WO2025252610A1

WO2025252610A1 - Processing system and method for processing a reel

Info

Publication number: WO2025252610A1
Application number: PCT/EP2025/065021
Authority: WO
Inventors: Yvan WIRZ
Original assignee: SICPA Holding SA
Current assignee: SICPA Holding SA
Priority date: 2024-06-03
Filing date: 2025-05-30
Publication date: 2025-12-11
Anticipated expiration: 2026-12-03

Abstract

Processing system (1) comprising a reel unwinding unit (5); a cutting unit (6); a first conveyor belt (7); a second conveyor belt (8); a stacking unit (9); a quality control unit (10); and an ejection unit (11).

Description

PROCESSING SYSTEM AND METHOD FOR PROCESSING A REEL

TECHNICAL FIELD

The present invention relates to the technical field of processing a reel comprising adjacent security documents into a stack of individual security documents. In detail, the present invention relates to a processing system for processing a reel comprising adjacent security documents into a stack of individual security documents, and to a method for processing a reel comprising adjacent security documents into a stack of individual security documents.

BACKGROUND ART

In the production of security documents (such as tax stamps, banknotes, checks or the like), it is common to produce sheets comprising multiple security documents (typically arranged in an array) at once. The sheets then need to be cut in order to obtain individual security documents. Sheets are often piled up to cut a pile of sheets in one cut. However, this process involves multiple timeconsuming steps as the sheets need to be piled up, cut, and rearranged into stacks. Cutting a pile of many sheets (for example more than 150 sheets) can result in inaccurate cutting (in particular due to stacks having irregular heights due to inks causing extra thicknesses in some areas) and hence quality issues in the final security documents, while cutting piles of less sheets is time consuming.

It is also known to use an alternative format for processing security documents. Namely, the security documents can be produced and provided in a reel, which is then unrolled and passed through a cutting system to obtain individual security documents. In this case, a challenge is the transport, quality control and stacking of the individual security documents. It is thus desired to provide an improved solution for transporting the individually cut security documents, sorting them according to their quality and providing stacks of security documents having a high quality. The purpose of the present invention is to improve the processing of a reel comprising adjacent security documents into a stack of individual security documents.

SUMMARY OF THE INVENTION

According to a first aspect, a processing system for processing a reel comprising adjacent security documents into a stack of individual security documents is provided. The processing system comprises: a reel unwinding unit; a cutting unit; a first conveyor belt; a second conveyor belt; a stacking unit; a quality control unit; and an ejection unit; wherein the reel unwinding unit is configured to unwind the reel and to feed the adjacent security documents into the cutting unit; the cutting unit is configured to cut the reel between the adjacent security documents to obtain individual security documents; the first conveyor belt is arranged downstream of the cutting unit and is configured to convey the individual security documents on a topside of the first conveyor belt, the first conveyor belt being configured to convey the individual security documents from the cutting unit to a second conveyor belt; the second conveyor belt is realized as a vacuum conveyor belt including a suction device provided on an underside of the second conveyor belt for sucking up the individual security documents conveyed on the topside of the first conveyor belt, the second conveyor belt being configured to convey the individual security documents sucked up from the first conveyor belt towards the stacking unit on the underside of the second conveyor belt; the quality control unit includes a camera for taking images of the individual security documents, and a quality determination unit for determining, based on the image taken of each individual security document, whether the individual security document complies with predetermined quality criteria; the ejection unit is provided along the second conveyor belt and has two states being a neutral state and an ejection state, whether in the neutral state, the ejection unit does not act on the individual security documents conveyed to the stacking unit by the second conveyor belt, and in the ejection state which is triggered by the quality control unit determining that one of the individual security documents does not comply with the predetermined quality criteria, the ejection unit ejects the individual security document which does not comply with the predetermined quality criteria from the underside of the second conveyor belt towards the bottom (in a correct mounting orientation of the processing system); and the stacking unit is provided such that it at least partially faces the underside of the second conveyor belt and is configured to stack the individual security documents arriving on the underside of the conveyor belt which were not ejected by the ejection unit.

The ejection unit allows selectively ejecting the security documents which do not comply with the predetermined quality criteria, so that the stacked security documents all have a satisfactory quality (in accordance with the predetermined quality criteria). The security documents are ejected towards the bottom by the ejection unit, thereby making use of gravity for the ejection process and accordingly facilitating the ejection process as no additional means for displacing the security documents to be ejected are needed. The stacking by the stacking unit may equally rely on gravity for displacing the security documents from the second conveyor belt to the stacking unit, in particular without requiring additional means for displacing the security documents from the second conveyor belt to the stacking unit. The processing system advantageously requires only two conveyor belts, while in particular allowing monitoring the quality of both faces of the security documents. The processing system allows for a fully automated processing and stacking of the security documents.

The security documents can be any type of documents that are used in the context of authentication and/or other security applications. Examples for security documents in particular include tax stamps or other stamps (i.e. labels) for authenticating a product to which they are attached, banknotes, checks, or the like. Security documents usually comprise security features (for example including color shifting motifs, invisible patterns, and/or codes encoding information) which are difficultly reproducible and/or allow to authenticate the security document. Each security document can be unique, for example by including a uniquely defined serial number and/or a uniquely defined code, such as a QR code or other two-dimensional code.

The reel of security documents can be a cylindrical roll on which multiple adjacent security documents are wound. The adjacent security documents can be formed by printing or otherwise depositing inks, engraving, stamping or the like a flexible band/stripe of substrate, which is wound into the reel. The substrate may be a paper and/or any type of synthetic substrate including plastic or polymer substrates. Adjacent security documents here means that the security documents are all provided side by side on a same stripe of substrate. In order to use the security documents, the reel should be cut between the adjacent security documents to obtain individual security documents.

The processing system is in particular provided in an industrial context, more specifically in a production site producing security documents and/or in a packaging site in which the security documents are stacked and packaged.

The reel unwinding unit may be formed by a pair of wheels between which the adjacent security documents pass, at least one of the wheels being driven by an engine for unrolling (i.e. unwinding) the reel. The reel unwinding unit can be arranged upstream and/or downstream of the cutting unit. The terms “upstream” and “downstream” herein respectively refer to a direction of travel of the security documents through the processing system, with upstream designating a direction towards the reel and downstream designating a direction towards the stacking unit.

The cutting unit can be made of any type of device configured to cut the reel. For example, the cutting unit includes one wheel or two wheels facing each other and each having a rotating knife for cutting the reel between the security documents. The cutting unit can also be realized as a guillotine or a laser cutter, for example. The cutting unit can be configured to cut the reel at constant time intervals and/or constant reel unwinding distances (assuming that the unwinding speed and the size of each security document is constant). Alternatively, the cutting unit may be coupled to a trigger sensor with a camera, which detects a predefined feature (such as a mark, letter or so) on each security document and accordingly triggers the cutting unit to cut the reel at a corresponding position. This latter solution accounts for a higher accuracy in the cutting between the adjacent security documents.

The cutting unit cuts between the adjacent security documents such that individual security documents (i.e. security documents separated from one another) are obtained. Since the cutting unit cuts only one security document at a time, a reliability of the cut quality can be improved (as compared to cutting a pile of documents at a time). The first conveyor belt is preferably arranged such that individual security documents exiting the cutting unit are directly conveyed onto the first conveyor belt, i.e. without any additional conveyor belt or robot arm in between. Optionally, only a part of the reel unwinding unit is located between the cutting unit and the first conveyor belt.

The first conveyor belt forms a transport system for the individual security documents. The first conveyor belt can be realized as a vacuum conveyor belt which includes small holes therein, through which an air flow (suction) can maintain the security documents on the first conveyor belt. This suction mechanism allows maintaining the security documents in place, in particular at high moving speeds of the first conveyor belt. The topside of the first conveyor belt on which the security documents are conveyed corresponds to the upper part of the first conveyor belt, i.e. the individual security documents lay flat on the first conveyor belt. The first conveyor belt may also include an underside on which no security documents are transported. Usually, a printed side of the individual security documents is facing upwards as the individual security documents are transported by the first conveyor belt, thereby allowing a visual quality control of the individual security documents in that stage of the process. The first conveyor belt may transport the individual security documents in a straight line and/or along a curved path towards the second conveyor belt.

The second conveyor belt may be arranged such that its underside at least partly faces the topside of the first conveyor belt. In the area in which the first and second conveyor belts are facing one another, a transfer of the individual security documents from the first to the second conveyor belt can be performed. The second conveyor belt can be realized as a vacuum conveyor belt which includes small holes therein, through which an air flow (suction) can maintain the security documents on the first conveyor belt. This suction mechanism allows maintaining the security documents in place, in particular at high moving speeds of the second conveyor belt. Having the second conveyor belt transporting the individual security documents on an underside thereof means that the face of the individual security documents that was facing the first conveyor belt is visible during transportation on the second conveyor belt. This can be advantageous if both faces of the individual security documents are printed, as the transport of the second conveyor belt allows a visual quality control of the face of the individual security document that was hidden on the first conveyor belt. Preferably, the transfer of individual security documents from the first to the second conveyor belt is realized entirely by means of the suction device of the second conveyor belt, which sucks the individual security document up from the first conveyor belt onto the second conveyor belt. In the area in which the first and second conveyor belts are facing one another, a suction mechanism of the first conveyor belt may be turned off to facilitate the transfer to the second conveyor belt. Preferably, no additional device (conveyor belt, robot or the like) is required between the first and second conveyor belt to transfer the individual security documents therebetween. The first conveyor belt may transport the individual security documents in a straight line and/or along a curved path towards the stacking unit. Preferably, the processing device includes precisely two conveyor belts (the first and the second conveyor belts).

The camera of the quality control unit can be oriented such as to capture images of the individual security documents after the cutting by the cutting unit, as they travel on the first conveyor belt and/or as they travel on the second conveyor belt, preferably before they reach the ejection unit. Preferably, the camera captures precisely one image per individual security document. The quality determination unit may include a processor for analyzing the image captured by the camera. The image analysis can include an optical character recognition (OCR) process, for example to determine that a serial number or other alpha-numerical characters was correctly printed on the individual security document. The image analysis can further include a verification of printed colors on the individual security document, a measurement of the position of different features of the individual security document, or the like. The image analysis unit may include a QR code decoder. If the printed QR code is successfully decoded, the predetermined quality criteria can be considered as fulfilled. A similar quality assessment can be applied to human readable code read by the OCR algorithm.

The predetermined quality criteria can be a property that is preset, in particular by the manufacturer of the security documents, and stored in the quality determination unit for comparison with observed parameters of the captured images. The predetermined quality criteria can include one or several of the following requirements: (i) that the OCR returns readable characters corresponding to those printed, (ii) that a printed code on the security document is readable and/or decodable, and/or (iii) that the position of these characters, of the cut performed by the cutting unit and/or of other features are within an allowed tolerance (for example less than 0.5 mm) from their target position. In case that images of both faces of each security document are captured (for example using two cameras, capturing respectively an image of the security document transported on the first conveyor belt and of the security document transported on the second conveyor belt), the predetermined quality criteria of said security document can be determined based on an analysis of both captured images, to ensure that the quality of both faces is satisfactory.

The ejection unit is provided along the second conveyor belt such as to directly eject invalid security documents (i.e. those not complying with the predetermined quality criteria) from the second conveyor belt. By default, the ejection unit is in its neutral state (position), in which it does not impact or move the passing security documents. In particular, the ejection unit remains in its neutral state for all individual security documents which are determined as complying with the predetermined quality criteria by the quality control unit (referred to as “valid security documents” in the following). The ejection unit hence does not eject the valid security documents. The ejection unit receives a trigger signal from the quality control unit when an invalid security document is detected, and the ejection unit accordingly ejects the concerned invalid security document by temporarily switching to the ejection state at the timing corresponding to the passage of the invalid security document. The switching between the neutral and ejection state can be realized by an engine moving the concerned mechanical parts of the ejection unit. With the ejection unit being provided on the underside of the second conveyor belt, the ejection is simplified because it can strongly rely on gravity dropping the invalid security document, and does not require a robot arm or other conveyor system for ejecting invalid security documents. The invalid security document is ejected towards the bottom in a correct mounting orientation of the processing system, meaning that when the processing system is correctly used, the underside of the second conveyor belt faces downwards, and the ejected invalid security documents are released downwards, i.e. towards the bottom. As used herein, all terms referring to directions such as “up”, “upwards”, “above”, “down”, “downwards”, or “below” refer to the correct mounting orientation of the processing system.

The stacking unit is preferably provided downstream of the ejection unit, such as to stack only valid security documents (i.e. security documents not ejected by the ejection unit). The stacking unit can be provided underneath the second conveyor belt or such that it at least partially faces the underside of the second conveyor belt. That way, the valid security documents can be released downwards (advantageously making use of gravity) for stacking purposes in the stacking unit. A stack of security documents is preferably a pile of at least 100 security documents, more preferably at least 250. In the stack, the sides of the security documents are preferably aligned, which can be achieved using a stacking unit that has the shape of a frame for alignment of the security documents along some or all sides.

According to an embodiment, the stacking unit comprises a support onto which the individual security documents are stacked from above in the correct mounting orientation of the processing system, the support being configured to gradually be displaced downwards as the individual security documents are stacked such as to maintain a constant distance between the underside of the conveyor belt and the uppermost individual security document of the stack.

The support can include a frame to ensure that the security documents are aligned as they are stacked. Gradually moving down the support is advantageous in that the security documents can be placed onto the support directly from the second conveyor belt, without requiring an additional component to individually move the security documents into a stack. The support is in particular moved down in proportion to the number of security documents already stacked, in order to ensure the constant distance between the underside of the conveyor belt and the uppermost individual security document of the stack (corresponding to a constant distance between the underside of the conveyor belt and the support of the stacking unit). The movement of the support can be performed by a dedicated engine.

According to a further embodiment, the ejection unit is realized as a deactivation unit for temporarily and locally switching off a suction functionality of the suction device when the ejection unit is in the ejection state, thereby releasing the individual security document which does not comply with the predetermined quality criteria from the underside of the second conveyor belt towards the bottom.

In this embodiment, the suction mechanism of the second conveyor belt can be locally switched off in the ejection state, thereby forming the ejection unit. The ejection then corresponds to dropping (releasing) the invalid security document downwards (by means of gravity).

According to a further embodiment, the ejection unit is realized as a gate unit which is a mechanical element that is provided alongside the second conveyor belt without touching the individual security documents when the ejection unit is in the neutral state, and which is configured to be rotated and/or moved when the ejection unit is in the ejection state such as to mechanically interrupt and/or modify a path of the individual security document which does not comply with the predetermined quality criteria and to eject it from the underside of the second conveyor belt towards the bottom.

As an alternative or in addition to the suction mechanism being switched off locally to form the ejection unit, the ejection unit may include the gate unit which forms a mechanical switch which switches between the ejection state in which the invalid security document is ejected, and the neutral state in which the gate unit is set aside and does not modify or affect the trajectory of the security documents. The gate unit in particular ejects the invalid security documents by separating the invalid security document from the second conveyor belt, such that the suction device no longer holds the invalid security document onto the second conveyor belt.

According to a further embodiment, an unwinding speed of the reel unwinding unit is smaller than a speed of the first conveyor belt.

The speed of the first/second conveyor belt refers to a travelling speed of the security documents thereon. The unwinding speed of the reel unwinding unit is the speed at which the reel unwinding unit unwinds the reel. In particular, the speed of the first conveyor belt is at least 1.3, preferably at least 1.5 times faster than the unwinding speed of the reel unwinding unit. This allows distancing the individual security documents on the first conveyor belt, which facilitates their handling. A speed of the second conveyor belt may be identical with the speed of the first conveyor belt, as this facilitates calculations about positions of the invalid security documents for ejection thereof by the ejection unit and the like. However, other speeds of the second conveyor belt are also possible, as long as this is accounted for in the ejection unit calibration.

According to a further embodiment, the stacking unit includes a separator which is configured to be inserted above a finished stack having reached a predetermined height or a predetermined number of individual security documents, wherein the separator is configured to temporarily hold the subsequently arriving individual security documents while the finished stack is being removed. The separator may be a plate or sheet, for example of metal or plastic, which is inserted, for example by a robot, an electrical actuator, a pneumatical actuator, or the like, when the stack is considered as finished (i.e. it has the predetermined height or the predetermined number of individual security documents). The separator can be placed at a fixed distance of the downside of the second conveyor belt such as to hold the valid security documents (the valid security documents arriving subsequently to the stack being finished) arriving while the finished stack is removed (for example for packaging or sticking on a product). The separator can be removed once the finished stack is removed from the support, and the support can resume its standard functionalities. Inserting a separator allows avoiding interrupting the processing of the security documents when the stack is finished, which allows processing a larger number of security documents per unit time. The processing ofthe security documents is thus rendered more efficient.

According to a further embodiment, the processing system comprises several stacking units and a displacement unit, wherein the displacement unit is configured to switch the position of the stacking units such that one of the stacking units is always at least partly facing the underside of the second conveyor belt, the displacement unit being configured to displace a current stacking unit currently at least partly facing the underside of the second conveyor belt when the stack of individual security documents in the current stacking unit reaches a predetermined height or a predetermined number of individual security documents and to replace it by another, empty stacking unit.

In order to avoid interrupting the processing of the security documents, several stacking units can be provided with the displacement unit switching their position so that the stacking units can be used one after another. When one stacking unit is full, it is displaced away by the displacement unit for being emptied and replaced by an empty stacking unit. The stacking units can be provided side by side (for example on a linear rail), so that the displacement unit moves them back and forth. The stacking unit can also be provided in a ring arrangement, so that the displacement unit rotates the ring of stacking units.

According to a further embodiment, the individual security documents are tax stamps, labels or banknotes.

Tax stamps can be stamps or label to be attached to products (such as tobacco, alcohol, valuable goods or the like) and certifying that a specific tax has been paid. The term “labels” generally designates any security document that can be attached to a product and in particular provides a description of the product or manufacturer (for example serial numbers or a two dimensional code encoding specific information), thereby allowing to authenticate the product. According to a further embodiment, the first conveyor belt is realized as a vacuum conveyor belt including a further suction device for sucking up the individual security documents conveyed on the topside of the first conveyor belt.

According to a further embodiment, the camera is located above the topside of the first conveyor belt or below the underside of the second conveyor belt upstream of the ejection unit.

When the quality control unit includes two or more cameras, one can be located above the topside of the first conveyor belt and one can be located below the underside of the second conveyor belt upstream of the ejection unit.

According to a second aspect, a method for processing a reel comprising adjacent security documents into a stack of individual security documents using a processing system comprising a reel unwinding unit, a cutting unit, a first conveyor belt, a second conveyor belt, a stacking unit, a quality control unit, and an ejection unit is provided. The method comprises: using the reel unwinding unit, unwinding the reel and feeding the adjacent security documents into the cutting unit; using the cutting unit, cutting the reel between the adjacent security documents to obtain individual security documents; conveying the individual security documents on a topside of the first conveyor belt arranged downstream of the cutting, the first conveyor belt conveying the individual security documents from the cutting unit to a second conveyor belt realized as a vacuum conveyor belt including a suction device provided on an underside of the second conveyor belt; taking images of the individual security documents using a camera of the quality control unit located above the topside of the first conveyor belt; determining, based on the image taken of each individual security document, whether the individual security document complies with predetermined quality criteria; using the suction device provided on the underside of the second conveyor belt, sucking up the individual security documents conveyed on the topside of the first conveyor belt; conveying the individual security documents sucked up from the first conveyor belt towards the stacking unit on the underside of the second conveyor belt; if it is determined that one of the individual security documents does not comply with the predetermined quality criteria, using the ejection unit to eject the individual security document which does not comply with the predetermined quality criteria from the underside of the second conveyor belt towards the bottom (in a correct mounting orientation of the processing system); and stacking, in the stacking unit, the individual security documents arriving on the underside of the conveyor belt which were not ejected by the ejection unit, the stacking unit at least partially facing the underside of the second conveyor belt. The embodiments and features described with respect to the processing system of the first aspect also hold for the processing method of the second aspect and vice versa. In particular, the processing system described in the method of the second aspect is the processing system as described in the first aspect or any embodiment thereof.

According to a third aspect, a stack of individual security documents processed according to the method of the second aspect or any embodiment thereof is provided.

The present invention will be described more fully hereinafter with reference to the accompanying figures in which like numerals represent like element throughout the different figures, and in which prominent aspects and features of the invention are illustrated.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 shows a processing system for processing a reel comprising adjacent security documents into a stack of individual security documents;

Fig. 2 shows a first view of a reel unwinding unit and a cutting unit pertaining to the processing system of Fig. 1 ;

Fig. 3 shows a second view of a reel unwinding unit and a cutting unit pertaining to the processing system of Fig. 1 , with the cutting unit being in the cutting position;

Fig. 4 shows a third view of a reel unwinding unit and a cutting unit pertaining to the processing system of Fig. 1 , with the cutting unit being in the non-cutting position;

Fig. 5 shows a view of a first conveyor belt pertaining to the processing system of Fig. 1 ;

Fig. 6 shows a view of a second conveyor belt pertaining to the processing system of Fig. 1 ;

Fig. 7 shows a view of an ejection unit pertaining to the processing system of Fig. 1 in the neutral state;

Fig. 8 shows a view of the ejection unit of Fig. 7 in the ejection state;

Fig. 9 shows a first view of a stacking unit pertaining to the processing system of Fig. 1 ;

Fig. 10 shows a second view of the stacking unit of Fig. 9;

Fig. 11 shows a third view of the stacking unit of Fig. 9; and

Fig. 12 shows a fourth view of the stacking unit of Fig. 9.

DETAILED DESCRIPTION

Fig. 1 shows a processing system 1 for processing a reel 2 comprising adjacent security documents 3 into a stack 4 of individual security documents 3. The processing system 1 includes a reel unwinding unit 5, a cutting unit 6, a first conveyor belt 7, a second conveyor belt 8, a stacking unit 9, a quality control unit 10 and an ejection unit 11 . The processing system 1 of Fig. 1 further includes a trigger sensor 12 as an optional feature. The individual components of the processing system 1 will be described below with reference to Fig. 1 to 12. In the example and orientation shown in the Figures, the upstream direction is toward the left side (towards the reel 2), and the downstream direction is towards the right side (towards the stacking unit 9).

The security documents 3 are here security labels each including a unique two-dimensional code, which are intended to be stuck on beverage bottles. The two dimensional code encodes a serial number of the bottle and allows authentication thereof. The security documents 3 are printed all adjacent to one another on a long stripe 13 of paper, and rolled into the reel 2. The purpose of the processing unit 1 is to unroll the reel 2, to cut into individual security documents 3 and stack them into the stack 4.

The reel unwinding unit 5 includes two identical unwinding components labelled 5a and 5b (see Fig. 1 to 4), which each include a pair of unwinding cylinders 51 , 52. The stripe 13 of adjacent security documents 3 passes between the two cylinders 51 , 52 forming a pair, which are arranged such as to just let the stripe 13 pass. The cylinders 51 , 52 rotate in opposite directions as illustrated in Fig. 2 by the arrows, thereby unwinding reel 2 due to the friction on their surface. The cylinders 51 , 52 can be made of a rubber material.

The cutting unit 6 is located between the reel unwinding components 5a, 5b and includes two cutting cylinders 61 , 62 rotating in opposite directions, as illustrated in Fig. 2. The stripe 13 of adjacent security documents 3 passes between the two cutting cylinders 61 , 62. The two cutting cylinders 61 , 62 each include a cutting edge 63 forming a cutting blade. When the cutting edges 63 of the two cutting cylinders 61 , 62 are aligned, as shown in Fig. 3, the stripe 13 is cut, thereby forming individual security documents 3. At all other times, when the cutting edges 63 are not aligned (see Fig. 4), the stripe 13 is not cut. The timing of the cutting is adjusted by adapting the speed of rotation of the cutting cylinders 61 , 62. The timing of the cutting is moreover triggered by the trigger sensor, which includes an imaging unit for visually detecting a separation line separating the adjacent security documents 3 and triggering the cutting unit 6 to cut the stripe 13 on the separation line, thereby obtaining individual security documents 3.

The unwinding component 5b (located downstream of the cutting unit 6) displaces the cut individual security documents 3 onto the first conveyor belt 7. As shown in Fig. 2, the unwinding speed v1 at which the reel unwinding unit 5 unwinds the reel 2 is smaller than the speed v2 of the first conveyor unit 7, thereby leaving a distance d between neighboring security documents 3 on the first conveyor belt 7. The first conveyor belt 7 is realized as a vacuum conveyor belt which includes small holes 73 in the belt 7 allowing an airflow 19 inwards, thereby holding the security documents 3 in place as they are transported by the first conveyor belt 7. The security documents 3 have their printed face facing upwards while they are transported on a topside 71 of the first conveyor belt 7 (and not on an underside 72 of the first conveyor belt 7). As shown in Fig. 5, the quality control unit 10 is arranged above the first conveyor belt 7. The quality control unit 10 includes a camera 15 and a quality determination unit 16. The camera 15 captures an image of each security document 3 passing under it on the first conveyor belt 7. The captured image is analyzed by the quality determination unit 16 to detect whether the stripe 13 was cut at the correct locations, and to determine whether the printed features on the security document 3, including the two-dimensional code, are readable. If this is confirmed, the quality determination unit 16 qualifies this security document 3 as a valid security document 3 (complying with the predetermined quality criteria), otherwise, the quality determination unit 16 qualifies this security document 3 as an invalid security document 3 (not complying with the predetermined quality criteria). The image captured by the camera 15 further allows deducing the position of the security documents 3, and the security documents 3 can hence be tracked.

As shown in Fig. 6, towards the downstream end of the first conveyor belt 7, the topside 71 of the first conveyor belt 7 faces an underside 82 of the second conveyor belt 8. In the area where the two conveyor belts 7, 8 overlap, the security documents 3 are transmitted to the second conveyor belt 8. Instead of being transported on the topside 81 of the second conveyor belt 8 as was the case for the first conveyor belt 7, the second conveyor belt 8 transports the security documents 3 on the underside 82 thereof. To this end, the second conveyor belt 8 is equally realized as a vacuum conveyor belt with holes 83 forming a suction device through an inward airflow 84. The second conveyor belt 8 runs at the same speed v2 as the first conveyor belt 7.

The ejection unit 11 is realized as a gate unit provided along the underside 82 of the second conveyor belt 8, as shown in Fig. 7 and 8. The ejection unit 11 is realized as a flat elongated metal piece which is arranged under the underside 82 of the second conveyor belt 8 and rotatable around a rotation axis 14. The ejection unit 11 is shown in its neutral state S1 in Fig. 7. There, the ejection unit 11 is maintained below the underside 82 of the second conveyor belt 8, letting the security document 3 past it without interfering with its trajectory. The security documents 3 that are not ejected by the ejection unit 11 are those forming the valid security documents 3. The ejection unit 11 is further shown in its ejection state S2 in Fig. 8. There, an upstream part of the ejection unit 11 is rotated upwards around the rotation axis 14 to form an angle with the underside 82 of the second conveyor belt 8 and intersect with the motion of the security document 3 transported on the underside 82 of the second conveyor belt 8. In the ejection state S2, fingers 17 of the ejection unit 11 come to grasp around the underside 82 of the second conveyor belt 8. That way, the ejection unit 11 disturbs the passage of the security document 3, which is distanced from the underside 82 of the second conveyor belt 8 and released from the suction mechanism holding the security document 3 on the underside 82 of the second conveyor belt 8. Accordingly, the ejection unit 11 ejects the security document 3 towards the bottom, where it is caught by a container. The ejection unit 11 is coupled with the quality control unit 10 such that the quality determination unit 16 sends a signal to the ejection unit 11 when an invalid security document 3 is detected, for ejection by the ejection unit 11. The ejection unit 11 thus allows ejecting only those security documents 3 which are invalid.

The stacking unit 9 is provided downstream of the ejection unit 11 such as to stack only valid security documents 3. As shown in Fig. 9 to 12, the stacking unit 9 is provided underneath the downstream end of the underside 82 of the second conveyor belt 8. The stacking unit 9 includes a support 91 , which is a platform on which the security documents 3 are stacked. The security documents 3 get released and stacked onto the stack 4 because the suction mechanism of the second conveyor belt 8 is turned off in the portion of the second conveyor belt 8 facing the stacking unit 9. Thereby, the security documents 3 are released and fall onto the stack 4 due to gravity. The security documents 3 are aligned with one another on the stack 4 by means of four bars 92 forming a frame for the stack 4.

As can be seen in Fig. 10, the support 91 moves downwards as the height of the stack 4 increases, such as to maintain a constant distance between the upper security document 3 of the stack 4 and the underside 82 of the second conveyor belt 8, thereby ensuring that newly arriving security documents 3 have room on the stack 4. As can be shown in Fig. 11 , when the stack 4 is finished, i.e. it has a predetermined number of security documents 3 piled up thereon (the predetermined number of security documents 3 in a stack 4 here being 500), a separator 18 is automatically inserted in a position substantially corresponding to the highest position of the support 91 , such as to face the underside 82 of the second conveyor belt 8. The separator 18 temporarily replaces the support 91 and the newly arriving security documents 3 are deposited thereon. In the meantime, the finished stack 4 is removed from the support 91.

As shown in Fig. 12, once the finished stack 4 was removed from the support 91 , the support 91 is moved back up and the separator 18 is removed, thereby leaving the security documents 3 that were piled up thereon to lie on the support 91. The cycle then starts all over (Fig. 9 to 12), with the new stack 4 increasing size, the support 91 accordingly moving down, the stack 4 being removed while inserting a separator 18, and the support 91 being put back into position.

The above disclosed subject-matter is to be considered illustrative, and not restrictive, and serves to provide a better understanding of the invention defined by the independent claims.

REFERENCE NUMERALS

1 processing system

2 reel

3 security document

4 stack

5 reel unwinding unit 5a unwinding component

5b unwinding component

6 cutting unit

7 first conveyor belt

8 second conveyor belt

9 stacking unit

10 quality control unit

11 ejection unit

12 trigger sensor

1 rotation axis

13 stripe

15 camera

16 quality determination unit

17 finger

18 separator

19 airflow

51 unwinding cylinder

52 unwinding cylinder

61 cutting cylinder

62 cutting cylinder

63 cutting edge

71 topside

72 underside

73 hole

81 topside

82 underside

83 suction device

84 airflow

91 support

92 bar

Claims

1. A processing system (1 ) for processing a reel (2) comprising adjacent security documents (3) into a stack (4) of individual security documents (3), the processing system (1 ) comprising: a reel unwinding unit (5); a cutting unit (6); a first conveyor belt (7); a second conveyor belt (8); a stacking unit (9); a quality control unit (10); and an ejection unit (11); wherein the reel unwinding unit (5) is configured to unwind the reel (2) and to feed the adjacent security documents (3) into the cutting unit (6); the cutting unit (6) is configured to cut the reel (2) between the adjacent security documents (3) to obtain individual security documents (3); the first conveyor belt (7) is arranged downstream of the cutting unit (6) and is configured to convey the individual security documents (3) on a topside (71) of the first conveyor belt (7), the first conveyor belt (7) being configured to convey the individual security documents (3) from the cutting unit (6) to a second conveyor belt (8); the second conveyor belt (8) is realized as a vacuum conveyor belt including a suction device provided on an underside (82) of the second conveyor belt (8) for sucking up the individual security documents (3) conveyed on the topside (71 ) of the first conveyor belt (7), the second conveyor belt (8) being configured to convey the individual security documents (3) sucked up from the first conveyor belt (7) towards the stacking unit (9) on the underside (82) of the second conveyor belt (8); the quality control unit (10) includes a camera (15) for taking images of the individual security documents (3), and a quality determination unit (16) for determining, based on the image taken of each individual security document (3), whether the individual security document (3) complies with predetermined quality criteria; the ejection unit (11 ) is provided along the second conveyor belt (8) and has two states being a neutral state (S1 ) and an ejection state (S2), whether in the neutral state (S1), the ejection unit (11 ) does not act on the individual security documents (3) conveyed to the stacking unit (9) by the second conveyor belt (8), and in the ejection state (S2) which is triggered by the quality control unit (10) determining that one of the individual security documents (3) does not comply with the predetermined quality criteria, the ejection unit (11) ejects the individual security document (3) which does not comply with the predetermined quality criteria from the underside (82) of the second conveyor belt (8) towards the bottom in a correct mounting orientation of the processing system (1 ); and the stacking unit (9) is provided such that it at least partially faces the underside (82) of the second conveyor belt (8) and is configured to stack the individual security documents (3) arriving on the underside (82) of the conveyor belt which were not ejected by the ejection unit (11 ).

2. The processing system according to claim 1, wherein the stacking unit (9) comprises a support onto which the individual security documents (3) are stacked from above in the correct mounting orientation of the processing system (1), the support being configured to gradually be displaced downwards as the individual security documents (3) are stacked such as to maintain a constant distance between the underside (82) of the second conveyor belt (8) and the uppermost individual security document (3) of the stack (4).

3. The processing system according to claim 1 or 2, wherein the ejection unit (11 ) is realized as: a deactivation unit for temporarily and locally switching off a suction functionality of the suction device when the ejection unit (11 ) is in the ejection state (S2), thereby releasing the individual security document (3) which does not comply with the predetermined quality criteria from the underside (82) of the second conveyor belt (8) towards the bottom; and/or a gate unit which is a mechanical element that is provided alongside the second conveyor belt without touching the individual security documents (3) when the ejection unit (11 ) is in the neutral state (S1 ), and which is configured to be rotated and/or moved when the ejection unit (11 ) is in the ejection state (S2) such as to mechanically interrupt and/or modify a path of the individual security document (3) which does not comply with the predetermined quality criteria and to eject it from the underside (82) of the second conveyor belt (8) towards the bottom.

4. The processing system according to any one of claims 1 to 3, wherein an unwinding speed (v1) of the reel unwinding unit (5) is smaller than a speed (v2) of the first conveyor belt (7).

5. The processing system according to any one of claims 1 to 4, wherein the stacking unit (9) includes a separator which is configured to be inserted above a finished stack (4) having reached a predetermined height or a predetermined number of individual security documents (3), wherein the separator is configured to temporarily hold the subsequently arriving individual security documents (3) while the finished stack (4) is being removed.

6. The processing system according to any one of claims 1 to 4, which comprises several stacking units (9) and a displacement unit, wherein the displacement unit is configured to switch the position of the stacking units (9) such that one of the stacking units (9) is always at least partly facing the underside (82) of the second conveyor belt (8), the displacement unit being configured to displace a current stacking unit (9) currently at least partly facing the underside (82) of the second conveyor belt (8) when the stack (4) of individual security documents (3) in the current stacking unit (9) reaches a predetermined height or a predetermined number of individual security documents (3) and to replace it by an empty stacking unit (9).

7. The processing system according to any one of claims 1 to 6, wherein the individual security documents (3) are tax stamps, labels or banknotes.

8. The processing system according to any one of claims 1 to 7, wherein the first conveyor belt (7) is realized as a vacuum conveyor belt including a further suction device for sucking up the individual security documents (3) conveyed on the topside (71 ) of the first conveyor belt (7).

9. The processing system according to any one of claims 1 to 8, wherein the camera (15) is located above the topside (71) of the first conveyor belt (7) or below the underside (82) of the second conveyor belt (8) upstream of the ejection unit (11 ).

10. Method for processing a reel (2) comprising adjacent security documents (3) into a stack (4) of individual security documents (3) using a processing system (1 ) comprising a reel unwinding unit (5), a cutting unit (6), a first conveyor belt (7), a second conveyor belt (8), a stacking unit (9), a quality control unit (10), and an ejection unit (11 ); wherein the method comprises: using the reel unwinding unit (5), unwinding the reel (2) and feeding the adjacent security documents (3) into the cutting unit (6); using the cutting unit (6), cutting the reel (2) between the adjacent security documents (3) to obtain individual security documents (3); conveying the individual security documents (3) on a topside (71) of the first conveyor belt (7) arranged downstream of the cutting, the first conveyor belt (7) conveying the individual security documents (3) from the cutting unit (6) to a second conveyor belt (8) realized as a vacuum conveyor belt including a suction device provided on an underside (82) of the second conveyor belt (8); taking images of the individual security documents (3) using a camera (15) of the quality control unit (10) located above the topside (71 ) of the first conveyor belt (7); determining, based on the image taken of each individual security document (3), whether the individual security document (3) complies with predetermined quality criteria; using the suction device provided on the underside (82) of the second conveyor belt (8), sucking up the individual security documents (3) conveyed on the topside (71) of the first conveyor belt (7); conveying the individual security documents (3) sucked up from the first conveyor belt (7) towards the stacking unit (9) on the underside (82) of the second conveyor belt (8); if it is determined that one of the individual security documents (3) does not comply with the predetermined quality criteria, using the ejection unit (11) to eject the individual security document (3) which does not comply with the predetermined quality criteria from the underside (82) of the second conveyor belt (8) towards the bottom in a correct mounting orientation of the processing system (1 ); and stacking, in the stacking unit (9), the individual security documents (3) arriving on the underside (82) of the conveyor belt which were not ejected by the ejection unit (11), the stacking unit (9) at least partially facing the underside (82) of the second conveyor belt (8).

11. The method of claim 10, wherein the processing system (1 ) is the processing system (1 ) according to any one of claims 1 to 9.

12. A stack (4) of individual security documents (3) processed according to the method of claim 10 or 11.