Control device and method for operating a printing apparatus when raised areas are present in the recording medium.
The control device for inkjet printing devices detects and manages raised portions on the recording carrier by pausing printing, widening the gap, and resuming operations, addressing damage prevention and efficiency issues.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- CANON PRODN PRINTING HLDG BV
- Filing Date
- 2022-01-27
- Publication Date
- 2026-06-29
Smart Images
Figure 0007881314000001 
Figure 0007881314000002 
Figure 0007881314000003
Abstract
Description
Technical Field
[0001] The present invention relates to a method of operating a printing device, particularly an inkjet printing device, when recognizing raised portions of a recording carrier to be printed, and a control device corresponding thereto.
[0002] An inkjet printing device for printing a recording carrier has at least one printing bar provided with one or more printing heads. In this case, each printing head typically has a large number of nozzles. Each nozzle is configured to discharge ink droplets so that pixels of a printed image can be printed on the recording carrier.
[0003] During a printing operation, a printing bar provided with one or more printing heads is typically arranged relatively close to the surface of the recording carrier to be printed, for example, within 2 mm, in order to enable the highest possible printing quality. Therefore, there is a risk that raised portions of the recording carrier, such as local adhesion points of the recording carrier, will cause contact between the surface of the recording carrier and the nozzle plate of the printing head of the printing device, which may lead to damage to the printing head.
[0004] This specification addresses the technical problem of protecting a printing device, particularly an inkjet printing device, efficiently and reliably from damage to raised portions of a recording carrier to be printed. This problem is solved by the features described in independent device claim 1. Furthermore, this problem is solved by the features described in independent method claim 10.
[0005] Based on one aspect of the present invention, a control device for controlling a printing device having at least one printing unit provided with at least one printing bar is described. The printing device is configured to cause relative movement between the printing unit and a recording carrier to be printed by the printing unit, thereby sequentially printing columns of a valid printed image on the recording carrier during a printing operation.
[0006] The control device is configured to detect the raised portion of the recording medium to be printed on and, in response to the detection of the raised portion, to pause the printing operation while relative movement between the printing unit and the recording medium continues. The control device may further be configured to widen the printing gap between the printing unit and the recording medium during the printing pause, for example by raising the printing unit, so that the detected raised portion of the recording medium can be guided through the printing unit within the frame of the continued relative movement. The control device is further configured to narrow the printing gap between the printing unit and the recording medium again after the detected raised portion of the recording medium has been guided through the printing unit, and to resume the printing operation after the printing gap between the printing unit and the recording medium has narrowed.
[0007] A method for controlling a printing apparatus having at least one printing unit equipped with at least one printing bar is described according to one aspect of the present invention. The printing apparatus is configured to cause relative movement between the printing unit and the recording medium to be printed by the printing unit, thereby sequentially printing a series of valid print images onto the recording medium during a printing operation.
[0008] The method includes the steps of detecting a raised portion of the recording medium to be printed, and, in response to the detection of the raised portion, continuing the relative movement between the printing unit and the recording medium while simultaneously pausing the printing operation of the printing unit. The method further includes the step of widening the printing gap between the printing unit and the recording medium during the printing pause, thereby guiding the detected raised portion of the recording medium through the printing unit within the frame of the continued relative movement, in particular, so that the raised portion does not come into contact with the printing unit. The method further includes the step of narrowing the printing gap between the printing unit and the recording medium again after the detected raised portion of the recording medium has been guided through the printing unit. The method further includes the step of restarting the printing operation of the printing unit after the printing gap between the printing unit and the recording medium has been narrowed.
[0009] The embodiments of the present invention will now be described in more detail based on the schematic diagram. [Brief explanation of the drawing]
[0010] [Figure 1] This is a diagram illustrating the configuration of an exemplary inkjet printing apparatus. [Figure 2a] This figure shows the different states of the print bar as it passes over the raised portion of the recording medium. [Figure 2b] This figure shows the different states of the print bar as it passes over the raised portion of the recording medium. [Figure 2c] This figure shows the different states of the print bar as it passes over the raised portion of the recording medium. [Figure 3] This figure shows an exemplary time chart for the operation of the printing apparatus when a raised portion of the recording medium is detected. [Figure 4] This diagram shows a flowchart illustrating an exemplary method for operating a printing device in response to the recognition of raised areas on a recording medium.
[0011] The printing apparatus 100 shown in Figure 1 is designed for printing on a strip-shaped, web-shaped, sheet-shaped, or single-fed recording carrier 120. The printing apparatus 100 may optionally be configured to feed the web-shaped recording carrier 120 from rollers. The recording carrier 120 may be made from paper, cardboard, thick paper, metal, plastic, fiber, a combination thereof, and / or other suitable printable material. The recording carrier 120 is transported through at least one printing unit 141, 142 of the printing apparatus 100 along the transport direction 1 indicated by the arrow.
[0012] The printing units 141 and 142 of the printing apparatus 100 have two print bars 102 in the illustrated embodiment, in which case each print bar 102 may be used to print using inks of a predetermined color, such as black, cyan, magenta and / or yellow and optionally MICR ink. Furthermore, the printing apparatus 100 has at least one fixing unit or drying unit (not shown) configured to fix the printed image printed on the recording carrier 120.
[0013] The print bar 102 may have one or more print heads 103, which may be arranged in multiple rows side by side, thereby enabling the printing of pixels from different rows 31, 32 of a single print image onto the recording medium 120. In the example shown in Figure 1, the print bar 102 has five print heads 103, in which case each print head 103 prints a group of pixels from rows 31, 32 of the print image onto the recording medium 120.
[0014] Each print head 103 of the print units 141, 142 has a plurality of nozzles 21, 22 in the embodiment shown in Figure 1, in which case each nozzle 21, 22 is configured to fire or discharge ink droplets onto the recording medium 120. One print head 103 of the print units 141, 142 may have, for example, thousands of effectively used nozzles 21, 22, which are arranged along a plurality of rows laterally with respect to the transport direction 1 of the recording medium 120. Through the nozzles 21, 22 of one print head 103 of one print unit 141, 142, a row of pixels of a print image can be printed on the recording medium 120 laterally with respect to the transport direction 1, i.e., along the width of the recording medium 120.
[0015] The printing apparatus 100 further includes a control unit or control device 101, such as control hardware and / or a controller, configured to control the actuators of individual nozzles 21, 22 of individual print heads 103 of one or more printing units 141, 142, thereby allowing the printed image to be deposited onto the recording carrier 120 according to the print data.
[0016] In other words, the printing units 141,142 of the printing device 100 have at least one printing bar 102 with K nozzles 21,22 that can be controlled in a predetermined column cycle, thereby printing a column extending laterally with respect to the transport direction 1 of the recording carrier 120 onto the recording carrier 120 with K pixels or K rows 31,32 of a printed image (e.g., K>1000). The nozzles 21,22 are fixedly or immovably mounted within the printing device 100 in the illustrated example, and the recording carrier 120 is guided by passing alongside the stationary nozzles 21,22 at a predetermined transport speed.
[0017] Furthermore, the printing apparatus 100 may have one or more regeneration units 150 for one or more print bars 102 corresponding to one or more print units 141, 142. The print bars 102 may be moved from a printing position where the print bar 102 is positioned on the recording medium 120 to a cleaning position or a maintenance position. For this purpose, the print bar 102 may be moved in the direction of movement 2 indicated by the arrow. Then, the nozzle plates of one or more print heads 103 of one print bar 102 may be cleaned, for example, wiped, by the regeneration unit 150 in the cleaning position or maintenance position. Furthermore, the regeneration unit 150 may also clean one or more print heads 103 that are covered with ink. The printing apparatus 100 may have at least one or only one regeneration unit 150 for each print bar 102.
[0018] In the example shown in Figure 1, the printing apparatus 100 has two printing units 141 and 142, which may be identical in structure, and these printing units 141 and 142 can be used, for example, to print on the front and back sides of the recording medium 120. Between the two printing units 141 and 142, a reversing unit 160 formed to turn the recording medium 120 inside out may be positioned, so that the front side of the recording medium 120 can be printed by the first printing unit 141 and the back side of the recording medium 120 can be printed by the second printing unit 142.
[0019] As mentioned at the beginning, the recording carrier 120 may have obstacles such as adhesive points, butt joints, folded edges, or other deformations. The printing gap between the printable surface of the recording carrier 120 and the nozzle plate of one or more print heads 103 of the printing apparatus 100 is typically relatively small, for example, less than 2 mm, in order to achieve the highest possible print quality. Therefore, there is a risk that a defective area or obstacle on the recording carrier 120 may come into contact with the nozzle plate of the print head 103 and potentially be damaged.
[0020] The printing device 100 may have a sensor unit 110 configured to detect raised portions of the recording medium 120 to be printed. The sensor unit 110 may be located upstream of the first printing unit 141 relative to the transport direction 1 of the recording medium 120. The control unit 101 of the printing device 100 may be configured to immediately interrupt the ongoing printing operation when a raised portion of the recording medium 120 is recognized based on sensor data from the sensor unit 110. The recognized raised portion of the recording medium 120 may then be guided through the first printing unit 141 and any second printing unit 142 without the recording medium 120 being printed. Furthermore, as soon as the recognized raised portion of the recording medium 120 has passed through one or more printing units 141, 142 of the printing device 100, the user of the printing device 100 can manually restart the printing operation.
[0021] The above-described reaction of the printing apparatus 100 with respect to the recognized raised portions of the recording carrier 120 causes relatively large labor and / or relatively much waste paper that must be removed for the user of the printing apparatus 100. Further, when restarting the printing operation, typically cleaning of one or more print heads 103 in one or more reproducing units 150, particularly cleaning of one or more print heads 103, is required, which is associated with relatively large ink consumption and additional time waste.
[0022] One or more print bars 102, particularly one or more print heads 103, may be formed such that each individual print bar 102 is movable perpendicular to the surface of the recording carrier 120, whereby the distance or printing gap between each print bar 102 and the surface of the recording carrier 120 can be increased. This is illustrated by the arrows in FIGS. 2a to 2c.
[0023] The control unit or control device 101 of the printing apparatus 100 may be configured to raise the individual print bars 102 of the printing units 141, 142 in response to recognition of the raised portions 210 of the recording carrier 120 to be printed. In this case, first, the print bar 102 located closest to the raised portion 210 may be moved, and then, as illustrated in FIG. 2b, subsequent print bars 102 may be sequentially raised.
[0024] After the raised portion 210 has passed through one print bar 102, this print bar 102 may be lowered again, whereby, as illustrated in FIG. 2c, the print bars 102 of the printing units 141, 142 are sequentially lowered again. By the sequential raising and / or lowering of the print bars 102, the raising or lowering of the print bars 102 can be caused particularly energy-efficiently and in a timely manner. This makes it possible to shorten the duration of the printing pause.
[0025] Figure 3 shows an exemplary time chart for operating the printing device 100 in response to the recognized raised portion 210. The raised portion 210 is recognized at the detection time point 311. In response to this detection, a printing pause signal 303 may be set by the control device 101. The printing pause signal 303 has a predetermined time length 333 indicating the duration for which the printing operations of the printing units 141, 142 should be paused based on the recognized raised portion 210.
[0026] Figure 3 further shows the conveying speed 304 of the recording carrier 120 based on the raised portion 210 recognized at the detection time point 311. The conveying speed 304 cannot be reduced (at least in the first step). In other words, the recording carrier 120 continues to move within the printing device 100 unchanged after the recognition of the raised portion 210.
[0027] As can be seen from FIG. 1, the first printing unit 141 has a first spatial distance 131 from the sensor unit 110 that recognizes the raised portion 210, and any second printing unit 142 has a second spatial distance 132. The spatial distances 131, 132 correspond to the time intervals 331, 332 between the sensor unit 110 and each of the printing units 141, 142 according to the conveying speed 304 of the recording carrier 120. In particular, the time intervals 331, 332 may be proportional to the spatial distances 131, 132, and in this case, the proportionality constant depends on the conveying speed 304 and in particular corresponds to the conveying speed 304.
[0028] Figure 3 shows a first control signal 301 for the first printing unit 141 and a second control signal 302 for any second printing unit 142. The first control signal 301 may be shifted in time by a first time interval 331 with respect to the printing pause signal 303 and may indicate the time for which the first printing unit 141 performs printing pause. Similarly, the second control signal 302 may be shifted in time by a second time interval 332 with respect to the printing pause signal 303 and may indicate the time for which the second printing unit 142 performs printing pause.
[0029] Figure 3 shows the start time 312 when the first printing unit 141 begins to pause printing, and the end time 313 when the first printing unit 141 ends to pause printing. Furthermore, Figure 3 shows the start time 314 when the second printing unit 142 begins to pause printing, and the end time 315 when the second printing unit 142 ends to pause printing.
[0030] During each printing pause, one or more print bars 102 of each printing unit 141, 142 may first move away from the surface of the recording medium 120, pass over the raised portion 210, and then move toward the surface of the recording medium 120 again, as shown in Figures 2a to 2c. This ensures that contact between the raised portion 210 of the recording medium 120 and the nozzle plates of each print head 103 provided on one or more print bars 102 is prevented.
[0031] As can be seen from Figure 3, the printing pause for individual printing units 141 and 142 is time-limited. Following the printing pause, printing can be resumed, particularly from where the interruption occurred. For example, the printing pause may begin immediately after printing a specific page x of the valid print image to be printed. After the printing pause ends, printing can resume from the page x+1 immediately following the valid print image.
[0032] In the time chart shown at the bottom of Figure 3, the printing pause has a time duration 333 that allows the printing pause to be terminated again after the recognized raised portion 210 has been guided completely through the first printing unit 141 and the second printing unit 142. This control of the printing apparatus 100 can be efficiently implemented by the control device 101 of the printing apparatus 100.
[0033] In the time chart shown at the top of Figure 3, the print pause has a time length 333 that allows the print pause to be terminated again after the recognized raised portion 210 has been guided through only one of the print units 141, 142. In this case, the print pause for each print unit 141, 142 may be terminated again as soon as the raised portion 210 passes through each print unit 141, 142. In other words, the print pause for print units 141, 142 can be limited to the time length required for the raised portion 210 to pass through each print unit 141, 142. In this way, particularly short print pauses can be made, thereby significantly reducing the impact of the recognized raised portion 210 of the recording carrier 120, particularly on waste and / or print efficiency.
[0034] The effective print image to be printed by the printing device 100 may be divided into page order. Individual pages may be identified, for example, by an index x. The control device 101 may be configured such that the print pause of the printing units 141 and 142, i.e., the control signals 301 and 302 for the printing units 141 and 142, are timely arranged in accordance with the print pause signal 303, so that the print pause begins immediately after the printing of an entire page x, and immediately after the print pause ends, printing of the next page x+1 can begin. In other words, the print pause can be timely arranged so that no incomplete pages are printed on the recording medium 120 immediately before the print pause, and / or only fully printed pages are printed on the recording medium 120. In this way, print pauses for the recognized raised portion 210 can be made particularly resource-efficient.
[0035] In other words, the length of the time intervals 331, 332 and / or the print pause or corresponding control signals 301, 302 is • Conveying speed of the recording carrier 120: 304 • The spatial distance 131, 132 between the sensor unit 110 and each printing unit 141, 142, and / or • Arrangement of individual pages x in the valid print image to be printed It can be calculated depending on [the following].
[0036] For example, the time interval 331,332T is expressed in a mathematical formula. T = D / v - Δ It can be calculated based on the following, in which case D is the spatial distance 131,132 and v is the transport speed 304. Δ is a temporal offset resulting from the fact that the printing pause begins after the completion of page x, which has already been fully printed, and not at the last possible point in time when there is an unfinished page x+1.
[0037] Similarly, the length Q of the print pause or control signal 301,302 is given by the following formula: Q = R + Δ It can be calculated based on the following, in which case R is the length of time required for the raised portion 210 to pass through one printing unit 141,142 (the case shown at the top of Figure 3) or to pass through two printing units 141,142 (the case shown at the bottom of Figure 3).
[0038] The control device 101 may be configured to cause the printing units 141, 142 to print a subsequent print image using one or more subsequent pages after the completion of printing page x of the print image and before the start of a print pause. Alternatively or supplementarily, the control device 101 may be configured to cause the printing units 141, 142 to print a preceding print image using one or more preceding pages after the end of a print pause and before the printing of page x+1 of the print image. One or more subsequent pages and / or one or more preceding pages may be used by a post-processing unit of the printing device 100, for example, a cutting unit that cuts individual printed pages of the valid print image, to synchronize the printing device 100 with the interrupted print pause. For this purpose, one or more subsequent pages and / or one or more preceding pages may have a pattern that can be accurately and reliably recognized by the post-processing unit. The insertion of one or more subsequent pages and / or one or more preceding pages makes it possible to significantly reduce the impact of the recognized raised portion 210 on the manufacturing process of the printed product.
[0039] The end and / or start of printing a page of a valid print image may occur earlier or later by the amount of time required to print one or more subsequent pages or one or more preceding pages.
[0040] In other words, the printing device 100 may be configured to treat the obstruction 210 of the recording medium 120 not as an error that causes printing to stop, but as a change of state that results in a printing pause, particularly a temporary and / or time-limited printing pause. If necessary, one or more subsequent pages may be inserted, particularly before the start of the printing pause, so that the post-processing machine can more easily handle the printing interruption and then synchronize again with the printed pages of the valid print image.
[0041] After the printing operation in one of the printing units 141, 142 is paused, the defective area 210 in the recording medium 120 reaches the first printing bar 102 of the printing unit 141, 142. In particular, in the case of a printing apparatus 100 equipped with multiple printing units 141, 142 for double-sided printing, one or more subsequent printing units 142 can continue printing without interruption while the printing of the first printing unit 141 is paused. In this case, the recording medium 120 proceeds at the maximum transport speed 304.
[0042] One or more print bars 102, i.e., one or more print bars 102 of the first printing unit 141, are lifted away from the surface of the recording medium 120 during printing pauses, after which defective areas 210 of the recording medium 120 reach each print bar 102. The defective areas 210 are then transported through the individual print bars 102. The individual print bars 102 are then moved again toward the surface of the recording medium 120, and the printing operation can be automatically resumed. If necessary, the control device 101 may insert one or more preceding pages so that post-processing can be synchronized with subsequent pages of the valid printed image.
[0043] Next, in the printing apparatus 100, which is equipped with multiple printing units 141 and 142, the defective portion 210 of the recording medium 120 is transported to the second printing unit 142. Here, the process proceeds in the same manner as with the preceding first printing unit 141. That is, after the printing operation is paused, the obstacle 210 reaches the printing bar 102 of the second printing unit 142. Each printing bar 102 is lifted away from the surface of the recording medium 120, the recording medium 120 is transported through each printing bar 102, and then each printing bar 102 is brought back to the printing position. The printing operation continues along the page to match the valid printed image already printed by the first printing unit 141. While the printing of the second printing unit 142 is paused, the first printing unit 141 continues to print continuously.
[0044] In some cases, particularly in the case of a double-sided printing device 100, a simplified implementation may be applied that allows the defective area 210 to pass through the entire double-sided printing device 100 until after it has passed through the second printing unit 142.
[0045] If an obstacle 210 in the recording medium 120 is detected, the printing process may be paused. Then, the print bars 102 of one or more printing units 141,142 are moved away from the recording medium 120, and the obstacle 210 is still allowed to pass through the entire printing apparatus 100, in particular all of the printing units 141,142 of the printing apparatus 100, at the maximum transport speed 304.
[0046] In some cases, after the recognized obstacle 210 has passed the entire printing device 100, the recording medium 120 may automatically stop along the stopping inclined surface. In this case, a relatively short stop state of the recording medium 120 may occur. Then, the printing operation can be automatically resumed. In this way, the described means can be carried out particularly efficiently. Furthermore, in this manner, the user of the printing device 100 can become aware of the presence of the obstacle 210 to the recording medium 120.
[0047] The printing pause of printing units 141, 142 caused by the recognized obstacle or protrusion 210 may be short, thereby eliminating the need to clean one or more print heads 103 following the printing pause. The control device 101 may be configured to calculate the length of the printing pause for printing units 141, 142 or print heads 103. This may be done, for example, based on the formula described above. Then, based on the calculated length, it can be determined whether or not the print heads 103 are cleaned in the regeneration unit 150 before the resumption of printing operation following the printing pause. By avoiding the cleaning of the print heads 103, the impact of the recognized protrusion 210 on the productivity and / or efficiency of the printing apparatus 100 can be significantly reduced.
[0048] Figure 4 shows a flowchart of an exemplary method 400, optionally performed by a computer, for controlling a printing apparatus 100, in particular an inkjet printing apparatus 100, having at least one printing unit 141,142 with at least one print bar 102. The print bar 102 may have, for example, one print head 103 or more print heads 103. Method 400 can be performed by a control device 101 of the printing apparatus 100.
[0049] The printing apparatus 100 is configured to create relative movement between the print bar 102 and / or print head 103 and the recording medium 120 to be printed by the print head 103, thereby sequentially printing rows of the valid print image onto the recording medium 120 during printing. The relative movement may occur along a predetermined transport direction 1, in which case the transport direction 1 may extend perpendicular to the arrangement of the individual rows of the valid print image. Within the framework of relative movement, the recording medium 120 may be guided through the stationary print bar 102 and / or the stationary print head 103. The recording medium 120 may be a web-like, sheet-like, or single-fed recording medium 120.
[0050] Method 400 includes a step 401 for detecting any raised portions 210 of the recording carrier 120 to be printed, particularly any raised portions 210 that are larger or higher than the printing gap between the print bar 102 and / or print head 103 and the recording carrier 120. The raised portions 210 may be detected based on sensor data from a sensor unit 110, in which case the sensor unit 110 is located upstream of the print units 141,142 with respect to the transport direction 1, particularly upstream of the print bar 102 and / or print head 103 of the print units 141,142.
[0051] Furthermore, method 400 includes a step 402, in particular an automatic step 402, which, in response to the detection 401 of the raised portion 210, causes a print pause in the print operation of the print bar 102 and / or print head 103 while the relative movement between the print bar 102 and / or print head 103 is continuing. In this case, the transport speed 304 of the relative speed may be maintained. On the other hand, during the print pause, the print operation for printing the valid print image is interrupted. In this case, the interruption occurs at a specific point in the valid print image, in particular after the completion of printing a specific page of the valid print image.
[0052] Method 400 further includes step 403, in particular step 403, which is performed automatically, to cause the print gap between the print bar 102 (and / or print head 103) and the recording medium 120 to widen during the print pause so that the detected protrusions 210 of the recording medium 120 can be guided through the print bar 102 (and / or print head 103) within the frame of the continued relative movement. The widening of the print gap may be caused by raising the print bar 102 (and / or print head 103).
[0053] Furthermore, method 400 includes a step 404, in particular an automatically occurring step 404, which causes the print gap between the print bar 102 (and / or print head 103) and the recording medium 120 to be reduced again after the detected raised portion 210 of the recording medium 120 has been guided through the print bar 102 (and / or print head 103). The reduction in the print gap may be caused by the descent of the print bar 102 (and / or print head 103).
[0054] Furthermore, method 400 includes a step 405 to resume the print operation of the print bar 102 (and / or print head 103) that prints the valid print image, in particular an automatic resume step 405, and a step to end the print pause after the print gap between the print bar 102 (and / or print head 103) and the recording medium 120 has been reduced. In this case, printing of the valid print image may be resumed from a specific point in the valid print image where the interruption in printing of the valid print image occurred, in particular immediately after a specific page.
[0055] Furthermore, this specification describes a control device 101 for controlling the printing apparatus 100, in particular the inkjet printing apparatus 100. The control device 101 has at least one printing unit 141, 142, each having at least one print head 103 and / or at least one print bar 102 equipped with one or more print heads 103. During printing, a predetermined printing gap may exist between the print bar 102 (and / or print head 103) and the recording carrier 120 to be printed, having a gap width of, for example, 2 mm or less.
[0056] The printing device 100 may be configured to cause relative movement between the print bar 102 (and / or print head 103) and the recording medium 120 to be printed by the print bar 102 (and / or print head 103), thereby sequentially printing rows of the valid print image onto the recording medium 120 during the printing operation. In this case, the valid print image may have a series of pages that are sequentially printed row by row onto the recording medium 120 during the printing operation.
[0057] The control device 101 may be configured to detect raised portions 210 of the recording carrier 120 to be printed. In this case, raised portions 210 that are larger or higher than the gap width of the printing gap between the print bar 102 (and / or print head 103) and the recording carrier 120 may be detected. The printing apparatus 100 may have a sensor unit 110, such as a camera, configured to detect sensor data relating to the print surface of the recording carrier 120. The control device 101 may be configured to detect raised portions 210 of the recording carrier 120 based on the sensor data from the sensor unit 110. The sensor unit 110 is configured to detect raised portions 210 of the recording carrier 120 at a predetermined spatial distance upstream of the printing units 141, 142, particularly upstream of the print bar 102 (and / or print head 103) of the printing units 141, 142, with respect to the transport direction 1 of relative movement. 1 31, 1 It's also acceptable to leave space 32 empty when arranging the elements.
[0058] The control device 101 may also be configured to pause the printing operation in response to the detection of a raised portion 210 of the recording carrier 120. In this case, the relative movement between the print bar 102 (and / or print head 103) and the recording carrier 120 may continue, especially during the printing pause. Furthermore, during the printing pause, the printing operation of the print bar 102 (and / or print head 103), especially when printing a valid print image, may be interrupted.
[0059] Furthermore, the control device 101 may be configured to widen the print gap between the print bar 102 (and / or print head 103) and the recording medium 120 during print pauses, particularly compared to the print gap applied during print operation. The widening of the print gap may be done so that the detected protrusions 210 of the recording medium 120 are guided through the print bar 102 (and / or print head 103) within the frame of continued relative movement, without coming into contact with the print bar 102 (and / or print head 103). For this purpose, the widening of the print gap may be caused according to the height of the protrusions 210 calculated based on sensor data from the sensor unit 110. In this way, damage to the print bar 102 (and / or print head 103) by the detected protrusions 210 of the recording medium 120 can be avoided particularly reliably and efficiently.
[0060] The control device 101 may also be configured to further reduce the printing gap between the printing units 141, 142 and the recording carrier 120 after the detected raised portion 210 of the recording carrier 120 has been guided through the printing units 141, 142 within the frame of the continued relative movement. In this case, the printing gap may be reduced to the gap width intended for printing operation.
[0061] Generally, the printing unit 141 or 142 may have at least one print head. Multiple print heads 103 for single-color printing may be arranged on a single print bar 102.
[0062] Furthermore, the control device 101 may be configured to terminate the printing pause and resume printing after the printing gap between the printing units 141, 142 and the recording medium 120 has been reduced.
[0063] In other words, the present invention describes a control device 101 configured to recognize a raised portion 210 on the recording medium 120 to be printed that could potentially damage the printing units 141 and 142 of the printing apparatus 100. The control device 101 is further configured to automatically cause a time-limited printing pause in the printing units 141 and 142, during which the printing gap between the printing units 141 and 142 and the recording medium 120 is temporarily widened, thereby guiding the detected raised portion 210 through the printing units 141 and 142. In this way, damage to the printing apparatus 100 can be efficiently and reliably avoided if there is a defect in the recording medium 120.
[0064] The control device 101 determines the start time 312, 314 for starting a print pause and / or the end time 313, 315 for ending a print pause based on the spatial distance between the sensor unit 110 and the print units 141, 142, particularly the print bar 102 and / or print head 103 of the print units 141, 142. 1 31, 1 The system may be configured to calculate according to 32. In this case, the start times 312, 314 may be calculated so that the detected raised portion 210 of the recording medium 120 reaches the print bars 102 and / or print heads 103 of the print units 141, 142, in particular, after the print pause has started. Alternatively or supplementarily, the end times 313, 315 may be calculated so that the print pause ends after the detected raised portion 210 of the recording medium 120 has been guided through the print bars 102 and / or print heads 103 of the print units 141, 142, in particular. In this way, damage to the print bars 102 and / or print heads 103 of the print units 141, 142 can be prevented particularly reliably and efficiently.
[0065] The relative movement between the printing units 141, 142 and the recording carrier 120 has a predetermined transport speed 304 during printing pauses. In this case, the transport speed 304 may not change significantly during printing pauses and may correspond to the transport speed 304 during printing operation. The control device 101 may be configured to calculate the start and / or end times of the printing pause with particular accuracy according to the transport speed 304 during the printing pause.
[0066] The control device 101 may be configured to cause the printing units 141 and 142 to print the subsequent print image onto the recording medium 120 before the start of the printing pause and after the interruption of printing of the valid print image. Alternatively or supplementally, the control device 101 may be configured to print the preceding print image onto the recording medium 120 after the end of the printing pause and before the resumption of printing of the valid print image. In this case, the subsequent print image and / or the preceding print image may each have a predetermined pattern, which allows a post-processing device added to the printing device 100, such as a cutting unit, to identify the valid print image and / or confirm the position of the valid print image on the recording medium 120. In this way, reliable post-processing of the printed recording medium 120 can be achieved even if the recording medium 120 contains obstacles.
[0067] The control device 101 may be configured to initiate a print pause only after one page of the valid print image has been completely printed. In particular, after the print pause ends, and possibly immediately after printing any preceding print image, printing may resume from the page immediately following the page that has been completely printed in a sequence of pages of the valid print image. In other words, the print pause may be inserted in accordance with the pages within a sequence of pages of the valid print image. In this way, the impact of the recording carrier 120, including any obstructions, on the printing process can be significantly reduced.
[0068] The printing units 141, 142 may have, for example, a plurality of consecutive printing bars 102 for different colors and / or different ink types. The printing apparatus 100 may be configured such that, within the frame of relative movement, the detected raised portions 210 of the recording carrier 120 are guided in a predetermined order, particularly sequentially along the transport direction 1, through the consecutive printing bars 102 of the printing units 141, 142 and / or the print head 3.
[0069] The control device 101 may be configured to expand the printing gap between the continuous print bars 102 and / or continuous print heads 103 and the recording medium 120 in a predetermined order, with each gap delayed in time. In this case, the expansion of the printing gap may be performed specifically "at the exact moment" the raised portion 210 reaches each printing unit 141, 142. In other words, the expansion of the printing gap between the continuous printing units 141, 142 may be performed in a wave-like motion.
[0070] Alternatively or supplementally, the control device 101 may be configured to reduce the printing gap between consecutive printing units 141, 142 and the recording carrier 120, delaying each other in time, based on a predetermined order, as soon as the raised portion 210 of the recording carrier 120 is guided through each printing unit 141, 142. In this case, the reduction of the gap width of the printing gap can be started immediately each time the raised portion 210 passes through each printing unit 141, 142. That is, the reduction of the printing gap may correspond to the opposite direction to the expansion of the printing gap and may be performed in a wave-like motion.
[0071] Continuous expansion and / or contraction of the print gap significantly reduces the duration of printing pauses, thereby greatly reducing the impact of the recording carrier 120, including any obstructions. Furthermore, this also reduces the power required by the printing apparatus 100 for expanding and / or contracting the print gap.
[0072] The printing apparatus 100 may have a first printing unit 141 equipped with at least one first printing bar 102 for printing on the surface of the recording medium 120, for example. Furthermore, the printing apparatus 100 may have a second printing unit 142 equipped with at least one second printing bar 102 for printing on the back surface of the recording medium 120, for example. The printing apparatus 100 may be configured such that, within the frame of relative movement, the detected raised portion 210 of the recording medium 120 is first guided through the first printing unit 141 and then through the second printing unit 142.
[0073] The control device 101 may be configured to pause printing in the first printing unit 141 while the detected raised portion 210 of the recording carrier 120 is guided through the first printing unit 141, and to continue printing in the second printing unit 142. Alternatively or supplementarily, the control device 101 may be configured to pause printing in the second printing unit 142 while the detected raised portion 210 of the recording carrier 120 is guided through the second printing unit 142, and to continue printing in the first printing unit 141. In other words, a time-limited printing pause may be selectively induced for each individual printing unit 141, 142. In this way, the influence of the recording carrier 120, including obstacles, on the printing process can be particularly reduced.
[0074] Alternatively, the control device 101 may be configured to create a time-connected printing pause between the first printing unit 141 and the second printing unit 142 of sufficient length to guide the detected raised portion 210 of the recording carrier 120 through the first printing unit 141 and the second printing unit 142. In other words, a connected printing pause may be created for multiple printing units 141, 142, and this can be done particularly efficiently and reliably in the printing apparatus 100.
[0075] The control device 101 may be configured to calculate the duration of the print pause before resuming print operation following the print pause. In particular, the continuous duration while the print units 141 and 142 are not being used for printing images may be calculated. In this case, depending on the calculated duration of the print pause, a regeneration procedure for the print units 141 and 142 may be initiated or stopped before resuming print operation. In this way, high print quality of the printing apparatus 100 can be efficiently guaranteed.
[0076] Furthermore, this specification describes a printing apparatus 100 having the control device 101 described herein.
[0077] The means described herein may reduce the duration of printing interruptions, i.e., printing pauses, based on the recognized protrusions 210, thereby reducing resource consumption and / or paper waste and / or increasing the productivity of the printing apparatus 100. Furthermore, based on the shortened printing interruptions, cleaning of one or more print heads 103 of the printing apparatus 100 following the printing pause may be avoided, thereby reducing ink consumption and significantly increasing the productivity of the printing apparatus 100. In addition, based on the automatic insertion of printing pauses and the automatic restart of printing, manual intervention by the user of the printing apparatus 100 may be avoided, thereby significantly increasing the efficiency of the printing apparatus 100. [Explanation of symbols]
[0078] 1. Conveying direction (of the recording medium) 2. Direction of movement (of the print bar) 21, 22 nozzles 31, 32 (of the printed image) 100 Printing equipment 101 Control Unit / Control Device 102 Print Bar 103 Printhead 110 Sensor Unit 131,132 spatial distance 120 Recording Carrier 141,142 Printing Units 150 Regeneration Units 160 Reversible Unit 210 Raised portion (recording carrier) 301 Control signal for the first printing unit 302 Control signal for the second printing unit 303 Print pause signal 304 Conveying speed As of 311-315 331,332 time intervals 333 Print pause length 400 Method for operating a printing device when a raised portion of the recording medium is detected. Steps 401-405
Claims
1. A control device for controlling a printing apparatus (100) having at least one printing element (102, 103, 141, 142), wherein the printing element has at least one printing unit (141, 142), at least one printing bar (102), and / or at least one printing head (103), and the printing apparatus (100) causes relative movement between the printing element (102, 103, 141, 142) and a recording medium (120) to be printed by the printing element (102, 103, 141, 142), thereby sequentially printing a series of valid print images onto the recording medium (120) during printing operation. The control device (101) is The recording carrier (120) to be printed on is detected, In response to the detection of the raised portion (210), the printing operation is paused while the relative movement between the printing element (102, 103, 141, 142) and the recording carrier (120) continues. During the aforementioned printing pause, the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) is widened, thereby allowing the detected raised portion (210) of the recording carrier (120) to be guided through the printing unit (141, 142) during the continued relative movement. After the detected raised portion (210) of the recording carrier (120) is guided through the printing unit (141, 142), the printing gap between the printing element (102, 103, 141, 142) and the recording carrier (120) is reduced again. The printing operation is restarted after the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) has been reduced. It is configured in such a way, The printing apparatus (100) comprises a first printing unit (141) having at least one print bar (102) and / or at least one print head (103), and a second printing unit (142) having at least one print bar (102) and / or at least one print head (103), The printing apparatus (100) is configured such that, during relative movement, the detected raised portion (210) of the recording carrier (120) is first guided through the first printing unit (141), and then guided through the second printing unit (142). The control device (101) is configured to cause a time-connected printing pause between the first printing unit (141) and the second printing unit (142) of sufficient length to guide the detected raised portion (210) of the recording carrier (120) through the first printing unit (141) and the second printing unit (142).
2. A control device for controlling a printing apparatus (100) having at least one printing element (102, 103, 141, 142), wherein the printing element has at least one printing unit (141, 142), at least one printing bar (102) and / or at least one printing head (103), and the printing apparatus (100) causes relative movement between the printing element (102, 103, 141, 142) and a recording carrier (120) to be printed by the printing element (102, 103, 141, 142), thereby sequentially printing a series of valid print images onto the recording carrier (120) during printing operation. The control device (101) is The recording carrier (120) to be printed on is detected, In response to the detection of the raised portion (210), the printing operation is paused while the relative movement between the printing element (102, 103, 141, 142) and the recording carrier (120) continues. During the aforementioned printing pause, the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) is widened, thereby allowing the detected raised portion (210) of the recording carrier (120) to be guided through the printing unit (141, 142) during the continued relative movement. After the detected raised portion (210) of the recording carrier (120) is guided through the printing unit (141, 142), the printing gap between the printing element (102, 103, 141, 142) and the recording carrier (120) is reduced again. The printing operation is restarted after the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) has been reduced. It is configured in such a way, The control device (101) is Before resuming printing operations following the aforementioned printing pause, the duration of the printing pause is calculated, and Depending on the calculated duration of the print pause, the regeneration process of the print bar (102) and / or the print head (103) is initiated or stopped before the print operation is resumed. A control device configured in such a way.
3. The printing apparatus (100) has a sensor unit (110) configured to detect sensor data relating to the printed surface of the recording carrier (120) in order to detect the raised portion (210) of the recording carrier (120), The sensor unit (110) is positioned with respect to the transport direction (1) of the relative movement, upstream of the printing units (141, 142), particularly upstream of the printing bar (102) and / or the printing head (103) of the printing units (141, 142), at a predetermined spatial distance (131, 132), and The control device (101) is configured to calculate the start time (312, 314) for starting the print pause and / or the end time (313, 315) for ending the print pause according to a predetermined spatial distance (131, 132), thereby, in particular, After the printing pause begins, the detected raised portion (210) of the recording carrier (120) reaches the printing unit (141, 142), in particular the print bar (102) and / or the print head (103) of the printing unit (141, 142), and / or The printing pause is terminated after the detected raised portion (210) of the recording carrier (120) has been guided through the printing unit (141, 142), particularly through the printing bar (102) and / or the print head (103) of the printing unit (141, 142). The control device according to claim 1 or 2.
4. The relative movement between the printing elements (102, 103, 141, 142) and the recording carrier (120) has a predetermined transport speed (304) during the printing pause. The transport speed (304) during the print pause corresponds in particular to the transport speed (304) during print operation, and The control device (101) is configured to calculate the start time (312, 314) for starting the print pause and / or the end time (313, 315) for ending the print pause, according to a predetermined transport speed (304). The control device according to any one of claims 1 to 3.
5. The control device (101) controls the printing elements (102, 103) Before the start of the aforementioned print pause and after the interruption of printing of the effective print image, the subsequent print image is to be printed on the recording carrier (120), and / or After the aforementioned printing pause has ended and before printing of the effective print image has resumed, the preceding print image is printed onto the recording carrier (120). It is configured in such a way, The control device according to any one of claims 1 to 4, wherein the subsequent printed image and / or the preceding printed image have a pattern that enables a post-processing device following the printing apparatus (100) to identify the effective printed image and / or to confirm the position of the effective printed image on the recording carrier (120).
6. The effective printed image has continuous pages, The control device (101) is configured to initiate the print pause only after one page of the valid print image has been completely printed, and in particular, after the print pause ends, printing can be resumed from the page immediately following the page that has been completely printed in the sequence of pages of the valid print image. The control device according to any one of claims 1 to 5.
7. The printing unit (141, 142) has a plurality of consecutive print bars (102) and / or a plurality of consecutive print heads (103), The printing apparatus (100) is configured such that, during the relative movement, the detected raised portion (210) of the recording carrier (120) is guided sequentially in a predetermined order through the continuous printing bars (102) and / or a plurality of continuous printing heads (103) of the printing units (141, 142), The control device (101) is configured to, during the printing pause, expand the printing gap between the consecutive print bars (102) and / or the consecutive print heads (103) and the recording medium (120) by delaying each other in time according to a predetermined order, and / or The control device (101) is configured such that, as soon as the raised portion (210) of the recording carrier (120) is guided through each of the print bars (102) and / or each of the print heads (103), it reduces the print gap between the consecutive print bars (102) and / or the consecutive print heads (103) and the recording carrier (120) by delaying each other in time according to a predetermined order. The control device according to any one of claims 1 to 6.
8. A method for controlling a printing apparatus (100) having at least one printing element (102, 103, 141, 142), wherein the printing element has at least one printing unit (141, 142), at least one printing bar (102) and / or at least one printing head (103), and the printing apparatus (100) is configured to cause relative movement between the printing unit (141, 142) and a recording medium (120) to be printed by the printing unit (141, 142), thereby printing a sequence of valid print images onto the recording medium (120) sequentially during printing, wherein the method (400) includes, The steps include detecting the raised portion (210) of the recording carrier (120) to be printed on (401), Step (402) of causing a pause in the printing operation of the printing elements (102, 103, 141, 142) while the relative movement between the printing elements (102, 103, 141, 142) and the recording carrier (120) is continuing in response to the detection of the raised portion (210), Step (403) of widening the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) during the printing pause, thereby allowing the detected raised portion (210) of the recording carrier (120) to be guided through the printing elements (102, 103, 141, 142) during the continued relative movement, After the detected raised portion (210) of the recording carrier (120) is guided through the printing elements (102, 103, 141, 142), the step (404) of reducing the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) again, Step (405) to restart the printing operation of the printing elements (102, 103, 141, 142) after the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) has been reduced. It includes, The printing apparatus (100) comprises a first printing unit (141) having at least one print bar (102) and / or at least one print head (103), and a second printing unit (142) having at least one print bar (102) and / or at least one print head (103), During the relative movement, the detected raised portion (210) of the recording carrier (120) is first guided through the first printing unit (141), and then guided through the second printing unit (142). A method for causing a time-connected printing pause between the first printing unit (141) and the second printing unit (142) of a length sufficient to guide the detected raised portion (210) of the recording carrier (120) through the first printing unit (141) and the second printing unit (142).
9. A method for controlling a printing apparatus (100) having at least one printing element (102, 103, 141, 142), wherein the printing element has at least one printing unit (141, 142), at least one printing bar (102) and / or at least one printing head (103), and the printing apparatus (100) is configured to cause relative movement between the printing unit (141, 142) and a recording medium (120) to be printed by the printing unit (141, 142), thereby printing a sequence of valid print images onto the recording medium (120) during printing, wherein the method (400) includes: The steps include detecting the raised portion (210) of the recording carrier (120) to be printed on (401), Step (402) of causing a pause in the printing operation of the printing elements (102, 103, 141, 142) while the relative movement between the printing elements (102, 103, 141, 142) and the recording carrier (120) is continuing in response to the detection of the raised portion (210), Step (403) of widening the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) during the printing pause, thereby allowing the detected raised portion (210) of the recording carrier (120) to be guided through the printing elements (102, 103, 141, 142) during the continued relative movement, After the detected raised portion (210) of the recording carrier (120) is guided through the printing elements (102, 103, 141, 142), the step (404) of reducing the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) again, Step (405) to restart the printing operation of the printing elements (102, 103, 141, 142) after the printing gap between the printing elements (102, 103, 141, 142) and the recording carrier (120) has been reduced. It includes, Before resuming printing operations following the aforementioned printing pause, the duration of the printing pause is calculated, and A method for initiating or stopping a regeneration procedure of the print bar (102) and / or the print head (103) before resuming the print operation, in accordance with the calculated duration of the print pause.