Packaging device for elongated articles
The invention relates to a packaging device for elongated articles, being of the type presented in the preamble portion of the appended claim 1.
Elongated articles refer to articles in which one dimension exceeds in a particular plane the dimension which is perpendicular to the same. Examples of these articles include articles typically approximately rec- tangle-shaped in horizontal plane, for instance egg boxes. Egg boxes are usually packaged by bringing them on a conveying track to a grouping station, in which a pusher moving across the conveying track pushes them on a grouping base. Several succesive groups, i.e. rows formed of articles, are carried on the conveying track and pushed one at a time next to the preceding groups on the grouping base, wherein the articles form a layer. Such a layer is carried from the grouping base to further processing to form a package, for example to a palletizer.
Due to the length/width ratio of elongated articles, the rows of articles pushed with the pusher always form layers of particular shape in the horizontal plane. Thus, a frequently occurring situation is that the filling of the space is not optimal. For example, European application publication EP-667 310 discloses a feeding device located in connection with the palletizer, in which a particular rotating device is located after the conveying track carrying the articles. By means of this rotation device, the direction of the article can be turned 90° from the original. After this the articles are grouped on a special grouping base, on which ready- turned articles are moved with specific supporters portruding upward from underneath the base. These stages are time-consuming and re- duce the packaging capacity. The same principle is disclosed in European patent 266 619, in which a specific rotating device is provided in connection with a conveyor to turn the articles when desired.
Moreover, US patent 3,739,901 presents a grouping device for elon- gated bags of bread slices, which comprises a grouping base on which a particular grouping pattern is desired to be achieved. The desired grouping pattern is generated by means of pre-turns performed on a U- shaped conveyor. The articles which are in the correct position are
moved from the conveyor to the grouping base via one edge of the grouping base. Turning the articles by means of the conveyor before moving them on top of the grouping base is time-consuming in the same way as the system in the aforementioned reference publication.
The purpose of the invention is to introduce an improvement for these drawbacks, and according to the invention, the packaging device is primarily characterized in what will be mentioned in the characterizing part of the appended claim 1. When a conveying track carrying articles is composed of two different sections located on different sides of the grouping base and having a separate pusher each, it is possible to fill the edge which otherwise would be left incomplete due to the dimensions of the articles, with other articles brought with another pusher from another direction, articles, the longitudinal directions of which thus form an angle with respect to the articles brought with the first pusher. It is possible to transfer the articles in their correct positions directly to the grouping base, on which a complete layer is formed for further handling.
As for the other preferred embodiments of the invention the reference is made to the appended dependent claims 2 to 6, and the specification hereinbelow.
In the following, the invention will be described in more detail with ref- erence to the appended drawings, in which:
Fig. 1 shows a device according to the invention viewed from the top,
Fig. 2 shows an alternative embodiment of the device viewed from the top, and
Fig. 3 shows schematically two successive devices connected to the same product line.
Fig. 1 presents a device according to the invention and its operational principle viewed from the top. The device includes a conveying track 1 for carrying elongated articles E, such as egg boxes, to the grouping
station in such a way that the longitudinal direction of the articles coincides with the direction of the conveying track 1. The grouping station includes a horizontal grouping base 3, located next to the conveying track, on top of which the batches formed of the articles E, containing two or more articles one after the other, are pushed with the pusher located in the grouping station, when the articles are in an immobile state at the pusher on the conveying track. The conveying track is approximately at the same level with the plane of the grouping base 3, and thus the pusher moves horizontally in the transverse direction with re- spect to the conveying track and pushes the articles E in contact with their longitudinally directed side with a horizontal movement on the grouping base 3.
As shown in Fig. 1 , the conveying track 1 consists of two sections one after the other, the first section 1a which is provided with a first pusher 2a next to the same, and a following second section 1b, provided with a second pusher 2b next to the same. The sections run in such a way that the areas across which the corresponding pusher travels from outside the conveying track towards the grouping base 3 (the range of ac- tion of the pushers) extend at right angles to each other. This is achieved with a curve 4 located between the sections 1 a and 1b, wherein when travelling along the curve 4, the articles gradually turn into the direction parallel to the section 1 b.
Fig. 1 shows that there are at least two conveying tracks 1 side by side, wherein they both include a first section 1a and a second section 2a. The pushers 2a and 2b are in their extreme position outside the outermost conveying track, i.e. the conveying track 1 located farthest from the grouping base 3, and they can push the articles on all parallel con- veying tracks 1 to the conveying base with only one pushing movement. Both pushers 2a, 2b are provided with intermediate positions, wherein they are between the conveying tracks in the initial position of the push, and can push the articles from the conveying track nearest to the grouping base 3 to the grouping base. The pushers 2a, 2b can be arranged to perform a movement back and forth as well as to move up and down, wherein in the latter case, the pusher can return along upper path to the outside of the conveyor/s 1 without hampering the travel of the articles on the conveyor during its reverse motion.
The conveying tracks 1 are provided with stoppers 6, which the first articles of the rows hit in such a way that the rows remain in the range of action of the pushers. At least the stoppers of the first section 1a have to be movable between the stop position and release position. These stoppers 6 can also be movable in the longitudinal direction of the conveying tracks, as is shown with a broken line by the second section 1b, wherein it is possible to set in which area the row will arrive on the grouping base 3. The width of the thrust face of the pusher is adjust- able, for example by means of turnable flaps, wherein it does not hit the rows already on the base.
The fact that the second sections 1b of the conveying tracks are located as an extension for the first sections 1a, provides the advantage that the articles E brought in the row can either be stopped at the first pusher 2a or they can be allowed to continue as far as the second pusher 2b, depending on from which direction one wishes to fill the grouping base 3. It is also possible to feed articles when the push stage is under way. For example, when the first pusher 2a is performing a push while located between the first section 1 a of the conveying track and the grouping base 3, the articles can be carried via a conveying track 3 remaining behind it to the range of action of the second pusher 2b.
The advantage achieved with several parallel conveying tracks is, that with the help of them it is possible to generally increase the capacity. For example, when the first pusher 2a is about to push articles and is located between the conveying tracks 1 , the articles can already at this stage be carried along the outer conveying track.
As an example, Fig. 1 presents one complete layer, formed on the grouping base 3. The grouping base is limited with side guards opposite to the pushing direction (not shown), which prevent the articles from sliding off the base, but of which at least one can be moved off the layer so that the whole layer can be pushed off with a movement in the direction of the plane of the grouping base 3. In the layer a row of three articles E is pushed with the first pusher 2a to the opposite side of the grouping base, after which rows of two articles E are brought in parallel
to the range of action of the second pusher 2b, which has pushed them side by side to lie perpendicular to the ones pushed with the first pusher 2a to another area of the grouping base 3.
Fig. 2 shows another alternative to arrange the articles on the grouping base via the two sides of the grouping base 3, when the slides lie at angles to each other. Here, the first section 1a and the second section 1 b of the conveying track are composed of conveying tracks running in parallel toward the grouping base 3 and curving at the corner of the grouping base 3 to extend parallelly with the two sides of the grouping base which are at an angle of 90° with respect to each other. By this arrangement is also achieved the same possibility to group elongated articles that are parallel to the sections to the grouping base 3 by pushing them in contact with their sides from two different directions. As can be seen in the figure, the first section 1a leading to the longer side of the rectangle-shaped grouping base 3, is formed of two parallel conveying tracks, and the second section 1 b leading to the shorter side is formed of one conveying track. However, several conveying tracks can also lead to the shorter side. Furthermore, broken lines indicate the possibil- ity that after the section 1 a parallel to the longer side, there is still a third section 1c which, similarly as in Fig. 1 , forms a section curving to the shorter side of the grouping base 3 as an extension for the first section, in other words it is thus possible to push rows of articles on the grouping base 3 with corresponding pushers 2a, 2b, 2c, from three dif- ferent directions.
Fig. 3 illustrates schematically the location of the devices in a wider entity. The articles E are brought along a common feeder line 7, which branches to a feeder line 8 running to a packaging device of its own and ending in a dividing device 9, in which articles brought one after the other are divided to parallel conveying tracks 1 described in detail above. The dividing device 9 is also shown in Figs. 1 and 2. The dividing device 9 of Fig. 1 contains shifters, which move articles from the feeder line 8 to the conveying track 1 , or allow the articles to proceed to another parallel conveying track 1 functioning as a direct extension for the feeder line 8. The dividing device 9 of Fig. 2 contains shifters, which allow the articles to proceed to the conveying track of the first section
1 a, or move them either to another parallel conveying track of the same section or to the conveying track of the second section 1 b.
Fig. 3 also presents a section for further processing of the horizontal layers formed of articles. A complete layer is pushed with a pusher 5 (shown also in Fig. 1) of the whole layer located in connection with the grouping base 3, which pusher 5 has been moved aside from the articles E, in between particular tongues 10 which move it on top of a pallet located in the palletizer P, wherein vertical walls of the sales and trans- port package are already attached to the pallet, so that one side is left open to allow the transfer of the layers of articles. Thus, the pusher and the tongues form transfer means for moving the layers one on the other on top of the final transport base.
The movements of different parts can be implemented with conventional actuator solutions, for example by using pneumatic cylinders. Furthermore, it is possible to use conventional control automation solutions, such as counters, switches, etc, to supply articles, to form rows of articles to be pushed from different directions, and direct them to cor- rect locations. Similarly, it is possible to use mechanical conveyor structures known in the packaging field in the conveying tracks. The frame of the device can be provided with rails known as such, to which the actuators can be attached and which control the movements of mobile parts, such as pushers.
The pusher need not necessarily be movable up and down, but it could in principle return directly along the same horizontal line after its pushing movement, because articles can be conveyed also from behind the pusher, when the pusher is in front position. In this case, however, arti- cles cannot be stopped behind the pusher, i.e. such mere back-and- forth movement can only be used in the pusher 2a. The movement paths of the pushers and the existence of parallel conveying tracks 1 provide numerous possibilities to group the rows of articles on the grouping base 3.
Naturally, the grouping of the rows of articles shown in Fig. 1 is not the only possible, and it can be modified according to the sizes of the articles available. Furthermore, one formed layer can also contain articles
of different sizes, for example in rows of articles brought from the same direction, the articles can be of the same size, but have a different size compared with the articles of the article rows brought from another direction. Moreover, grouping can be varied in the layers superimposed in the final package, for example in the layer formed next on the grouping base 3, a row of articles brought from a different direction compared with other rows of articles can now be located on the opposite side. Thus, it is possible to avoid seams running vertically through the package and formed of the boudary points between the rows of ar- tides, and the layers of articles pile on top of each other in a more stable form.
The articles that are being handled can basically be of any size. The structure is particularly well suited for articles with such external di- mensions where in horizontal section (in the section parallel to the plane of the conveying track) the length exceeds the width. The dimension perpendicular to the horizontal section, i.e. the height, can be smaller than the width, as in egg boxes, but it can also be equal, as in many biscuit packages. The grouping principle is especially well suited for small packages sold by retail, for example such having the length below 50 cm.