EP1456106B1 - Method and device for forming groups of flat articles - Google Patents

Abstract

Groups are formed from flat articles being supplied in a plurality of supply streams by combining the supply streams to form a group stream, and by separating article groups from the head end of the group stream through clamping and accelerating aligned leading article edge zones. The supply streams are superimposed in at least one combining point, wherein in all streams to be combined and in all superimposed streams the articles are arranged parallel in a direction transverse to the conveying direction, have the same article spacings, and are conveyed at the same speed. Projections of the streams to be combined and of the superimposed streams on a plane parallel to the parallel alignment of the articles run parallel to one another or coincide. Projections of the streams to be combined on a plane transverse to the parallel alignment of the articles run together at an acute angle.

Description

The invention is in the field of cargo handling and general cargo processing and relates to a method and apparatus according to the preambles of the corresponding independent claims. Method and apparatus according to the invention serve to form groups of flat objects, in particular printed products, wherein the flat objects are supplied in the form of a plurality of substantially continuous streams, wherein each removed group usually contains an object from each supply stream and wherein the flat objects in the groups are arranged substantially stacked.

Said group formation is a frequently used step in the further processing of products resulting from printing presses. For example, the signatures of books are grouped into such groups or other printed product parts produced in separate printing processes, finished printed products to be combined into shipping units, or inserts to be inserted in a main product. In the process, different products are usually brought together from one another in the groups and usually one product type is supplied with each feed stream.

According to the prior art, stacked printed product groups are formed along a gathering section. In this case, the resulting groups or stacks are conveyed along the gathering route, wherein they rest one behind the other on a substantially horizontal surface or are accommodated in conveyor compartments in which the flat objects are ajar against an inclined wall. In this way, the resulting groups or stacks are conveyed past feed points, at each feed point a feed stream discharging into the gathering section and usually at each feed point to each over-conveyed group, a printed product is added.

It now turns out that the conveying of the resulting stacks or groups in succession on essentially horizontal conveyor supports is easy to implement in terms of apparatus, for example with a conveyor belt on which simple compartments succeeding one another in the conveying direction are formed. However, it also turns out that this type of gathering distance in the conveying direction is relatively long, which length depends essentially on the largest expected formats of the printed products and on the number of feeding points. Also, the supply of printed products to such consecutively funded stacks is easy to implement, for example, directly from shingled streams in which the printed products supplied with overhead, leading edges and the ever foremost item is pushed down on a stack conveyed past or falls on this. However, if large capacities are to be achieved with such devices, high conveying speeds become necessary along the gathering distance, which is energetically unfavorable. In addition, this creates strong air currents, so that held in particular for the processing of light objects of large format, the stack for the promotion, but must be released for each additional addition of a product.

The difficulties mentioned are being avoided by using the methods mentioned above, in which the printed products are conveyed in conveyor compartments (lying stacks). The extent of these conveyor compartments in the conveying direction is limited not by the largest expected format but by the largest expected stack height (sum of the thicknesses of the stacked printed products), which is significantly smaller for most applications than their areal extent (format). For the supply but the printed products must be introduced into the conveyor compartments or between the stack. For this they are usually supplied by a gripper held on an upper edge and introduced from above, that is, with the unguided, lower edge ahead, in the conveyor compartments. If the conveyor compartments are as narrow as possible to shorten the gathering distance, the space for the supply is small and the supply must be carried out accordingly precisely. This requires, on the one hand, a small relative speed between the conveying compartment and the object to be added, and thus a relatively long addition route and an absolute speed limited above of the printed product to be added, so that its unguided edge, which is leading during the supply, is not moved uncontrolled by the air flow. It thus turns out that with the second method, which is considerably more expensive in terms of apparatus than the former, the difficulties listed at the outset can only partially be solved.

A combination of device-like simplicity and short, ie space-saving gathering distance (narrow stacking arrangement and near successive Zuführungsstellen) is conceivable when the stacks are overlapping, that is promoted in the manner of a shingled stacking stream, ie in a stream that is on a substantially horizontal conveyor support rests and in which each scale consists of a plurality of stacked (stacked) objects. Solutions in this direction are described in the publications DE-3145491 (or US-4471953, F125) and DE-19643395 (or US-5727781, F425).

According to DE-3145491, the overlapping stacks are conveyed along the gathering section by means of stack grippers which engage the trailing stack sides. The objects of a following stack can cover a leading stack gripper. For the addition of a further article to a batch conveyed in this way, the corresponding stacking gripper is opened upwards and lifts the objects of the trailing stack which cover it. The articles to be deposited on the stacks are individually fed at upper leading edges in a feeding direction rectified with the conveying direction of the gathering line, their speed being slower than the speed of the shingled stacks on the gathering line. The feed is controlled such that the unguided trailing edge of an object to be supplied is positioned on a guide surface or on an already stacked object and pushed by the speed difference in the stack gripper and thereby also under the raised objects of the trailing stack. Once this trailing edge of the object to be added strikes the gripper body and is thus aligned with the trailing edges already stacked objects stacked gripper, the feeding gripper is opened and the stack gripper closed.

The above short description shows that according to DE-3145491 a relatively simple stacking conveyance with small stacking distances becomes possible. However, the feed points can not be arranged close to one another in the direction of staple conveying, the device is expensive and the feed points have to be equipped depending on the format.

Publication DE-19643395 also proposes a collating method based on the idea of a scaly stack flow. The supplied at a feed point, rectangular or optionally square printed products are not actually on a conveyed over, resulting stack but they are placed in the form of a scale flow on a possibly already consisting of several shingled streams group stream. In this case, all the scale flows superimposed in the group flow have the same scale spacing and leading ranges of the printed products of each group are aligned with each other but separated from each other by trailing areas of printed products of leading groups. At a head end of this shingled group stream, where leading portions of printed products belonging to a leading group lie on top of each other (there is no leading group whose objects are in-between), these leading portions are detected and accelerated, pulling the group out of the group stream as a stack and is separated from this.

In order to align the printed products belonging to a group to be formed but to different superimposed scale streams for a problem-free group separation relative to one another, it is proposed in DE-19643395 to guide the stack preformed in the group stream laterally. This is possible because the printed products in the group stream are conveyed diagonally, ie with a leading corner. The longitudinal edges of a scale flow of diagonally conveyed, rectangular or square printed products are not rectilinear but jagged, so that the individual scales on both sides of the stream can be performed with acting on the teeth guide means (eg mitgeförderte guide pin) in the areas of their opposite each other transverse to the conveying direction corners ,

The printed products to be supplied to the diagonal dandy group stream are fed into feed streams in which the product edges are oriented perpendicular to the conveying direction and which obliquely strike the stack stream, and each printed product is deflected in the direction of diagonal conveying for its positioning on the group stream. For this diversion forces are to exert pressure on the printed products which are picked up by the guide pins.

The position of the guide pins is to be aligned to the largest expected format of printed products to be stacked and to the scale distance. All small-sized products are aligned depending on the feed direction on one or the other of the guided corners and guided only on one side, very small products may remain completely unguided. Feeds are only possible from above and in the feed streams the leading edges must be overhead.

The invention now has for its object to provide a method and a device which serve to form groups of flat objects fed in feed streams and which, like the system according to DE-19643395, are based on a group stream consisting of a plurality of superimposed imbricated streams , However, compared with the prior art, the method and device according to the invention should make improvements not only in terms of format independence, flexibility and device-like simplicity but also in terms of shortness of the gathering path. In particular, the orientation of the objects in the groups to be formed should be much less fixed by the method or the device but should be largely adaptable to the properties of the objects and the stack stability.

The stated object is achieved by the method and the device as defined in the corresponding patent claims.

According to the invention, the flat objects from which groups are to be formed are fed into feed streams by merging the feed streams a group stream is formed, in which a plurality of scale flows lie on one another, and groups are separated from the group stream from the head end of the group stream by gripping successive, leading object areas and by accelerating the objects grasped, as is done according to DE-19643395. However, the objects in the feed streams with respect to orientation relative to the conveying direction and with respect to distance from each other are already arranged as they should be arranged in the group stream and the feed streams are brought together substantially without change of direction parallel to the areal extent of the objects. This means that no substantial forces act on the flat objects at the feed points, in particular no forces which would impair the relative arrangement of the objects to one another in these streams. For this reason, it is unnecessary to guide the flat objects laterally in the feed streams, in the merge or in the group stream.

The group stream and the feed streams are conveyed on corresponding conveyor supports. At least immediately before a merging point, in which a feed stream flows into the group stream or into another feed stream, the conveying supports and thus the objects of the merged and merged streams are arranged parallel to the conveying direction parallel to one another, the projections of the streams extend on a plane parallel to said parallel alignment of the conveyor supports parallel to each other or coincide and run the projections of the streams on a plane perpendicular to the parallel orientation of the conveyor supports at an acute angle to each other. In all the streams involved, the distance between the objects (scale distance) and the speed are the same and the merging is provided with suitable means to ensure that the streams are in phase such that edge portions of the articles of different shingled streams leading in the group stream are aligned.

At the head end of the group stream, the leading edge areas are detected and accelerated by a clamping and accelerating means acting over the entire width of the group stream, while the objects of at least one next group are pressed in such a way that they are not accelerated with the group to be separated and thus relative to the group stream can be moved.

In contrast to the system disclosed in DE-19643395, according to the invention, it is possible to combine objects having shapes other than rectangular or square in arbitrary orientations within wide limits relative to each other, and not only stack the articles in the groups, but also side by side or partly on top of each other and partly next to each other. As long as the width of the bearing surfaces is sufficient, format changes are possible without device-related changes.

So it can be made of very different sizes, different thickness and different stiff objects stable groups. In shingled feed streams, the articles may be conveyed with underlying or overhead leading edges and the feed streams may be directed from one side or the other (from below and from above) against the group stream. From these properties of the inventive method results not only the required format independence and flexibility but also the ability to arrange the feed points very close to one another, resulting in a short "gathering distance".

The device for carrying out the method according to the invention can be realized with the simplest means, for example with a system of conveyor belts and / or conveyor belt pairs for merging the feed streams, with one Pressing means at the head end of the group stream immediately before the separation point and with a separating agent acting at the separation point, wherein the pressing means and the release agent can be formed as pairs of press belts can be pressed against each other. All conveying means before the separation point have the same first speed, the clamping and accelerating means has a relation to the first speed increased speed, which is adapted to the ratio of the length of the objects in the conveying direction to the scale spacing.

Figur 1

eine Mehrzahl von Zuführungsströmen von verschieden grossen und verschieden-formatigen flachen Gegenständen und eine daraus gebildete Gruppe;

Figur 2

eine weitere Mehrzahl von Schuppenströmen von rechteckigen und quadratischen, flachen Gegenständen und zwei daraus gebildete Gruppen;

Figur 3

Teile einer beispielhaften Ausführungsform der erfindungsgemässen Vorrichtung zur Abtrennung von Gruppen vom Kopfende des Gruppenstromes (Schnitt parallel zur Förderrichtung);

Figur 4

die Vorrichtungsteile gemäss Figur 3 in einer schematischen dreidimensionalen Darstellung mit einem Gruppenstrom, in dem die flachen Gegenstände seitlich gegeneinander versetzt, das heisst weder auf eine Mittellinie noch auf eine seitliche Kante ausgerichtet sind;

Figur 5

Teile einer beispielhaften Ausführungsform der erfindungsgemässen Vorrichtung zur Zusammenführung einer Mehrzahl von Zuführungsströmen zu einem Gruppenstrom.

Method and apparatus according to the invention will be described in detail with reference to the following figures. Showing:

FIG. 1

a plurality of supply streams of different sized and different-sized flat objects and a group formed therefrom;

FIG. 2

another plurality of scale flows of rectangular and square flat objects and two groups formed therefrom;

FIG. 3

Parts of an exemplary embodiment of the device according to the invention for the separation of groups from the top end of the group stream (section parallel to the conveying direction);

FIG. 4

3 shows the device parts according to FIG. 3 in a schematic three-dimensional representation with a group flow in which the flat objects are offset laterally relative to one another, that is to say they are aligned neither with a center line nor with a lateral edge;

FIG. 5

Parts of an exemplary embodiment of the inventive device for merging a plurality of feed streams to a group stream.

Figure 1 shows parts of four exemplary feed streams 1.1, 1.2, 1.3 and 1.4 of four different types of flat objects 11, 12, 13 and 14. The feed streams are shown in an arrangement as the inventive method for merging into a (not shown) required group stream. Also shown is a group 2 separated from the group stream having, from each feed stream 1.1 to 1.4, an article 11, 12, 13 and 14, leading leading edge regions of the articles in the group being aligned and the lateral arrangement of the articles in the group corresponds to the relative location of the feed streams prior to merging.

The arrows F.1, F.2, F.3 and F.4 and the dot-dash line L.1 represent the conveying directions of the scale flows (aligned with the centers of gravity of the objects), which are dash-dotted lines L.2 to L.4 Projections of the dotted line L.1 on the conveying path of the feed streams F.2 to F.4. To illustrate the format independence and flexibility of the inventive method, the objects 11 of the feed stream 1.1 are rectangular, the objects 12 of the feed stream 1.2 triangular, the objects 13 of the feed stream 1.3 rectangular and the objects 14 of the feed stream 1.4 round. All feed streams 1.1 to 1.4 are shingled streams (distance between the articles smaller than the length of the articles in the conveying direction). In the feed stream 1.1, the leading edge regions are at the bottom, in the other shingled streams overhead. In all four scale flows, the objects lie substantially in planes transversely to the paper plane of the figure and the conveying directions are parallel to this plane of the paper. For the merges, not shown, the conveying directions are still fed parallel to the paper plane at an acute angle to each other, as indicated by the dashed lines L.1 to L.4, and the objects are still in planes transverse to the paper plane.

In all feed streams, the leading edge regions of the articles are equidistant from each other (scale spacing) and the feed streams are aligned (synchronized) such that the leading edge regions of the articles of merged feed streams are substantially one above the other.

In group 2, the objects 12 and 13 lie eccentrically between the objects 11 and 14. This is achieved by a displacement of the feed streams 1.2 and 1.3 transversely to the conveying direction (distance between the arrows F.2 and F.3 of the dotted lines L) .2 or L.3). Obviously, the method according to the invention in no way restricts the format of the objects to be assembled in a group and also does not restrict their relative, lateral arrangement in the group (arrangement transverse to the conveying direction). The only condition is that leading edge regions of objects belonging to a group are substantially aligned (so accurate that they can be detected when the groups are separated).

FIG. 2 shows in section (areal extent of the objects transversely to the plane of the paper) a group stream 3 formed from four superimposed feed streams 1.5 to 1.8, wherein the feed streams consist of differently sized, rectangular and flat objects 15 to 18. The feed streams are in the group stream directly to each other; in Figure 2, they are shown spaced from each other. The orientation of the leading edge regions of all feed streams is clearly evident therefrom. Further, Figure 2 shows two exemplary groups 2.1 and 2.2, which can be formed from the group stream 3 depending on the lateral orientation of the feed streams. In both groups, the leading edges are aligned. In group 2.1 the objects are 15 to 18 arranged on a common center line, in the group 2.2 they are aligned on a lateral edge.

FIG. 3 likewise shows, in a section parallel to the conveying direction, those parts of an exemplary embodiment of the device according to the invention which are arranged in the region of the head end of the group stream 3 and essentially serve to separate groups 2 from this head end. The group stream is conveyed on a conveyor support 20 against its head end. Immediately upstream of the head end of the group stream 3, a pressing means 21 is provided, for example, with the group flow follower pressing elements 22, whose distance from one another corresponds to the scale spacing in the group stream 3 and through which the group flow is pressed against the conveyor pad 20.

At the head end of the group stream 3, a clamping and accelerating means 23 is provided for the separation of groups, for example in the form of a press wheel 24 which cooperates with a Wegförderauflage 25 and which has recesses 26 at its periphery, such that it rotates a rhythmic sequence of generated from each other temporally spaced pressing steps in which it is pressed against the Wegförderauflage 25. Instead of the press wheel 26 and successively conveyed at the head end of the group stream 3 over and this gripping gripper can be used as clamping and accelerating means for use.

The Wegförderauflage 25 and the pressing peripheral parts of the press wheel 26 have the same speed, which is at least as much greater than the speed of the group stream 3 and the conveyor pad 20 and the pressing elements 21 that a group to be separated 2 is promoted so far in a conveyor cycle in that the trailing edge also corresponds to the longest article in the conveying direction is pulled out of the group stream 3. While the group stream 3 is conveyed in a conveying cycle by a scale distance, the separated groups must be conveyed away in a conveying cycle at least by the length of the group in the conveying direction. The rhythm of the pressing steps is to be matched to the scale spacing in the group stream 3.

The distance between the downstream end of the action of the pressing means and the clamping and the head end of the group stream 3 is advantageously to be chosen such that the trailing portions of the objects of the group to be separated from this effect are no longer exposed.

The pressing force to be generated by the clamping and accelerating means is large enough to pull the objects of the foremost group out of the group stream 3 as far as possible without slippage. The pressing force to be generated between the pressing means 21 and the conveying support 20 is large enough to prevent entrainment of objects with a group to be separated, to which they do not belong, due to mutual friction of the objects in and between the scale flows.

Figure 4 shows a schematic, three-dimensional representation of the pressing means 21 for the compression of the head end of the group stream 3 against the Weiterförderauflage 20 and the clamping and accelerating means 23 for the separation of the groups 2 from the head end of the group stream 3. Both agents act advantageously over the whole For example, as shown, they consist of rows of pressing elements or clamping and accelerating elements which are arranged transversely to the conveying direction and can be actuated substantially independently of the local thickness of the group stream 3 or group 2 (for example pressed against the conveying surface) , All these elements are advantageous displaceable transversely to the conveying direction and thereby adjustable so that they do not act on object edges.

The objects in the group 2 shown in FIG. 4 are laterally offset from one another, that is to say they are not aligned with a common center line or with a common longitudinal edge, as shown in FIG. Such a laterally offset arrangement makes it imperative that both the pressing means and the clamping and accelerating means act as possible over the entire width of the group stream. With such a laterally offset arrangement but can be ensured that the groups have a thickness as uniform as possible over the width and that, for example, thick folding edges do not destabilize objects lying on each other.

The separation of the groups from the top end of the group stream may have the same direction as the promotion of the group stream towards its head end or it may be at an angle to this direction of conveyance.

FIG. 5 shows, in a very schematic manner (section parallel to the conveying direction), the parts of an exemplary embodiment of the device according to the invention, which serve to combine feed streams (1.1 to 1.3) into a group stream 3. These parts are simple conveyor belts and conveyor belt pairs that can be pressed against each other. The figure illustrates how close to each other the merging points can be arranged in such a device.

Claims (16)

1. Method for forming groups (2) of flat articles (11 to 18), wherein the articles are supplied in a plurality of supply streams (1.1 to 1.8), wherein the supply streams (1.1 to 1.8) are combined to form a group stream (3) comprising a plurality of superimposed, imbricated streams all having the same scale spacings and aligned leading edge zones of the articles (11 to 18), and wherein groups (2) of articles (11-18) are separated from a head end of the group stream (3) by clamping and accelerating the aligned leading edge zones, characterized in that the supply streams (1.1 to 1.8) are superimposed in at least one combining point, wherein in all streams to be combined and in all superimposed streams, the articles (11 to 18) are aligned parallel to one another in a direction transverse to the conveying direction, have the same distance between one another, and are conveyed with the same speed, wherein projections of the streams to be combined and of the superimposed streams (1.1 to 1.8 and 3) on a plane parallel to the parallel alignment of the articles (11 to 18) run parallel to one another or coincide, wherein the projections of the streams to be combined (1.1 to 1.8) on a plane transverse to the parallel alignment of the articles (11 to 18) run together at an acute angle and wherein the streams to be combined (1.1 to 1.8) are synchronized in such a manner, that during superimposition of the streams, leading edge zones of the articles (11 to 18) are substantially aligned to one another.
2. Method according to claim 1, characterized in that the articles (11 to 18) in the streams to be combined (1.1 to 1.8) comprise sizes and/or shapes differing from one another.
3. Method according to claim 2, characterized in that at least in a part of the supply streams (1.1 to 1.8) the articles (11 to 18) are conveyed with leading edges aligned transverse to the conveying direction.
4. Method according to one of claims 1 to 3, characterized in that of the superimposed streams in the group stream (3) one part comprises leading article edge zones positioned on a lower stream surface and one part comprises leading article edge zones lying on a top surface of the stream.
5. Method according to one of claims 1 to 4, characterized in that a distance between projections of the streams to be combined (1.1 to 1.8) on a plane parallel to the parallel alignment of the articles (11 to 18) and a lateral displacement of the articles (11 to 18) in the groups (2) is adjustable in dependence of the article thickness.
6. Method according to one of claims 1 to 5, characterized in that the group stream (3) is pressed upstream of its head end.
7. Method according to claim 6, characterized in that the group stream (3) is pressed at pressing points being distanced from one another in the conveying direction, the pressing points being moved together with the group stream (3), wherein the distances between the pressing points are equal to the distance between the articles (11 to 18) in the superimposed streams of the group stream (3).
8. Method according to claim 6 or 7, characterized in that the group stream (3) is pressed at pressing points being distanced from one another transverse to the conveying direction, wherein the pressing points are adjustable transverse to the conveying direction in dependence of positions of article edges.
9. Method according to one of claims 1 to 7, characterized in that the leading edge zones at the head end of the group stream (3) are clamped at clamping points being distanced from one another transverse to the conveying direction.
10. Method according to claim 9, characterized in that the clamping points are adjustable transverse to the conveying direction in dependence of article widths.
11. Device for forming groups (2) of flat articles (11 to 18), which device comprises supply means for conveying a plurality of supply streams (1.1 to 1.8), means for combining the supply streams (1.1 to 1.8) to form a group stream (3), in which a plurality of imbricated streams are superimposed, a conveying-on means for transporting the group stream (3) and a clamping and accelerating means for separating the groups (2) from the head end of the group stream (3), characterized in that the means for combining comprises at least one combining point, at least two supplying conveying surfaces being arranged to lead towards the combining point and one conveying-on conveying surface being arranged to lead away from the combining point, wherein all conveying surfaces of the combining point are aligned in parallel in a direction transverse to the conveying direction and are able to be driven with a same speed in the conveying direction, wherein projections of the supplying and conveying-on conveying surfaces on a plane parallel to the parallel alignment of the conveying surfaces are aligned in parallel or coincide, wherein projections of the supplying conveying surfaces on a plane transverse to the parallel alignment of the conveying surfaces run together at an acute angle, and wherein the device further comprises means for synchronizing the supply streams (1.1 to 1.8).
12. Device according to claim 11, characterized in that, for pressing the group stream (3), a pressing means (21) is provided in the zone of the head end of the group stream.
13. Device according to claim 12, characterized in that the pressing means (21) comprises an arrangement of pressing elements (22) being distanced from one another in the conveying direction and which being arranged to be moved together with the group stream (3).
14. Device according to claim 13, characterized in that rows of pressing elements (22) distanced from one another are arranged transverse to the conveying direction, the positions of the pressing elements being adjustable over the width of the group stream (3).
15. Device according to one of claims 11 to 14, characterized in that, for being able to act in a plurality of clamping points being distanced from each other transverse to the conveying direction of the group stream (3), the clamping and accelerating means comprises a plurality of clamping elements being distanced from each other transverse to the conveying direction of the group stream (3).
16. Device according to claim 15, characterized in that the clamping elements are arranged being displaceable transverse to the conveying direction of the group stream (3).

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