EP1593621B1 - Stacking device - Google Patents

Abstract

The device for the forming of stacks (10) of flat products, especially paper products has at least two stacking tables (42) which move along a circuit-like table orbit (68). The stacking tables at least segment-wise are flexible and therefore in their form are conformable to the curves (99,102,116,130) of the table orbit at least segment-wise and at least in sub-sections. In a stacking section (44) the table orbit between the receiving section and delivery section (46) extends in a straight line, and the stacking tables in the stacking section are orientated horizontally. An independent claim is included for a method for the stacking of products by the proposed device.

Description

The invention relates to a device for forming stacks of flat products, in particular of paper products, and a method for stacking products according to the preamble of claims 1 and 14, respectively.

A device of this kind is for example from the WO-A-02/22482 known. In the apparatus described therein, paper products coming from a high-speed printer are fed in a continuous stream along a feed direction to a transfer section and deposited on a horizontally oriented, rigid delivery table. The tray table is lowered vertically during the stacking process and filled with paper products until the stack has the required number of paper products. Then there is a vertical lowering of the tray table to a transfer section. In the transfer section, a belt conveyor passes through the lattice-like storage table and transports the stack of paper products away. The now empty tray table is moved back by a further belt conveyor horizontally against the feed direction by more than the length of the tray table and transported by another belt conveyor horizontally upwards to a ready position. As soon as the delivery table is required to receive a new stack, another belt conveyor transports the delivery table horizontally and parallel to the feed direction into the transfer section. For an uninterrupted formation of stacks, at least one further delivery table is guided horizontally and vertically in the cycle-like table circulation in each case.

In the EP-B-0737640 a method and apparatus for introducing an auxiliary stack receiver in a sheet delivery of printing machines is disclosed. In this case, an auxiliary stacking frame is introduced in the sheet running direction and synchronously with the run of a paper product to be deposited on the main stack via a main stack to be removed with continuous supply of other sheets (paper products). Subsequently, the main stack can be removed and subsequently the auxiliary pile receptacle can be pulled out, so that the paper products can be put back on the pallet (storage table) of the main stack. Alternatively, the auxiliary stack picking up the new main stack. In a further removal of the now on the auxiliary stack receiving come to rest, the main pile must then be introduced according to another auxiliary stack recording.

In all known stackers, the extent of the table circulation in the feed direction of the stream of paper products is at least twice the length of a tray table. The case required large size of the device results from the shape of the table circulation, which is composed of straight vertical and horizontal sections. The associated transport of the delivery tables perpendicular to the shelf for the paper products also limits the speed of transfer of the delivery tables in the table circulation.

The present invention has for its object to provide a method and an apparatus of the type mentioned above, which makes it possible to stack products, in particular paper products in a variable number horizontally stacked and stack with little effort and in a small footprint in more quickly provide timing for downstream devices.

This object is achieved by a device having the features of claim 1 and by a method having the features of claim 13.

The inventive device for forming stacks of sheet products, in particular of paper products, paper products are fed in an input stream through a feed conveyor to a transfer section. The device has at least two delivery tables with at least one storage surface each for stacks of supplied products. The tray tables are moved along a loop-like table circulation, an imaginary, extending in the circumferential direction of the connecting line between positions of the center of the surface of the shelf during a circulation cycle, and are at least segmentally flexible. As a result, they are able to adapt to the shape of curvatures of the table circulation at least in segments and at least in subregions. An output stream of stacked paper products is then removed from a transfer section by a removal conveyor.

Due to the flexible, the curvatures of the table turn adapting tray tables, it is possible to construct the table circulation very tight and space-saving and give the entire device a very compact design. At the same time, the tray tables can be guided in a movement with their front side ahead, now, due to a significantly reduced air resistance at the same time more stable transport position, at a higher speed in the table circulation. To this This results in shorter circulation times for the delivery tables.

Preferred embodiments of the inventive method and the inventive device form the subject of the dependent claims.

Fig. 1

in einer perspektivischen Darstellung eine einer Rotationsschneidvorrichtung nachgeordnete Vorrichtung zum Stapeln von Papierprodukten;

Fig. 2

in einer Seitenansicht die in Fig. 1 gezeigte Vorrichtung zum Stapeln von Papierprodukten;

Fig. 2a

in einer abstrahierten Seitenansicht einen Tischumlauf der Ablagetische;

Fig. 3

in einer Frontansicht die in Fig. 1 gezeigte Vorrichtung zum Stapeln von Papierprodukten;

Fig. 4

einen vergrösserten Ausschnitt IV aus der in Fig. 3 gezeigten Vorrichtung in Seitenansicht; und

Fig. 5a-5d

Seitenansichten der in Fig. 1 gezeigte Vorrichtung zum Stapeln von Papierprodukten zu vier verschiedenen Zeitpunkten.

The invention will be explained in more detail with reference to the drawings. It shows purely schematically:

Fig. 1

in a perspective view of a rotary cutting device downstream device for stacking paper products;

Fig. 2

in a side view the in Fig. 1 apparatus for stacking paper products;

Fig. 2a

in an abstracted side view, a table top of the tray tables;

Fig. 3

in a front view the in Fig. 1 apparatus for stacking paper products;

Fig. 4

an enlarged section IV from the in Fig. 3 shown device in side view; and

Fig. 5a-5d

Side views of in Fig. 1 shown apparatus for stacking paper products at four different times.

In the Fig. 1 schematically an apparatus for forming stacks 10 of sheet products, in particular of paper products 12, in one embodiment of a paper stacker 14 is shown. The paper stacker 14 is one Rotary cutting device 16 of known type downstream. The rotary cutter 16 cuts a continuous paper web 18 into individual sheets that form an input stream of paper products 12 and are fed to the paper stacker 14 by an intermediate conveyor 22. The in Fig. 1 shown intermediate conveyor 22 transports the paper products 12 in a feed direction Z to a feed conveyor 28. The feed conveyor 28 takes over the paper products 12 and promotes them to a transfer section 32 on.

After reaching its predetermined storage position 38 on a still empty storage area 40 of the tray table 42 or on an already present on a storage table 42 stack 10 of paper products 12 comes the newly promoted paper product 12 due to gravity to lie. The stack 10, which is raised by each further paper product 12, is successively lowered together with the delivery table 42 in a stacking section 44 in such a way that the upper surface of the highest paper product 12 located on the stack 10 to be charged almost coincides with the original height of the empty delivery surface 40 of FIG Filing table 42 matches. This reduction takes place until the stack 10 has the desired number of superimposed paper products 12. In this case, the tray 10 carrying the stack 10 is then lowered to a lower level of a transfer section 46. The stack 10 is transported out of the transfer section 46 with the delivery table 42 and thereby pushed onto a removal conveyor 48 in the form of a belt conveyor. The removal conveyor 48 mounted on a transfer table 50 further transports the stack 10 to its destination. The circulation-like deflection of the tray tables 42 to reloading with paper products 12 will now be related to Fig. 2 described in detail.

In Fig. 2 is a side view of the inventive paper stacker 14 shown purely schematically. For reasons of clarity, a representation of carrier and housing elements of the paper stacker 14 has been dispensed with. As already mentioned in connection with the overview in Fig. 1 mentioned, the paper products 12 are first brought by a feed conveyor 28 at a feed rate of about 50 m / min to about 150 m / min to the transfer section 32. The sheet-like paper products 12 assume a substantially horizontal position and are guided with their front edge edge 52 ahead. This ensures a stable transport position with low air resistance and high Zufördergeschwindigkeit for the paper products 12. The feeder 28 shown may alternatively be replaced by other embodiments of conveyors, for example a belt conveyor. The Zufördergeschwindigkeit can be adapted to individual needs, especially the leading transport, cutting or printing devices.

The roller pairs 30 of the feed conveyor 28 are driven by a toothed belt drive 54 by an associated electric motor 56. The electric motor 56 can be controlled electrically in such a way that the paper products 12 are accelerated or braked in the feed direction Z and thus the feed rate of the paper products 12 is influenced, for example, as a function of a lowering speed of the tray tables 42 or a feed speed of the tray tables 42 into the takeover section 32.

For the collection of the paper products 12 in the transfer section 32, these are taken over by the belt conveyor 58 from the feed conveyor 28 and transported to its storage position 38. The paper products 12 can be actively braked by the belt conveyor 58 and / or stopped passively by an end stop 60 in its storage position 38. In the embodiment shown, both measures are used to ensure a precise storage position 38 with gentle treatment of the leading front side edge 52 of the paper products 12. The belt conveyor 58 has four, mutually parallel, pulley-studded axles 62.1, 62.2, 62.3, 62.4. The end faces of the axes 62.1, 62.2, 62.3, 62.4 form a rectangular arrangement. The belt conveyor 58 is driven by an associated electric motor 64 via the axle 62.1.

Alternatively, the paper products 12 from the belt conveyor may also continue to be in Fig. 2 shown additional unit 66, for example, a conveyor further transported.

The storage tables 42 are moved in a table circulation 68, an imaginary, running in a direction of rotation U connecting line between positions of the area center of a storage surface 40 during a circulation cycle. The table circulation 68 is in Fig. 2 and Fig. 2a represented by a dashed line and runs parallel to the display plane. The storage tables 42 are segmentally flexible and thus able to adapt in their shape curvatures of the table circulation 68 segment by segment and at least in some areas.

The flexibility of the tray tables 42 is sign and direction dependent, so that on the one hand only positive Curvatures of the tray tables 42 around the table circulation 68 for in relation to the table circulation 68 convexly curved storage surfaces 40 are possible and on the other hand curvatures of the rotating storage tables 42 occur only in planes that are parallel to the plane in which the table circulation 68 runs.

Perpendicular to the plane of the table circulation 68, the delivery tables 42 are rigid in their circulation. In this way, they receive sufficient stability to support a stack 10 of paper products 12 with a lateral supportive storage. The feature of the directional flexibility of the tray tables 42 is achieved by an assembly of slats rigid along their longitudinal axes, which are pivotable in the assembly against each other with respect to their longitudinal axes. Alternatively, storage tables 42 are also conceivable with the ability to adapt to positive and negative curvatures around the table circulation 68.

In addition, for the in Fig. 2 and Fig. 2a shown table circulation 68, an arrangement possible in which the table circulation 68 is rotated for example by 90 ° relative to the feed direction Z and thus perpendicular to the plane of representation in Fig. 2 runs.

As in particular in the abstracted side view in Fig. 2a 2, after the transfer section 32, the stack section 44 and the transfer section 46, the counter circulating table 68 comprises, as viewed counterclockwise, a return section 72, a desk storage 74 and a provision section 76. The functions of the sections 32, 44, 46, 72, 74 , 76 of the table circulation 68 are described in detail in connection with the FIGS. 5a-5d described.

The lowering of the horizontally oriented delivery table 42 in the stacking section 44, which extends from the transfer section 32 to the transfer section 46, is effected on both sides laterally engaging side supports 80 on rotating table support belts 82. A detailed description of the cooperating elements is in connection with Fig. 4 ,

In the transfer section 46, the movement of the tray tables 42, as in Fig. 2 shown in a nearly parallel to the feed direction Z extending discharge direction A. The tray table 42 is by a cam bar 84 which is stretched on a roller chain pair 86 between a driving sprocket 88.1 and four driven sprockets 88.2, 88.3, 88.4, 88.5 and radially from Roller chain pair 86 protrudes outwards, pushed forward. The cam bar 84 presses during its circulation against the trailing, seen in the direction of rotation U rear end face 89 of the tray table 42 and moves it thereby in the direction of rotation U forward. The axes of the sprockets 88.1, 88.2, 88.3, 88.4, 88.5 are parallel to each other and with respect to their end faces, as in Fig. 2 shown arranged in nearly a rectangle spanning manner. The cam bar 84 performs for each removal of a tray table 42 with the roller chain pair 86 a complete circulation, which is monitored by a sensor 90.

The powered by a further electric motor 92, driving sprocket 88.1 accelerates the roller chain pair 86 in terms of the gentlest possible treatment of the stack gently with an acceleration less than 2 m / s ² . This is achieved by a ramp-type electrical control of the electric motor 92. The assumed after the acceleration phase end speed of the roller chain pair 86 is variably adjustable. In order to allow a greater acceleration of the tray table 42, it is conceivable to bring the stack 10 and the tray table 42 simultaneously with the cam bar 84 into abutment and to accelerate.

The tray table 42 meets in the direction of rotation U with its leading in this direction front side 94 on a comb-like guide grid 96. The guide grid 96 has T-shaped, parallel to each other in the discharge direction A aligned grid elements 98 to horizontally tapering on their filing tables 42 vertically downwards in the Reject return portion 72 and thus cause a curvature 99 in the table circulation 68. In Fig. 2 only one outer grid element 98 is visible. The storage tables 42 come after their right angle rejection, which they are able to adapt due to their flexibility, initially on a vertically oriented guide rail 100 to the plant. The guide rail 100 extends for a further curvature 102 against the discharge direction A, slightly inclined horizontally downwards and thereby initiates the delivery tables 42 with its front side 94 in front of the return section 72 in the table storage 74 a.

While the tray tables 42 are deflected downwards by the guide grid 96, the stack 10, guided on horizontally aligned upper edges 104 of the grid elements 98, moves further in the discharge direction A. The guide grid 96 thus separates the stream of temporary im Paper stacker 14 jointly managed paper products 12 and tray tables 42 again in separate streams.

The stack 10, as soon as it projects beyond the guide grid 96 in the discharge direction A, is supported by the removal conveyor 48 and guided by it to its destination. The removal of the stack 10 is monitored by means of a mounted on the guide grid 96 further sensor 106. The speed of the removal belt is variable and is preferably between 2 m / min and 20 m / min.

The table memory 74 can accommodate a variable number of tray tables 42, such as five tray tables 42, interposing and releasing them sequentially for another cycle. The storage tables 42 come to lie in the table storage 74 horizontally one above the other. A further roller chain pair 108 revolving below the table storage 74 is equipped with a further cam strip 110 projecting from the roller chain pair 108. The roller chain pair 108 runs parallel to the delivery tables 42 between a driving further sprocket 112.1 and two driven further sprockets 112.2, 112.3, whose axes are aligned parallel to each other. The driving sprocket 112.1 is driven by a further electric motor 114. To remove a storage table 42 from the table storage 74, the cam bar 110 presses against the rear end face 89 of the delivery table 42 and thereby moves it forward in the direction of rotation U. It is in each case the first introduced into the table memory 74 storage table 42 also released first for another round.

In the direction of rotation U follows after the Table store 74, the staging portion 76 with a further curvature 116, which leads to the adapting tray table in a vertical upward direction. For this purpose, the cam strip 110 pushes the delivery table 42 with its front side 94 first, initially to the level of a further sensor 118, and from there on until the delivery table 42 is taken over by a table supply drive 120. In the provision section 76, the storage surfaces 40 are guided substantially at right angles to their position in the stacking section 44, which allows a slight expansion of the table circulation 68 in the feed direction Z and thus a very compact design of the paper stacker 14.

The Tischbereitstellungsantrieb 120 has a between a driving gear 122.1 and a driven wheel 122.2 encircling, toothed on both sides toothed belt 124. The timing belt 124 acts on the top of the tray tables 42 on both sides in the lateral, in Fig. 4 shown edge structures 126.1, 126.2 formed engagement structures 128 together such that the teeth of the toothed belt 124 engage in elevations and depressions of the edge regions 126.1, 126.2.

It is conceivable both on the top and / or the bottom of the tray tables 42 engagement structures 128, with which corresponding timing belt drives can cooperate. Optionally, a movement of the delivery tables 42 by friction on a drive belt or a drive wheel is possible.

The toothed belt 124 (or possible drive belt) are in lateral positive guides in the form of U-shaped further guide rails 100 against the moving Tray tables 42 pressed.

The entire supply section 76 is equipped with such guide rails 100, which are made of plastic in the embodiment shown.

For the provision in the transfer section 32, the delivery tables 42 are first moved over a further curvature 130 of the guide rails 100 first by the Tischbereitstellungsantrieb 120 in the direction of rotation U and then from a lower run 132 of another toothed belt 134 of a horizontally oriented Tischeinzuges 136 almost jerk and shock-free up in their storage position 38 transported. In this case, in turn, the circulating toothed belt 134 cooperates with the engagement structure 128 formed on both sides in the edge regions 126.1, 126.2 on the upper side of the deposition table 42 and moves the deposition table 42 forward. The typical duration for the process of feeding a tray table 42 through the table feeder 136 is 0.4 s to 0.8 s.

In the transfer section 32, both-sided guide rail sections 138 are designed to be unlockable. For this purpose, there is a linkage 140 with two switching arms 142.1, 142.2 above the transfer section 32, wherein a centrally disposed suspension 144 of the linkage 140 is vertically displaceable by means of a lifting magnet, not shown. In an upper position of the suspension 144 engage, as in Fig. 4 shown for the end of the left switching arm 142.1, guide claws 146 in laterally formed on the tray tables 42, rectangular in cross-section retaining grooves 148 a. The retaining grooves 148 form the guide rail portions 32 for the tray tables 42. In a vertical displacement Down the suspension 144, the guide claws 146 are folded outwardly out of the retaining grooves 148. As a result, the tray tables are exposed on the side brackets 80 of both sides arranged table carrying straps 82 and can have a in Fig. 3 shown stepper motor 150, which is connected via right and left-hand worm drives with drive wheels 152.1, 152.2 of the table carrying straps 82 are lowered.

The arranged on both sides and rotating in opposite directions table support straps 82 are each equipped with chains 154.1, 154.2, where the side brackets 80 are resiliently mounted. The side supports 80, which extend over the entire side length of an overlying tray table 42, have a cross-section which forms almost a right-angled triangle. At the overhead on lowering side 156 of the side brackets 80, on which the tray table 42 comes to rest, vertically upstanding edges 158 are formed horizontally laterally, instead of the guide rails 100, limit the position of the tray tables 42.

In Fig. 5a - 5d are side views of the in Fig. 1 to Fig. 4 illustrated paper stacker 14 shown at four different times. In contrast to the previous illustrations, only the four delivery tables 42.1, 42.2, 42.3, 42.4 are simultaneously in the table circulation 68. In each case, six stacked paper products 12 form a complete stack 10.

Fig. 5a shows the paper stacker 14 when depositing another paper product 12 on an existing but still incomplete stack 10 in the transfer section 32. The stack 10 carrying tray table 42.1 is already in the lowered state in the stack section 44. Below, also in the stack section 44 is the, loaded with a complete stack 10 tray table 42.2. Below the storage table 42.2 is already in the transfer section 46 of the table 42.3. On the removal conveyor 48, a complete stack 10 is shown, which has previously been transported from the delivery table 42.4 to the transfer section 46. The storage table 42.4 has already passed through the return section 72 and is located in the table storage 74.

In a next, in Fig. 5b In the phase shown, the delivery table 42.4 has left the table storage 74 again and is already in the provision section 76. The delivery table 42.1 located in the stacking section 44 has been lowered again and the stack 10 carried by it already has another paper product 12 brought to the deposit. To the same extent as the storage table 42.1, the storage table 42.2 has also been lowered. The delivery table 42.3 is deflected at the guide grid 96 into the return section 72, while the stack 10 carried by it is pushed further horizontally onto the removal conveyor 48 in the discharge direction A.

The storage table 42.3 has to in Fig. 5c already left the return section 72 and is located in the table memory 74. The in the previous phase still in the provision section 76 located tray table 42.4 has now been detected by table supply drive 120. The storage table 42.1 has already received the number of six paper products 12 and is in the stacking section 44 has already been lowered deeper than is provided for receiving a further paper product 12. The removal conveyor 48 has the in Fig. 5b still completely taken on the tray table 42.3 stack 10 and transported him off.

The in Fig. 5d State shown illustrates a time very shortly after in Fig. 5c shown. In this case, the storage table 42.4 has already been partially displaced by the table supply drive 120 into the transfer section 32 and has been grasped by the table feeder 136. Within a short time, the storage table 42.4 is now released by the folding away of the guide claws 146, not shown, for storage on the likewise not shown side brackets 80 of the table support straps 82 and is available for receiving a further stack 10. The storage tables 44.1, 44.2 located in the stacking section 44 have been lowered only slightly further down, the storage table 44.3 is still in the table storage 74.

The positions of the tray tables 42 in the table circulation 68 are determined at any time by an electronic control device, not shown. In response to input signals generated in particular by the sensors 90, 96 118 in the paper stacker 14, by upstream or downstream devices, such as the rotary cutter 16, optional additional units 66, such as a conveyor, and / or by an operator generates the control means control and output signals for the electric motors 56, 64, 92, 114, 150 of the paper stacker 14, upstream and downstream devices, optional additional units 66 and / or the operator.

Claims (13)

1. Device for forming stacks (10) of sheet-like products, in particular of paper products (12), having at least two set-down tables (42) which have at least one set-down surface (40) in each case for stacks (10) of supplied products and which are moved along a table-circulating system (68) in a circuit-like manner in a circulating direction (U), an imaginary connecting section running in said circulating direction (U) between positions of the surface central point of the set-down surface (40) during a circulating cycle, wherein the table-circulating system (68) has a transfer section (32), to which the products (12) which are to be stacked are supplied in an input stream by a feed conveyor (28), a stacking section (44) which is connected downstream of the transfer section (32) in the circulating direction (U) and in which stacks (10) are formed from the supplied products (12) on the set-down surface (40) of the set-down tables (42), and a delivery section (46) which is connected downstream of the stacking section (44) in the circulating direction (U) and in which the finished stacks (10) are removed from the set-down tables (42) by a removal conveyor (48), characterized in that the set-down tables (42) are flexible at least in some segments and, as a result, are capable of adapting their shape to curvatures (99, 102, 116, 130) of the table-circulating system (68), at least in some segments and at least in subregions of the table-circulating system (68), and in that the table-circulating system (68) has a table store (74) which is connected downstream of the delivery section (46) in the circulating direction (U) and is used for the temporary storage of set-down tables (42).
2. Device according to Claim 1, characterized in that in the stacking section (44) the table-circulating system (68) runs virtually rectilinearly between the transfer section (32) and the delivery section (46), and the set-down tables (42) are guided at least in a virtually horizontal orientation in the stacking section (44).
3. Device according to Claim 2, characterized in that in the stacking section (44) the set-down tables (42) are mounted by laterally engaging side mounts (80) on circulating table-carrying bands (82) with an opposed direction of circulation, and are lowered.
4. Device according to one of Claims 1 to 3, characterized in that in the region of the delivery section (46) the table-circulating system (68) is curved in the circulating direction (U) from an at least virtually horizontal course to form an at least virtually vertical course, and in that the set-down tables (42), as they pass through this curvature (99), push the stacks (10) at least virtually horizontally onto a comb-like guide grid (96) which preferably engages in the set-down tables (42).
5. Device according to one of Claims 1 to 4, characterized in that in the region upstream of the delivery section (46) the table-circulating system (68) is curved in the circulating direction (U) from an at least virtually vertical course to form an at least virtually horizontal course.
6. Device according to one of Claims 1 to 5, characterized in that the number n of set-down tables (42) in the table-circulating system (68) and the number of set-down tables (42) moved in the table-circulating system (68) is variable and is preferably at maximum seven set-down tables (42) (n_max = 7).
7. Device according to one of Claims 1 to 6, characterized in that the set-down tables (42) are equipped, for their guidance along the table-circulating system (68), with an engagement structure (128) which is used for the engagement of guiding means, in particular of a toothed belt (124).
8. Device according to one of Claims 1 to 7, characterized in that the set-down tables (42) are guided, for their guidance along the table-circulating system (68), in lateral edge regions (126.1, 126.2) in U-shaped guide rails (100).
9. Device according to Claim 8, characterized in that the engagement structure (128) is formed at least in one edge region (126.1, 126.2), preferably in two opposite, parallel edge regions (126.1, 126.2) of the set-down table (42).
10. Device according to one of Claims 7 to 9, characterized in that the engagement structure (128) is designed in the form of elevations and/or depressions on the set-down table (42), and in that a toothed belt (124) engages as guiding means in the engagement structure (128).
11. Device according to one of Claims 1 to 10, characterized in that the spatial and temporal distance of the set-down tables (42) and therefore their position in the table-circulating system (68) is determined by a control device, preferably an electronic control device.
12. Device according to Claim 11, characterized in that the control device is influenced by devices connected upstream or downstream, in particular by a rotational cutting device (16) or a printer, or by additional units (66), in particular a continuing conveyor.
13. Method for operating the device according to one of Claims 1 to 12, characterized in that the set-down tables (42) are moved by curvatures (99, 102, 116, 130) of the table-circulating system (68), to which curvatures the set-down tables (42) are adapted at least in some segments and at least in subregions and in that the set-down tables (42) are moved into the table store (74) and, after temporary storage, are moved out of the table store (74) again.

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