Patent Application
20240278578
The present invention relates to a printing apparatus and a maintenance method therefor.
There has been known an inkjet printing apparatus that performs printing by ejecting ink onto a base material (print medium) such as print paper. In the inkjet printing apparatus, when an interval between ejections is long, drying of ink due to evaporation of solvent near a nozzle, mixing of air bubbles into the nozzle, adhesion of dust to the nozzle, or the like may occur in a period during which printing is performed. When such a phenomenon occurs, normal ejection or the like cannot be performed, and printing failure may occur. Therefore, maintenance for avoiding such a problem is performed at any time.
Maintenance is broadly classified into cleaning, such as wiping (wiping the dirt off) the nozzle surface of an inkjet head (printhead) with a dedicated mechanism, and flushing, in which an ink ejecting operation unrelated to the print content is forcibly performed. Flushing can be performed while the print paper is being conveyed, but cleaning needs to be performed while conveyance of the print paper is stopped. There are various types of flushing methods, and the following are known: star flushing (discrete flushing) in which ink is ejected to form a thin layer of ink on the entire page to be printed; line flushing in which ink is simultaneously ejected from a plurality of nozzles on a predetermined row of a certain page; and other types.
Regarding the maintenance as described above, Japanese Laid-Open Patent Publication No. 2011-152689 discloses a printing apparatus that determines whether an ejection state is a normal state, a clogged state, or an unstable ejection state based on an actual measurement value indicating the ejection state of ink, and performs different maintenance depending on the determination result. In the printing apparatus, for example, when it is determined that the ink ejection state is the clogged state, maintenance including an ink suction operation is performed, when it is determined that the ink ejection state is the unstable ejection state, maintenance not including the ink suction operation is performed, and when it is determined that the ink ejection state is the normal state, maintenance is not performed.
Further, WO 2015/163087 discloses a maintenance system of an inkjet recording apparatus, the maintenance system including a maintenance level determination criterion correction portion that corrects a maintenance level determination criterion for determining the content of maintenance to be performed. In the maintenance system, for example, the maintenance level determination criterion is automatically corrected based on the processing time of the job to be processed next to the current job. As a more specific example, when the processing time of the job to be processed next is longer than the processing time defined by the standard, the maintenance level determination criterion is corrected such that maintenance with high recovery capability is performed even at a low ejection abnormality level.
In recent years, printing apparatuses having an auto-splice function have been developed. The auto-splice function is a function of automatically splicing the tail end part of the roll paper to be used currently and the start end part of the roll paper to be used next, using an adhesive tape or the like, when the remaining amount of the roll paper to be used currently becomes small. The printing apparatus having such an auto-splice function eliminates the need for manual replacement work of the roll paper, thereby reducing the printing time.
In a conventional printing apparatus, maintenance is not performed when printing is continuously performed on a plurality of rolls of paper using the auto-splice function. However, before and after the replacement of the roll paper, the head (inkjet head) to be used may vary, and the level of print quality required by a user may vary. In such a case, it is considered preferable to perform maintenance. Note that neither Japanese Laid-Open Patent Publication No. 2011-152689 nor WO 2015/163087 describes maintenance in a case where roll paper is replaced using the auto-splice function.
Therefore, an object of the present invention is to achieve a printing apparatus that has an auto-splice function and is capable of performing, when roll paper is replaced, suitable maintenance taking into account a print process scheduled to be executed after replacement of the roll paper.
A first aspect of the present invention is directed to a printing apparatus including:
According to a second aspect of the present invention, in the first aspect of the present invention,
According to a third aspect of the present invention, in the second aspect of the present invention,
According to a fourth aspect of the present invention, in the second aspect of the present invention,
According to a fifth aspect of the present invention, in the second aspect of the present invention,
According to a sixth aspect of the present invention, in the second aspect of the present invention,
According to a seventh aspect of the present invention, in the second aspect of the present invention,
According to an eighth aspect of the present invention, in the first aspect of the present invention,
According to a ninth aspect of the present invention, in the eighth aspect of the present invention,
According to a tenth aspect of the present invention, in the eighth aspect of the present invention,
According to an eleventh aspect of the present invention, in the eighth aspect of the present invention,
According to a twelfth aspect of the present invention, in the eighth aspect of the present invention,
According to a thirteenth aspect of the present invention, in the first aspect of the present invention,
According to a fourteenth aspect of the present invention, in the first aspect of the present invention,
According to a fifteenth aspect of the present invention, in the first aspect of the present invention,
A seventeenth aspect of the present invention is directed to a maintenance method of a printing apparatus that includes
According to the first aspect of the present invention, a printing apparatus having an auto-splice function is provided with a maintenance mechanism that performs maintenance of a printhead, a maintenance content control unit that determines maintenance content for the printhead, and a maintenance mechanism control unit that controls the operation of the maintenance mechanism such that the maintenance based on the maintenance content determined by the maintenance content control unit is performed. Then, when the roll paper to be used is replaced, the maintenance content control unit determines the maintenance content for the printhead in accordance with a criterion suitable for printing on continuous paper unwound from the roll paper after replacement based on the inspection result for the inspection pattern. As a result, when the roll paper is replaced, maintenance is performed on the printhead depending on the print process to be executed after the replacement. As above, the printing apparatus is achieved that has the auto-splice function and is capable of performing, when the roll paper is replaced, suitable maintenance taking into account the print process scheduled to be executed after replacement of the roll paper.
According to the second aspect of the present invention, in a case where some of the printheads to be used before replacement of the roll paper will not be used after replacement of the roll paper, the need for maintenance of each printhead to be used after replacement of the roll paper is suitably determined.
According to the third aspect of the present invention, the printing time is reduced by preventing maintenance from being performed more than necessary.
According to the fourth aspect of the present invention, when maintenance is performed on the printhead to be used after replacement of the roll paper, maintenance is performed on the printhead not to be used after replacement of the roll paper together. Accordingly, maintenance is efficiently performed. In addition, when maintenance is not performed on the printhead to be used after replacement of the roll paper, maintenance is not performed on the printhead not to be used after replacement of the roll paper. Thus, the printing time is reduced by preventing maintenance from being performed more than necessary.
According to the fifth aspect of the present invention, when roll paper having a wide width is replaced with roll paper having a narrow width, suitable maintenance corresponding to the print process on narrow continuous paper is performed.
According to the sixth aspect of the present invention, when color printing is switched to monochrome printing at the replacement of the roll paper, suitable maintenance is performed, taking into account the execution of monochrome printing.
According to the seventh aspect of the present invention, when double-sided printing is switched to single-sided printing at the replacement of the roll paper, suitable maintenance is performed taking into account the execution of single-sided printing.
According to the eighth aspect of the present invention, since maintenance is reliably performed on the printhead that changes from the non-use state to the used state at the replacement of the roll paper, the occurrence of ejection failure of the printhead that has been in the non-use state is effectively inhibited.
According to the ninth aspect of the present invention, the need for maintenance is suitably determined for each printhead maintained in the use state throughout a period before and after replacement of the roll paper.
According to the tenth aspect of the present invention, when roll paper having a narrow width is replaced with roll paper having a wide width, suitable maintenance corresponding to the print process on continuous paper having a wide width is performed.
According to the eleventh aspect of the present invention, when monochrome printing is switched to color printing at the replacement of the roll paper, suitable maintenance is performed, taking into account the execution of color printing.
According to the twelfth aspect of the present invention, when single-sided printing is switched to double-sided printing at the replacement of the roll paper, suitable maintenance is performed, taking into account the execution of double-sided printing.
According to the thirteenth aspect of the present invention, in a case where a plurality of jobs are print targets in a period from when the roll paper is replaced to when the roll paper is replaced next, the occurrence of ejection failure of a printhead to be used for printing of the plurality of jobs is effectively inhibited.
According to the fourteenth aspect of the present invention, it is possible to effectively inhibit the occurrence of printing failure after replacement of the roll paper.
According to the fifteenth aspect of the present invention, by appropriately using cleaning and flushing, it is possible to inhibit a decrease in printing efficiency while maintaining printing quality.
According to the sixteenth aspect of the present invention, it is possible to automatically perform not only the splicing of the tail end part of the preceding roll paper and the start end part of the subsequent roll paper but also the printing of the inspection pattern.
According to the seventeenth aspect of the present invention, the same effect as that of the first aspect of the present invention can be obtained.
Embodiments of the present invention will be described below with reference to the accompanying drawings.
Although the image inspection device 300 is a component of the inkjet printing apparatus 10 (i.e., the image inspection device 300 is included in the inkjet printing apparatus 10) in the configuration shown in
The printer body 200 includes a paper feeding unit 21 for supplying print paper (roll paper) PA, a printing mechanism 20 for performing printing on the print paper PA, and a paper winding unit 28 for winding the print paper PA after printing. The printing mechanism 20 includes a first drive roller 22 for conveying the print paper PA to its inside, a plurality of support rollers 23 for conveying the print paper PA inside the printing mechanism 20, a printing unit 24 for performing printing by ejecting ink onto the print paper PA, a cleaning mechanism 25 for performing cleaning (e.g., suction of ink from the nozzle described later or wiping of the nozzle surface) of the printing unit 24, a drying unit 26 for drying the print paper PA after printing, an imaging unit 310 for capturing a print image (print paper PA after printing), and a second drive roller 27 for outputting the print paper PA from the inside of the printing mechanism 20. The imaging unit 310 is a component of the image inspection device 300 and is configured using an image sensor such as a charged coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS).
The print control device 100 controls the operation of the printer body 200 having the configuration as above. When a printout instruction command is given to the print control device 100, the print control device 100 controls the operation of the printer body 200 such that the print paper PA is conveyed from the paper feeding unit 21 to the paper winding unit 28. Then, first, printing is performed on the print paper PA by the printing unit 24, next, the print paper PA is dried by the drying unit 26, and finally, a print image is captured by the imaging unit 310. When necessary, the cleaning mechanism 25 cleans the printing unit 24.
The image inspection device 300 includes the imaging unit 310 and an image inspection computer 320. Captured image data Di obtained by capturing the print image performed by the imaging unit 310 is transmitted to the image inspection computer 320. The image inspection computer 320 performs an inspection for detecting a defect (missing) by performing image analysis on the captured image data Di. Note that the present invention is not limited to such a method, and inspection for detecting a defect (missing) or the like may be performed by comparing and collating the captured image data Di with print data Dp transmitted from the print data generation apparatus 40 or by comparing and collating the captured image data Di with inspection image data Dc. An inspection result Dr obtained by the image inspection computer 320 is transmitted to the print control device 100.
Meanwhile, the inkjet printing apparatus 10 has the auto-splice function described above. Therefore, as shown in
Although the configuration of the inkjet printing apparatus 10 for performing color printing has been exemplified here, the present invention can also be applied to a case where an inkjet printing apparatus for performing monochrome printing is employed. Although the configuration of the inkjet printing apparatus 10 using the aqueous ink has been exemplified here, the present invention can also be applied to a case where an inkjet printing apparatus using ultraviolet (UV) ink (ultraviolet curing ink) such as an inkjet printing apparatus for label printing is employed. As above, the type of the printing apparatus is not particularly limited as long as the printing apparatus has the auto-splice function and includes the printing unit that ejects ink and requires cleaning.
The auxiliary storage device 121 stores a print control program (a program for controlling the execution of the print process by the printer body 200) P. The CPU 111 reads the print control program P stored in the auxiliary storage device 121 into the memory 112 and executes the program to achieve various functions of the print control device 100. The memory 112 includes a random-access memory (RAM) and a read-only memory (ROM). The memory 112 functions as a work area for the CPU 111 to execute the print control program P stored in the auxiliary storage device 121. Note that the print control program P is provided by being stored into the computer-readable recording medium (non-transitory recording medium). That is, for example, a user purchases the optical disc 6 as the recording medium of the print control program P, inserts the optical disc 6 into the optical disc drive 122, reads the print control program P from the optical disc 6, and installs the print control program P in the auxiliary storage device 121. Alternatively, the print control program P transmitted via the communication line 5 may be received by the network interface unit 118 and installed in the auxiliary storage device 121.
The maintenance content control unit 151 determines the content of maintenance of the printing unit 24 (more specifically, the inkjet head 241) based on the result of the inspection by the image inspection device 300 (the inspection result Dr obtained by the image inspection computer 320). Note that the maintenance content control unit 151 will be described later in further detail.
The conveyance control unit 152 controls the speed (conveyance speed) at which a conveyance mechanism 210 conveys the print paper PA. Note that, in the present embodiment, the conveyance mechanism 210 is implemented by the paper feeding unit 21, the first drive roller 22, the plurality of support rollers 23, the second drive roller 27, and the paper winding unit 28 (cf.
The print control unit 153 controls the ejection of ink from each of the nozzles included in the inkjet heads 241 constituting the printing unit 24. For example, the ink ejection timing and the ink ejection amount are controlled.
The maintenance mechanism control unit 154 controls an operation of a maintenance mechanism 250 in accordance with the content of maintenance determined by the maintenance content control unit 151. In this regard, the maintenance mechanism 250 includes a cleaning mechanism 25 that performs cleaning on the inkjet head 241 and a flushing mechanism 242 that performs flushing. The flushing mechanism 242 is included in the printing unit 24.
The drying control unit 155 controls a temperature (drying temperature) when the drying unit 26 dries the print paper PA. The inspection control unit 156 controls the timing for the imaging unit 310 to capture the print image.
As described above, the inkjet printing apparatus 10 according to the present embodiment has the auto-splice function. In a conventional inkjet printing apparatus, maintenance is not performed when roll paper is replaced using the auto-splice function. On the other hand, in the inkjet printing apparatus 10 according to the present embodiment, maintenance is performed on the inkjet head 241 when the roll paper is replaced using the auto-splice function. The control of that maintenance will be described in detail below.
Note that, in the following description, roll paper currently in use (roll paper to be used currently) is referred to as “preceding roll paper”, and roll paper to be used next is referred to as “subsequent roll paper”. Print paper in a state of continuous paper unwound from the preceding roll paper is referred to as “preceding print paper”, and print paper in a state of continuous paper unwound from the subsequent roll paper is referred to as “subsequent print paper”.
When the remaining amount of the preceding roll paper becomes small, a splice trigger signal ST is outputted from the splicer 213. The splice trigger signal ST is a signal that triggers the replacement of the roll paper. When the print control unit 153 receives the splice trigger signal ST, the print control unit 153 controls the operation of the printing unit 24 such that an inspection pattern for performing inspection for a defect (a missing such as a nozzle defect) is printed at the tail of the preceding print paper. The imaging unit 310 captures the print image for the inspection pattern, and the captured image data Di obtained by the imaging is transmitted to the image inspection computer 320. The image inspection computer 320 performs inspection for detecting a defect based on the captured image data Di, and the inspection result holding unit 157 holds the inspection result Dr.
The job information holding unit 158 holds various types of information (job information JI) such as print conditions for a job for which printing is reserved. From the splicer 213, paper information PI, such as paper types and paper widths of the preceding roll paper and the subsequent roll paper, is provided to the maintenance content control unit 151. When the maintenance content control unit 151 receives the splice trigger signal ST, the maintenance content control unit 151 determines the need for maintenance, the inkjet head 241 to be a maintenance target, and the type of maintenance, based on the job information JI, the paper information PI, and defect information LI that is an inspection result related to a defect among the inspection results Dr held in the inspection result holding unit 157. The maintenance mechanism control unit 154 controls the operations of the cleaning mechanism 25 and the flushing mechanism 242 in accordance with the content determined by the maintenance content control unit 151.
In the present embodiment, a criterion is provided for determining maintenance content that includes the need for maintenance and the specification of the inkjet head 241 to be a maintenance target. As an example, the number of defects is used as a criterion. In this case, for example, a criterion such as “maintenance is required when the number of defects is three or more” is defined. In addition, the criterion changes depending on the paper type, printing conditions, and the like. For example, under the premise that a first threshold is larger than a second threshold, when paper not requiring good quality is used, a criterion such as “maintenance is required when the number of defects is equal to or larger than the first threshold” is defined, whereas when paper requiring good quality is used, a criterion such as “maintenance is required when the number of defects is equal to or larger than the second threshold” is defined. According to this example, for the same inspection result, it is more likely that maintenance is determined to be necessary in the case where paper requiring good quality is used than in the case where paper not requiring good quality is used. Regarding the level of the criterion, in the present specification, it is assumed that the higher the criterion, the higher the possibility that maintenance is determined to be necessary.
Further, in the present embodiment, regarding the maintenance when the roll paper is replaced using the auto-splice function, the inkjet head 241 to be a maintenance target is specified in accordance with a criterion suitable for printing after the replacement of the roll paper.
As above, when the splicer 213 replaces, regarding the roll paper to be used, the preceding roll paper with the subsequent roll paper, the maintenance content control unit 151 determines the inkjet head 241 to be a maintenance target in accordance with the criterion suitable for printing on the subsequent print paper (continuous paper unwound from the subsequent roll paper) based on the inspection result Dr obtained by the inspection of the print image for the inspection pattern (the inspection pattern for performing inspection for defects of the printhead including a nozzle defect) performed by the image inspection device 300. Note that, in such a case, a function may be provided to notify and store the determination content when it is assumed that the criterion suitable for printing on the preceding print paper (continuous paper unwound from the preceding roll paper) is followed.
<1.5.2 Overall Process Flow when Replacement of Roll Paper is Performed>
With reference to a flowchart shown in
When the remaining amount of the preceding roll paper becomes small in a situation where printing on the preceding print paper (step S100) is being performed, the splice trigger signal ST is outputted from the splicer 213 (step S102). In this regard, specifically, a threshold for comparison with the remaining amount of the roll paper is provided, and when the remaining amount of the preceding roll paper becomes equal to or less than the threshold, the splicer 213 outputs the splice trigger signal ST.
In response to the output of the splice trigger signal ST, the inspection pattern described above is printed at the tail of the preceding print paper (step S104). Then, the image inspection device 300 inspects the print image for the inspection pattern (step S106). As for this, first, the imaging unit 310 captures the print image obtained by the printing in step S104. Next, captured image data Di obtained by imaging performed by the imaging unit 310 is transmitted to the image inspection computer 320. Then, the image inspection computer 320 performs image analysis of the captured image data Di. In this manner, a defect is detected based on the print image for the inspection pattern. Since the inspection based on the print image for the inspection pattern printed at the tail of the preceding print paper is performed in this manner, the inspection result indicating that there is no abnormality ensures that the print result of the job executed before the replacement of the roll paper is good.
After the inspection of the print image for the inspection pattern is completed, a process of determining the need for maintenance, the inkjet head 241 to be a maintenance target, and the type of maintenance (hereinafter referred to as a “maintenance content determination process”) is performed based on the inspection result (step S110). Then, it is determined whether or not maintenance is necessary (step S112). As a result, when it is determined that maintenance is necessary, the process proceeds to step S114, and when it is determined that maintenance is not necessary, the process proceeds to step S130. In step S114, the maintenance mechanism 250 performs maintenance of the inkjet head 241.
In parallel with the processes of steps S110 to S114, the roll paper is replaced (step S120). That is, the tail end part of the preceding print paper is spliced with the start end part of the subsequent print paper by the splicer 213, and the preceding roll paper is replaced with the subsequent roll paper regarding the roll paper to be used. In this manner, in step S120, the roll paper is replaced without manual operation.
In step S130, an inspection pattern is printed on the head part of the subsequent print paper. Then, the image inspection device 300 inspects the print image for the inspection pattern (step S132).
Thereafter, it is determined, based on the inspection result, whether it is necessary to stop printing (step S140). As a result, when it is determined that it is necessary to stop printing, the process proceeds to step S142, and when it is determined that it is not necessary to stop printing, the process proceeds to step S144. In step S142, printing is stopped. In this case, the conveyance of the subsequent print paper is stopped, and for example, the printing is resumed after the cleaning of the inkjet head 241 is performed. In step S144, printing on the subsequent print paper is performed.
Note that, in the present embodiment, an inspection pattern printing step is achieved by the above step S104, an inspection step is achieved by the above step S106, a maintenance content control step is achieved by the above step S110, a maintenance step is achieved by the above step S114, and a roll paper replacement step is achieved by the above step S120.
Next, the maintenance content determination process (step S110 in
<1.5.3.1 Replacement of Wide Paper with Narrow Paper>
With reference to a flowchart shown in
After the maintenance content determination process is started, first, the inspection result Dr (more specifically, the defect information LI which is the inspection result related to the defect among the inspection results Dr) for the inspection pattern printed at the tail of the preceding print paper (here, the wide paper 61) is acquired (step S200). Next, the paper information PI that is information such as a paper type and a paper width for each of the preceding print paper and the subsequent print paper (here, the narrow paper 62) is acquired (step S210). Furthermore, the job information JI, which is various types of information such as printing conditions for a job to be executed after the replacement of the roll paper, is acquired (step S220).
Next, based on the information of the paper width acquired in step S210, a head to be used after the replacement of the roll paper (hereinafter referred to as a “use head”) and a head not to be used after the replacement of the roll paper (hereinafter referred to as a “non-use head”) are specified (step S230). In this case, the heads H1 to H7 are specified as use heads, and the heads H8 to H10 are specified as non-use heads. Then, based on the inspection result Dr acquired in step S200, it is determined whether or not a defect is present on the use heads (step S240). As a result, when there is a defect on the use heads, the process proceeds to step S250. On the other hand, when there is no defect on the use heads, it is determined not to perform maintenance, and the maintenance content determination process ends.
In step S250, it is determined whether or not maintenance is necessary. Specifically, based on the inspection result Dr acquired in step S200, it is determined whether or not the maintenance of the use heads (the heads H1 to H7) is necessary in accordance with a criterion defined for printing on the narrow paper 62 (a criterion suitable for printing on the narrow paper 62). This determination is made, for example, based on a comparison result between the number of defects or the largest defect size and a predetermined threshold for the narrow paper 62 not for the wide paper 61. As a result, when it is determined that maintenance is necessary, the process proceeds to step S260. On the other hand, when it is determined that maintenance is not necessary, the maintenance content determination process ends. Note that the determination of the need for maintenance in step S250 is made not for each head but for the entire use heads (the entirety of the heads H1 to H7).
In step S260, a head to be a maintenance target is specified. In this case, a head having a defect among the use heads (heads H1 to H7) and a head having a defect among the non-use heads (heads H8 to H10) are set as a maintenance target. When there is a defect only in the head H1 among the use heads (heads H1 to H7), the heads H1, H8, and H10 are set as maintenance targets.
In step S270, based on the inspection result Dr acquired in step S200, it is determined whether or not cleaning is necessary for the heads that are maintenance targets in accordance with the criterion defined for printing on the narrow paper 62. Similarly to step S250, this determination is also made, for example, based on a comparison result between the number of defects or the largest defect size and a predetermined threshold for the narrow paper 62 not for the wide paper 61. As a result, when it is determined that cleaning is necessary, the process proceeds to step S272, and when it is determined that cleaning is not necessary, the process proceeds to step S274. When it is determined that cleaning is not necessary, flushing is performed. As above, the type of maintenance is determined in accordance with the criterion suitable for printing on the subsequent print paper (here, the narrow paper 62).
In step S272, the intensity at which cleaning is performed (cleaning intensity) is determined. In this regard, for example, the configuration may be such that the past inspection result is stored, and the cleaning intensity is determined based on the immediately preceding inspection result and the past inspection result. In addition, the cleaning intensity is determined in accordance with the criterion suitable for printing on the subsequent print paper (here, the narrow paper 62).
In step S274, the content of flushing is determined. In this regard, for example, the flushing amount and the number of flushing sheets (sheets on which a special pattern for improving defect is printed) are determined. The content of flushing is also determined in accordance with the criterion suitable for printing on the subsequent print paper (here, the narrow paper 62).
As above, in this example, only for the use heads, the printhead to be a maintenance target and the maintenance content (e.g., cleaning intensity and flushing content) are determined in accordance with the criterion suitable for printing on the subsequent print paper. Processing regarding the non-use heads will be described as follows. When there is a defect on the use heads and it is determined that maintenance is necessary in step S250, the non-use heads are included in the heads that are maintenance targets. On the other hand, when there is no defect on the use heads or when it is determined that maintenance is not necessary in step S250, maintenance is not performed on the non-use heads.
<1.5.3.2 Replacement of Narrow Paper with Wide Paper>
With reference to a flowchart shown in
After the maintenance content determination process is started, first, the inspection result Dr (more specifically, the defect information LI which is the inspection result related to the defect among the inspection result Dr) for the inspection pattern printed at the tail of the preceding print paper (here, the narrow paper 62) is acquired (step S300). Since the narrow paper 62 corresponds to the heads H1 to H7, the inspection result for the region corresponding to the heads H8 to H10 is not obtained. In step S310, the paper information PI is acquired similarly to step S210 in
Next, based on the paper width information acquired in step S310, a head to be used before the replacement of the roll paper (hereinafter referred to as a “used head”) and a head not to be used before the replacement of the roll paper (hereinafter referred to as an “unused head”) are specified (step S330). In this case, the heads H1 to H7 are specified as used heads, and the heads H8 to H10 are specified as unused heads.
Thereafter, it is determined whether or not the maintenance of the used head is necessary (step S340). Specifically, based on the inspection result Dr acquired in step S300, it is determined whether or not the maintenance of the used heads (the heads H1 to H7) is necessary in accordance with a criterion defined for printing on the wide paper 61 (a criterion suitable for printing on the wide paper 61). As a result, when it is determined that maintenance is necessary, the process proceeds to step S342, and when it is determined that maintenance is not necessary, the process proceeds to step S344.
In step S342, the head having a defect among the used heads (heads H1 to H7) and all the unused heads (heads H8 to H10) are set as a maintenance target. When there is a defect only in the head H1 among the used heads (heads H1 to H7), the head H1 and the heads H8 to H10 are set as a maintenance target.
In step S344, all the unused heads (heads H8 to H10) are set as a maintenance target.
In step S350, based on the inspection result Dr acquired in step S300, it is determined whether or not cleaning is necessary for the heads that are maintenance targets in accordance with a criterion defined for printing on the wide paper 61. As a result, when it is determined that cleaning is necessary, the process proceeds to step S352, and when it is determined that cleaning is not necessary, the process proceeds to step S354.
In step S352, the cleaning intensity is determined similarly to step S272 of
As above, in this example, only for the used heads, the printhead to be a maintenance target is determined in accordance with the criterion suitable for printing on the subsequent print paper. As for the unused heads, they are set as maintenance targets regardless of the need for the maintenance of the used heads.
According to the present embodiment, the control unit 150 of the inkjet printing apparatus 10 having an auto-splice function is provided with the maintenance content control unit 151 for determining the need for maintenance of the inkjet head 241, the inkjet head 241 to be a maintenance target; and the type of maintenance, and the maintenance mechanism control unit 154 for controlling the operations of the cleaning mechanism 25 and the flushing mechanism 242 in accordance with the content determined by the maintenance content control unit 151. When the splicer 213 replaces the roll paper to be used, the maintenance content control unit 151 determines the inkjet head 241 to be a maintenance target in accordance with a criterion suitable for printing on the subsequent print paper based on the inspection result for the inspection pattern. Accordingly, when the roll paper is replaced, maintenance is performed on the inkjet head 241 depending on the print process performed after the replacement. As above, according to the present embodiment, the inkjet printing apparatus 10 is achieved that has the auto-splice function and is capable of performing, when the roll paper is replaced, suitable maintenance taking into account the print process scheduled to be executed after the replacement.
Further, according to the present embodiment, at the time of replacing the wide paper 61 with the narrow paper 62, in a case where there is no defect on the inkjet head 241 to be used after the replacement of the roll paper, or in a case where there is a defect on the inkjet head 241 to be used after the replacement of the roll paper but maintenance of that inkjet head 241 is not necessary, maintenance is not performed for any of the inkjet heads 241. Thus, the printing time is reduced by preventing maintenance from being performed more than necessary.
Moreover, according to the present embodiment, when the narrow paper 62 is replaced with the wide paper 61, all the inkjet heads 241, which have not been used before the replacement of the roll paper, are set as a maintenance target. Since the maintenance is reliably performed on the inkjet head 241 that changes from the non-use state to the used state at the replacement of the roll paper in this manner, the occurrence of the ejection failure of the inkjet head 241 that has been in the non-use state is effectively inhibited.
Moreover, according to the present embodiment, cleaning and flushing are prepared as types of maintenance of the inkjet head 241. By appropriately using cleaning and flushing, it is possible to inhibit a decrease in printing efficiency while maintaining printing quality.
In the description of the above embodiment, the focus has been on the case where the paper width changes at the replacement of the roll paper. However, the present invention can also be applied to other cases. Therefore, a case where switching between double-sided printing and single-sided printing is performed at the replacement of the roll paper will be described as a first modification, and a case where switching between color printing and monochrome printing is performed at the replacement of the roll paper will be described as a second modification. Note that, in the description of these modifications, the inkjet head is abbreviated as a “head”.
When single-sided printing is performed, the ejection of ink from the printing unit to the print paper is stopped in either the first printing mechanism 20a or the second printing mechanism 20b. That is, heads are used in both the first printing mechanism 20a and the second printing mechanism 20b when double-sided printing is performed, whereas heads are used only in either the first printing mechanism 20a or the second printing mechanism 20b when single-sided printing is performed. In this manner, when single-sided printing is performed, some of the plurality of heads used when double-sided printing is performed are used. Therefore, “switching from double-sided printing to single-sided printing” at the replacement of the roll paper corresponds to “replacement of the wide paper 61 with the narrow paper 62” in the first embodiment, and “switching from single-sided printing to double-sided printing” at the replacement of the roll paper corresponds to “replacement of the narrow paper 62 with the wide paper 61” in the first embodiment.
When double-sided printing is switched to single-sided printing at the replacement of the roll paper, the maintenance content determination process is executed in the same procedure as in the “replacement of the wide paper 61 with the narrow paper 62” in the first embodiment (cf.
When single-sided printing is switched to double-sided printing at the replacement of the roll paper, the maintenance content determination process is executed in the same procedure as in the “replacement of the narrow paper 62 with the wide paper 61” in the first embodiment (cf.
As above, according to the present modification as well, in the inkjet printing apparatus 10 having the auto-splice function, when the roll paper is replaced, suitable maintenance is performed taking into account the print process scheduled to be executed after the replacement.
When the printing unit 24 having the configuration as shown in
For color printing, C color ink, M color ink, Y color ink, and K color ink are used. That is, when color printing is performed, a head for ejecting the C color ink (hereinafter referred to as a “C color head”), a head for ejecting the M color ink (hereinafter referred to as an “M-color head”), a head for ejecting the Y color ink (hereinafter referred to as a “Y color head”), and a head for ejecting the K color ink (hereinafter referred to as a “K color head”) are used. In the present modification, only the K color head is used when monochrome printing is performed. Thus, when monochrome printing is performed, some of the plurality of heads used when color printing is performed are used. Therefore, “switching from color printing to monochrome printing” at the replacement of the roll paper corresponds to “replacement of the wide paper 61 with the narrow paper 62” in the first embodiment, and “switching from monochrome printing to color printing” at the replacement of the roll paper corresponds to “replacement of the narrow paper 62 with the wide paper 61” in the first embodiment.
When color printing is switched to monochrome printing at the replacement of the roll paper, the maintenance content determination process is executed in the same procedure as in the “replacement of the wide paper 61 with the narrow paper 62” in the first embodiment (cf.
When monochrome printing is switched to color printing at the replacement of the roll paper, the maintenance content determination process is executed in the same procedure as in the “replacement of the narrow paper 62 with the wide paper 61” in the first embodiment (cf.
When monochrome printing is switched to color printing at the replacement of the roll paper, the inspection pattern may be printed at the tail of the print paper for monochrome printing, which is the preceding print paper, using the C color head, the M color head, the Y color head, and the K color head. In this case, inspection patterns of C color, M color, Y color, and K color are formed on the print paper for monochrome printing. The configuration may be such that these inspection patterns are read and a head of a color requiring maintenance and the maintenance content for a head of a color requiring maintenance are determined based on the read result of the inspection pattern. By performing such control, it is possible to determine the need for maintenance of each head and the content of the maintenance on the basis of the criterion suitable for printing on the subsequent print paper during a period in which printing on the preceding print paper is performed. Therefore, it is possible to reliably perform printing with high print quality from the head part of the subsequent print paper.
As above, according to the present modification as well, in the inkjet printing apparatus 10 having the auto-splice function, when the roll paper is replaced, suitable maintenance is performed taking into account the print process scheduled to be executed after the replacement.
Note that, although the second modification relates to a case where switching is made between color printing and monochrome printing at the replacement of the roll paper, the same control can be adopted for a case where switching is made between printing using a spot color head and printing not using a spot color head at the replacement of the roll paper. For example, when normal color printing not using a spot color is switched to color printing using spot color, an inspection pattern is printed at the tail of print paper for normal color printing, which is the preceding print paper, by using the heads of normal C, M, Y, and K colors and the head of the spot color that is used on the subsequent print paper. The configuration may be such that the inspection patterns of C, M, Y, and K colors and the spot color is read and a head of a color requiring maintenance and the maintenance content for a head of a color requiring maintenance are determined based on the read result.
In the inkjet printing apparatus, continuous printing based on a plurality of jobs may be performed. When continuous printing is underway, a plurality of jobs can be print targets in a period from when the roll paper is replaced to when the roll paper is replaced next. A criterion used at the time of determining the content of maintenance (the need for maintenance, inkjet head 241 to be a maintenance target, type of maintenance, etc.) may be defined for each job. In consideration of the above, an embodiment in which the criterion is defined for each job and continuous printing based on a plurality of jobs is executed will be described as a second embodiment.
In the present embodiment, at the time of determining the content of maintenance to be performed when the preceding roll paper is replaced with the subsequent roll paper regarding the roll paper to be used, the strictest criterion (a criterion for maximizing the number of inkjet heads 241 determined as maintenance targets) is used among the criteria defined for a plurality of jobs for which printing is performed before, regarding the roll paper to be used, the subsequent roll paper is further replaced with the next roll paper.
The overall configuration of the printing system, the configuration of the inkjet printing apparatus 10, the configuration of the printing unit 24, the configuration related to the auto-splice function, the hardware configuration of the print control device 100, the schematic functional configuration of the control unit 150, and the functional configuration related to maintenance are similar to those of the first embodiment, and hence the description thereof is omitted (cf.
Hereinafter, control of maintenance in the present embodiment will be described. Here, the focus is on maintenance that is performed at the time of a first replacement of the roll paper in a case where the first replacement of the roll paper is performed at time t1 and a second replacement of the roll paper is performed at time t2, as shown in
According to
With reference to a flowchart shown in
After the maintenance content determination process is started, first, the inspection result Dr for the inspection pattern printed at the tail of the preceding print paper is acquired (step S400).
Thereafter, job information JI related to a job group (a plurality of jobs) to be executed before the next replacement of the roll paper is acquired (step S410). Here, the job information JI related to the job group for which printing is scheduled to be performed in a period from when the first replacement of the roll paper is performed to when the second replacement of the roll paper is performed is acquired. That is, the job information JI related to job (C), job (D), and job (E) is acquired. Note that the job information JI includes information such as printing conditions.
Next, the level of the criterion for each job is acquired based on the job information JI, and the maximum level among the acquired levels is specified (step S420). Here, the level of the criterion for each of job (C), job (D), and job (E) is acquired, and 3, which is the level of the criterion for job (D), is specified as the maximum level.
Next, it is determined whether or not maintenance is necessary (step S430). Specifically, based on the inspection result Dr acquired in step S400, it is determined, for example, whether or not maintenance of the inkjet head 241 used at the time of printing based on each of job (C), job (D), and job (E) is necessary in accordance with the criterion for job (D). As a result, when it is determined that maintenance is necessary, the process proceeds to step S440. On the other hand, when it is determined that maintenance is not necessary, it is determined not to perform maintenance, and the maintenance content determination process ends.
In step S440, the inkjet head 241 to be a maintenance target is specified. For example, the inkjet head 241 having a defect among the inkjet heads 241 used at the time of printing based on job (C), job (D), and job (E) is set as a maintenance target.
Thereafter, based on the inspection result Dr acquired in step S400, it is determined whether or not cleaning is necessary for the inkjet head 241 that is a maintenance target in accordance with the criterion for job (D). As a result, when it is determined that cleaning is necessary, the process proceeds to step S452, and when it is determined that cleaning is not necessary, the process proceeds to step S454. When it is determined that cleaning is not necessary, flushing is performed.
In step S452, the cleaning intensity is determined similarly to step S272 of
According to the present embodiment, in the inkjet printing apparatus 10 having an auto-splice function, when the splicer 213 replaces the roll paper to be used, the maintenance content control unit 151 determines the inkjet head 241 to be a maintenance target in accordance with the strictest criterion among the criteria defined for a plurality of jobs for which printing is scheduled to be performed before the next replacement of the roll paper. Accordingly, when the roll paper is replaced, maintenance is performed on the inkjet head 241 depending on the print process performed after the replacement. As above, similarly to the first embodiment, according to the present embodiment, the inkjet printing apparatus 10 is achieved that has the auto-splice function and is capable of performing, when the roll paper is replaced, suitable maintenance taking into account the print process scheduled to be executed after the replacement.
The present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention. For example, although either cleaning or flushing is performed as maintenance of the printing unit 24 in each of the above embodiments, the present invention is not limited thereto, and both cleaning and flushing may be performed as maintenance of the printing unit 24.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-134203 | Aug 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/027592 | 7/13/2022 | WO |
