EP1882581A1

EP1882581A1 - A method of applying tear tapes to a packaging material, a method of packaging coffee, a device for applying teat tapes to a packaging material and a packaging machine for packaging coffee

Info

Publication number: EP1882581A1
Application number: EP07001869A
Authority: EP
Inventors: Joachim Bellmann; Mathias May; Harald Lorenz; Gary Brooks; Ben Thompson; Vince Shaw
Original assignee: Kraft Foods R&D Inc Deutschland; Filtrona United Kingdom Ltd; Kraft Foods R&D Inc USA
Current assignee: Filtrona United Kingdom Ltd; Kraft Foods R&D Inc USA
Priority date: 2006-07-27
Filing date: 2007-01-29
Publication date: 2008-01-30
Anticipated expiration: 2027-01-29
Also published as: DE602007006729D1; ATE468965T1; PT1882581E; PL1882581T3; DK1882581T3; EP1882581B1

Abstract

A method of applying tear tapes (109) to a packaging material (105) comprises the steps of: gripping the tear tape (109, 129), moving the tear tape (109) across the packaging material (105), and cutting the tear tape (109) and pressing it to the packaging material (105).

A method of packaging coffee involves a method of applying tear tapes to a packaging material as described above.

A device (123) for applying tear tapes (109) to a packaging material (105) comprises at least one gripper (22, 24), at least one drive (16, 18, 20) for moving the gripper (22, 24) across the packaging material (105), at least one cutter (120) and at least one stamp (26) for applying the tear tapes (109) to the packaging material (105) .

A packaging machine for packaging coffee, comprises at least one such device for applying tear tapes.

Description

Technical Field

The invention relates to a method of applying tear tapes to a packaging material, a method of packaging coffee, a device for applying tear tapes to a packaging material and a packaging machine for packaging coffee.
In the field of packaging food products, such as coffee, several aspects have to be taken into account. Firstly, the food product is to be packaged hermetically. Secondly, the entire packaging operation should be performed as economically as possible. Thirdly, the consumer should be able to open the package easily.

Background Art

In the field of applying tear tapes to a packaging material, it is well known to cut a tear tape from a web of strip material and apply the cut tear tape in a direction substantially perpendicular to a machine direction, i.e. a direction, in which the packaging material is conveyed. Such a method is, for example, known from US 2,683,401 . In this process the length of the tear tape corresponds to the width of the web of strip material and the width of the tear tape corresponds to the "length" which is cut from the web of strip material.
In contrast, tear tapes are applied in the form of rolls on which the tear tape already has the desired width, for example, in accordance with DE 102 15 648 A1 . In the method and device disclosed therein, the tear tape is rolled across a packaging material by a roller and subsequently cut to the desired length.
EP 1 054 809 B1 is related to a method in which the tear tape is also supplied with the desired width and conveyed across a packaging material by a conveyor belt having through holes and "holding" the tear tape by a vacuum applied underneath the conveyor belt. However, this method of supplying the tear tape is comparably slow.
US 4,617,683 discloses a method of pushing extruded plastic profiles across a packaging material and applying as well as cutting same.
Finally, EP 05 016 623 filed July 29, 2005 by the Applicant discloses a method and a machine for packaging coffee in which a tear tape is applied across a packaging material.

Summary of the Invention

The invention provides a method of applying tear tapes to a packaging material and a method of packaging coffee which are particularly efficient. Moreover, a device for applying tear tapes to a packaging material and a packaging machine for packaging coffee are provided, which can efficiently package food stuffs, especially coffee.
Accordingly, the novel method involves gripping the tear tape, moving the tear tape across the packaging material and cutting the tear tape and pressing it to the packaging material. As the tear tape is "physically" gripped, in other words a force is applied from two sides of the tear tape, the tear tape can be moved across the packaging material significantly faster than in the previously known methods involving vacuum based conveyor belts. In connection with the movement across the packaging material, the tear tape is moved along a path spaced from the packaging material and pressed to the packaging material, essentially along the entire length of the individual tear tape, thereafter. In contrast to a method in which the tear tape is "rolled onto" the packaging material, the application of the tear tape can be accelerated as merely the tear tape has to be moved across the packaging material. Particularly, any rollers or similar devices, which also have to move across the packaging material in the previously known method, can be eliminated and the tear tape can be applied to the packaging material along its entire length by a stamp, which merely moves towards the packaging material but not necessarily parallel thereto. Moreover, in the method described herein, the tear tape can be moved, particularly drawn across the packaging material "freely", i.e. without being supported by a conveyor or the packaging material, by merely being gripped by the gripper. It is noted that the tear tape can generally be applied in a direction substantially perpendicular to the machine direction, i.e. perpendicular to the direction in which the packaging material is conveyed. However, any angles relative to the machine direction are possible.
In the final step of applying the tear tape to the packaging material, the tear tape is cut from the continuous strip of tear tape material, which can, for example, be supplied from a roll. It is noted that such a roll can contain kilometres of tear tape material. In connection with cutting the individual tear tape from the continuous strip, the tear tape is pressed to the packaging material. For this purpose, it is beneficial if the tear tape is supplied in a self-adhesive state. As regards further details of a method and a device for applying tear tapes to packaging material, reference is made to the Applicant's EP 05 016 623 filed July 29, 2005 , which is incorporated herein by reference.
Preferred embodiments of the method described herein are specified in the dependent claims.
When the tear tape is supplied in a self-adhesive state, the step of pressing the tear tape to the packaging material can be performed particularly easy as it is merely required to apply a pressing force and additional steps, such as applying heat or applying adhesive to the tear tape beforehand, can be eliminated.
In connection with the present inventive, it is also preferred to supply the tear tapes as a continuous strip material provided on rolls and having a predetermined width. Thus, the width corresponds to the width of the individual tear tape and the length of the tear tape corresponds to the length of strip material which is cut from the continuous strip.
Whereas other methods of gripping the tear tape are possible, it is preferred that the tear tape is gripped from two sides thereof. In other words, a mechanical force is applied by a gripper having two jaws between which the tear tape is gripped.
In order to achieve particularly high speeds, it is advantageous to grip the tear tape before or at the same time as a preceding tear tape is cut. Thus, the subsequent tear tape can, since it is already gripped, be moved across the packaging material quickly and immediately after the preceding tear tape has been cut.
It is particularly advantageous when the gripper is not only used to grip the tear tape but also to move the tear tape across the packaging material in a state in which the tear tape is gripped. In other words, a driving force is applied to the gripper to move or draw the gripped tear tape across the packaging material.
As regards the side of the packaging material, to which the tear tape is applied, it is currently preferred to prepare a packaging material having an inside and an outside, the outside possibly being imprinted with the branding of the final product or any other consumer information. It is, moreover, currently preferred to apply the tear tape to the inside of the package in order to "hide" the tear tape and to avoid the need of harmonizing the outside imprinting with the tear tape.
It is particularly preferred to apply the tear tape from above the packaging material. In other words, the packaging material is conveyed with that side, preferably the inside, to which the tear tape is to be applied, facing upwards. The packaging material can be supported by a suitable table or conveyor. As mentioned, the tear tape is preferably applied from above the packaging material with the table or conveyor supporting the packaging material, when the pressing force is applied.
As regards the packaging material, it is currently preferred to supply this as a paper based material in order to provide a cost effective package, for example as an outer wrapper for coffee packages having an inner bag or vacuum pack. Thus, the packaging material can, for example, be a paper/plastic laminate. It is noted that the packing material can both be supplied as a continuous web and as individual, already cut sheets.
The method described herein can be made particularly efficient when the cutting of the tear tape and pressing same to the packaging material is performed essentially simultaneously. This can, for example, be achieved by applying the pressing force by a stamp, to which a cutter is mounted. Thus, simply by moving the stamp towards the packaging material, the tear tape is pressed to the packaging material and may be cut by one and the same movement, either slightly before it is applied to the packaging material, essentially simultaneously with the application or slightly after the tear tape has been pressed to the packaging material.
In connection with cutting the tear tape, it is also found advantageous to, at least partially, cut also the packaging material. For example, one, two or more cuts may be formed adjacent the tear tape in the packaging material to help the consumer find the beginning of the tear tape and assist in beginning the tear action.
The method of packaging coffee described herein involves the method of applying tear tapes to packaging material in one of the embodiments described above, and wrapping the packaging material with the tear tape applied around an inner bag which can be a vacuum pack. Details of the method for packaging coffee can be taken from the Applicant's EP 05 016 623 filed July 29, 2005 , incorporated herein by reference.
The invention also provides a device for applying tear tapes to a packaging material comprising at least one gripper, at least one drive for moving the gripper across the packaging material, at least one cutter and at least one stamp for pressing the tear tape to the packaging material. The advantages and preferred embodiments of the device according to the invention can be taken from the above description related to the method.
In connection with the device described herein, it is particularly preferred to provide the at least one gripper as a magnetic gripper. In other words the gripper may be opened mechanically and/or closed by magnetic force which could be activated or deactivated by supplying current to an electromagnet, or vice versa, i.e. the gripper could be closed mechanically and/or opened by magnetic force.
Preferably, the at least one gripper is mounted to an endless belt acting as the drive for moving the gripper.
In order to achieve particularly high speeds with a relatively space saving arrangement, it is currently preferred to mount plural grippers to an endless belt. Thus, at a point in time when a tear tape has just been applied to the packaging material, one gripper has already gripped the subsequent tear tape, one gripper has just released the tear tape which has just been cut and applied to the packaging material, and the remaining, for example, two grippers will be in a type of standby position and will be moved to perform the following steps in the following order: gripping the tear tape, moving it across the packaging material and releasing the individual, cut and applied tear tape.
With regard to a space saving arrangement, it has turned out to be particularly beneficial when the endless belt to which the at least one gripper is mounted, surrounds the packaging material. In other words, the packaging material is conveyed "through" the loop formed by the belt. Moreover, the grippers present on the upper part of the endless belt may be used to grip the tear tape and move it across the packaging material, and the lower part of the belt can be used as the return path.
The cutter for cutting the tear tape may advantageously be provided as a replaceable cutter, to be in the position to efficiently use different types of cutters, for example, in order to provide different cutting patterns including those cuts, which are to be formed in the packaging material.
The entire process of applying the tear tapes can, as mentioned above, be streamlined if the cutter is mounted to the stamp which is provided for pressing the tear tape to the packaging material. Thus, cutting the tear tape and supplying same to the packaging material can be done essentially simultaneously.
A packaging machine for packaging coffee essentially comprises the above-described device for applying tear tapes to a packaging material as well as those further devices for packaging coffee, which are derivable from the Applicant's EP 05 016 623 filed July 29, 2005 incorporated by reference.

Brief Description of the Drawings

Hereinafter the invention will be described by nonlimiting examples thereof and with reference to the drawings in which:

Fig. 1 is a front view of a device for applying tear tapes to a packaging material;
Fig. 2 is a perspective view of the device of Fig. 1; and
Fig. 3 is a detailed perspective view of the device of Figs. 1 and 2.

Detailed description of Preferred Embodiments of the Invention

With reference to Fig. 1, the device 123 for applying tear tapes supplied as a continuous strip material 129 can include a device for accommodating at least one roll 121 of strip material 129. Individual tear tapes 109 (see Fig. 3) can be cut from the continuous strip material. The path for supplying the tear tapes may include a lace-up path formed by plural rolls 10, 12, of which at least one 12 may be moveable. The packaging material, to which the tear tapes are to be applied, is conveyed, according to the orientation shown in Fig. 1 in a horizontal orientation and in a direction substantially perpendicular to the plane of the drawing and towards the viewer of Fig. 1. To support the packaging material, a table 14 is present. An endless belt 16 wound around two rolls 18, 20 is provided and carries at least one gripper, in the embodiment shown two grippers 22, 24. In the preferred embodiment, the rolls 18, 20 are rotated in a clockwise direction, according to the orientation shown in Fig. 1, so that the "upper" gripper 24 is moved from left to right and the "lower" gripper 22 is moved from right to left. Moreover, in the embodiment shown, the device 123 comprises a stamp 26 for pressing tear tapes to the packaging material. As currently preferred, a cutter 120 is mounted to the stamp 26 and serves to cut individual tear tapes from the continuous strip material 129 as well as, if desired, the packaging material.
In the method described herein, the free end (after the preceding tear tape has been cut) of the strip material 129 is gripped, for example, by gripper 24. When this gripping takes place, the gripper 24 is at a position somewhat left of the cutter 120. Thus, Fig. 1 shows a situation in which the tear tape is being moved across the packaging material, from left to right in Fig. 1. When the gripper 24 is in the vicinity of the distal (right) end of the packaging material, the stamp 26 is moved towards the packaging material to apply the tear tape to the latter. Essentially simultaneously therewith, the individual tear tape is cut from the continuous strip material 129 by the cutter 120. At this time, the gripper 22 has moved to a position where it can grip the free end of the continuous strip material so that the next cycle, as described above, can commence. It is noted that it is currently preferred to provide multiple, such as four grippers on the endless belt, so that, for example, one gripper will be at a position in the vicinity of the distal end of the packaging material, one gripper will be in a position just left of the cutter to grip the free end, and the remaining two grippers will be on the return path provided by the lower part of the endless belt.
Fig. 2 shows a perspective view of the device of Fig. 1 with packaging material 105 being conveyed in a machine direction denoted 111. 119 denotes the inside of the packaging material 105, to which the tear tapes are preferably applied. Fig. 2 also shows a table 122 supporting the packaging material 105.
Fig. 3 is a further detailed view showing an individual tear tape 109 applied to the inside 119 of the packaging material 105 with an angle θ to the machine direction 111, i.e. the direction in which the packaging material 105 is conveyed. As mentioned above, the tear tape 109 is moved across, i.e. at an angle θ, preferably essentially perpendicular to the machine direction of the packaging material. Fig. 3 shows the situation in which the individual tear tape 109 has just been cut from the continuous strip material, and the free end 28 of the strip material has been gripped by gripper 22. As can be taken from Fig. 3, the gripper 22, as well as gripper 24, may have two jaws, between which the strip material 129 may be gripped in an essentially horizontal orientation. Those surfaces of the jaws, between which the strip material 129 is gripped, may be slightly corrugated to achieve a sufficiently strong grip. It can also be taken from Fig. 3, that the cutter 120 has not only cut the individual tear tape 109 from the continuous strip material 129, but has also made one or more cuts 30 in the packaging material in the vicinity of the tear tape to assist the consumer in finding the beginning of the tear tape and initiating the tearing action.

Claims

A method of applying tear tapes (109) to a packaging material (105), comprising the steps of:
gripping the tear tape (109, 129),

moving the tear tape (109) across the packaging material (105), and

cutting the tear tape (109) and pressing it to the packaging material (105).
The method of claim 1, wherein the tear tapes (109) are supplied in a self-adhesive state.
The method of claim 1 or 2, wherein the tear tapes are supplied as continuous strip material (129) provided on rolls (121) and having the width of the tear tapes (109).
The method of any of the preceding claims, wherein the tear tape (109, 129) is gripped from two sides thereof.
The method of any of the preceding claims, wherein the tear tape (109, 129) is gripped before a preceding tear tape (109) is cut.
The method of any of the preceding claims, wherein the tear tape (109, 129) is gripped by a gripper (22, 24) and moved across the packaging material (105) by the gripper (22, 24) in a state of being gripped by the gripper (22, 24).
The method of any of the preceding claims, wherein the packaging material has an inside (119) to which the tear tapes (109) are applied.
The method of any of the preceding claims, wherein the tear tapes (109) are applied to the packaging material (105) from above.
The method of any of the preceding claims, wherein the packaging material (105) is a paper based material.
The method of any of the preceding claims, wherein cutting and pressing the tear tape (109) to the packaging material (105) is performed essentially simultaneously.
The method of any of the preceding claims, wherein the packaging material (105) is at least partially cut together with the tear tape (109).
A method of packaging coffee including the method of applying tear tapes of one of the preceding claims.
A device (123) for applying tear tapes (109) to a packaging material (105) comprising at least one gripper (22, 24), at least one drive (16, 18, 20) for moving the gripper (22, 24) across the packaging material (105), at least one cutter (120) for cutting at least the tear tape (109) and at least one stamp (26) for applying the tear tape (109) to the packaging material (105).
The device of claim 13, wherein the gripper (22, 24) is a magnetic gripper.
The device of claim 13 or 14, wherein the at least one gripper (22, 24) is mounted to an endless belt (16) acting as the drive for moving the gripper (22, 24).
The device of any of claims 13 to 15, wherein multiple grippers (22, 24) are mounted to the endless belt (16).
The device of any of claims 12 to 16, wherein the belt (16) surrounds the packaging material (105).
The device of any of claims 12 to 17, wherein the cutter (120) is replaceable.
The device of any of claims 12 to 18, wherein the cutter (120) is mounted to the stamp (26).
A packaging machine for packaging coffee, comprising at least one device for applying tear tapes of any of claims 13 to 19.