Method and device for printing on both sides of printing media

Abstract

The invention relates to a device for printing on printing media, having a transport device with a first receiving location and a second receiving location, said transport device being conveyable back and forth along a conveying path between a first and a second position; a printer on the conveying path, said printer being capable of printing on a first or a second side of one or more printing media located on the transport device when the transport device passes by the printer; an insert conveyor for the printing media, said insert conveyor feeding one of the printing media to the first receiving location when the first receiving location is in the first position; a discharge conveyor for discharging the printing media from the second receiving location when the second receiving location is in the second position; and a turning device close to the first or the second position for receiving the printing medium located at the first receiving location of the transport device, turning the received printing medium, and depositing the turned printing medium on the second receiving location of the transport device.

Description

[0001] Method and device for single- or double-sided printing of print media

[0002] Description

[0003] This discloses a method and device for single- or double-sided printing on print media. Details are defined in the claims; however, the description also contains relevant information on the structure and mode of operation, as well as variants of the method and device components.

[0004] background

[0005] Print media of the type discussed here are, in particular, flat objects in the form of security or identification documents such as ID cards, credit cards, bank cards, cash payment cards, labels, access badges, so-called holder pages of passports, identity cards, driver's licenses, and the like. These print media are at least partially flexible, elastic, and made of paper, plastic, metal, wood, or the like. These print media contain alphanumeric or graphic information on one or both sides. One variant of the print media of the type discussed here are identification cards in the so-called ID-1, ID-2, or ID-3 format, as defined in the ISO 7810 standard "Identification Cards - Physical Characteristics." The ID-1 card is widely used as a card in payment transactions.

[0006] Print media of the type discussed here can also be designed as magnetic stripe cards. These allow digital encoding of the data printed on the card or other data on a magnetic stripe located on the back of the card.

[0007] Print media of the type discussed here can also be designed as chip cards, which contain an integrated circuit in the card body with elements for data transmission, storage, and processing. Data can be transferred via contacts on the surface of the card or contactlessly using electromagnetic fields. Contactless chip cards avoid problems caused by contamination or wear of the contacts, or electrostatic discharges.

[0008] Items of the type presented here that are used as security or identification documents are generally manufactured centrally in their raw form, i.e., without personalization data, and then personalized in a decentralized manner, for example, at registration offices, government agencies, or companies authorized to issue such documents. During personalization, personalization data that individually identifies the respective holder of the security or identification document in the form of text, numerical, and / or image data (e.g., the holder's name and address, date of birth, place of birth, photo of the holder, biometric data of the holder, etc.), as well as the date of issue and period of validity of the document, are incorporated into the security or identification document. This text, numerical, and / or image data is at least partially directly readable by a viewer.The solution presented here is intended and used both for applying personalization data to the objects and for their basic design.

[0009] State of the art

[0010] To print on both sides of the media described here, it is possible to print on one side with a first printer, then turn it over, and print on the other side with a second printer. This solution is costly and space-intensive due to the two printers. Alternatively, the media described here is fed through a printer on an outward path and printed on one side, returned around the printer on a return path, turned over, fed through the same printer again on the outward path, and printed on the other side. This avoids the need for a second printer.

[0011] For example, US 2014 0 063 086 A1 discloses a card return path along which a plastic card, which has been fed through a printing station and printed on the first side, is diverted from a primary card movement path downstream of the printing station and returned to a primary card movement path at a location upstream of the printing station to be fed through the printing station again. A card that has been printed on its "A" side is diverted from the primary card movement path and drops into an output hopper. Each card is flipped over to its "B" side and returned to the input hopper for subsequent printing of the B side. Here, a plurality of the received plastic cards are recirculated through the printing station for reprinting using the card return path so that their second side can also be printed.This device is suitable for industrial mass production with a processing speed of several thousand (20,000 and more) cards per hour.

[0012] Document US 2014 0 182 768 A1 discloses the use of a smart card programming mechanism in production lines for manufacturing plastic cards with embedded chips. For this purpose, an encoder is provided upstream of a printing station, which personalizes or programs the chip embedded in a plastic card without contact. In the card processing system, the individual processing mechanisms are arranged downstream of the card feed. The card feed mechanism is arranged upstream of the card printing mechanism and upstream of the smart card programming mechanism, and the card output is arranged downstream of the card printing mechanism and downstream of the smart card programming mechanism.The card return movement path of the printing station intersects the primary card movement path at a first intersection point located downstream of the printing station and upstream of the card output, and at a second intersection point located downstream of the smart card programming mechanism and upstream of the printing station.

[0013] Printing, especially personalizing, such flat objects, especially cards, is usually done on both sides (front and back). However, single-sided printing is also often required. Labeling systems such as drop-on-demand (DoD) inkjet printers with single-pass printing processes are known, for example, from EP 3 130 646 B1. Such a single-pass printer has multiple print heads positioned in the conveying direction of the flat objects to be printed. Each print head, connected to an ink reservoir, has a plurality of print nozzles for printing a specific color (cyan, magenta, white, black, etc.). Each print head extends across the entire width of the flat objects, perpendicular to the conveying direction. With such printing systems, the flat objects cannot be stopped and turned under the print heads due to the lack of appropriately complex mechanics and control systems.The costs for the printing system components (printer, ink drying station, etc.) are high. For small and medium production volumes, double or multiple printing lines are not cost-effective. For two consecutively arranged marking systems for the front and back of such flat objects, a production system with a length / footprint that is not always available is required. Furthermore, the costs for this are not always economically justifiable.

[0014] In industrial production, it is necessary to print such media on one or both sides at high throughput. Such card processing systems can be designed for issuing relatively small quantities (10 or a few hundred per hour) as desktop processing machines, as disclosed in US patents US 7,434,728 B1 and US 7,398,972 B1, or for high-volume production (several hundred or thousand per hour) with multiple processing stations and modules, as described in US patents US 4,825,054 B1, US 5,266,781 B1, US 6,783,067 B1, and US 6,902,107 B1.

[0015] The arrangement described in US 2014 0 063 086 A1 or DE 2020 160 086 03 U1 feeds each card to the printing station along a primary card movement path and then returns each double-sided card individually to the printing station via the card return path. This has disadvantages. For example, the length of the card return path in relation to the speed of the double-sided cards along the card return path and their number on the return path (for single- and double-sided cards) influences the order of the cards at the exit of the printing station. In addition, the length of time each card spends in each of the numerous stations along the primary card movement path influences the printing process, making it more difficult to determine the order of the cards at the exit of the printing station.

[0016] US 20222 402 714 A1 discloses a device and method for treating multiple surfaces of objects. The device comprises a shuttle with at least two areas configured to receive objects. The shuttle is mounted such that it can move between two positions, passing through intermediate positions in which the shuttle presents a surface of the objects to a treatment device. A first handling device is configured to place an object in the first area when the shuttle is in the first position. A second handling device is configured to remove an object from the second area when the shuttle is in the second position. A third handling device is configured to remove the object in the first area, rotate it, and place the rotated object in the second area.

[0017] To avoid such disadvantages, a device and method for single- or double-sided printing of flat objects are disclosed here. The presented solution is advantageous for small and medium batch volumes, but also for higher throughputs.

[0018] Technological background is in the documents EP 0 580 280 Bl, US 2014 0 063 080 Al, EP 0 840 181 Bl, US 5,666,629 A, US 8 608 163 Bl, DE 30 49 607 Al, JP 2011 131 952 A, US 2014 10182 768 Al, US 6,783,067 B2, FR 2 827 807 Al, US 2009 0 152 790 Al, US 5 337 134 A, WO 93 04 433 Al, JP S58-167 347 A, US 6,308,886 Bl, DE 195 26 087 Al, EP 2 507 749 Bl, EP 2 018 973 Al, WO 2015 077 218 Al, US 2002 0 141 791 Al, JP 3 162 856 B2, DE 10 338 949 Al, WO 2004 065 124 A2, CN 204 414811 U, US 2014 0 063 086 Al, US 2001 0024228 Al, EP 835 739 A2, DE 3 236 884 Al, DE 3 704 059 Al, US 6,695,205 Bl, US 5,943,238 Bl, US 6,105,493 Bl, US 2013 / 0 220 984 Al and US 2020 122 490 A1. A company brochure from Atlantic Zeiser GmbH shows a device called "persomaster - EMV Banking Card Personalization System - First with DoD Inkjet Technology," September 29, 2015.

[0019] Solution

[0020] A method for single-sided or double-sided printing of print media comprises the following steps: a. Providing a transport device on a conveyor line, wherein the transport device has at least one first and at least one second receiving point for print media; wherein the first and second receiving points (22, 24) of the transport device (20) are designed to each fix a print medium (M) with the negative pressure available on their surfaces when the transport device (20) is conveyed back and forth along the conveyor line (40) between the first position (42) and the second position (44); b.Providing a printer on the conveyor line, and wherein the transport device is configured to be conveyed back and forth along the conveyor line between the first position upstream of the printer and the second position downstream of the printer such that when the printer passes, at least one print medium located on the transport device can be printed; c. Supplying the first receiving point of the transport device with a print medium when the transport device is in the first position on the conveyor line; d. Conveying the transport device along the conveyor line from the first to the second position, and printing the print medium located on the first receiving point of the transport device on its first side when the transport device passes the printer; e.Picking up the print medium located at the first pick-up point of the transport device from the transport device; f. Turning the picked-up print medium; and g. Placing the turned print medium on the second pick-up point of the transport device in such a way that the print medium placed on the second pick-up point of the transport device can be printed on its second side when the transport device passes the printer; h. Conveying the transport device with the print medium located at the first pick-up point of the transport device along the conveying path from the second position back to the first position; i. Feeding the first pick-up point of the transport device with another print medium; j.Conveying the transport device from the first to the second position, printing a first side of the print medium located at the first receiving position of the transport device, and printing a second side of the print medium located at the second receiving position of the transport device as the transport device passes the printer; and k. Removing the print medium located at the second receiving position of the transport device from the transport device.

[0021] For continuous operation, steps (e.) to (k.) are repeated. In the above variant, the printing medium is turned downstream of the printer. In the following variant, the printing medium is turned upstream of the printer.

[0022] Such a method for single-sided or double-sided printing of print media comprises the following steps: a. Providing a transport device on a conveyor line, wherein the transport device has at least one first and at least one second receiving point for a print medium; wherein the first and second receiving points (22, 24) of the transport device (20) are designed to each fix a print medium (M) with the negative pressure available on their surfaces when the transport device (20) is conveyed back and forth along the conveyor line (40) between the first position (42) and the second position (44); b.Providing a printer along the conveyor path, the transport device being configured to be conveyed back and forth along the conveyor path between the first position upstream of the printer and the second position downstream of the printer such that, as the printer passes, at least one print medium located on the transport device can be printed on; c. Supplying the first receiving point of the transport device with a print medium when the transport device is in the first position on the conveyor path; d. Conveying the transport device along the conveyor path from the first position to the printer, and printing the print medium located on the first receiving point of the transport device on its first side as the transport device passes the printer; e.Conveying the transport device with the print medium located at the first pick-up point of the transport device along the conveying path from the printer passed through back to the first position; f. Picking up the print medium located at the first pick-up point of the transport device from the transport device; g. Turning the picked-up print medium; and h. Placing the turned print medium on the second pick-up point of the transport device such that the print medium placed on the second pick-up point of the transport device can be printed on its second side when the transport device passes the printer; i. Feeding the first pick-up point of the transport device with another print medium; j.Conveying the transport device from the first to the second position, printing a first side of the print medium located at the first receiving position of the transport device, and printing a second side of the print medium located at the second receiving position of the transport device as the transport device passes the printer; and k. Removing the print medium located at the second receiving position of the transport device from the transport device;.

[0023] For continuous operation, steps (e.) to (k.) are repeated.

[0024] A device for single-sided or double-sided printing of print media, in particular according to one of the two above-mentioned procedures, is equipped with: a. a transport device, wherein the transport device has at least one first receiving location for a print medium and at least one second receiving location for a print medium; and wherein the transport device is configured to be conveyed back and forth along a conveying path between a first and a second position; b.a printer arranged on the conveyor line between the first and second positions, the printer being configured to print a first or a second side of one or more print media located at the first receiving point and / or the second receiving point of the transport device when the transport device is conveyed back and forth along the conveyor line between the first and second positions and passes the printer; c. an input conveyor for the print media, which is assigned to the conveyor line near the first position, and the input conveyor is configured to feed one of the print media to the first receiving point of the transport device when the transport device is in the first position; and d.an output conveyor for the print media, which is assigned to the conveyor line near the second position, and the output conveyor is configured to remove one of the print media from the second receiving point of the transport device when the transport device is in the second position; e. a turning device for the print media, which is assigned to the conveyor line near the first or second position, and the turning device is configured to.

[0025] - Picking up the print medium located at the first pick-up point of the transport device from the transport device; and / or

[0026] - Turning the recorded print medium; and / or

[0027] - depositing the turned print medium on the second receiving point of the transport device; and with f. a control device, set up and programmed to control the transport device and / or the conveyor line, the printer, the input conveyor, the output conveyor and / or the turning device; wherein the first and second receiving points (22, 24) of the transport device (20) are set up to each fix a print medium (M) with the negative pressure available on their surfaces when the transport device (20) is conveyed back and forth along the conveyor line (40) between the first position (42) and the second position (44).

[0028] There are several options for printing a card on either the front or back. For example, if the card is placed with its front side facing the first pickup point of the transport device, the card can be ejected for printing on the front side after the first pass through the printer. If only the back side is to be printed, the card passes through the printer with its front side facing up but is not printed on. Only after being turned over is it printed on the second pass and then ejected. For the variant with the card being turned upstream of the printer, the process must be adapted accordingly.

[0029] In one variant of the device, the transport device has several first receiving points for print media and several second receiving points for print media. The first and second receiving points can be arranged adjacent to each other. In one variant, the first and second receiving points are each arranged transversely to the conveying direction, so that—depending on the direction in which the transport device is conveyed—either the first or the second receiving points pass the printer first at the same time.

[0030] In one variant, the first and second receiving points of the transport device are designed to fix a pressure medium each with a controlled negative pressure available on their surfaces when the transport device is conveyed back and forth along the conveying path between the first and the second position.

[0031] In one variant, the conveyor line is designed as a circulating conveyor belt which is configured to convey the transport device back and forth; or as a drive belt to which the transport device is connected; or the transport device is configured to be conveyed back and forth along the conveyor line by a spindle / nut drive.

[0032] In one variant, the printer on the conveyor line for printing one side of the print medium is configured as an inkjet printer, a DoD printer, a transfer printer, or the like. In one variant, a device for coating the print medium over the printed image is provided, which device is configured as an inkjet printer, a DoD printer, a transfer printer, or the like. The device disclosed here can be implemented in different configurations; the two variants, in which the turning occurs either upstream or downstream of the printer, have already been mentioned.

[0033] In other variants, a device for cleaning the pressure medium is located on the conveyor line. This cleaning of the pressure medium can be done using compressed air, brushes, or similar devices, before or after the transport device is fed with the pressure medium.

[0034] In further variants, a device for feeding the transport device with the print medium is provided. This feeding of the transport device with the print medium can be done via a controlled-opening magazine, from which the print media are dispensed individually and deposited onto the transport device. This feeding of the transport device with the print medium can also be done via a conveyor belt, with which the print media is conveyed in a timed manner from a previous processing stage and deposited individually onto the transport device.

[0035] In further variants, a device for aligning the printing medium on the transport device in and / or transverse to the conveying direction is located on the conveyor line. This alignment of the printing medium can be achieved – for example, when the vacuum is switched off at the surfaces of the first and second receiving points of the transport device – by controlled slides that laterally engage the respective printing medium, or by angles that engage in two diagonal corners of the printing medium and position the respective printing medium.

[0036] In other variants, a device for plasma treatment of the printing medium is located on the conveyor line. This plasma treatment of the printing medium can take place before or after the alignment of the printing medium, and before printing.

[0037] In other variants, a device for drying the printed image is provided. This drying (pinning) of the printed image naturally occurs after the transport device has conveyed the respective print medium through the printer and one of the two sides of the print medium has been coated with a print image. This device for drying the printed image is located on the conveyor line upstream of the device for coating the print medium.

[0038] In further variants, a device for drying the printed image and the coating is located on the conveyor line downstream of the device for coating the printing medium above the printed image. This device for drying the printed image and the coating is tailored to the ink layer of the printed image and the (varnish) material of the coating of the printing medium. In one variant, the drying device is designed as a UV lamp, provided that the ink of the printed image and the coating material are curable by UV light.

[0039] In further variants, the printer is in particular a single-pass inkjet printer which has a plurality of print heads for ultraviolet (UV) curable ink arranged one behind the other in the conveying direction of the print media to be printed, and comprises one or more reservoirs with an ultraviolet (UV) curable ink of different colors.

[0040] In other variants, a device for turning the printing medium is located on the conveyor line either upstream or downstream of the printer. This turning of the printing medium can be achieved using grippers, suction lifters, or similar devices.

[0041] In further variants, a device for removing the printing medium located at the second receiving point of the transport device is located on the conveyor line downstream of the drying device. This device for removing the printing medium from the transport device serves to forward the printing medium to a subsequent processing stage.

[0042] In further variants, a device for an inlet inspection is located on the conveyor line downstream or upstream of the device for feeding the transport device with the pressure medium or the cleaning device. In further variants, a device for an outlet inspection is located on the conveyor line downstream of the drying device.

[0043] The solution presented here avoids unnecessary transport distances during continuous operation due to the at least two pick-up points (at least one first and at least one second pick-up point) of the transport device when printing on both sides of the print media. A transport device with only one pick-up point must pass through the transport path through the printer (back and forth) four times to output a double-sided printed card and return to its starting position. The solution presented here, with a transport device with two pick-up points, produces 1.5 cards in steady-state operation (as soon as both pick-up points are loaded with print media) with the same number of movements.

[0044] The alignment process is similar. With a transport setup with two pick-up points, two print media are aligned on both sides in three alignment processes. These savings compensate for disadvantages such as a slightly longer transport time due to a longer transport setup.

[0045] It should be understood that the solution presented here is also suitable for single-sided printing of print media. For this purpose, the print media is turned over after printing (pre-drying, coating, drying), turned in the second position onto the second pick-up point of the transport device, and then immediately removed from the transport device in the second position.

[0046] Short description of the drawing

[0047] Further objects, features, advantages, and possible applications will become apparent from the following description of non-limiting embodiments and the accompanying drawings. All described and / or illustrated features, individually or in any combination, constitute the subject matter disclosed herein, regardless of their grouping in the claims or their dependencies. Possible modifications will also become apparent to a person skilled in the art from the following description, which refers to the accompanying drawings. The figures schematically show variants of the device and method discussed herein.

[0048] Fig. 1 schematically illustrates an embodiment of a device for single-sided or double-sided printing of a plurality of print media.

[0049] Fig. 1a - Fig. 1g schematically illustrate the process of double-sided printing of a plurality of print media in a first variant.

[0050] Fig. 2a - Fig. 2g schematically illustrate the process of double-sided printing of a plurality of print media in a second variant.

[0051] Detailed description of the drawing

[0052] Fig. 1 shows a device 10 for single-sided or double-sided printing on a plurality of print media M. In the illustration shown, the print media M are implemented as identification (ID) cards made of plastic. The device 10 has a transport device 20 which transports the print media M on a rectilinear conveyor line 40. The conveyor line 40 conveys the print media M located on the transport device 20 as individual objects. In one variant, the conveyor line 40 is a circulating or belt conveyor in which one or more endless conveyor belts are guided over one or more driven and non-driven rollers. In the variant illustrated here, a rail conveyor is provided as the transport device 20, which can be moved in a controlled manner along a transport rail and transports one or more print media M.In the illustrated variant, the transport device 20 has a first receiving point 22 for a printing medium M and a second receiving point 24 for a printing medium M, wherein the receiving points 22, 24 are arranged adjacent to one another. The two receiving points 22, 24 are arranged one behind the other in the longitudinal direction of the conveying path 40. The transport device 20 is configured to be conveyed back and forth along the conveying path 40 between a first position 42 (left in Fig. 1) and a second position 44 (right in Fig. 1). In variants not further illustrated here, the transport device 20 has a plurality of first receiving points 22 and a plurality of second receiving points 24 for print media M. For example, two or more first receiving points 22 arranged next to one another and an equal number (two or more) second receiving points 24 arranged next to one another for print media M can be realized.In these variants, too, the first pick-up points 22 and the second pick-up points 24 are arranged one behind the other in the longitudinal direction of the conveyor line 40.

[0053] The first and second receiving points 22, 24 of the transport device 20 have openings on their surfaces receiving the print media M, at which controlled (switchable on / off) negative pressure is available to fix a print medium M in each case. This ensures that the print media M do not change their position and orientation when the transport device 20 is conveyed back and forth along the conveyor path 40 between the first position 42 and the second position 44.

[0054] The conveyor line 40 has an infeed conveyor 40a for the print media M on an inflow side (left in Fig. 1). The infeed conveyor 40a serves to individually apply the unprinted print media M upstream of a printer 30 in the first position 42 to the first receiving point(s) 22 of the transport device 20.

[0055] The conveyor line 40 has on a downstream side (in Fig. 1 on the right) a discharge conveyor 40b for the print media M. The discharge conveyor 40b serves to individually pick up and transport away the printed print media M downstream of the printer 30 in the second position 44 from the second pick-up point(s) 24 of the transport device 20.

[0056] The conveyor line 40 conveys the print media M located on the transport device 20 as individual items or in groups in a general conveying direction F from the input conveyor 40a to the output conveyor 40b. The print media M are printed between these two conveyors.

[0057] In the variant illustrated here, the printing media M is cleaned 50 before being transferred from the input conveyor 40a to the conveyor line 40.

[0058] In a further variant, not illustrated in detail here, the cleaning 50 of the printing media M takes place after they have been individually applied by the input conveyor 40a to the conveyor line 40, more precisely to the first receiving point(s) 22 of the transport device 20.

[0059] After the individual printing media M have been applied to the first receiving point(s) 22 of the transport device 20, the printing medium M is aligned 70 on the transport device 20 in and / or transversely to the conveying direction of the printing media M, as indicated by the directional arrows on the alignment device 70. Two grippers are used for this purpose, which, with the vacuum released, position the printing medium M correctly on the surface of the first receiving point 22. The vacuum on the surface of the first receiving point 22 is then activated, so that the printing medium M does not slip on the receiving point 22 during transport by the transport device 20.

[0060] Subsequently, the transport device 20 with the printing medium M held on the first receiving point 22 passes a device for plasma treatment 60 of the printing medium M. This serves to further clean the printing medium M before it is printed.

[0061] Next, the transport device 20 with the print medium M held on the first receiving point 22 and / or on the second receiving point 24 passes a printer 30 for printing the upper side of the respective print medium M. In this variant, this printer 30 is designed as a DoD printer (drop on demand), as an inkjet printer, as a transfer printer or the like.

[0062] This is followed by a device 80 for drying the printed image, which next passes the transport device 20 with the print medium M held on the first receiving point 22 and / or the print medium M held on the second receiving point 24.

[0063] The transport device 20, with the print medium M held at the first receiving location 22 and / or the print medium M held at the second receiving location 24, next passes a device 90 for coating the print medium M over the printed image. This device 90 for coating the print medium M over the printed image is also designed as an inkjet printer, a DoD printer, a transfer printer, or the like.

[0064] Next, the transport device 20, with the print medium M held at the first receiving location 22 and / or the print medium M held at the second receiving location 24, moves through a device for (through-)drying 100 of the printed image and the coating. If the printer 30 dispenses ultraviolet (UV)-curable printing ink or printing ink, and the coating varnish of the printed image is also ultraviolet (UV)-curable, the device for (through-)drying 100 of the printed image and the coating has a UV light source. The transport device 20, with the print medium M held at the first receiving location 22, is then moved to a device for turning the print medium M.Here, the print medium M located on the first pick-up point 22 of the transport device 20 is picked up by the transport device 20, the picked-up print medium M is turned over, and the turned-over print medium M is placed on the second pick-up point 24 of the transport device 20. Subsequently, the vacuum on the surface of the second pick-up point 24 is activated so that the print medium M does not slip on the second pick-up point 24 during transport by the transport device 20.

[0065] Downstream of the turning device 110 is the discharge conveyor 40b for the print media M. The discharge conveyor 40b serves to individually pick up the printed print media M downstream of the printer 30 in the second position 44 from the second pick-up point(s) 24 of the transport device 20 and to transport them away for further processing of the print media M. The discharge conveyor 40b for the print media M is assigned to the conveyor line 40 near the second position (44). The discharge conveyor 40b is configured to remove one of the print media M from the second pick-up point(s) 24 of the transport device 20 when the transport device 20 is in the second position 44.

[0066] Figs. 1a - 1g illustrate a process for double-sided printing on print media M. Only the insertion, printing, turning, and ejection of the print media M are illustrated. The drying, coating, and drying of the print image and the coating are omitted here for clarity. The process comprises the following steps:

[0067] Step a. (Fig. 1a) includes providing a transport device 20 on a conveyor line 40. The transport device 20 has at least one first receiving location 22 for a printing medium M and at least one second receiving location 24 for a printing medium M.

[0068] Step b. (Fig. 1a) includes providing a printer 30 on the conveyor line 40 for the transport device 20. The transport device 20 is configured to be conveyed back and forth along the conveyor line 40 between a first position 42 upstream of the printer 30 and a second position 44 downstream of the printer 30 such that, upon passing the printer 30, at least one print medium M located on the transport device 20 can be printed.

[0069] As soon as a print medium M is located on the first and / or second receiving point 22, 24 on the transport device 20, the vacuum on the surface of the respective receiving point 22, 24 is activated so that the print medium M does not slip on the respective receiving point 22, 24 during transport through the transport device 20.

[0070] Step c. (Fig. la) includes feeding the first receiving point 22 of the transport device 20 with a pressure medium M by means of the input conveyor when the transport device 20 is in the first position 42 on the conveyor line 40.

[0071] Step d. (Fig. 1b) includes conveying the transport device 20 along the conveying path 40 from the first position 42 to the second position 44, and printing the print medium M located on the first receiving point 22 of the transport device 20 on its first side IS as the transport device 20 passes the printer.

[0072] Step e. (Fig. lc) includes picking up the print medium M located on the first pick-up point 24 of the transport device 20 from the transport device 20 when the transport device 20 is located in the second position 44 on the conveyor line 40.

[0073] Step f. (Fig. lc) includes turning the received printing medium M when the transport device 20 is in the second position 44 on the conveyor line 40.

[0074] Step g. (Fig. lc) includes depositing the turned print medium M on the second receiving point 24 of the transport device 20 when the transport device 20 is located on the conveyor path 40 in the second position 44 such that the print medium M deposited on the second receiving point 24 of the transport device 20 can be printed on its second side 2S when the transport device 20 next passes the printer 30 in the conveying direction.

[0075] Step h. (Fig. 1d) involves conveying the transport device 20 with the print medium M located at the second receiving point 24 of the transport device 20 along the conveying path 40 from the second position 44 back to the first position 42. As mentioned, the second side 2S of the print medium M deposited on the second receiving point 24 of the transport device 20 is not yet printed.

[0076] Step i. (Fig. 1e) includes feeding the first receiving point 22 of the transport device 20 with a further pressure medium M when the transport device 20 is in the first position 42 on the conveyor line 40.

[0077] Step j. (Fig. 1f) includes conveying the transport device 20 from the first position 42 to the second position 44, printing a first side IS of the print medium M located at the first receiving position 22 of the transport device 20 and printing a second side IS of the print medium M located at the second receiving position 24 of the transport device 20 when the transport device 20 passes the printer 30 in the conveying direction.

[0078] Step k. (Fig. 1g) includes removing the print medium M located at the second receiving point 24 of the transport device 20 from the transport device 20 when the transport device 20 is located in the second position 44 on the conveyor line 40.

[0079] In continuous operation, steps e. to k. are subsequently repeated continuously as shown in Figs. lc to lg.

[0080] Figs. 2a - 2g illustrate an alternative method for double-sided printing on print media M. Only the insertion, printing, turning, and ejection of the print media M are illustrated. The drying, coating, and drying of the printed image and the coating are omitted here for clarity. These steps are explained in more detail in connection with the description of the device and Fig. 1. The method comprises the following steps:

[0081] Step a. (Fig. 2a) includes providing a transport device 20, wherein the transport device 20 has at least one first receiving location 22 for a print medium M and at least one second receiving location 24 for a print medium M.

[0082] Step b. (Fig. 2a) includes providing a printer 30 along a conveyor path 40 for the transport device 20, wherein the transport device 20 is configured to be conveyed back and forth along the conveyor path 40 between a first position 42 upstream of the printer 30 and a second position 44 downstream of the printer 30 such that, upon passing the printer 30, at least one print medium M located on the transport device 20 can be printed.

[0083] Step c. (Fig. 2a) includes feeding the first receiving point 22 of the transport device 20 with a pressure medium M when the transport device 20 is in the first position 42 on the conveyor line 40.

[0084] As soon as a print medium M is located on the first and / or second receiving point 22, 24 on the transport device 20, the vacuum on the surface of the respective receiving point 22, 24 is activated so that the print medium M does not slip on the respective receiving point 22, 24 during transport through the transport device 20.

[0085] Step d. (Fig. 2b) includes conveying the transport device 20 along the conveying path 40 from the first position 42 to the printer 30, and printing the print medium M located at the first receiving location 22 of the transport device 20 on its first side IS as the transport device 20 passes the printer 30.

[0086] Step e. (Fig. 2c) Conveying the transport device 20 with the print medium M located at the first receiving point 22 of the transport device 20 along the conveying path 40 from the printer 30 back to the first position 42.

[0087] Step f. (Fig. 2d) includes picking up the print medium M located at the first pick-up point 22 of the transport device 20 from the transport device 20 when the transport device 20 is located in the first position 42 on the conveyor line 40.

[0088] Step g. (Fig. 2d) involves turning the received print medium M when the transport device 20 is in the first position 42 on the conveyor line 40.

[0089] Step h. (Fig. 2d) includes depositing the turned print medium M at the second receiving point 24 of the transport device 20 when the transport device 20 is located in the first position 42 on the conveyor line 40, such that the print medium M deposited on the second receiving point 24 of the transport device 20 can be printed on its second side 2S when the transport device 20 passes the printer 30.

[0090] Step i. (Fig. 2e) includes feeding the first receiving point 22 of the transport device 20 with another printing medium M when the transport device 20 is in the first position 42 on the conveyor line 40.

[0091] Step j. (Fig. 2f) includes conveying the transport device 20 from the first position 42 to the second position 44, printing a first side IS of the print medium M located at the first receiving position 22 of the transport device 20 and printing a second side 2S of the print medium M located at the second receiving position 24 of the transport device 20 when the transport device 20 passes the printer 30 in the conveying direction from the first position 42 to the second position 44.

[0092] Step k. (Fig. 2g) includes removing the print medium M located at the second receiving point 24 of the transport device 20 from the transport device 20 when the transport device 20 is located in the second position 44 on the conveyor line 40.

[0093] In continuous operation, steps e. to k. are then continuously repeated according to Figs. 2d to 2g. The variants of the device described above, as well as their construction and operating aspects, serve only to improve understanding of the structure, mode of operation, and properties; they do not restrict the disclosure to the exemplary embodiments. The figures are partly schematic, with essential properties and effects sometimes shown significantly enlarged in order to clarify the functions, operating principles, technical designs, and features. Each mode of operation, each principle, each technical design, and each feature disclosed in the figures or in the text can be incorporated into all claims, each feature in the text, and in the other figures., other modes of operation, principles, technical embodiments and features contained in this disclosure or resulting therefrom can be freely and arbitrarily combined so that all conceivable combinations can be assigned to the described procedure. This also includes combinations between all individual embodiments in the text, i.e. in every section of the description, in the claims and also combinations between different variants in the text, in the claims and in the figures. The claims also do not limit the disclosure and thus the possible combinations of all the features shown with one another. All disclosed features are explicitly disclosed here, both individually and in combination with all other features.

Claims

Claims 1. A method for single-sided or double-sided printing of print media (M), comprising the following steps: a. Providing a transport device (20) on a conveyor line (40), wherein the transport device (20) has at least one first receiving point (22) for a print medium (M) and at least one second receiving point (24) for a print medium (M), wherein the first and second receiving points (22, 24) of the transport device (20) are designed to each fix a print medium (M) with negative pressure available on their surfaces when the transport device (20) is conveyed back and forth along the conveyor line (40) between a first position (42) and a second position (44); b.Providing a printer (30) along the conveyor path (40) for the transport device (20), wherein the transport device (20) is configured to be conveyed back and forth along the conveyor path (40) between the first position (42) upstream of the printer (30) and the second position (44) downstream of the printer (30) in such a way that, when passing the printer (30), at least one print medium (M) located on the transport device (20) can be printed; c. feeding the first receiving point (22) of the transport device (20) with a print medium (M) when the transport device (20) is in the first position (42) on the conveyor path (40); d.Conveying the transport device (20) along the conveying path (40) from the first position (42) to the second position (44), and printing the print medium (M) located at the first pick-up point (22) of the transport device (20) on its first side (IS) as the transport device (20) passes the printer; e. Picking up the print medium (M) located at the first pick-up point (22) of the transport device (20) from the transport device (20); f. Turning the picked-up print medium (M); and g. Placing the turned print medium (M) on the second pick-up point (24) of the transport device (20) in such a way that the print medium (M) located at the second pick-up point (24) of the transport device (20) deposited print medium (M) can be printed on its second side (2S) when the transport device (20) passes the printer (30); h. conveying the transport device (20) with the print medium (M) located at the second receiving point (24) of the transport device (20) along the conveying path (40) from the second position (44) back to the first position (42); i. feeding the first receiving point (22) of the transport device (20) with a further print medium (M); j. Conveying the transport device (20) from the first position (42) to the second position (44), printing a first side (IS) of the print medium (M) located at the first receiving point (22) of the transport device (20) and printing a second side (2S) of the print medium (M) located at the second receiving point (24) of the transport device (20) when the transport device (20) passes the printer (30); and k.Removing the print medium (M) located at the second receiving point (24) of the transport device (20) from the transport device (20); l. Repeating steps (e) to (k).

2. A method for single-sided or double-sided printing of print media (M), comprising the following steps: a. Providing a transport device (20) on a conveyor line (40), wherein the transport device (20) has at least one first receiving point (22) for a print medium (M) and at least one second receiving point (24) for a print medium (M), wherein the first and second receiving points (22, 24) of the transport device (20) are designed to each fix a print medium (M) with negative pressure available on their surfaces when the transport device (20) is conveyed back and forth along the conveyor line (40) between a first position (42) and a second position (44); b.Providing a printer (30) along the conveyor path (40) for the transport device (20), wherein the transport device (20) is designed to be conveyed back and forth along the conveyor path (40) between the first position (42) upstream of the printer (30) and the second position (44) downstream of the printer (30) in such a way that when passing the printer (30) at least one on the. transport device (20) can be printed on; c. feeding the first receiving point (22) of the transport device (20) with a print medium (M) when the transport device (20) is in the first position (42) on the conveyor path (40); d. conveying the transport device (20) along the conveyor path (40) from the first position (42) to the printer (30), and printing the print medium (M) located at the first receiving point (22) of the transport device (20) on its first side (IS) when the transport device (20) passes the printer (30); e. Conveying the transport device (20) with the pressure medium (M) located at the first receiving point (22) of the transport device (20) along the conveying path (40) from the second position (44) back to the first position (42); f.Picking up the print medium (M) located at the first pick-up point (22) of the transport device (20) from the transport device (20); g. Turning the picked-up print medium (M); and h. Depositing the turned print medium (M) at the second pick-up point (24) of the transport device (20) such that the print medium (M) deposited at the second pick-up point (24) of the transport device (20) can be printed on its second side (2S) when the transport device (20) passes the printer (30); i. Feeding the first pick-up point (22) of the transport device (20) with a further print medium (M); j.Conveying the transport device (20) from the first position (42) to the second position (44), printing a first side (IS) of the print medium (M) located at the first receiving point (22) of the transport device (20) and printing a second side (2S) of the print medium (M) located at the second receiving point (24) of the transport device (20) when the transport device (20) passes the printer (30); and k. Removing the print medium (M) located at the second receiving point (24) of the transport device (20) from the transport device (20); l. Repeating steps (e) to (k).

3. A device for single- or double-sided printing of print media (M), with a. a transport device (20), wherein the transport device (20) has at least one first receiving point (22) for a print medium (M) and at least one second receiving point (24) for a print medium (M); and wherein the transport device (20) is configured to be conveyed back and forth along a conveying path (40) between a first position (42) and a second position (44); b.a printer (30) arranged along the conveyor path (40) between the first position (42) and the second position (44), wherein the printer (30) is configured to print a first side (2S) or a second side (2S) of one or more print media (M) located at the first receiving point (22) and / or the second receiving point (24) of the conveyor device (20) when the conveyor device (20) is conveyed back and forth along the conveyor path (40) between the first position (42) and the second position (44) and in the process passes the printer (30); c. an input conveyor (40a) for the print media (M), which is assigned to the conveyor line (40) near the first position (42), and the input conveyor (40a) is configured to feed one of the print media (M) to the first receiving point (22) of the transport device (20) when the transport device (20) is in the first position (42); and d.a discharge conveyor (40b) for the print media (M), which is assigned to the conveyor line (40) near the second position (44), and the discharge conveyor (40b) is designed to remove one of the print media (M) from the second receiving point (24) of the transport device (20) when the transport device (20) is in the second position (44); e. a turning device (50) for the print media (M), which is assigned to the conveyor line (40) near the first position (42) or the second position (44), and the turning device (50) is designed to. - picking up the print medium (M) located on the first pick-up point (22) of the transport device (20) from the transport device (20); and / or - Turning the recorded print medium (M); and / or - depositing the turned printing medium (M) at the second receiving point (24) of the transport device (20); and with f. a control device (ECU) configured to control the transport device (20) and / or the conveyor line (40), the printer (30), the input conveyor (40a), the output conveyor (40b), and / or the turning device (50), and programmed to carry out the steps of the method according to claim 1 or 2; wherein the first and second receiving points (22, 24) of the transport device (20) are configured to each fix a printing medium (M) with the negative pressure available on their surfaces when the transport device (20) is conveyed back and forth along the conveyor line (40) between the first position (42) and the second position (44).

4. The device with the features according to claim 3, wherein the transport device (20) has a plurality of first receiving locations (22) for print media (M) and a plurality of second receiving locations (24) for print media (M).

5. The device having the features according to claim 0 or 4, wherein the first and second receiving locations (22, 24) are each arranged adjacent to one another.

6. The device with the features according to one of claims 3 to 5, wherein the conveyor line (40) is designed as a circulating conveyor belt which is configured to convey the transport device (20) back and forth; or as a drive belt to which the transport device (20) is connected; or the transport device (20) is configured to be conveyed back and forth along the conveyor line (40) by a spindle / nut drive.

7. The device with the features according to one of claims 3 to 6, wherein the printer (30) for printing (30) one side of the print medium (M) is configured as an inkjet printer, a DoD printer, a transfer printer, or the like; and / or a device for coating (90) the print medium (M) over the printed image is configured as an inkjet printer, a DoD printer, a transfer printer, or the like.

8. The device with the features according to one of claims 3 to 7, wherein a device for cleaning (50) the printing medium (M), and / or an input conveyor (40a) for feeding the transport device (20) with the printing medium (M), and / or a device for aligning (70) the printing medium (M) on the transport device (20) in and / or transversely to the conveying direction, and / or a device for plasma treatment (60) of the printing medium (M), and / or a device for drying (80) the printed print image, and / or a device for coating (90) the printing medium (M), and / or a device for (through-)drying (100) the printed print image and the coating, and / or a device for turning (110) the printing medium (M), and / or a discharge conveyor (40b) are provided for passing on the print medium (M) for subsequent processing.

Images