DEVICE AND METHOD FOR BUFFERING A PLURALITY OF GOODS OR GROUPS OF GOODS AND PAPER HANDLING SYSTEM COMPRISING SAME

Abstract

A device for buffering a plurality of goods or groups of goods includes a buffer section configured to receive a plurality of goods or groups of goods. In addition, a buffer transport is provided, configured to move a good or group of goods at a buffer transport speed. A runout is configured to move out a good or group of goods from the device at a runout speed which is higher than the buffer transport speed. The runout is additionally configured to take over transport of a good or group of goods before the good or group of goods has reached an end of the buffer section.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of copending International Application No. PCT/EP2011/068354, filed Oct. 20, 2011, which is incorporated herein by reference in its entirety, and additionally claims priority from German Application No. 10 2010 043 063.3, filed Oct. 28, 2010, which is also incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

Embodiments of the invention relate to processing goods or groups of goods, in particular to processing sheets which are processed within a paper handling system as individual sheets or groups of sheets.

Paper handling systems exemplarily serve for producing letters being sent to a plurality of recipients, using which telephone bills, bank statements or similar things are, for example, sent. Cover notes of this kind either include an individual sheet or a plurality of sheets which are then processed within the system as a group. The sheets processed by the system are then exemplarily introduced into an envelope by means of an inserter and sent to a recipient. In such paper handling systems, the sheets forming the plurality of cover letters are fed via one or several input channels, collecting the sheets of a group of sheets being necessitated before processing same together. The sheets may exemplarily be provided by a paper roll onto which the plurality of sheets have been printed before, exemplarily in a multi-up manner. The roll is then fed via the input channel and at first cut in a longitudinal and a transverse direction so as to generate individual sheets which are subsequently collected in a collection stage as individual sheets or groups of sheets. The speed at which the sheets of a collecting stage can be provided may differ depending on the speed at which same are moved out of the collection stage for being provided to subsequent processing, such as, for example, a folding mechanism.

FIG. 1 shows a paper handling system including a plurality of handling stages, i.e. a cutter 100, a so-called merger 102, a collecting stage 104 and a folding mechanism 106, schematically. At an input, the cutter 100 receives a paper web 108 which is imprinted with the text of the individual sheets 110 and 112 to be generated later on in a several-up manner. In the upper section, FIG. 1 shows a schematic top view illustration of the processed sheets and, in the lower part, a schematic side view illustration of the sheets. The cutter 100 causes a longitudinal cut and a transverse cut of the paper web 108 so as to separate the individual sheets 110 and 112, such that, as is shown in FIG. 1, after cutting, there are single sheets. From the cutter 100, the individual sheets 110 and 112 are transferred in parallel to the merger 102, or merging web, which moves both sheets 110 and 112 such that they are arranged one above the other, as is shown in FIG. 1. The sheets arranged in this way are transferred from the merger 102 to the collecting stage 104. As has been mentioned, the folding mechanism 106 follows the collecting stage 104. In order to decouple the speed at which the sheets are received from the collecting stage 104 from the speed at which the folding mechanism 106 can process sheets, a buffer 114 (illustrated by a buffer section 114) is arranged between the output of the collecting stage 104 and the input of the folding mechanism 106, a plurality of individual sheets or groups of sheets 116a to 116I being arranged in the buffer, for example in a shingled arrangement, as is shown in FIG. 1. The collecting stage 104 is configured to deposit the received sheets 110, 112 at a first buffer stage along the buffer section 114 of the buffer. At the end of the buffer section 114, the group of sheets, or individual sheet 1161, present at the last buffer position is withdrawn at a speed corresponding to a processing speed of the following component, in this case the folding mechanism. The group of sheets 118 withdrawn is fed to the folding mechanism, exemplarily a double folding mechanism, and the folded groups 118′ are fed to further processing. Further processing may either be sealing, for example, the short sides of the folded group of sheets 118′ such that the mail piece to be sent is finished here already. In this case, at least one of the individual sheets 110, 112 is printed such that an addressee is visible on the outside after the folding process. Alternatively, the folded group of sheets 118′ may be fed to an inserter which subsequently inserts the group of sheets 118′ into envelopes.

Providing the buffer section 114 allows decoupling the processing speeds of the components arranged in front of the collection stage 104 from the processing speed of the components arranged after the collecting stage 104. This means that the input channel formed by the cutter and the merger 102 may operate at a basically constant speed, since the speed excess relative to the processing speed of the folding mechanism 106 is compensated by the buffer section 114. Conventional buffer sections 114 operate such that an individual sheet or group of sheets is deposited at the first buffer stage 116a and passes each individual buffer stage 116a-116I in correspondence with the speed of a buffer transport provided, irrespective of the filling state of the buffer section 114. When the group reaches the output of the buffer section 114, it is withdrawn.

The arrangement of a buffer is not limited to the configuration of a paper handling system as shown in FIG. 1. Basically, such a buffer is employed wherever decoupling of speeds is necessitated, such as, for example, where a preceding component provides a good or a group of goods at a speed which may be higher than a speed at which a subsequent component is able to accept the good or group of goods. FIG. 1a shows further examples of the arrangement of one or several buffers in a paper handling system, wherein a buffer may be arranged at all positions or only at selected positions shown in FIG. 1a. A buffer 114 may generally be arranged between the input channel and an inserter 120. In the input channel of the paper handling system, a buffer 114 may be arranged between the merger 102 and the collecting stage 104 (not shown in FIG. 1a) and/or between the collecting stage 104 and the folding mechanism 106 and/or between the folding mechanism 106 and a merging web 122 and/or between the merging web 122 and the inserter 120. In addition, a buffer 114 may be arranged between the inserter 120 and a post-processing component, such as, for example, a postage module 124.

Different approaches for realizing a buffer within a paper handling system are known from conventional technology. EP 1 206 402 A and EP 1 206 407 A describe buffers which receive a plurality of sheets or groups of sheets in a shingled manner, and, in particular, approaches for accepting sheets or groups of sheets into such a buffer stage in a shingled manner, or withdrawing sheets of a group from such a buffer stage. EP 1 433 733 A describes a buffer transport system for an inserting system in which each buffer stage is formed by several pairs of rolls including associated sensorics so as to optionally provide a four-stage or six-stage buffer, depending on the format to be processed. EP 1 108 668 A describes a temporary storage for documents wherein continuous transport is provided for by belts by means of which documents taken over from a preceding component are moved through the buffer. A movable slide is provided for establishing a buffer section within the system. WO 2004/063071 A describes a buffer for receiving a stack of sheets wherein the sheets are deposited in a shingled manner and the entire stack is moved to the output for withdrawing a sheet so as to be able to withdraw a lower sheet from the stack.

EP 1 433 733 A relates to a flexible buffer transport system for buffering collected documents, the buffer being formed by a plurality of rolls and sensors which may each be controlled individually by special motors. Depending on the format to be processed, buffer positions are established using the controller and corresponding rolls are associated to the individual buffer positions and driven together. In a case in which there are no downstream documents within the buffer transport for a collected group, transfer of the collected documents to the transport of the following inserter takes place synchronously and depending on the availability of the transport of the following envelope. When there are one or several empty buffer positions in the direction towards the output, the buffer section in accordance with EP 1 433 733 A avoids passing all the buffer stages in correspondence with the buffer transport speed by moving on at the speed of the following component, however, the setup and control in accordance with EP 1 433 733 A are complicated with regard to both mechanics and controlling. In addition, this known buffer section does not allow a shingled arrangement of goods or groups of goods.

SUMMARY

Departing from this known technology, it is the object of the present invention to develop a buffer such that moving the group of goods or good out quickly is made possible such that unnecessary queue times, as may be found in the known technology in accordance with FIG. 1, are avoided without complicating the setup in terms of mechanics and controlling.

According to an embodiment, a device for buffering a plurality of individual sheets or groups of sheets may have: a buffer section configured to receive a plurality of individual sheets or groups of sheets; a buffer transport configured to move an individual sheet or group of sheets at a buffer transport speed; and a runout configured to move out an individual sheet or group of sheets from the device at a runout speed which is higher than the buffer transport speed; characterized in that the runout is configured to act on an individual sheet or group of sheets at a last occupied position along the buffer section so as to take over transport of the individual sheet or the group of sheets before the individual sheet or group of sheets has reached an end of the buffer section.

According to another embodiment, a paper handling system may have: one or several handling stages; and at least one device as mentioned above for collecting individual sheets or groups of sheets.

According to still another embodiment, a method for buffering a plurality of individual sheet or groups of sheets in a buffer section for receiving a plurality of individual sheet or groups of sheets, a buffer transport moving an individual sheet or group of sheets at a buffer transport speed, and a runout moving out an individual sheet or group of sheets at a runout speed which is higher than the buffer transport speed, may be characterized by the following step: acting, by the runout for moving out, on an individual sheet or group of sheets at a last occupied position along the buffer section so as to take over transport of the individual sheet or the group of sheets before the individual sheet or group of sheets has reached an end of the buffer section.

In accordance with embodiments of the invention, the buffer section includes a plurality of successive buffer positions, each buffer position being configured to receive a good or group of goods. The buffer positions along the buffer section are set fixedly or are settable variably in dependence on a dimension (such as, for example, length) of the good to be buffered or group of goods to be buffered.

In accordance with embodiments of the invention, a novel buffer device is suggested, in which, unlike in conventional buffers, a good or group of goods does no longer have to pass all the buffer positions in a buffer in correspondence with a buffer transport speed until finally withdrawal for further transport to a following component is achieved. In accordance with embodiments of the invention, this is achieved by the fact that each buffer position within the buffer device may still be occupied by a good or group of goods, however, in case that buffer positions remain unoccupied before the runout, a kind of “moveable” runout is provided which allows withdrawal of a good or group of goods from the last occupied buffer position without the good or group of goods having to pass each individual following empty buffer stage in correspondence with the clocked driving of the buffer transport. Exemplarily, when forming groups, the runout is moved to the last occupied buffer position to cause direct withdrawal for subsequent processing there, wherein this last buffer position is closer to the output of the buffer device with several successive small groups and closer to the input of the buffer device with several successive larger groups. However, a situation in which every subsequent buffer position is passed using the buffer transport is avoided, rather a finished collected group is withdrawn directly from the last occupied buffer position for subsequent processing. In accordance with embodiments of the invention, this is realized by a movable runout which is moved to the last occupied buffer position so as to accept a good or group of goods there. Alternatively, providing selectively connectable runout elements of the runout at predetermined discrete points may be provided, exemplarily a runout element may be provided at each buffer position such that, in case a central buffer position is the last occupied buffer position, the runout element associated to this buffer position and also all other runout elements associated to the subsequent empty buffer positions are lowered so as to allow contact to the good to be moved out so as to allow accelerated move out, irrespective of the buffer transport of the buffer device.

The known technology mentioned above in accordance with EP 1 433 733 A is based on an approach in which the concept of separating buffer transport and runout transport is abandoned and instead a plurality of individually driven pairs of rolls are used which allow the functionality of the buffer transport on the one hand and the functionality of the runout transport on the other hand by corresponding controlling. In accordance with embodiments of the invention, in contrast, the basic concept of a buffer as has been described referring to FIG. 1 is maintained, i.e. a concept which provides for providing buffer transport and runout transport, wherein the buffer transport moves the good from one buffer stage to the next within the buffer and the runout transport passes the good on to a subsequent component. The approach in accordance with embodiments of the invention provides modification of this conventional buffer approach in that the runout which so far has been arranged statically at the end of the buffer section is configured to be “moveable” and thus goods are moved out from a last occupied buffer position.

In contrast to conventional approaches, the device in accordance with embodiments of the invention is of advantage finished collected goods/groups of goods may now be moved out rapidly since it is no longer necessary to pass the entire buffer section from one buffer position to the next in accordance with the buffer transport speed. In contrast to known technology, as is known from EP 1 433 733 A, the approach in accordance with an embodiment of the invention is of advantage since the functionality of the buffer device and corresponding elements, i.e. in-feed, buffer section and runout, is maintained in principle, whereas in accordance with the document cited a complete modification of the conventional buffer device is necessitated. In accordance with embodiments of the invention, the control complexity is smaller since the basic controlling of the buffer section essentially remains unchanged and only corresponding control of the moveable runout is necessitated in order to cause early withdrawal of a group or individual good from a last occupied buffer position along the buffer section. In contrast to known technology, as is known from EP 1 433 733 A, the approach in accordance with embodiments of the invention is of further advantage since the goods or groups of goods may be accepted in the buffer section in a shingled or non-shingled manner.

In accordance with embodiments of the invention, the buffer may be part of a collection stage which will then be able to collect and buffer at the same time a plurality of goods or groups of goods.

In accordance with further embodiments of the invention, the buffer transport includes a first vacuum transport comprising a plurality of vacuum chambers which may be activated selectively, and the runout includes a second vacuum transport comprising a plurality of vacuum chambers which may be activated selectively, wherein one or several of the activated vacuum chambers of the first vacuum transport may be provided so as to define a position for receiving the good or group of goods. The first and second vacuum transports may be arranged next to each other or above each other.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will be detailed subsequently referring to the appended drawings, in which:

FIG. 1 is a schematic illustration of a paper handling system including a plurality of handling stages, including a conventional buffer section;

FIG. 1a shows further examples of the arrangement of one or several buffers in a paper handling system;

FIG. 2 is a schematic illustration of a buffer stage in accordance with an embodiment of the invention comprising a plurality of actuatable runout modules along the buffer section;

FIG. 3 is a schematic illustration of the buffer stage of FIG. 2 in accordance with another embodiment of the invention;

FIG. 4 is a schematic illustration of the buffer stage of FIG. 2 in accordance with still another embodiment of the invention;

FIG. 5 is a schematic illustration of a buffer stage in accordance with an embodiment of the invention comprising a runout module moveable along the buffer section;

FIG. 6 is a side sectional illustration of the moveable runout in accordance with FIG. 5 in accordance with an embodiment of the invention;

FIG. 7 is a top view sectional illustration of the runout of FIG. 6 along the line b-b in FIG. 6;

FIG. 8 shows an embodiment of an in-feed mechanism in accordance with embodiments of the invention;

FIG. 9 shows a guiding rail pair of the in-feed mechanism of FIG. 8 in accordance with an embodiment; and

FIG. 10 is a schematic illustration of a buffer stage in accordance with another embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Same elements or elements having the same effect are provided with the same reference numerals in the following description of embodiments of the invention.

An embodiment of the invention will be discussed below referring to FIG. 2, wherein the runout is formed by a plurality of runout modules. FIG. 2 shows a schematic illustration of the buffer stage 200 comprising an in-feed 202 for feeding the sheets to a buffer section 204 including a plurality of transport units 206a-206f, the transport units 206a-206f being arranged at corresponding buffer positions 207a-207f of the buffer 200 and being moveable between same. Each of the transport units 206a-206f includes a clamping element 208, such as, for example, one or several pairs of pliers 208 of which only the pair of pliers 208 arranged at the transport unit 206a is shown in FIG. 2. The pliers 208 serve for clamping a good arranged at a transport unit 206, such as, for example, an individual sheet or a group of sheets, such that same may be moved through the buffer. The transport units 206a-206f are, for example, arranged along a buffer transport 209, such as, for example, along a conveyer belt or along a conveyer chain, spaced apart from one another, wherein the conveyer chain is driven by a drive not shown in FIG. 2 in a clocked manner (in start/stop operation) so as to move the transport units through the buffer section 204 in correspondence with a predetermined buffer transport speed, such that exemplarily the first transport unit 206a shown in FIG. 2 has passed buffer positions 206a-e after five clocks and reached buffer position 206f where the buffer position 206f is arranged in FIG. 2. In the example shown in FIG. 2, for reasons of simplicity, only an individual sheet 210 which is received by the first transport unit 206a arranged at the first buffer position 207a is arranged in the buffer section 204. More precisely, the, in the direction of transport, back end of the sheet 210 is held at the first transport unit 206a by the clamp 208. The remaining buffer positions along the buffer section 204 are unoccupied. If sheets were arranged here, too, a plurality of groups of sheets or individual sheets would be arranged within the buffer section 204 in a shingled manner, similarly to what is shown in FIG. 1.

Additionally, the buffer stage 200 includes a runout 212 which in the embodiment shown is formed by a plurality of runout modules 212a-e. Each of the runout modules 212a-212e includes a carrier 214a-214e provided so as to carry a conveyer element 216a-216e. The conveyer element 216a-216e may be formed by a roll, two or several rolls arranged one after the other in the direction of transport of the good or group of goods, a belt or a roll of a D-shaped cross-section. In the embodiment shown in FIG. 2, the runout modules 212a-212e are arranged so as to be moveable vertically, as is shown by corresponding arrows 213 in FIG. 2. Each of the runout modules 212a-212e is associated to one of the buffer positions 207b-207f downstream of the in-feed 202. The first buffer position 207a which is opposite the in-feed 202 has no runout module associated therewith. The clocked mode of driving the buffer section 204 is such that, during a movement clock, a transport unit (such as, for example, 206b) is advanced by a section from a buffer position (such as, for example, 207b) to the next buffer position (such as, for example, 207c) such that a runout module will be “opposite” a transport unit.

The runout modules 212a-212e may be controlled individually so as to be moved vertically between a first position and a second position. In the first position, the runout module 212 is arranged such that the associated conveyer element 216a does not engage the individual sheet or group of sheets arranged within the buffer, as is exemplarily shown in FIG. 2 using the runout modules 212a-212c which are arranged in their first positions. In the second position, the runout modules, see, for example, runout modules 212d and 212e, are arranged such that their conveyer elements 216 engage a good to be transported so as to allow transport of the good irrespective of the transport speed of the buffer transport 209.

As has been mentioned, in the embodiment illustrated in FIG. 2 only a single sheet 210 is exemplarily arranged along the buffer section 204. Groups of sheets, folded goods or goods inserted in envelopes may also be buffered instead of an individual sheet. Same has been deposited at the first buffer position 207a by the in-feed 202 and received by the transport unit 206a present there at that time and held for transport along the buffer section. Thus, the following buffer positions 206b-206e are free or unoccupied. In accordance with conventional approaches, the transport unit 206a would have to be moved along the buffer section 204 in a clocked manner by means of the buffer transport until an, in the direction of transport, front end of the sheet 210 has reached a stationary runout arranged at the end of the buffer section where it is accepted by same and removed. When exemplarily assuming that the position of the stationary runout corresponded to the position of the runout module 212e, in the embodiment of FIG. 2, at least one clock would be necessitated for moving the sheet 210 on, only then could removal take place. In accordance with embodiments of the invention, however, early removal is allowed by finding out that the buffer positions 207b-207f are unoccupied such that a runout module 214d associated to the front end of the sheet 210 and a following runout module 212e are lowered to the second position so as to allow engagement of the sheet 250. This causes removal of the individual sheet 210 in the direction of the output of the buffer section by the runout module 212d in cooperation with the runout module 214e at a speed independent of buffer transport such that the sheet 210 is able to leave the buffer section 204 early without at first having to wait until it has reached the runout by means of the buffer transport.

In the embodiment illustrated in FIG. 2, the buffer additionally includes a sensor circuit configured to detect a position of a good or group of goods along the buffer section 204. The sensor circuit includes a plurality of sensors S which are illustrated schematically in FIG. 2, at least one sensor S each being associated to one of the buffer positions 207a-f so as to determine whether a buffer position is occupied or unoccupied. The runout 212 is configured to determine, based on the sensor signals, the buffer position along the buffer section 204 where the transport of a good or group of goods is to be taken over by the runout 212 in the manner described before. Alternatively, a position of a good or group of goods in the buffer may be calculated without requiring sensors which detect a position of the good along the buffer section. Calculation may then take place based on a speed at which the drives of the buffer operate or at which the good or group of goods is moved and based on a known format size of a good or the largest good in a group which may, for example, be provided by the job description. The speed of the drives or speed of the good or group of goods may exemplarily be detected by suitable sensors.

It is to be pointed out here that, using FIG. 2, an embodiment has been described in which the sheets or groups of sheets are arranged within the buffer section 204 in a shingled manner and are held by the transport unit at a, in the direction of transport, back end. In this case, the sheets or groups of sheets are “pushed” along the buffer section. Alternatively, the sheets or groups of sheets may also be held by the transport unit in a, in the direction of transport, front end. In this case, the sheets or groups of sheets are “pulled” along the buffer section. However, the invention is not limited to buffers which receive the goods or groups of goods to be buffered in a shingled manner. Also, a non-shingled arrangement may be provided for such that, for example, one compartment each for receiving a sheet or group of sheets is formed by two transport elements arranged on the buffer transport in a spaced-apart manner. The spacing of the transport elements exemplarily corresponds to a format length of the sheets to be processed. Depending on the circumstances, a corresponding arrangement of the sheets in a shingled manner or non-shingled manner may be desirable.

The buffer transport 209 may be the pliers transport shown in FIG. 2. Other transport mechanisms may also be used, such as, for example, a stud transport which includes individual compartments for receiving the good or group of goods. The pliers or studs of the buffer transport 209 are in fixed distances to one another, corresponding to the distance of the buffer positions 207.

As can be seen from FIG. 2, the original approach of separating runout and buffer transports is maintained by the buffer transport 209 and the runout 212 each including separate transport elements. The buffer transport 209 may include pliers transport or stud transport and the runout 212 may include roll or belt transport.

Another embodiment of the invention wherein the runout 212 includes a plurality of runout modules, similarly to FIG. 2, is shown referring to FIG. 3. In the embodiment shown in FIG. 3, the runout modules 212a-212e which are opposite the corresponding buffer positions 207a-207f or associated thereto, are provided again. Additionally, for bridging the distance between two successive buffer positions, further runout modules 218a-218e which are equal in setup to the modules 212a-212e and are also moveable in correspondence therewith between the first and second positions are provided. Each of the runout modules shown in FIG. 3 includes a carrier which in the module 212a is exemplarily referenced by the reference numeral 214a. The carrier 214a carries the conveyer element 216a which is mounted to be rotatable around an axis 224a so as to allow rotation in the direction of the transport direction. The additional runout modules 218a-218e also include carriers 220e and conveyer elements 222e which are mounted to be rotatable around an axis 226e. In the runout modules in accordance with FIG. 3, the axes 224 and 226 are moveable vertically, as is illustrated by the arrow 227 so as to cause lowering of the conveyer elements 216 and 222, respectively, from the first position in which there is no engagement of the goods, to the second position, where engagement of the goods is possible.

In the example shown in FIG. 3, the buffer section 204 contains three sheets or groups of sheets 210, 210′ and 210″, wherein the group 210 is, for example, held by the transport unit 206c and the group 210′ by the transport unit 206b. Group 210″ is about to be introduced into the buffer section and is to be received and held by the transport unit 206a. Similarly to FIG. 2, in FIG. 3, too, it is to be recognized that there are no further groups arranged in the direction of transport after group 210 such that group 210 is moved out already before reaching the end of the buffer section 214 in correspondence with the teachings in accordance with embodiments of the invention by moving the runout modules 212d and 212e and the runout modules 218c-218e from the first position to the second position so as to ensure engagement of the good between the last occupied buffer position and the runout or output of the buffer section. The conveyer elements of the runout modules mentioned are driven at the necessitated removal speed which is higher than the transport speed of the buffer section such that the group of sheets 210 or individual sheet 210 is moved out rapidly.

FIG. 4 shows another embodiment which is similar to the embodiment in accordance with FIG. 3. In the embodiment shown in FIG. 4, the runout modules are implemented such that no vertical movement thereof is necessary between the first position and the second position. Rather, the conveyer elements 216 and 222 of the corresponding runout modules are implemented by rolls having a D-shaped cross-section, so-called D-rolls which are arranged in the module 212a to be rotatable around the corresponding rotational axis 224 and 226, respectively, in the direction of the arrow 229 shown in FIG. 4. The conveyer elements 216, 222 at the beginning are in a rest position, as is exemplarily shown in the module 212a where there is no engagement of the goods. For causing transport of the goods, the conveyer element is rotated, as is shown in the runout module 212d so as to move same to a second position or through a second position so as to cause engagement of the sheet 210 to cause same to be conveyed. The runout modules following the module 212d are driven in a staggered manner so as to cause temporally adjusted actuation of the corresponding conveyer elements 222 and 216 to cause the sheet 210 conveyed by the module 212d to be conveyed further in the direction of the output.

Another embodiment of the invention will be described below referred to FIG. 5. In FIG. 5, buffer 200 is shown again, wherein, unlike in the embodiment shown in FIGS. 2-4, the runout 212 is realized by a single runout module 230 which is movable along the direction of transport, as is illustrated in FIG. 5 by the arrow 231. The setup of the inlet and the buffer section corresponds to the setup in accordance with FIG. 2 and, similarly to FIG. 2, only an individual sheet 210 or group which is arranged along the buffer section 204 is illustrated for reasons of simplicity. Similarly to FIG. 2, in FIG. 5, too, the buffer is empty after sheet 210 such that it would be necessitated for reaching a fixed runout at the end of the buffer section to move the sheet 210 through the buffer positions 206b to 207f in a clocked manner in correspondence with the transport speed of the buffer transport until the, in the direction of transport, front end of the sheet 210 has reached the stationary runout. Similarly to FIGS. 2 to 4, this is avoided in the embodiment shown in FIG. 5 by allowing early withdrawal of the sheet 210 when there are no further sheets, in the direction of transport in front of the sheet, in the buffer section. In the embodiment shown in FIG. 5, the runout 212 includes the moveable module 230 which includes a carrier 232 and a conveyer element 234 mounted to the carrier 232 which may be implemented in the same manner as in the modules described before using FIGS. 2 and 3. The moveable module 230 is arranged such that its conveyer element 234 will be able, in every position, to engage a sheet or group of sheets 210, if there are any along the buffer section. When recognizing that sheet 210 is the last sheet, the movable module 230 is moved, departing from a rest position, which is exemplarily arranged at the end of the buffer section, in the direction of the buffer input until the front end of the sheet 210 which in the example shown in FIG. 5 is at the buffer position 207e has been reached, wherein subsequently the sheet 210 is removed at a removal speed which is higher than a transport speed of the buffer transport. For removal, it may be provided for that the module 230 moves in the direction of the output during conveyance of the sheet by the conveyer element 234 so as to ensure continuous conveying of the sheet.

An embodiment of the invention for realizing the moveable runout 212 in accordance with

FIG. 5 will be discussed in greater detail below referring to FIGS. 6 and 7. FIG. 6 shows a side sectional illustration of the runout and FIG. 7 shows a top view sectional illustration. In FIG. 6, the buffer section 204 is shown comprising the buffer positions 207a to 207k where the transport units 206a-206k which are moved between the buffer positions in a clocked manner in the conventional manner using a buffer transport are arranged. Exemplarily, the buffer transport 209 includes a chain circulating around two rolls such that the transport units are moved back to the beginning of the buffer section when reaching the end of the buffer section. In the embodiment shown in FIG. 6, sheets or groups of sheets 210, 210′ and 210″ are shown in the buffer section, the group of sheets 210 being held by the transport unit 206b at the buffer position 207b and the group of sheets 210′ being held by the transport unit 206a at the buffer position 207a, as can be recognized by the clamping mechanism 208 folded back. The group of sheets 210 is held either by another buffer position not shown in FIG. 6 or has already been introduced so as to be received by a transport unit engaging the group of sheets 210′ in the next clock.

The runout 212 includes a top belt transport 236 and a bottom belt transport 238. The top belt transport 236 includes a first return roll 240 and a second return roll 242 for guiding a top transport belt 244. The top belt transport additionally includes the moveable runout module 230 which is arranged to be moveable along the direction of transport of the goods 210, as is illustrated by the arrow 231. The sled 230 includes a carrier structure 232 where the conveyer element 234 is arranged so as to allow rotational movement. In addition, the carrier structure 232 carries two return rolls 246 and 248 which are arranged one behind the other in a spaced-apart manner in the direction of transport. The transport belt of the top belt transport 236 is received by the return rolls such that the first return roll 246 receives the belt 244 at a position spaced apart from the buffer transport 204. The belt 244 extends between the two return rolls 246 and 248 such that the second return roll 248 guides the belt at a lower portion neighboring to the buffer section 204. The first roll 240 of the top belt transport 236 has greater a diameter than the second roll 242 such that the belt is guided between the second return roll 248 and the first roll 240 of the belt transport 236 neighboring to the buffer transport 240 such that the belt engages a good or group of goods as is shown in FIG. 6 at the reference numeral 250 so as to cause removal thereof at a removal speed which is higher than the buffer transport speed. The transport belt 244 is, in a portion between the second roll 242 of the belt transport 236 and the front return roll 246 of the sled 230, guided in a manner spaced apart from the buffer section 204 such that same does not engage one or several goods arranged on the buffer section.

The conveyer element 234 is a roll element having a D-shaped cross-section (D roll) which is actuated when reaching a desired withdrawal position of the sled so as to catch a sheet at the position, exemplarily sheet 210 at the position 206j, or the, in the direction of transport, front edge thereof and introduce same by a rotation between the belt 240 of the top belt transport and a belt 252 of the bottom belt transport 238 so as to allow removal at the withdrawal speed. The bottom belt transport also includes two rolls 254 and 256 over which the bottom belt 252 is guided. By the cooperation of the two belts 252 and 244 in the portion behind the sled 230 in the direction of transport, withdrawal of the sheets or groups of sheets introduced in this region is allowed at the desired removal speed.

Depending on which of the positions 207 shown in FIG. 6 is the last occupied position, i.e. the last position where there is a good, the sled 230 is moved to a suitable withdrawal position, exemplarily to a position corresponding to the front end of the sheet held by a transport unit. When reaching the withdrawal position, the conveyer element 234 is actuated so as to move between the belts 244 and 252 and remove the object at the removal position, exemplarily the sheet or group of sheets.

FIG. 7 shows a top view illustration of the arrangement of FIG. 6 cut in a direction perpendicular to the plane of the sheet along the line b-b. In FIG. 7, the belt 244 redirected by the second return roll 248 can be made out, as are the return rolls 240 and 242 of the top belt transport 236. Additionally, it can be recognized that the sled 230 comprises a carry bar 258 arranged transverse to the direction of movement where two conveyer elements 234a and 234b are arranged movably so as to cause transfer of a good to be removed in the region between the belts 244 and 252 in the manner described above. Additionally, guide elements 260a and 260b which engage corresponding guiding rails 262a and 262b are provided at the carry bar 258 so as to allow moving the sled back and forth along the direction of transport between the desired withdrawal positions. The guiding rails 262a and 262b are exemplarily mounted to the casing 264 of the arrangement, which is shown in FIGS. 6 and 7. Elements 266a and 266b are stops which are arranged at the guiding rails 262a and 262b so as to limit movement of the sled 230. In addition, in FIG. 7, the sheets or groups of sheets 210, 210′, 210″ are illustrated deposited in a shingled manner. Additionally, group 250 to be moved out at the moment is shown.

An embodiment in which the runout transport includes the withdrawal roll and the belt transport has been described in FIGS. 5 and 6. Different embodiments may include alternative transport elements. In accordance with an embodiment, the runout may include a gripping element, such as, for example, a pair of pliers, which is arranged at the moveable module and takes up and holds the good to be removed such that the good is moved in the direction of the buffer output by the movement of the module.

The buffers described using FIGS. 2 to 7 allow a filling speed and an emptying speed of the buffer which are principally independent from each other.

In the embodiments described before, it has been explained that the goods or groups of goods are arranged in a shingled manner, however, the invention is not limited to such a kind of buffering. Rather, compartments for taking up goods or groups of goods in a non-shingled manner may also be provided in the buffer.

An embodiment of an in-feed mechanism in accordance with embodiments of the invention will be described below making reference to FIGS. 8 and 9.

FIG. 8 shows a lateral illustration of the in-feed 280. The in-feed 280 includes the guiding element 290 which comprises two compartments 300 and 302 (see FIG. 9) which extend along the buffer section 204 in the direction of transport. The compartments 300 and 302 serve for taking up one or several sheets received from a preceding component. The compartments 300 and 302 may be controllable such that, when actuating same, either both sheets within the arrangement 290 are deposited on the buffer section 204 and exemplarily, taken up and then clamped by the guiding element 206a at the, in the direction of transport, back end of the sheets. Alternatively, the compartments 300 and 302 may be actuated such that only the group in the bottom compartment 302 is released and the group 300 in the top compartment is transferred to the bottom compartment. In FIG. 8, a drive roll for the buffer transport 209 by means of which the individual buffer elements 206 are moved in a clocked manner along the different buffer positions is schematically shown with the reference numeral 310.

FIG. 9 shows an illustration of an embodiment of the device 290 of FIG. 8. The guiding element 290 includes two guiding rails 312a, 312b which are arranged by a distance d transverse to the direction of transport. The guiding rails 312a and 312b are implemented each to define the chambers 300a, 300b and 302a, 302b for receiving the sheets 296 and 298, respectively. The guiding rails 312a and 312b are rotatable in the direction of the arrows shown in FIG. 9. In addition, a common transport element 314 which causes transport of both the bottom sheet 296 and the top sheet 298 is provided. As is shown in FIG. 9, a first pair of chambers 302a, 302b is arranged at a bottom position neighboring to the first buffer position and a second pair of chambers 300a, 300b is arranged at a top position neighboring to the first buffer position.

The mode of functioning of the in-feed described using FIG. 9 will be discussed in greater detail below. We assume that the sheets are provided by an arrangement, as is shown using FIG. 1. The merged goods are taken over together from the merger by the center drive 314 and the top and bottom sheets are taken over laterally from the merger in the separate guiding rails such that the sheets are further introduced into the collection stage. The sheets arrived in the collection stage are deposited downwards onto the buffer by a rotation by 180° of the lateral guidings 312a and 312b. The rotation by an angle of, for example, 180° has the effect that both goods 296, 298 from both pairs of chambers 300a,b, 302a,b are deposited at the first buffer position. When the group has been composed, the buffer is advanced by a corresponding distance predetermined by the clock such that exemplarily the transport unit 206a arranged at the position 207a shown in FIG. 8 is advanced by a position, namely to the position 207b. Here, the groups may be clamped by the pliers 208 at back left and right sides. The runout releases clamping so as to let the group continue, exemplarily to the folding mechanism. Forming groups takes place at the clocking performance of the cutting machine, the runout following in correspondance with the buffer.

With small groups, the buffer is filled quicker than emptied. In accordance with embodiments of the invention, the runout travels in the direction of the folding mechanism, together with the buffer. With larger groups, the runout proceeds in the direction of the collecting stage and empties the buffer continuously. An intelligent controller provides for the buffer to be filled in correspondence with the collecting amount. When the buffer reaches its filling limit, the speed of the previous component has, of course, to be reduced.

The runout may pass on groups with a small distance between goods, thereby allowing a folding mechanism, for example, to be used optimally, wherein at the same time the transport speed of the folding mechanism may be reduced.

With unpaired goods, i.e. when receiving two sheets 296 and 298 which belong to different groups to be collected, the lateral guidings are rotated only by 90°. The bottom sheet is placed with its group on the buffer, the top sheet is given from the top to the bottom guiding rail. A maximum of two sheets are collected in the bottom guiding rail. When being transported to the buffer, the sheets are deposited by the lateral guidings such that no additional vibration is necessary. Thus, rotation of the guidings by an angle of, for example, 90° causes the good 296 contained in the first pair of chambers 302a, 302b to be deposited at the first buffer position and the first pair of chambers 302a, 302b to be moved from the bottom position (exemplarily to the top position). At the same time, the second pair of chambers 300a, 300b with the good (298) contained therein is moved to the bottom position.

It is pointed out here that more than two pairs of chambers which may be moved through different positions by a suitable mechanism may also be provided such that one or several of the chambers are discharged at the first buffer position, depending on the movement.

Instead of the in-feed described using FIGS. 8 and 9, other implementations of the in-feed may also be used, exemplarily an in-feed may comprise a transport mechanism for transferring a good or a group of goods from a preceding component to the first buffer position by means of a roll or belt transport, wherein the feeding transport, for example, essentially is in the plane of the buffer section.

FIG. 10 shows a buffer section in accordance with another embodiment of the invention. In contrast to the embodiments described so far in which belts or roll transports have been used, a vacuum transport is used in the buffer section in accordance with FIG. 10.

The buffer section 400 shown in FIG. 10 includes an in-feed 402 and a runout 404. The buffer section includes a top transport 406 and a bottom transport 408 between which a group or group of goods is moved. At the in-feed 402, both the top transport 406 and the bottom transport 408 include an in-feed roll 410a, 410b between which a good or group of goods introduced into the buffer section 400 is conveyed. In addition, the top transport 406 includes a top vacuum transport 412 including a belt 412a guided over two rolls 412b and 412c. Furthermore, the top vacuum transport 412 includes a plurality of vacuum chambers 412d. The bottom transport 408 includes a bottom vacuum transport 414 which, similarly to the top vacuum transport 412, comprises a belt 414a guided around two rolls 414b and 414c. Additionally, the bottom transport includes a plurality of vacuum chambers 414d. The vacuum transports 412 and 414 each include selectively controllable vacuum chambers 412d and 414d, respectively, wherein transport of a good or group of goods may take place by transporting only at those positions along the belt where the associated vacuum chambers are provided with a vacuum. In FIG. 10, the vacuum chambers of the top transport 412 and the bottom transport 414 characterized by an “x” are inactive, i.e. despite a movement of the corresponding belts 412a and 414a, no good or group of goods is conveyed at these positions.

In the embodiment shown in FIG. 10, the buffer section 400 includes the bottom and top drives or transports 412 and 414 just described which may each be controlled separately from each other. More precisely, the respective drives each include separately controllable vacuum chambers, wherein the number of vacuum chambers is not limited to that shown in FIG. 10, rather more or less vacuum chambers may be provided as long as there is more than one vacuum chamber in each transport. In accordance with embodiments, controlling the vacuum chambers is done via a multi-channel valve.

The functionality of the buffer section 400 described using FIG. 10 is such that the top transport 406 is responsible for accepting a good or group of goods from the in-feed 402 and for transporting the good or group of goods along the buffer section. The individual goods or group of goods are introduced into the buffer section 400 at the in-feed speed. The vacuum chambers 412d of the top transport are activated up to the good running out, which means that all the goods or groups of goods, except for the good running out, are held by the top transport/drive and transported in the direction of the runout 404 in a particular transport speed. Thus, a plurality of positions where a good or a group of goods may be received is defined by the top activated vacuum chambers 412d, wherein in the example shown in FIG. 10 the respective positions are defined fixedly or variably. In accordance with the embodiment of FIG. 10, it may be provided for each of the vacuum chambers 412d to define a position or buffer position and for this definition to be predetermined fixedly. Alternatively, however, it may also be provided for to control two or several vacuum chambers 412d together and thus to set a number of positions along the buffer section 400 variably, wherein the same number of vacuum chambers 412d does not necessarily have to be united to form one position, but also different numbers of vacuum chambers may define a position. In the example shown in FIG. 10, the activated vacuum chambers 412d of the top transport 412 are referred to by 1 to 11. These vacuum chambers are passed when a good or group of goods is introduced. The last activated vacuum chamber in the example shown in FIG. 10 is the vacuum chamber referred to by 11. The following vacuum chambers referred to by the “x” are not required, i.e. the buffer is not filled completely. When introducing another good into the buffer, the vacuum chamber following vacuum chamber 11 is activated such that the movement of the belt causes transport of the goods such that a new good to be taken up is conveyed by the vacuum chamber 1.

The bottom transport 408 is responsible for the good or group of goods to be output. In order to cause moving out of a group of goods or a good, the vacuum chambers 414d of the bottom transport necessitated for this, in this case the five vacuum chambers to the right, are activated. FIG. 10 shows a good running out at 416 which is moved in the direction of the runout 414 by the bottom transport 414. The bottom vacuum transport 414 runs at higher a speed than the buffer transport, wherein this speed may equal that of the runout transport.

The top and bottom vacuum chambers 412d and 414d are controlled synchronously in correspondence with the position and length of the good running out. The arrow 418 in FIG. 10 shows the borderline of the active and inactive vacuum chambers 412d, which follows the position of the good to be output. As has already been mentioned above, the buffer is filled quicker with smaller groups than with larger groups such that, when taking up smaller groups, the last occupied buffer position travels in the direction of the runout 404, whereas with larger groups the last occupied position travels in the direction of the in-feed 402, as is indicated by the arrow 418. The vacuum chambers 412d are activated/deactivated correspondingly.

An embodiment in which the transports 412 and 414 are arranged one above the other is shown in FIG. 10, however, the present invention is not limited to this. In accordance with other embodiments of the invention, the transports 412 and 414 are arranged in the same level, the functionality described above remaining the same.

Although some aspects have been described in connection with a device, it is to be understood that these aspects also represent a description of a corresponding method such that a block or element of a device is also to be interpreted to be a corresponding method step or characteristic of a method step. In analogy, aspects having been described in connection with a method step or as a method step, also represent a description of a corresponding block or detail or characteristic of a corresponding device.

While this invention has been described in terms of several embodiments, there are alterations, permutations, and equivalents which will be apparent to others skilled in the art and which fall within the scope of this invention. It should also be noted that there are many alternative ways of implementing the methods and compositions of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention.

Claims

1. A device for buffering a plurality of individual sheets or groups of sheets, comprising:

a buffer section configured to receive a plurality of individual sheets or groups of sheets;

a buffer transport configured to move an individual sheet or group of sheets at a buffer transport speed; and

a runout configured to move out an individual sheet or group of sheets from the device at a runout speed which is higher than the buffer transport speed;

wherein

the runout is configured to act on an individual sheet or group of sheets at a last occupied position along the buffer section so as to take over transport of the individual sheet or the group of sheets before the individual sheet or group of sheets has reached an end of the buffer section.

2. The device in accordance with claim 1, comprising a sensor circuit configured to detect a position of an individual sheet or group of sheets along the buffer section.

3. The device in accordance with claim 2, wherein the buffer section comprises a plurality of successive buffer positions, each buffer position being configured to receive an individual sheet or group of sheets, and wherein the sensor circuit comprises a plurality of sensors, at least one sensor each being associated to a buffer position so as to determine whether the buffer position is occupied or unoccupied,

wherein the runout is configured to determine, based on the sensor signals, the buffer position along the buffer section where the runout takes over transport of an individual sheet or group of sheets.

4. The device in accordance with claim 1, wherein the buffer transport comprises pliers transport or stud transport, wherein the pliers or studs of the buffer transport comprise fixed distances to one another in correspondence with the distance of buffer positions along the buffer section.

5. The device in accordance with claim 1, wherein the buffer transport and the runout each comprise different transport elements.

6. The device in accordance with claim 5, wherein the buffer transport comprises a pliers transport or stud transport, and wherein the runout comprises a roll or belt transport.

7. The device in accordance with claim 1, wherein the buffer section comprises a plurality of successive buffer positions, each buffer position being configured to receive an individual sheet or group of sheets, and wherein the runout comprises a plurality of runout modules, a runout module each being associated to a plurality of buffer positions starting from a last buffer position along the buffer section, each module being actuatable selectively for engaging a buffered individual sheet/buffered group of sheets at a buffer position, and the runout modules between an output of the device and the last occupied buffer position along the buffer section being actuated so as to move out an individual sheet or group of sheets from this device.

8. The device in accordance with claim 7, wherein each of the plurality of runout modules comprises a conveyer element, the conveyer element being arranged to be displaced between a first position and a second position, the conveyer element in the first position not engaging an individual sheet or group of sheets, and the conveyer element in the second position engaging an individual sheet or group of sheets.

9. The device in accordance with claim 7, wherein each of the plurality of runout modules comprises a conveyer element arranged at a fixed position, the conveyer element being implemented to be rotated between a first position and a second position when being actuated, the conveyer element in the first position not engaging an individual sheet or group of sheets, and the conveyer element in the second position engaging an individual sheet or group of sheets.

10. The device in accordance with claim 1, wherein the buffer section comprises a plurality of successive buffer positions, each buffer position being configured to receive an individual sheet or group of sheets, and wherein the runout comprises a moveable runout module configured to be moved to the last occupied buffer position along the buffer section for taking over transport of the sheet or group of sheets comprised therein.

11. The device in accordance with claim 10, comprising:

a belt transport comprising a belt extending from an inlet of the buffer section to an outlet of the buffer section,

wherein the moveable runout module comprises: a conveyer element moveable between a first position and a second position, the conveyer element in the first position not engaging an individual sheet or group of sheets, and the conveyer element in the second position engaging an individual sheet or group of sheets; and a pair of rolls receiving the belt of the belt transport such that the belt does not engage the individual sheet or group of sheets in front of the moveable runout module in the direction of transport of the individual sheet or group of sheets and engages an individual sheet or group of sheets after the moveable runout module in the direction of transport, wherein the conveyer element is operative to engage an individual sheet or group of sheets using the belt of the belt transport.

12. The device in accordance with claim 11, wherein the conveyer element is arranged for being shifted or rotated between the first position and the second position.

13. The device in accordance with claim 8, wherein the conveyer element comprises a roll, two or more rolls arranged one behind the other in the direction of transport of the individual sheet or group of sheets, a belt or a roll comprising a D-shaped cross-section.

14. The device in accordance with claim 1, comprising:

an in-feed configured to feed an individual sheet or group of sheets to the buffer section,

wherein the in-feed comprises a drive for transporting an individual sheet or group of sheets, and a pair of lateral guidings,

wherein each of the lateral guidings comprises at least two chambers which define pairs of chambers for receiving each at least one sheet, a first pair of chambers being arranged at a bottom position neighboring to the buffer section, and a second pair of chambers being arranged at a top position spaced apart from the buffer section,

wherein the guidings are arranged rotatably and are controllable so as to cause rotation by a first angle or by a second angle,

wherein the rotation by the first angle causes both goods from both pairs of chambers to be fed to the buffer section, and

wherein a rotation by the second angle causes the sheet comprised in the first pair of chambers to be fed to the buffer section and the first pair of chambers to be moved from the bottom position, and the second pair of chambers, with the sheet comprised therein, to be moved to the bottom position.

15. The device in accordance with claim 1, wherein:

the buffer transport comprises a first vacuum transport comprising a plurality of selectively activatable vacuum chambers, and

the runout comprises a second vacuum transport comprising a plurality of selectively activatable vacuum chambers.

16. The device in accordance with claim 15, wherein receiving of the individual sheet or group of sheets is caused by one or several of the activated vacuum chambers of the first vacuum transport.

17. The device in accordance with claim 15, wherein the first and second vacuum transports are arranged next to each other or above each other.

18. The device in accordance with claim 1, wherein the buffer section is configured to receive the sheets or group of sheets in a shingled or non-shingled manner.

19. A paper handling system comprising:

one or several handling stages; and

at least one device for buffering a plurality of individual sheets or groups of sheets, comprising: a buffer section configured to receive a plurality of individual sheets or groups of sheets; a buffer transport configured to move an individual sheet or group of sheets at a buffer transport speed; and a runout configured to move out an individual sheet or group of sheets from the device at a runout speed which is higher than the buffer transport speed; wherein the runout is configured to act on an individual sheet or group of sheets at a last occupied position along the buffer section so as to take over transport of the individual sheet or the group of sheets before the individual sheet or group of sheets has reached an end of the buffer section for collecting individual sheets or groups of sheets.

20. The paper handling system in accordance with claim 19, wherein the handling stages comprise a cutter, a merger and a folding mechanism,

wherein the device for collecting the individual sheets or groups of sheets is arranged between the merger and the folding mechanism.

21. A method for buffering a plurality of individual sheet or groups of sheets in a buffer section for receiving a plurality of individual sheet or groups of sheets, a buffer transport moving an individual sheet or group of sheets at a buffer transport speed, and a runout moving out an individual sheet or group of sheets at a runout speed which is higher than the buffer transport speed;

comprising:

acting, by the runout for moving out, on an individual sheet or group of sheets at a last occupied position along the buffer section so as to take over transport of the individual sheet or the group of sheets before the individual sheet or group of sheets has reached an end of the buffer section.