Device and method for printing on one or both sides of multiple flat objects

Abstract

An apparatus for printing on one or both sides of a flat object, comprising: an annular conveying path for the flat object, which is arranged to convey the objects thereon individually in a first section of the conveying path and as a (partial) stack of several objects in a second section; a feed conveyor, which is arranged to feed the objects to be printed individually upstream of the printing press into the first section of the conveying path; a printing press, which is arranged along the first section of the conveying path and is adapted to print one by one on the side facing the printing press the objects to be printed fed through the first section of the conveying path; a first discharge conveyor, which is arranged and controlled to discharge one by one the objects to be printed from the first section towards the second section downstream of the printing press; a first collector for the objects, the first collector being arranged at the second section downstream of the first discharge conveyor and being adapted to collect the objects discharged from the first discharge conveyor into a stack; a stacking conveyor for the (partial) stack of objects from the first collector, the stacking conveyor being arranged and adapted to convey the (partial) stack of objects along the second section; a second collector, which is arranged at the second section and is adapted to receive at least one (partial) stack conveyed along the second section by the stacking conveyor and to introduce the objects thereof individually into the first section upstream of the printing press.

Description

Technical Field

[0001] The present invention discloses an apparatus and method for printing on one or both sides of a flat object. Aspects of the apparatus and method are defined in the specification, as well as in the drawings and claims. The flat object is particularly understood to be a paper or plastic card, such as a financial card like a credit card and a bank card, an identity card, a driver's license, a gift card, etc., which is to be personalized or otherwise processed, especially for identification purposes. Background Art

[0002] Printing, especially personalizing such flat objects, especially cards, is usually carried out on both sides (front and back). However, cards printed on one side are also often required. For example, from EP3130646B1, a labeling system of an on-demand inkjet - DOD - inkjet printer with a single - pass printing process is known. Such a single - pass printer has multiple print heads in the transport direction of the flat object to be printed. Each print head connected to an ink container has multiple print nozzles for printing a specific color (cyan, magenta, white, black, etc.). Each print head extends across the entire width of the flat object transversely to the transport direction. In such a printing system, due to the lack of a corresponding fine and complex mechanical structure and control, the flat object cannot stop and rotate under the print head. The cost of the printing system components (printer, ink drying station, etc.) is very high. For small and medium production volumes, a dual / multi - print path is uneconomical. For two such marking systems, where one marking system is arranged behind the other for the front and back of such flat objects, a structural length / footprint of manufacturing equipment that is not always available is required. In addition, the cost for this is not always economically reasonable.

[0003] DE202003160086U1 relates to a card processing system, including a card processing path, a card printing mechanism arranged along the card processing path, the card printing mechanism including a main card movement path along which the card can move downstream, a printing station on the main card movement path, the printing station performing a printing operation on the surface of the card on the main card movement path, a card return movement path, and the card that has passed through the printing station can be deflected from the main card movement path along each card return movement path and returned to a position upstream of the printing station on the main card movement path to pass through the printing station again.

[0004] The method described there of feeding each card along the main card movement path to the printing station and then returning each card to be printed on both sides separately to the front of the printing station via the card return movement path has some drawbacks.

[0005] In the above prior art, the length of the card return path related to the speed of each card to be printed on both sides along the card return path and (for cards to be printed on one side and both sides) their number on the return path affect the order of the cards at the output of the printing station. Additionally, the residence time of a single card in each of the multiple stations along the main card movement path affects the printing process, making it more difficult to determine the order of the cards at the output end of the printing station.

[0006] There is another drawback when transporting single cards. Especially if several personalization processes are combined on a production line (such as electronic coding / personalization of integrated circuits or optical personalization by laser marking). Generally, these processes have quite unique and mostly different application-related processing times. In the case of continuous single-card transport without a card buffer function, the different cycle times from the individual processes are difficult to compensate for and cannot be coordinated to adapt to efficient production. Summary of the Invention

[0007] To avoid these drawbacks, an apparatus and method for printing on one or both sides of a flat object are disclosed herein. The proposed solution is particularly advantageous for medium and small production batches (1000 - 3000).

[0008] Objects of the type described herein include security or identity documents, such as passes, identity cards, driver's licenses, identity cards, credit cards, bank cards, cash cards, labels, passes, etc.

[0009] Documents of the type proposed herein as security or identity documents are generally produced centrally in their original form, i.e., without personalized data, and then personalized decentralized, for example, at a registration office, a public authority or at a company authorized to issue such documents. During personalization, personalized data (e.g., the name and address of the holder, date of birth, place of birth, photograph of the holder, biometric data of the holder, etc.) uniquely identifying the respective holder of the security or identity document, as well as the issue date and expiration date of the document, are incorporated into the security or identity document in the form of text, digital, and / or image data. This text, digital, and / or image data is at least partially directly readable by an observer. At least for the application of personalized data to the object, and also for their original design, the solution proposed herein is contemplated and can be used.

[0010] The device proposed in this text for printing on one or both sides of a flat object includes: an annular conveying path for the flat object, the conveying path being arranged to convey the object individually along a first section of the conveying path and to convey a (partial) stack including a plurality of objects along a second section of the conveying path; an input conveyor adapted to individually input the object to be printed into the first section of the conveying path upstream of the printing press; a printing press provided along the first section of the conveying path and adapted to print on the side of the object facing the printing press that is fed individually through the first section to the printing press; a first discharge conveyor arranged and controlled to discharge one by one from the first section towards the second section the objects to be printed on both sides downstream of the printing press; a first collector for the objects, the first collector being arranged at the second section downstream of the first discharge conveyor and arranged to collect the objects discharged from the first discharge conveyor into a stack; a stacking conveyor for the (partial) stack of objects from the first collector, the stacking conveyor being arranged and adapted to convey the (partial) stack of objects along the second section; a second collector arranged at the second section, the second collector being adapted to receive at least one (partial) stack conveyed along the second section by the stacking conveyor and to supply its objects individually to the first section upstream of the printing press.

[0011] In a variant of the proposed solution, a second discharge conveyor is provided, which is arranged to individually discharge objects from the annular conveying path downstream of the printing press.

[0012] The proposed solution is particularly suitable for medium and small production volumes. The objects to be labeled are first collected into a stack of objects and then transported in batches to be printed / personalized individually again. Larger production orders can also be logically and physically divided into partial stacks. Through this stack formation, the first side of the objects within such a stack is first personalized. Then, such a stack or partial stack including at least two or more documents is again supplied as a whole to the printing section in order to personalize the other side (multiple other sides) of the objects.

[0013] In a variant of the device, the first collector is arranged to discharge one (partial) stack at a time for picking up by the stacking conveyor once the defined height of the first stack or (partial) stack is reached, such (partial) stack being at least two or more in height of the flat objects.

[0014] In a variant of the device, the first section of the conveying path includes a circular or belt conveyor. In a variant of the device, the second section of the conveying path includes an arm or gantry robot, or an orbital conveyor.

[0015] In a variant of the apparatus, the stacking conveyor is arranged and configured to turn over a (partial) stack of objects between a first collector and a second collector in such a way that, in each case, the non-printed side of the objects being conveyed to the printing press faces the printing press for printing after leaving the second collector.

[0016] In a variant of the apparatus, the second collector is arranged and configured to discharge the individual objects of the (partial) stack and turn them over in the process, such that, in each case, the non-printed side of the objects being supplied to the printing press faces the printing press for printing after leaving the second collector.

[0017] Alternatively, upstream of the printing press, before the station for preprocessing the objects on the first section, there is a turning station for turning the individual objects by 180 degrees. This means that the objects from the second collector do not have to be turned over by the stacking conveyor or the second collector. This allows for a simpler design of the stacking conveyor and / or the second collector.

[0018] In a variant of the apparatus, the first section of the conveying path is arranged to continuously transport objects at a number of workpieces per unit time that is at least twice the number of workpieces per unit time at which the inlet conveyor conveys objects continuously or intermittently. In this variant of the apparatus, a buffer memory is provided between the input conveyor belt and the first section of the conveying path and is arranged to input the objects input by the input conveyor into the first section of the conveying path as successive groups of a plurality of objects, where the successive groups are spaced apart. In a variant of the apparatus, the objects are input as individually spaced-apart objects. In this case, the objects can be input into the first section in an inverted manner.

[0019] In a variant of the apparatus, the first section of the conveying path is arranged to feed the objects upstream of the printing press to a cleaning station and / or an input inspection station, and / or to feed the objects downstream of the printing press to a drying station and / or an output inspection station.

[0020] In a variant of the apparatus, the stacking conveyor includes grippers that are configured and arranged to grip and remove a (partial) stack of objects from the first collector and place and release them in the second collector. In a variant, the first collector and the second collector have only partially enclosed housings and have open housing surfaces. In particular, one side wall is largely open. This allows the grippers to remove a (partial) stack of objects from the first collector / place a (partial) stack of objects into the second collector.

[0021] In a variant of the device, the first collector and / or the second collector includes a spacer, the spacing of which can be adjusted so as to form a partial stack of a predetermined height / number of objects spaced apart from each other in the height direction. This provides the advantage that the collection of the objects discharged by the first discharge conveyor in the first collector and the conveyance of the (partial) stack to the stacking conveyor can overlap in time. Similarly, this applies to the discharge of the individual objects of the (partial) stack and the picking up of the (partial) stack conveyed by the stacking conveyor by the second collector.

[0022] In a variant of the device, the read / write device is arranged along the conveying path and is configured to write information into a magnetic stripe arranged on the object and into an IC (integrated circuit) embedded in the object. In a variant of the device, the read / write device is configured to perform the writing of information either individually for each object or as a collective entry.

[0023] In a variant of the device, along the conveying path, devices for laminating, stamping, and / or embossing each object are provided upstream or downstream of the printing press.

[0024] In a variant of the device, the printing press is a single-pass inkjet printing press having a plurality of print heads arranged in series in the conveying direction of the object to be printed, in particular for ultraviolet (UV) curable ink, and includes one or more containers, each containing a different color of ultraviolet (UV) curable ink. In other variants, the printing press is a multi-pass printing press.

[0025] In a variant, the first collector has a piston that is arranged and configured to discharge an expected number of objects from the first collector to the stacking conveyor. In a variant, the stacking conveyor is designed as a container, and recesses for receiving the objects pushed in by a pusher located in the first collector are provided in the side wall of the container.

[0026] In a variant, the second collector is arranged to receive the (partial) stack removed from the first collector by the stacking conveyor and conveyed along the second section of the conveying path to the second collector. In a variant, the second collector and the stacking conveyor are arranged such that they are positioned relative to each other in such a way that the objects are pushed out as a complete stack by a pusher arranged in the stacking conveyor and pushed into the space between two toothed belts of the second collector. In a variant, the second collector is configured to move its two toothed belts by one pitch through its driven rollers so as to discharge the objects from the lowest position of the two toothed belts of the second collector onto the first section of the conveying path.

[0027] The method disclosed herein is used for printing on one or both sides of a flat object, in particular using a device having the above-mentioned characteristics, wherein

[0028] - on an annular conveying path, the objects are conveyed individually on a first section of the conveying path and as a (partial) stack of objects on a second section of the conveying path;

[0029] - by means of a feed conveyor, the objects to be printed are fed individually into the first section of the conveying path upstream of the printing press;

[0030] - by means of the printing press arranged along the first section of the conveying path, the objects fed individually to the printing press are printed on the side facing the printing press;

[0031] - by means of a first discharge conveyor, downstream of the printing press, in the direction from the first section of the conveyor path to its second section, the objects to be printed on both sides are discharged individually;

[0032] - by means of a first collector at the second section of the conveying path arranged downstream of the first discharge conveyor, the objects discharged from the first discharge conveyor are collected into a stack;

[0033] - by means of a stack conveyor, the (partial) stack of the objects from the first collector is conveyed along the second section of the conveying path;

[0034] - by means of a second collector arranged at the second section of the conveying path, at least one (partial) stack conveyed along the second section of the conveying path by the stack conveyor is picked up, and its objects are fed individually into the first section of the conveying path upstream of the printing press.

[0035] In a variant of the method, a second discharge conveyor is used to discharge the objects individually from the annular transport path downstream of the printing press.

[0036] In a variant of the method, once the first stack or the defined height of the (partial) stack is reached, the (partial) stack is removed from the first collector by the stack conveyor and conveyed along the second section of the conveying path to a second collector arranged at the second section of the conveying path and deposited therein.

[0037] In another variant of the method, once the defined height of the first stack or (partial) stack has been reached, where the (partial) stack at least partly comprises the first stack and is the height of at least two or more flat objects, the (partial) stack as a whole is fed onto a second stack in a second collector at the end of the second section of the annular conveying path.

[0038] In a further variant of the method, the (partial) stack is turned over as it passes through the second section of the annular conveying path.

[0039] In another variant of the method, objects printed on their second side are partially discharged from the second collector and fed into the first section, fed to the printing press and finally discharged from the annular transport path at the end of the first section.

[0040] In a further variant of the method, the second collector delivers the individual objects of the (partial) stack and turns them over in the process, such that in each case the unprinted side of the object fed to the printing press faces the printing press for printing after leaving the second collector.

[0041] In another variant of the method, the first section of the conveying path continuously transports objects at a number of workpieces per unit time which is at least twice the number of workpieces per unit time at which the inlet conveyor conveys objects continuously or intermittently.

[0042] In a further variant of the method, between the inlet conveyor and the first section of the conveying path, a buffer memory transports the objects fed by the inlet conveyor into the first section of the conveying path as successive groups of objects, where the successive groups are spaced apart. In another variant of the method, the buffer memory carries the objects as individually spaced-apart objects. In both variants, the objects are fed into the first section in a turned-over or non-turned-over form, depending on the requirements / design of the buffer memory.

[0043] Alternatively or additionally, the first section of the conveying path feeds the objects to a cleaning station and / or an input inspection station upstream of the printing press, and / or feeds the objects to a drying station and / or an output inspection station downstream of the printing press.

[0044] In another variant of the method, the gripper of the stacking conveyor grips the (partial) stack of objects in the first collector and removes the (partial) stack of objects from it. At the end of the second section, the gripper also places the (partial) stack of objects in the second collector and releases the (partial) stack.

[0045] In a further variant of the method, the read / write device writes information along the transport path into a magnetic stripe arranged on the object, into an IC embedded in the object, while transporting a (partial) stack of the objects or the objects individually along the transport path, and the read / write device writes the information either individually for each object or as a collective entry.

[0046] For further technical background, see US7434728, US7398972, US4825054, US5266781, US6783067, US6902107, US6695205, US5943238, US6105493 and US2013 / 0220984. Description of the Drawings

[0047] Other objects, features, advantages and possible applications result from the following description of non-limiting examples of variants and the associated drawings. In the context of this document, all features described and / or illustrated, individually or in any combination, constitute the objects disclosed herein, regardless of their grouping in the claims or their reverse relationship. Based on the following description with reference to the drawings, possible variations will also become clear to a person skilled in the art. Thus, the figures schematically illustrate the devices discussed herein.

[0048] Figure 1 A variant of a device for printing on one or both sides of a plurality of flat objects is schematically illustrated.

[0049] Figures 2a-2d A variant of a first and a second collector and a stack conveyor is shown. Detailed Description

[0050] Figure 1 A device 10 for printing on one or both sides of a flat object K is shown. In the variant shown, the individual objects K are implemented as identity (ID) cards made of plastic. The device 10 has an annular transport path FW for the flat objects K. This transport path FW serves to transport the objects K as individual objects K on a first section 1A of the transport path FW and as a (partial) stack of a plurality of objects K on a second section 2A of the transport path FW. Then, the individual objects K are transported along the transport path FW.

[0051] In the variant shown here, the first section 1A of the conveying path FW is a loop conveyor or a belt conveyor, in which one or more endless conveyor belts 12 are guided over one or more driven and non-driven rollers. In the variant shown here, the second section 2A of the conveying path FW includes an overhead conveyor which conveys a gripper for a (partial) stack of objects K, which gripper can be moved in a controlled manner along a transport track TS and can be actuated in a controlled manner. In one variant, the gripper can also be rotated so that the orientation of the objects K in the (partial) stack is rotated by 180°.

[0052] The conveying path FW has, on an inflow side ( Figure 1 the left side in the drawing), a feed conveyor EF for the objects K. The feed conveyor EF serves to feed the objects K to be printed individually into the first section 1A of the conveying path FW on the upstream side of the printing press D. The printing press D is arranged along the first section 1A and serves to print on the objects K fed individually to the printing press D. A first discharge conveyor 1AF is arranged downstream of the printing press D and serves to discharge the objects K to be printed on both sides individually from the first section 1A of the conveying path FW in the direction of the second section 2A of the conveying path FW. In a variant not shown further, the first discharge conveyor 1AF includes one or more synchronously driven conveying sections which are arranged one behind the other in the conveying direction of the objects K.

[0053] The first discharge conveyor 1AF cooperates with a first collector 1S to convey the objects K as a (partial) stack S in the direction of the second section 2A of the conveying path FW. In this regard, in one variant, the first collector 1S is configured as a chute corresponding to the size of the objects K, and the first discharge conveyor 1AF introduces the individual objects K into the chute one by one. The first collector 1S is arranged downstream of the first discharge conveyor 1AF, at the second section 2A of the conveying path FW. It serves to collect the individual objects K discharged individually by the first discharge conveyor 1AF from the first section 1A of the conveying path FW in a stack S.

[0054] The first collector 1S is also arranged to discharge one (partial) stack S at a time for picking up by a stack conveyor SF once a defined height of the first stack or the (partial) stack has been reached. Such a (partial) stack, which includes at least two or more (for example 5, 10, 20, 40, 50 or 100 etc. objects K) of the flat objects K, is high.

[0055] The stacking conveyor SF cooperating with the first collector 1S is used to remove one (partial) stack S of objects K from the first collector 1S each time, and send out the stack S along the second section 2A of the conveying path FW. The stacking conveyor SF conveys the (partial) stack S of objects K along the second section 2A of the conveying path FW to the second collector 2S for the objects K. In Figure 1 it, the stacking conveyor SF is shown in dashed lines at the middle and right positions along the conveying track TS.

[0056] The second collector 2S is also arranged at the second section 2A of the conveying path FW. The second collector 2S is used to receive the (partial) stack S removed from the first collector 1S by the stacking conveyor SF and conveyed along the second section 2A of the conveying path FW to the second collector 2S.

[0057] The stacking conveyor SF is also used to turn over the (partial) stack S between the first and second collectors 1S, 2S in such a way during the transportation of the (partial) stack S along the second section 2A that the unprinted face of the object K to be conveyed to the printing press D after leaving the second collector 2S in each case faces the printing press for printing. The (partial) stack S is turned over between the first collector 1S and the second collector 2S. In Figure 1 the shown variant, this is achieved by the stacking conveyor SF as a gripper which carries the (partial) stack S located between its arms in an inverted U-shaped path from the first collector to the second collectors 1S, 2S. Obviously, the orientation of the object K is rotated by 180° during this process without any active rotation of the gripper.

[0058] If the object K to be printed on both sides has been printed twice, or if the object K to be printed on one side has been printed once and does not need to be printed again or printed on the opposite side, the object K is discharged from the conveying path FW by means of the second discharge conveyor 2AF. In the shown variant, the second discharge conveyor 2AF is designed as a belt conveyor which discharges the object K individually from the annular conveying path FW downstream of the printing press D. The first section 1A of the conveying path FW is used to continuously convey the object K at a workpiece number per unit time (e.g., 4000 uph) which is at least twice the workpiece number per unit time (e.g., 2000 uph) of the inlet conveyor EF for continuously or cyclically conveying the object K. A buffer storage PS can be provided between the inlet conveyor EF and the first section 1A of the conveying path FW, which is used to temporarily delay / synchronize the entry of the objects and enter the object K entering the first section 1A of the conveying path FW from the inlet conveyor EF as a continuous group of multiple objects K.

[0059] Furthermore, the second collector 2S is used to enable the objects K conveyed as (partial) stacks S along the second section 2A to enter individually into the first section 1A of the conveying path FW on the upstream side of the printing press D. The second collector 2S is used to supply the individual objects K to the first section 1A of the conveying path FW on the downstream side of the (optional) buffer storage PS. The second collector 2S brings the separated objects K to the downstream side of the (optional) buffer storage PS, onto the circulating conveyor belt TB of the conveying path FW, which conveyor belt feeds the objects K onto the conveyor belt of the first section 1A of the conveying path FW, which conveyor belt runs continuously at approximately twice the upm (units per hour).

[0060] Here, successive groups of a plurality of objects K can be spaced apart from one another in the manner of K-K-L-L-K-L-L... or K-K-L-L-L-K-K-L-L... etc., where L represents an empty space and K represents the space into which the object K can be placed in a controlled manner from the second collector 2S on the downstream side of the buffer memory. Alternatively, as Figure 1 shown, the individually spaced objects K can enter in the manner of K-L-K-L-K-L-L.... Furthermore, the buffer storage PS can input the inverted objects K into the first section 1A, as Figure 1 shown. In a variant not shown further, another station for flipping the object K is arranged before or after the buffer storage PS. Thus, even in the variant where the buffer storage PS flips the supplied objects, if required, the original orientation can be maintained by flipping the object K twice.

[0061] Along the first section 1A of the conveying path FW, on the upstream side of the printing press D, a plurality of stations are provided for preparing the objects K for printing. In the illustrated variant, these are stations V1 for increasing the ink adhesion by means of plasma or corona treatment, and stations V2 for cleaning the surface of the object K to be printed, for example by means of a cleaning roller. Before being introduced into the printing press D, an input inspection EI of each object K is carried out by means of an imaging camera. Along the first section 1A of the conveying path FW, on the downstream side of the printing press D, a plurality of stations are provided for post-processing the objects K after printing. After the printing press D has printed the object K, the object K is successively fed to a station N1 for pre-drying (pinning) the ink by means of (UV) light irradiation, a station N2 for applying a covering gloss surface that can overlap the printed image printed by the printing press D to at least a part of the object, a station N3 for curing the covering and the ink (if required) by means of (UV) light irradiation, and a station AI for inspecting the printed data / content and output inspection by means of an imaging camera.

[0062] In the illustrated variant, the printing press D is a single-pass inkjet printing press having a plurality of ultraviolet (UV) curable ink printheads arranged in series in the conveying direction of the object K to be printed and including containers for one or more different colors of UV curable ink. Each printhead associated with an ink container has a plurality of printing nozzles for printing a specific color (cyan, magenta, white, black, etc.). Each printhead extends across the entire width of the flat object transversely to the conveying direction.

[0063] Along the conveying path FW, on Figure 1 the second section 2A of, there is arranged a read / write device LSE. It is used to write information into the IC embedded in the object K. In the illustrated variant, the read / write device LSE is arranged to perform the writing of information as a collective entry when the stack is conveyed past the read / write device LSE. In other variants, such a read / write device LSE is missing.

[0064] In a variant not further shown, along the conveying path FW, devices for laminating, stamping, and / or embossing the object K are provided on the upstream side or the downstream side of the printing press D.

[0065] It should be understood that depending on the equipment required by the device, not all stations or other stations can be provided upstream and downstream of the printing press D.

[0066] During single-sided printing, objects K in the form of cards are continuously supplied to the device at 2000 upm. The buffer memory PS receives the objects K and transfers them to the independently driven input conveyor EF. For example, two objects K are placed close to each other on the continuously running input conveyor EF at 4000 upm at a speed suitable for the printing process. The above pattern with a gap between the objects K is created. Figure 1 It shows how the object K is discharged individually from the buffer memory PS using the gap, whereby the flipped object K from the second collector 2S is inserted into each gap in a controlled manner, as further explained below.

[0067] The next steps are to clean and inspect the incoming object K, and then the object K is printed by the printing press D (here a single-pass printing press) with UV ink. After the object K is printed by the printing press D, the object K is successively fed to a station N1 downstream of the printing press D for pre-drying (pinning) the ink by (UV) light irradiation, a station N2 for applying a covering gloss surface, a station N3 for curing the covering gloss surface and (if necessary) curing the ink by (UV) light irradiation, and a station AI for inspecting the printed data / content by an imaging camera and outputting the inspection. A masking gloss surface is applied to at least a part of the object, and this part can overlap with the printed image.

[0068] Cards detected as NOK (bad) by the output inspection AI are ejected into a separate bad tray at the end of the device, which is not shown further.

[0069] For double-sided or multi-sided printing, after printing and inspecting one side, the objects K are stacked in the first collector 1S. Once the stack height depending on the job size has been reached, the stack is picked up by the stack conveyor SF. The stack conveyor SF conveys the (partial) stack S of cards along the second section 2A of the conveying path FW to the second collector 2S. During transportation, the objects K are turned in units of the (partial) stack S and finally enter the second collector 2S. From this second collector 2S, the turned cards K are conveyed one by one to the first section 1A of the conveying path FW on the upstream side of the printing press D. Subsequently, the above steps are performed to perform single-sided printing on the other side of each object. If the object K to be printed is not a two-page one, but a document with more than two pages, such as a passport booklet, a page-turning station can also be provided on the upstream side of the printing press D in the first section 1A of the conveying path. This page-turning station is located in the first section 1A of the conveying path.

[0070] In some variants, the first collector 1S and the second collector 2S have spacers AH, the spacing of which can be adjusted to form partial stacks of a predetermined height / number of objects spaced apart from each other in the height direction. Thus, the collection of objects discharged by the first discharge conveyor by the first collector 1S and the delivery of the (partial) stack S to the stack conveyor SF can overlap in time. Similarly, this applies to the delivery of the individual objects of the (partial) stack S and the picking up of the (partial) stack S conveyed by the stack conveyor SF by the second collector 2S.

[0071] Figures 2A - 2d show a variant 1AF' of the first discharge conveyor, which cooperates with a variant 1S' of the first collector to move the objects K as a (partial) stack S in the direction of the second section 2A of the conveying path FW on this path. Thus, in this variant, the first collector 1S' is designed as a lifting device corresponding to the size of the objects K. In one variant, this lifting device is arranged in the first collector 1S Figure 1A conveyor belt disposed horizontally at a position in [the relevant context] and adjacent to the first section 1A of the conveying path FW to bring the object K onto the second section 2A of the conveying path FW. The lifting device is used to discharge the object K from the first section 1A of the conveying path FW individually by the first discharge conveyor 1AF' and collect them into a stack S at intervals so that the objects K do not touch each other. This is intended to prevent the as-yet-unfully-cured printed image on one of the objects K from rubbing against the surface of an adjacent object K after the object K has been printed on one side. To achieve this, the object K is individually pushed laterally to the conveying direction of the conveying path FW by a pusher (not shown in detail) and inserted between the two toothed belts ZR1, ZR2 at the lowest position of the lifting device. Therefore, the two toothed belts ZR1, ZR2 of the lifting device are moved by one pitch through their driven rollers AR1 and AR2. Thus, the lowest position of the lifting device is again free to receive the next object K from the first section 1A of the conveying path FW. Once the expected number of objects K has been picked up in the lifting device of the first collector 1S', that number of objects K is delivered in the lifting device to Figure 2b , 2c , the stack conveyor variant SF' shown in 2d, and the objects K do not touch each other during the transfer process. This prevents adjacent objects K from inking each other or blurring their printed images, or prevents the printed surface of the object K from soiling the unprinted surface of an adjacent object K with ink.

[0072] The first collector 1S' is also arranged to discharge one (partial) stack S at a time for picking up by the stack conveyor SF' once the first stack or the defined height of the (partial) stack has been reached, and such (partial) stacks of at least two or more (e.g., 5, 10, 20, 40, 50, or 100, etc. objects K) of the flat objects K are tall.

[0073] The stack conveyor SF' cooperating with the first collector 1S' is used to pick up one of the (partial) stacks S in the objects K pushed out from the first collector 1S' and send them along the second section 2A of the conveying path FW.

[0074] In Figures 2a-2d the shown variant, this is achieved by designing the stack conveyor as a container in the side walls of which recesses corresponding to the pitch of the two toothed belts ZR1, ZR2 of the first collector 1S' are provided. With the pusher P located in the first collector 1S', the object K is pushed out from the first collector 1S' as a stack and into the recesses of the stack conveyor SF'.

[0075] Then, the stacking conveyor SF' conveys the (partial) stack S of the objects K along the second section 2A of the conveying path FW at the transport track TS to a second collector 2S' for the objects K (see Figure 1 ).

[0076] The second collector 2S' is also arranged on the second section 2A of the conveying path FW. The second collector 2S' is used to receive the (partial) stack S that is removed by the stacking conveyor SF' from the first collector 1S' and conveyed along the second section 2A of the conveying path FW to the second collector 2S'.

[0077] The stacking conveyor SF' is also used, during the conveyance of the (partial) stack S along the second section 2A, in such a way (from the orientation according to Figure 2b to the orientation according to Figure 2c ) to turn over the (partial) stack S between the first and second collectors 1S', 2S', that is, in each case, the unprinted side of the object K conveyed to the printing press D faces the printing press D for printing after leaving the second collector 2S'.

[0078] In this case, the orientation of the object K rotates by 180° (from the orientation according to Figure 2b to the orientation according to Figure 2c ), without the need for active rotation of the stacking conveyor SF'.

[0079] Similar to Figure 2a the first collector 1S' (except for the chute P), the second collector 2S' is also arranged along the second section 2A of the conveying path FW. The second collector 2S' is used to receive the (partial) stack S that is removed by the stacking conveyor SF' from the first collector 1S' and conveyed along the second section 2A of the conveying path FW to the second collector 2S'.

[0080] The second collector 2S' is also used to enable the objects K conveyed as a (partial) stack S along the second section 2A to enter the first section 1A of the conveying path FW individually on the upstream side of the printing press D. The second collector 2S' is also used to enable the objects K to enter the first section 1A of the conveying path FW individually on the downstream side of the (optional) buffer storage PS. The second collector 2S' brings the separated objects K to the downstream side of the (optional) buffer memory PS, to the circulating conveyor belt TB of the conveying path FW, which continuously runs at a speed approximately twice the upm (pieces per hour) of the first section 1A of the conveying path FW, and conveys the objects K to the conveyor belt of the first section 1A. As Figure 1 shown, the objects K from the second collector 2S' and the objects K from the buffer memory PS can be discharged onto the conveyor belt TB in a defined order.

[0081] To this end, the second collector 2S' and the stacking conveyor SF' are positioned such that the object K is pushed out as a complete stack by means of a pusher arranged in the stacking conveyor SF' and is pushed into the space between two toothed belts ZR1, ZR2 of the lowering device of the second collector 2S'. To discharge the separated object K, the two toothed belts ZR1, ZR2 are moved downward by one pitch by means of their driven rollers AR1 and AR2. As a result, the object K is delivered from the lowest position of the lowering device of the second collector 2S' onto the first section 1A of the conveying path FW. In summary, this effectively prevents the printed objects from contacting each other during processing. This prevents adjacent objects K from inking each other or blurring their printed images, or prevents the printed surface of the object K from soiling the unprinted surface of an adjacent object K with ink.

[0082] A read / write device is arranged along the conveying path FW. It is used to write information into an IC embedded in the object K. In the illustrated variant, the read / write device LSE is arranged to write information as a collective entry when the stack is conveyed past the read / write device LSE. In other variants, such a read / write device LSE is missing. Upstream of the second collector 2S', a read / write device LSE associated with, for example, the inlet conveyor EF can be installed. In one variant, the read / write device LSE includes, for example, a receiver in the form of a turntable that rotates (vertically) about a rotation axis, wherein the receiver positions are arranged in the circumferential direction of the turntable for receiving a plurality of objects K during the writing of information. In other variants, the read / write device LSE is associated with or located downstream of the second discharge device 2AF, which discharges the object K individually from the annular conveying path FW on the downstream side of the printing press D. The individual stations and functions of the device are coordinated and controlled by means of an electronic control ECU.

[0083] The variants of the above-described device and their construction and operation aspects are only intended to provide a better understanding of the structure, operation, and features; they do not limit the present disclosure to, for example, the described variants. The drawings are partially schematic, showing significant features and effects, in some cases significantly enlarged, to illustrate functions, operating principles, technical variants, and features. In this regard, each operating mode, principle, technical variant, and feature disclosed in the drawings or the text can be freely and arbitrarily combined with all the claims, and each feature in the text and other drawings can be combined with the principles, technical variants, and features included in or resulting from the present disclosure, such that all conceivable combinations can be assigned to the described method. This includes combinations between all individual variants in the text, i.e., each part of the description, the claims, as well as combinations between different variants in the text, the claims, and the drawings. Furthermore, the claims do not limit the present disclosure, and thus all possible combinations of the disclosed features with each other. All the disclosed features are also explicitly disclosed herein individually and in combination with all other features.

Claims

1. An apparatus for printing on one or both sides of a flat object, comprising: - an annular conveying path (FW) for the flat object (K), the conveying path (FW) being arranged to convey the object (K) individually along a first section (1A) of the conveying path (FW), and to convey a stack comprising a plurality of objects (K) along a second section (2A) of the conveying path (FW); - an inlet conveyor (EF) for the object (K), the inlet conveyor (EF) being arranged to feed the object (K) to be printed individually upstream of the printing press (D) into the first section (1A) of the conveying path (FW); - a printing press (D), which is arranged along the first section (1A) of the conveying path (FW) and is arranged to print the object (K) fed individually by the first section (1A) of the conveying path (FW) to the printing press (D); - a first discharge conveyor (1AF) for the object (K), the first discharge conveyor (1AF) being arranged and controlled to discharge the object (K) to be printed on both sides one by one from the first section (1A) of the conveying path (FW) downstream of the printing press (D) towards its second section (2A); - a first collector (1S) for the object (K), the first collector (1S) being arranged downstream of the first discharge conveyor (AF), at the second section (2A) of the conveying path (FW) and being adapted to collect the objects (K) discharged from the first discharge conveyor (1AF) into a stack; - a stack conveyor (SF) for the stack (S) of the objects (K) from the first collector (1S), the stack conveyor (SF) being arranged and adapted to convey the stack (S) of the objects (K) along the second section (2A) of the conveying path (FW); - a second collector (2S) for the object (K), the second collector (2S) being arranged at the second section (2A) of the conveying path (FW) and being adapted to receive at least one stack (S) conveyed by the stack conveyor (SF) along the second section (2A) of the conveying path (FW), and being adapted to introduce the objects (K) thereof individually upstream of the printing press (D) into the first section (1A) of the conveying path (FW), wherein the stack conveyor (SF) is arranged and configured to flip the stack (S) of the objects (K) between the first collector (1S) and the second collector (2S) in such a way that, in each case, the unprinted side of the object (K) to be conveyed to the printing press (D) faces the printing press (D) for printing after leaving the second collector (2S), by traveling from the first collector (1S) to the second collector (2S) along an inverted U-shaped path.

2. The apparatus according to claim 1, wherein, - The first collector (1S) is arranged to convey in each case the stack (S), which comprises at least two or more of the flat objects (K), to be received by the stack conveyor (SF) once a first stack or a defined height of the stack has been reached.

3. The apparatus according to claim 1 or 2, wherein, - a second discharge conveyor (2AF) for the objects (K) is provided and the second discharge conveyor is arranged to discharge the objects (K) individually from the annular conveying path (FW) on the downstream side of the printing press (D), or - a magazine is provided adjacent to the first collector (1S) and the magazine is arranged to receive the printed objects (K) on the downstream side of the printing press (D).

4. The apparatus according to claim 1 or 2, wherein, - the first section (1A) of the conveying path (FW) is arranged to convey the objects (K) continuously at a number of workpieces per unit time (uph) which is at least twice the number of workpieces per unit time at which the inlet conveyor (EF) conveys the objects (K) continuously or intermittently; and / or wherein - a buffer store (PS) is arranged between the inlet conveyor (EF) and the first section (1A) of the conveying path (FW) and the buffer store is arranged to feed the objects (K) from the inlet conveyor (EF) into the first section (1A) of the conveying path (FW) as successive groups of a plurality of objects (K), where the successive groups are spaced apart from one another, or as the objects (K) are spaced apart individually from one another, and / or are fed into the first section (1A) in an inverted manner.

5. The apparatus according to claim 1 or 2, wherein, - the first section (1A) of the conveying path (FW) is arranged to feed the objects (K) upstream of the printing press (D) to a cleaning station (R) and / or an input inspection station (EI), and / or to feed the objects (K) downstream of the printing press (D) to a drying station (T) and / or an output inspection station (AI), and / or wherein - the stack conveyor (SF) comprises grippers which are arranged and configured to grip and remove the stack (S) of the objects (K) in the first collector (1S) and to place and release it in the second collector (2S), and / or wherein - a circulating or belt conveyor is arranged which is adapted to receive objects from the second collector (2S) and to transfer the objects to a downstream transport section, and / or wherein - the printing press (D) is a single-pass inkjet printing press which comprises a plurality of print heads for ultraviolet (UV)-curable ink, the plurality of print heads being arranged in series in the conveying direction of the object (K) to be printed, and the printing press (D) comprises one or more containers with ultraviolet (UV)-curable ink of different colors, and / or wherein - Downstream of the printing press (D) along the conveying path (FW), a station (N1) for pre-drying the ink by means of (UV) light irradiation, a station (N2) for applying a covering gloss layer, and / or a station (N3) for curing the covering gloss layer by means of (UV) light irradiation are provided.

6. The device according to claim 1 or 2, wherein - The first collector (1S') is designed as a lifting device corresponding to the size of the object (K), and the lifting device is arranged to collect the objects (K) discharged individually from the first section (1A) of the conveying path (FW) in stacks (S) spaced apart from each other; wherein a pusher is arranged, which is adapted to push out the objects (K) one by one transversely to the conveying direction of the conveying path (FW) and to push the objects (K) between two toothed belts (ZR1, ZR2) of the lifting device; wherein corresponding driven rollers (AR1, AR2) are arranged, which are adapted to move the toothed belts (ZR1, ZR2).

7. The device according to claim 1 or 2, wherein - The first collector (1S') has a piston (SP), which is arranged and designed to convey a desired number of the objects (K) in the lifting device of the first collector (1S') to the stack conveyor (SF'), and / or wherein - the stack conveyor (SF') is designed as a container, and recesses for receiving the objects (K) pushed into the container by the pusher (P) spaced apart from each other and located in the first collector (1S') are provided in the side wall of the container.

8. The device according to claim 1 or 2, wherein - A second collector (2S') is arranged, which receives the stacks (S) removed from the first collector (1S') by the stack conveyor (SF'), conveyed along the second section (2A) of the conveying path (FW) and transferred to the second collector (2S'), and / or wherein - The second collector (2S') and the stack conveyor (SF') are arranged in such a way that they are positioned relative to each other such that the objects (K) are pushed out as a complete stack by means of a pusher arranged in the stack conveyor (SF') and are pushed between two toothed belts (ZR1, ZR2) of the second collector (2S'), and / or wherein - The second collector (2S') is arranged to move its two toothed belts (ZR1, ZR2) by one pitch by means of its driven rollers (AR1, AR2) in order to discharge the objects (K) from the lowest position of the two toothed belts (ZR1, ZR2) of the second collector (2S') onto the first section (1A) of the conveying path (FW) for discharging the objects (K).

9. A method for printing on one or both sides of a flat object, wherein - On a circular conveying path, the object is conveyed individually on a first section of the conveying path and as a stack of a plurality of objects on a second section of the conveying path; - By means of an inlet conveyor, the object to be printed is fed individually into the first section of the conveying path upstream of the printing press; - By means of the printing press arranged along the first section of the conveying path, the object conveyed individually towards the printing press is printed on the side facing the printing press; - By means of a first discharge conveyor, downstream of the printing press, in the direction from the first section of the conveying path to its second section, the object to be printed on both sides is discharged individually; - By means of a first collector arranged downstream of the first discharge conveyor at the second section of the conveying path, the objects discharged from the first discharge conveyor are collected into a stack; - By means of a stack conveyor, the stack of objects from the first collector is conveyed along the second section of the conveying path; - By means of a second collector arranged at the second section of the conveying path, at least one stack conveyed by the stack conveyor along the second section of the conveying path is picked up and its objects are fed individually into the first section of the conveying path upstream of the printing press; Wherein the stack conveyor (SF) is arranged and configured to travel from the first collector (1S) to the second collector (2S) along an inverted U-shaped path and to flip the stack (S) of objects (K) between the first collector (1S) and the second collector (2S) in such a way that, in each case, the unprinted side of the object (K) conveyed to the printing press (D) faces the printing press (D) after leaving the second collector (2S) for printing.

10. The method according to claim 9, wherein - Once the first stack or a defined height of the stack is reached, the stack is removed from the first collector by the stack conveyor and - the stack is conveyed along the second section of the conveying path to and placed in a second collector arranged at the second section of the conveying path; - Once the first stack or a defined height of the stack is reached, the stack at least partially comprises the first stack and is the height of at least two or more of the flat objects, the stack as a whole enters onto a second stack in the second collector at the end of the second section of the circular conveying path; - The objects for printing their second side are fed one by one from the second stack into the first section, into the printing press, and finally discharged from the circular conveying path at the end of the first section.

11. The method according to claim 9 or 10, wherein - The second collector discharges the individual objects of the stack and, in the process, turns them over such that, in each case, the non-printed side of the object fed to the printing press faces the printing press for printing after leaving the second collector.

12. The method according to claim 9 or 10, wherein - The first section of the conveying path transports the objects continuously at a number of workpieces per unit time which is at least twice the number of workpieces per unit time at which the inlet conveyor conveys the objects continuously or intermittently; - A buffer store between the inlet conveyor and the first section of the conveying path inputs the objects fed by the inlet conveyor into the first section of the conveying path as successive groups of objects which are spaced apart from one another, or the buffer store inputs the objects into the first section (1A) as individually spaced apart and / or inverted objects (K).

13. The method according to claim 9 or 10, wherein - The first section of the conveying path feeds the objects upstream of the printing press to a cleaning station and / or an input inspection station, and / or feeds the objects downstream of the printing press to a drying station and / or an output inspection station.

14. The method according to claim 9 or 10, wherein - The grippers of the stack conveyor grip and remove the stack of objects in the first collector and place and release them in the second collector, and / or wherein - A read / write device writes information along the conveying path into a magnetic strip arranged on the object, into an integrated circuit embedded in the object, wherein the read / write device performs the writing of the information either individually for each object or as a collective entry.

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