (30) and releasing of the said thread (3) by the needle (4), the thread (3) being pulled in such a way as to tighten the resulting knot (33).

Description: The present invention relates to a method for attaching a tag to a tea bag, in particular for attaching a tag to a filter-bag containing tea, chamomile, and similar products, using a thread fixed to the bag at one end and to the tag at the other to form a convenient means of holding the bag itself both during and after infusion. In the present description, reference will be made to bilobate tea bags but without thereby restricting the application of the disclosure to other kinds of tea bags. Bilobate tea bags, which are the most common type of single-dose tea bags, are formed of a sheet of filter paper from a continuous roll, folded and sealed longitudinally to form a tube; while the tube is being formed, charges of product are deposited on the filter paper at regular intervals in longitudinal direction; each section of tube is then folded into a W shape at the centre, between two consecutive charges, so as to form the so-called lobes of the bag, each containing a charge of product. Finally, the two lobes are pressed against one another, their open ends are sealed and, at the same time, a thread connecting them to a tag is attached to them at the sealed end. The tea bag made in this way can be picked up and handled by the thread, especially after it has been placed in boiling water, since one end of the thread is fixed to the bag and the other end to a tag which can be conveniently held between the fingers. The sealing of the bag and the attachment of the thread can be effected in different ways. In US patent 2.307.998, which discloses a type of tea bag and the method for making it, the method which envisages knots to fix the thread to the bag and to the tag is attributed to prior art; in one of the examples in the drawings and in the description, the thread is secured to the tag and to the bag by a staple with the thread knotted to it, in another example, by a knot only. According to the said patent, knotting does not lend itself to high speed production; indeed, present-day industry has adopted stapling as the fastest and most effective way of securing tags to tea bags. The disadvantage of this method, however, especially to secure the tag thread to the bag, is that the metal which the staples are made of may contaminate the infusion creating a disagreeable taste and even health problems. Another method of securing the thread is described in US patent 4.415.597, which discloses a filter-bag made of filter paper coated with a heat sealable layer of thermoplastic material, with a tag secured by a thread held at one end between two heat sealed edges of the bag, wound around the bag and detachably heat sealed to the outside of the bag itself at several points. Hence, the bag, or at least part of it, is made of paper and thermoplastic material. This type of material has disadvantages similar to those mentioned above, since contact between the thermoplastic material and the infusion livid at high temperatures can lead to contamination of the brew by substances in the thermoplastic material. Another disadvantage of the bag disclosed by this patent is the cost of the thermoplastic material, which is considerably higher than ordinary filter paper. Furthermore, in WO-95/32905 it is disclosed a method for closing filter bag for infusible products and for connecting a tagged thread thereto. The filter bag is closed by folding a flap made in the upper part of the filter bag. A thread is attached thereto directly by a terminal portion of the thread or indirectly by auxiliary threads. In particular, it is disclosed that a needle translates in a first direction and passes through the material, thus making therein a hole. When the needle goes up, a loop is formed in the part of the thread connected with the needle and it is hooked by a looper rotating in a determined direction. Also this known method is not particularly adapted for the above-mentioned high speed production. The object of the present invention is to eliminate the disadvantages mentioned above. The invention, as characterized in the claims, achieves this object by providing a method for securing a thread to a tea bag and to a tag by means only of knots and without using either metal staples or heat sealing processes. The characteristics of the invention are laid out in the claims below and the advantages of the disclosure are apparent from the detailed description which follows, with reference to the accompanying drawings, which illustrate preferred embodiments of the invention by way of example and in which: Figures 1, 2, 3, 4, 5 and 6 are schematic side views, with some parts cut away, showing a consecutive series of steps in a process embodying the method disclosed herein; Figure 7 is a top, perspective view of a tea bag made in accordance with the present invention; Figures 8, 9, 10, 11 and 12 are schematic side views, with some parts cut away, showing details of the possible parts and stages of the embodiment illustrated in the previous figures; Figures 13, 14, 15, 16, 17 and 18 are schematic views, with some parts cut away, showing a consecutive series of steps in another process embodying the method disclosed herein; Figures 19, 20, 21, 22 and 23 are schematic views, with some parts cut away, showing a consecutive series of steps in yet another embodiment of the present invention. The method disclosed by the present invention will now be described with reference to the drawings listed above, which are not all in the same scale, in order to better illustrate details of the invention. The method enables a tag 1 to be attached to a tea bag 2 using a length of thread 3 fixed to the tea bag at one end and to the tag 1 at the other. The tea bag 2 and the tag 1 have at least one border 5 with reduced thickness to enable the thread 3 to be fixed to it. The thread 3 may be attached to the tag 1 at the same time as it is attached to bag 2 or the two operations may be carried out in different stages, depending on the equipment used. As shown especially in Figs. 1 to 6 and 8 to 12, the method may include the stages described below. The first stage (which may in some cases be unnecessary) consists in cutting the thread 3 to a length equal to the desired distance between tag and bag plus the length required to make at least two knots, the resulting length of thread 3 being positioned in such a manner that at least a section of it is opposite (parallel in the drawings) to the border 5 where it is to be fixed. During the next stage, which is the first if the thread does not need to be cut, a first end or leader 31 of the thread 3 is hooked by the eye 41 of a needle 4. The eye may be of the open type, as illustrated in detail in Fig. 8. The needle is then run into the border 5 in a first direction R through to the opposite side of the border itself by a value L4 sufficient to make a loop 30 in the thread 3, that is, to form a section where the thread is doubled up, as shown in Fig. 2. Next, only the needle 4 is partially withdrawn through the border 5 and twisted about its axis X in direction F through at least 180 degrees, leaving the doubled length of thread longer than the part of the needle that still protrudes so as to widen the loop 30 to form an aperture 32. In Fig. 3, the broken line shows the position of the needle 4 after its initial movement and D4 shows the position after the needle is partially withdrawn. The rotational motion F of the needle 4 through at least 180 degrees twists the loop partially onto itself, allowing it to assume a configuration suitable for tying a knot. The leader 31 is then inserted into the aperture 32 defined by the loop 30 and the needle 4 is pulled out to release the thread 3, the latter being subjected to a pulling action which tightens the resulting knot 33, as shown in Figs.4, 11 and 12. In practice, when the thread 3 is pulled, the loop 30 passes almost entirely through the border 5 to the side from which the pulling action is exerted, while the leader 31 and a section of the thread 3 remain on the other side, the section of thread passing under, and tying, the border 5. Once the knot 33 has been tightened, two further stages illustrated in Figs. 5 and 6 are possible to obtain an end product similar to that shown in Fig. 7. In these two final stages (Figs. 5 and 6), the section of the thread 3 between the tag 1 and the bag 2 is gathered up into a coil 35, for example by curling. The tea bag 2 and the tag 1 are then pressed together, with the coil 35 of thread 3 between them. The tag 1 may be made of paper coated with low temperature thermal adhesive and attached to the bag 2 by heat sealing at only two points 11, that is to say, in two areas of very limited extent. The partial heat sealing of the tag 1 to the bag 2 forms a detachable seal between the tag 1, the coil 35 and the bag 2 so that the tag 1 can be easily pulled free of the bag 2, while the adhesive 11 remains on the tag 1. During infusion, therefore, the adhesive does not come into contact with the boiling hot water used to make the brew. As shown in Figs. 13 to 18 (which, for convenience, illustrate only the attachment to the tag 1) the thread may be manipulated with a crochet needle, similar in many respects to a common crochet hook. In this case, the stages embodying the method disclosed differ from those described above in the following aspects. Initially, the part of the thread 3 to be hooked by the eye 41 of a crochet needle 4 is on the opposite side of the tag 1, as can be seen in Fig. 14. The needle 4 is then run through the border, hooks the thread 3 and pulls it back in a first direction R through the said border in a manner similar to that envisaged by the first embodiment, described above, and as illustrated in Figs. 15, 16, and 17. In Fig. 18, the needle 4 is moved back partially in a direction R' opposite to the first direction R and then twisted about its axis X through at least 180 degrees, leaving a doubled up section of thread on the other side, longer than the part of the needle that still protrudes so as to widen the loop 30 to form an aperture 32. Next, the leader 31 is threaded through the aperture 32 and the subsequent stages, such as the tightening of the knot 33, are the same as those envisaged by the first embodiment, described above. Yet another embodiment of the method disclosed is illustrated in Figs. 19 to 23 and differs principally in the mode of defining the aperture 32. In the embodiments described above, the aperture 32 is formed by partially withdrawing the needle 4. In the embodiment illustrated in Figs. 19 to 23, however, the loop 30 is widened. In practice, the needle 4 used for this embodiment has a first eye 41 near the point 40 and a second eye 42 further along it (on the left in the drawings). Once the needle 4 has been inserted into the border 5, which in the drawings being described is that of the bag 2, the configuration assumed by the needle and thread is that illustrated in Figs. 19 and 20 in a side view and a top view, respectively. The needle 4 has been run through the border 5 by a value L4 far enough for the eyes 41 and 42 to be both on the other side and to define the loop 30. This embodiment envisages means 7 for hooking the thread 3, the said means being represented in the drawings by a forked part. The means 7 move in a direction N (vertical in the drawings) which is substantially perpendicular to the direction in which the needle 4 passes through the border 5. As illustrated in detail in Fig. 21, the means 7 may consist of a fork shaped element with a hooking end 7 which passes through the second eye 42 when the hooking means 7 are in the active or hooking position. Basically, the loop 30 is widened by its interaction with the hooking means 7, which pull more thread to the side of the border 5 (where the loop 30 is) in such a way as to form the aperture 32, also described in the other embodiments, through which the leader 31 is to be threaded. The subsequent stages, that is, those in which the leader 31 is threaded through the aperture 32 and the resulting knot is tightened are the same as those envisaged by the embodiments illustrated in Figs. 1 to 18. The invention described can be subject to modifications and variations without thereby departing from the scope of the inventive concept. Moreover, all the details of the invention may be substituted by technically equivalent elements.

Claims: A method for attaching a tag (1) to a tea bag (2) using a piece of thread (3) fixed to the tea bag (2) at one end and to the tag (1) at the other, the said tea bag (2) and the said tag (1) both having at least one border (5) with reduced thickness, the said method being characterized in that it comprises the following stages: hooking of a first end or leader (31) of the said thread (3) by an eye (41) of a needle (4) and running of the said needle (4) and thread (3) into the said border (5) in a first direction (R) through to the opposite side of the border itself by a value (L4) sufficient to make a loop (30) in the thread (3), that is to say, to form a section where the thread is doubled up; widening of the said loop (30) by partially withdrawing the needle in such a way as to form an aperture (32) through which the free end of the leader (31) can be inserted; insertion of the said leader (31) into the aperture (32) in the loop (30) and releasing of the said thread (3) by the needle (4), the thread (3) being pulled in such a way as to tighten the resulting knot (33). The method for attaching a tag (1) to a tea bag (2) according to claim 1, characterized in that the said aperture (32) is formed by partially withdrawing the said needle (4) in a direction (R') opposite to the first direction (R) and then twisting it about its axis (X) through at least 180 degrees, leaving a doubled up section of thread on the other side, longer than the part of the needle that still protrudes so as to widen the loop (30) to form the aperture (32). The method for attaching a tag (1) to a tea bag (2) according to claim 1 characterized in that it comprises the following stages: hooking of a first end or leader (31) of the said thread (3) by a first eye (41) of a needle (4) which has a second eye (42) in addition to the said first eye (41), the second eye being located further along the needle than the first eye, which is the nearer to the needle point (40); running of the said needle (4) and thread (3) into the said border (5) in a first direction (R) so that the said first eye (41) and the said second eye (42) go right through the border itself by a value (L4) sufficient to make a loop (30) in the thread (3), that is to say, to form a section where the thread is doubled up and resting against the said needle at least at the second eye (42); widening of the said loop (30) by its interaction with hooking means (7) passing by the said second eye (42) in such a way as to form the said aperture (32); insertion of the said leader (31) into the aperture (32) in the loop (30) and releasing of the said thread (3) by the needle (4), the thread (3) being pulled in such a way as to tighten the resulting knot (33). The method for attaching a tag (1) to a tea bag (2) according to claim 2 characterized in that it comprises the following stages: after said hooking stage, partial withdrawal of the said needle (4) through the border (5) and twisting of the needle about its axis (X) through at least 180 degrees, leaving a doubled up section of thread on the other side, longer than the part of the needle that still protrudes so as to widen the loop (30) to form an aperture (32); insertion of the said leader (31) into the aperture (32) in the loop (30) and extraction of the said needle (4) so as to pull the thread (3) and tighten the resulting knot (33). The method for attaching a tag (1) to a tea bag (2) according to claim 2 characterized in that said needle (4) is a crochet needle (4) and in that it comprises the following stages: running said needle (4) through said border (5) in said direction (R') opposite to said first direction (R) before said hooking stage; after said hooking stage, partial withdrawal of the said needle (4) through the border (5) in a direction (R') opposite to the first direction (R) and then twisting of the needle about its axis (X) through at least 180 degrees, leaving a doubled up section of thread on the other side, longer than the part of the needle that still protrudes so as to widen the loop (30) to form an aperture (32); insertion of the said leader (31) into the aperture (32) in the loop (30), release of the said needle (4) from the thread (3) and pulling of the thread (3) and tighten the resulting knot (33). The method for attaching a tag (1) to a tea bag (2) according to claim 3, characterized in that the said loop (30) is widened by means (7) for hooking the said thread (3) which move in a direction (N) which is substantially perpendicular to the first direction (R) and which have a hooking element (70) at the end that passes through the second eye (42) when the hooking means (7) are in the active or hooking position. The method for attaching a tag (1) to a tea bag (2) according to claim 1 characterized in that the said hooking stage is preceded by a stage in which the thread (3) is cut to a length equal to the desired distance between the tag (1) and the bag (2) plus the length required to make at least two knots, the resulting length of thread (3) being positioned in such a manner that at least a section of it is parallel to the border (5) where it is to be fixed. The method for attaching a tag (1) to a tea bag (2) according to claim 1 characterized in that one end of the said thread (3) is fixed to the said tag (1) at the same time as its other end is fixed to the tea bag (2). The method for attaching a tag (1) to a tea bag (2) according to claim 1 characterized in that the ends of the said thread (3) are fixed to the said tag (1) and to the said tea bag (2) at different times. The method for attaching a tag (1) to a tea bag (2) according to claim 1, where the tag (1) is made of paper coated at least partially with a thermal adhesive, characterized in that, after the said knot (33) is tightened, it envisages the following: gathering up of the said thread (3) into a coil (35); heat sealing of the tag (1) to the said bag (2), with the said coil (35) between them, in such a way as to form a detachable seal between the tag (1), the coil (35) and the bag (2) so that the tag (1) can be easily pulled free of the bag (2), while the thermal adhesive remains on the tag (1).

Inventors: ROMAGNOLI ANDREA, ROMAGNOLI, ANDREA
Applicants: IMA SPA, I.M.A. INDUSTRIA MACCHINE AUTOMATICHE S.P.A.
Application year: 1995
Main classification: B65B29
IPC codes: B65C7, B65B29