EP0043030B1

EP0043030B1 - Packaging comprising a flexible band including transversely applied suction tubes

Info

Publication number: EP0043030B1
Application number: EP81104637A
Authority: EP
Inventors: Gerhard Soyez
Original assignee: Tetra Pak AB; Tetra Pak International AB
Current assignee: Tetra Pak AB
Priority date: 1980-07-01
Filing date: 1981-06-16
Publication date: 1985-08-28
Also published as: MX152966A; ZA814171B; ES267747Y; BR8104172A; PT73256A; EP0043030A1; ES267747U; DK152805C; ATE15173T1; CA1151120A; DK152805B; SE8004843L; PT73256B; DE3172021D1; DK272481A

Abstract

Coherent bands (1) of suction tubes (2) wrapped in individual protective envelopes are used to make possible the mechanical and automatic application of suction tubes to individual packing containers. The bands consist of two strips (7) of flexible plastic material which are sealed to one another and between them enclose the suction tubes. To facilitate the separation of tne suction tubes and surrounding protective envelopes from the band on application to the packing containers, the suction tube band is provided in accordance with the invention with transverse cuts (6) situated between the suction tubes which at their ends lead into further cuts which extend in longitudinal direction of the band or have a certain length in the said direction. The individual protective envelopes entering into the suction tube band are thus held together solely by two parts situated at a distance from one another and extending bandlike between the envelopes which can be cut through comparatively simply on application to the individual packing containers.

Description

Flexible bands with transversely applied suction tubes (hereinafter called "suction tube bands") are used in the packaging industry to make possible the mechanical and automatic application of suction tubes to packing containers. The suction tube band comprises suction tubes which are wrapped in individual protective envelopes adapted to the shape of the suction tube. The protective envelopes in turn are joined to one another so that a band of coherent, wrapped, suction tubes is formed. The wrapped suction tubes arranged transversely in relation to the band are evenly spaced. The protective envelopes may be in the form of separate sleeves, which are joined to one another by means of narrow bands or strips of paper or plastics, but they may also constitute integrated parts of the flexible band. A suction tube band thus may comprise two webs of plastic material between which the suction tubes are placed. The webs are joined to one another at least in the zones surrounding the suction tubes and are held enclosed in individual, closed protective envelopes.
Suction tube bands of the type described above are used to make possible the mechanical and automatic application of individual suction tubes wrapped in the protective envelopes to packing containers e.g. for juice or other beverages which are intended to be drunk directly from the packing container with the help of suction tubes. To facilitate the automatic handling of the wrapped suction tubes, the suction tubes are fed to the machine in the form of the said suction tube band, whereupon the machine separates one wrapped suction tube at a time from the band and transfers and applies it to a packing container passing through the machine. A machine of this type is described e.g. in SE-A-780 10 67-5.
As the suction tube band is in the form of two plastic webs sealed to one another, between which are enclosed the suction tubes, certain difficulties arise sometimes for the application machine or the applicator in separating the individual, wrapped suction tubes from the suction tube band. These difficulties are associated with the fact that the demand for accurate and exact cutting off of the individual protective sleeves is difficult to combine with the high operating speed of the applicator. Moreover, the plastic material of which the suction tube band is made is comparatively tough and difficult to break up, causing the material to stretch, so that the severing is rendered more difficult and the cut will be incomplete or end up in an incorrect position, which involves the risk of the protective envelope being broken, so that it can no longer fulfil its object of protecting the wrapped suction tube from contaminations.
For avoiding such difficulties as mentioned before it already is known (DE-A 1-28 47 168) to provide the flexible band of such a packaging with transverse cuts between adjacent suction tubes which cuts at some distance from the longitudinal edges of the band meet further cuts that in the longitudinal direction of the band are of a manytimes greater extent than the width of said transverse cut. With the provision of such cuts between the adjacent suction tubes of the band the separation of the individual protective envelopes from each other in an applicator of the kind as described in SE-A-780 10 67-5 will be facilitated when the applicator operates at high speed.
With a packaging comprising a flexible band of this known kind there are accordingly present two strips or bridges which extend at a distance from one another parallel along the longitudinal edges of the band to thusly ensure that the individual suction tube envelopes are held together. These strips or bridges further serve the purpose of acting as a feed and guiding means of the packaging during its handling by such an applicator in which these strips or bridges collaborate with respective feed and guiding elements of the applicator. In this respect there still exists the problem, however, that with a feed and guiding of the band accordingly along its two longitudinal edges the severing of such strips or bridges serving the separation of the individual suction tube envelopes from the band may considerably be hindered. Due to the stretching capacity of the band material which usually is a thermoplastic material there further exists with such known bands the risk that during their handling in the applicator the linear cuts which are provided at the two ends of each transverse cut are unintentionally widened or extended to the longitudinal edges of the band as soon as it will be stressed during its feed and guiding through the applicator still prior to the moment when this severing takes place.
It is accordingly an object of the present invention to provide a packaging comprising a flexible band of the kind as referred in the preamble of claim 1 which overcomes the aforementioned disadvantages that still exist with the handling of such packages especially by a machine of the kind as described in SE-A-789 10 67-5.
In accordance with the invention there is provided a packaging comprising a flexible band of the kind referred which is provided with further transverse cuts extending from the longitudinal edges of the band and also between adjacent suction tubes which further transverse cuts are terminated by further cuts which in the longitudinal direction of the band are also of a many times greater extent than the width of these further transverse cuts.
By providing the band with such further transverse and longitudinal cuts there are now obtained strips or bridges for holding together the individual suction tube envelopes that are situated a small distance inside the two iongi- tudinal edges of the band. This particular situation of the strips or bridges as accordingly spaced from the longitudinal edges of the band still secures an effective feed and guiding of the band through the collaboration between the feed and guiding elements of the applicator which thereby only have to be displaced over a corresponding distance and secures on the other side at the same time an improved severing possibility of these strips or bridges without being effected by or hindering the feed of the band.
Since with such a situation of said strips or bridges their width being effective for holding together the individual suction tube envelopes is being reduced the inventive packaging could preferably be further provided with the feature of the subsidiary claim 2. In accordingly providing all existing further cuts with either a circular or a triangular form it thereby will additionally be secured that no unintentional widening of these further cuts takes place during the handling of the inventive packaging in an applicator of the kind as described in SE-A-780 10 67-5.
A packaging with a flexible suction tube band in accordance with the invention will now be described in greater detail with special reference to the enclosed schematic drawing which only shows the details necessary for an understanding of the invention.

Figure 1 shows part of a suction tube band in accordance with a known embodiment of the invention.
Figures 2, 3 4 and 5 show embodiments of the suction tube band in accordance with the invention.

The suction tube band as shown in fig. 1 comprises a band 1 which consists of two webs of thermoplastic material of equal width placed against each other. The suction tube band I comprises moreover suction tubes 2 which are placed between the said thermoplastic material webs and are wholly enclosed by the same. The suction tubes 2 are placed transversely in relation to the band 1, that is to say substantially at right angles to the longitudinal edges 3 and 4 of the band 1. The two webs forming the band 1 are of a width which somewhat exceeds the length of the suction tubes 2, thus making it possible to seal the two webs to one another in a zone (which is indicated as a hatched area in figure 1, corresponding zones existing also in the other embodiments shown, but having been left out in figures 2-5, so as not to impair the clarity of the figures) which wholly encloses each individual suction tube 2, so that each suction tube 2 is enclosed in an airtight suction tube envelope 5.
To facilitate the separation of the individual suction tube envelopes 5 from the coherent suction tube band 1 on application of a suction tube wrapped in an envelope to a packing container with the help e.g. of the suction tube applicator, which is shown in SE-A-780 10 67-5, the suction tube band is further provided between each individual suction tube with a transverse cut 6, which linearly cuts through the two webs forming the band 1 in the sealed region between the individual, airtight suction tube envelopes 5. The cut 6 extends transversely over the suction tube band 1 but terminates at some distances inside the two longitudinal edges 3, 4 of the band 1, so that two strips or bridges 7 are formed in the band material which strips or bridges hold together the individual suction tube envelopes to a coherent band. The two strips 7 extend at a distance from one another parallel along the longitudinal edges 3, 4, of the suction tube band, thus ensuring that the individual suction tube envelopes 5 maintain their correct position in the suction tube band so that the latter obtains a rope-ladderlike form.
The provision of cuts 6, which are produced with the help of heated knives in connection with the heat-sealing of the two webs to one another, facilitates appreciably the subsequent separation of the individual suction tube envelopes 5 from the suction tube band in the applicator. In the said separation only a cutting through or punching through of the relatively narrow strips or bridges 7 is required which remain between end points of the cut 6 and the two longitudinal edges 3, 4 of the suction tube band. This cutting through can be carried out relatively simply compared with a cutting over the whole width of the band. During continuous operation at high speed certain difficulties arise when the two necessary cuts have to be placed through the strips 7 in the extension of the cut 6 made previously, so that a complete separation is achieved. This is connected with the capacity of the suction tube band to stretch and, altogether, its flexible construction which renders difficult a cutting through with the high precision which is desirable if the cuts are to coincide. To overcome this difficulty, the suction tube band is also provided with further cuts 8 which, like the cuts 6, are brought about with the help of heated cutting elements in connection with the manufacture of the suction tube band, and are placed at the positions at some distance inside the two longitudinal edges 3, 4 of the suction tube band where the end points of the cuts 6 are situated. Each cut 6 thus meets at some distance inside the longitudinal edges of the band at both its ends cuts 8 which seen in longitudinal direction of the band 1 take up a many times greater extent than the said transverse cut 6, whose main direction is in fact transversely in relation to the band 1. The width of the cuts 6 is negligible and merely corresponds to the necessary thickness of the heated knife by means of which they are produced. The cuts 8 are linear and extend substantially at right angles to the cuts 6, that is to say, the cuts 8 extend in the longitudinal direction of the suction tube band 1. By the provision of the cuts, the punching through of the strips 7 in the applicator is facilitated appreciably, since the punching no longer needs to be done with the same precision. To ensure a complete separation of a suction tube envelope 5 from the remaining suction tube band 1 it is now only necessary for the cut, which severs the strips 7, to meet or cross at some place the respective cut 8 and the placing of the cut will no longer be critical. The length of the cuts 8 determines the tolerance which can be allowed in the placing of the separating cut through the strips 7, and the cuts 8 are made therefore as long as is possible without any risk of their reaching or negatively influencing the unsealed region of the suction tube band 1 which forms the airtight suction tube envelope 5.
Turning now to fig. 2, there it is shown that each cut 6 may also end in accordance with a sub- feature of the present invention in circular holes 9 which serve as a "hollow recess" to prevent that on stressing of the suction tube band the cut 6 is unintentionally widened or extended to the edge of the suction tube band. The hole 9 is obtained in the same manner as the linear cuts 8 described earlier, at the same time as when the cut 6 is produced with the help of a heated knife or punching element, during the manufacture of the suction tube band. In connection therewith, however, waste material is produced which must be taken care of so as not to affect the manufacturing process by acting as an obstacle and diminishing the rate of production.
These endside "hollow recesses" may instead also be provided, as shown in figure 3, with a substantially triangular form. A triangular hole 10 has the advantage over the circular hole 9 that it has a distinctly limited area which makes it possible to produce the hole by melting off the thermoplastic material in connection with the production of the cut 6. Consequently the handling and taking care of waste material during the manufacture of the suction tube band can be avoided.
The extension of each hole 9 or 10, seen in longitudinal direction of the band 1, has to be greater than the corresponding width of the cut 6, so that the placing of the supplementary cuts, in connection with the separation of the individual suction tube envelopes from the band, is facilitated. The shape of the hole is such that the hole serves as a recess at the end of the cutting line. A hole of approx. 5 mm diameter has been found to be satisfactory and appreciably increases the area within which the supplementary cuts can be placed, since normally the width of the main cut will be less than 1 mm. The distance between two suction tubes located next to each other is typically 15 mm.
Turning now to figures 4 and 5 showing the main embodiments of the suction tube band in accordance with the invention, it may be seen that the strips or bridges 7, which hold together the individual, airtight suction tube envelopes 5 to a coherent suction tube band, are situated here a small distance inside the two edges 3, and 4 of the suction tube band. The reason for this is that the feed and the guiding of the suction tube band through the applicator should be possible, through the collaboration between the feed and guiding elements of the applicator and edge area of the suction tube band, without the severing of the strips 7 being affected by or hindering the feed. This has been achieved in accordance with the invention in that further transverse cuts 6' extend from the edges 3, 4 of the web inwards between two suction tubes 2, which cuts 6' are terminated by further cuts 8' which in longitudinal direction of the suction tube band 1 take up a many times greater extent than the said cuts 6'. The two cuts 8 and 8' accordingly together demarcate the strips or bridges 7 holding together the suction tube envelopes, and in the subsequent separation of the individual suction tube envelopes from the suction tube band in the applicator, the severing may be carried out anywhere along the whole length of the strips 7, thus reducing the need for precision and ensuring good and faultless functioning of the applicator.
As indicated in figure 5, the cuts 8' may also enclose removed portions of the band, so that the cuts substantially obtain the form of circular holes 9'. This will secure the same advantages as described above with respect to the holes 9 and 10 provided at the ends of the cut 6. By the invention a suction tube band is provided which, in spite of being easy to handle and extremely simple, can be broken up into individual suction tube envelopes with the help of a suction tube applicator of known type. Owing to the design of the suction tube band, the division into individual suction tube envelopes may be done at great speed without safety being endangered, and, owing to the special design of the suction tube band, moreover, optimum operational safety is achieved, even if the position of the band, owing to its flexibility, varies within wide limits of the instant of severance.

Claims

1. Packaging comprising a flexible band (1) including transversely placed suction tubes (2) wherein the band (1) is provided between adjacent suction tubes (2) with transverse cuts (6) which at some distance from the longitudinal edges (3, 4) of the band (1) meet further cuts (8) which, in the longitudinal direction of the band (1), are of a many times greater extent than the width of said transverse cuts (6), characterized in that further transverse cuts (6') are provided as extending from the longitudinal edges (3,4) of the band (1) between adjacent suction tubes (2) which further transverse cuts (6') are terminated by further cuts (8') which, in the longitudinal direction of the band (1), are also of many times greater extent than the width of said further transverse cuts (6').

2. Packaging in accordance with claim 1, characterized in that said further cuts (8, 8') enclose removed portions of the board, e.g. of a circular form (9, 9').