JP2002254672A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obviate exchange of an ink cartridge when a nozzle of the cartridge is clogged, preventing missed dot effectively and reducing the amount of ink consumption in the ink jet printer. SOLUTION: The ink jet printer is provided with a main ink cartridge and a subordinate ink cartridge. When the main ink cartridge nozzle is clogged (#2), the clogging is detected and the nozzle number is registered (#4). When the number of the nozzle clogged has a dot, the nozzle corresponding to the other subordinate ink jet head for the dot is driven to print at the proper timing so as to eject an ink liquid drop at the original dot position (#5).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer used by being connected to a personal computer or the like, and more particularly, to a measure against clogging of nozzles of an ink jet head.

[0002]

2. Description of the Related Art Conventionally, in an ink-jet printer, if a nozzle of a recording head is clogged, ink cannot be ejected and print quality deteriorates. Therefore, the entire ink cartridge including the recording head has been replaced. In this case, even if some of the nozzles are clogged, the entire ink cartridge is replaced, so that there is much waste. Therefore,
Even if the nozzles are clogged, there is known a technique for increasing the amount of ink ejected from the nozzles adjacent to the clogged nozzles without replacing the recording head, thereby making the drop of ink droplets less noticeable (for example, See JP-A-9-24609).

In order to prevent nozzle clogging when an ink jet printer is left without being used for a long time, there is a type in which ink is sucked out by vacuum from the nozzle surface to perform cleaning. As the cleaning is performed, the ink consumption increases. Therefore, there is known a technique of using a head having a plurality of nozzle groups, operating each nozzle group at a different timing from each other, printing the same bit image at the same dot position in a superimposed manner, and preventing the occurrence of dot removal. For example, see JP-A-8-187843.

[0004]

However, in the printer disclosed in Japanese Patent Laid-Open No. 9-24609 described above, it is only necessary to make the drop of ink droplets inconspicuous and to adjust the dot position of the clogged nozzle. In order to perform dot ejection, it is necessary to feed the sheet and then perform dot ejection, which takes time. Also, JP-A-8-18784
In a printer such as that disclosed in Japanese Patent Publication No. 3 (1993), the consumption of ink is still large due to overlap printing, and a printed image is shifted due to clogging.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and comprises a main ink cartridge and a subordinate ink cartridge. When a main ink cartridge nozzle is clogged, the main ink cartridge responds to the nozzle. By ejecting ink from the subordinate ink cartridge nozzles, it is possible to prevent dot dropout without wasting without replacing the ink cartridge when the nozzle is clogged,
It is an object of the present invention to provide an ink jet printer capable of reducing ink consumption.

[0006]

According to a first aspect of the present invention, at least two ink cartridges having an ink jet head having a plurality of nozzles arranged in a vertical direction are provided on a recording medium. A head which is mounted side by side in a traveling direction on a carriage which travels in a lateral direction, and which is driven to eject ink droplets from the nozzles toward a recording medium based on bit image data output from a print data processing means. An ink jet printer having a driving unit and an operation mode for printing a check pattern for inspecting nozzle clogging.
The two inkjet heads have the same function and are in a master-slave relationship. The print data processing means is constituted by a personal computer connected to a printer and controlling the printer. The user determines which nozzle has been clogged based on the printing result of the above, and registers the clogged nozzle number in the print data processing means, and the print data processing means has the registered clogged nozzle number. When the nozzle number has a dot, bit image data is generated for the dot so as to drive the corresponding nozzle of the other subordinate inkjet head, and the head driving unit outputs a bit output from the print data processing unit. Not clogged based on image data The dot for the nozzle is used for the main ink jet head, and the dot for the registered clogged nozzle is used for the corresponding nozzle of the other sub ink jet head so that ink droplets are ejected to their original dot positions. It is driven by taking.

In the above configuration, at least two ink jet heads provided with a plurality of nozzles in the vertical direction are provided.
And the ink jet heads are arranged side by side in the running direction of the carriage, and the respective ink jet heads have the same function as each other and are in a master-slave relationship. The user determines which nozzle has been clogged based on the print result of the check pattern by the main inkjet head, and registers the determined nozzle number in the print data processing means constituted by the personal computer. When the registered clogged nozzle number has a dot, the print data processing means creates bit image data so as to drive the corresponding nozzle of the other subordinate inkjet head for that dot. Based on the bit image data output from the print data processing means, the head driving means uses the main ink jet head for the dots of the nozzles that are not clogged and the sub ink jet head for the nozzle numbers that are registered with the clogging. Are respectively driven to eject ink droplets at a timing such that the ink droplets are ejected to the original dot positions. By switching the drive head to the recording of clogged dots in this way, there is no waste of replacing the entire ink cartridge even if some nozzles are clogged. In addition, since the printing is not the overlapping printing, the ink consumption does not increase.

According to a second aspect of the present invention, at least two ink cartridges each having an ink jet head in which a plurality of nozzles are arranged in a vertical direction travel on a carriage which travels laterally with respect to a recording medium. An ink jet printer comprising: head drive means mounted in a line in a direction, and driven to eject ink droplets from the nozzles toward a recording medium based on bit image data output from print data processing means. It is determined which nozzle of the ink jet head is clogged, and the clogged nozzle number is registered in the print data processing means, and the head driving means controls the bit image data output from the print data processing means. If the registered clogged nozzle number has a dot based on the For the corresponding nozzles of the other ink-jet head, in which ink droplets to the original dot positions to drive timed so it ejected.

In the above arrangement, two ink cartridges each having an ink jet head are mounted side by side in the running direction of the carriage, and it is determined which nozzle of one ink jet head is clogged. The registered nozzle number is registered in the print data processing means. When the clogged nozzle number has a dot based on the bit image data output from the print data processing unit, the head driving unit moves the corresponding nozzle of the other inkjet head to the original dot position for that dot. Driving is performed with a timing so that ink droplets are ejected. By switching the drive head to the recording of clogged dots in this manner, there is no waste of replacing the entire ink cartridge even if some nozzles are clogged as described above. In addition, since the printing is not the overlapping printing, the ink consumption does not increase.

[0010] Further, the invention described in claim 3 is based on claim 2.
In the inkjet printer described in 2, the two ink cartridges mounted on the carriage are assumed to have the same function, and when the ink cartridge is replaced between black and color having different numbers of dots of the inkjet head, The print data processing means recognizes the mounted cartridge and switches the operation of ejecting ink droplets to the head driving means.

In the above configuration, the two ink cartridges mounted on the carriage use the same color or the same black, but when the color cartridge is replaced with the black cartridge, the two ink cartridges are mutually replaced before and after the replacement. Even if the number of dots differs, the print data processing means recognizes the change and switches the ink ejection operation to the head driving means, so that the occurrence of missing dots does not occur.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet printer according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a control configuration of the ink jet printer. An inkjet printer 1 (hereinafter, referred to as a printer) includes an ASIC 2 (head driving unit) as a printer control circuit and a head driver 3 (head driving unit).
And two ink cartridges 4 (here, C1 and C2 which have the same function and are in a master-slave relationship), a carriage drive driver 5, and a paper feed unit 6 for transporting paper as a recording medium. . The printer 1 is connected to a personal computer 11 (hereinafter, referred to as a personal computer, which corresponds to print data processing means) via a printer cable 12.
The printing operation is controlled based on a user's instruction to a printer driver (application software) mounted on the personal computer 11.

The ASIC 2 receives printer control data and print data (bit image data) output from the personal computer 11, and outputs a control signal to each section of the printer. The ink cartridges 4 (C1, C2) are connected to the head driver 3 via an FPC, and are mounted on a carriage that travels in a lateral direction with respect to the paper, in a running direction. Each of these ink cartridges 4 has an ink jet head in which an ink tank and a plurality of nozzles are arranged in a vertical direction. The inkjet head has a piezoelectric element for ejecting ink corresponding to each nozzle.
The ASIC 2 outputs a drive signal for ejecting ink droplets from the corresponding nozzle of the inkjet head toward the paper to the head driver 3 based on the bit image data output from the personal computer 11.

The printer 1 controls the drive of one of the main ink cartridges 4 (C1), the carriage drive driver 5 and the paper feed unit 6 at a predetermined timing based on the printer control data and print data from the personal computer 11 in a normal state. Then, a printing operation is performed. Further, the printer 1 has an operation mode for printing a check pattern for inspecting clogging of the nozzles of the inkjet head, and determines which nozzle is clogged based on the printing result of the check pattern by the main inkjet head. Is determined by the user's judgment.

FIG. 2 shows a nozzle configuration of an ink jet head in two ink cartridges 4 (C1, C2) provided side by side. Here, a color ink cartridge is shown, and a plurality of nozzles (numbers 1, 2, 3,...) For cyan, magenta, and yellow are vertically arranged. Actually, a large number of nozzles are provided in a staggered manner (not shown) in order to increase the printing resolution. The arrow is
2 shows the traveling direction of the head. In the case of color printing, paper is fed (perpendicular to the arrow) for each color printing, and three colors are printed on the same line.

FIG. 3 shows an example of a check pattern. A check pattern is printed for each nozzle (numbers 1, 2, 3,...). In this example, black dots (numbers 1, 2, 4,
5) shows a dot printed normally, and a white dot (No. 3) shows a dot missing due to nozzle clogging. By checking the check pattern, the clogged nozzle number of the ink cartridge 4 (C1) is determined, and this is registered in the printer driver of the computer 11. By this registration, when the clogged nozzle number registered in the print data has a dot, the printer driver of the bass computer 11 drives the corresponding nozzle of the other subordinate inkjet head 4 (C2) for that dot. Create bit image data.

Based on the bit image data output from the personal computer 11, the ASIC 2 outputs a drive signal to the head driver 3 for ejecting ink droplets from the corresponding nozzle of the ink jet head toward the paper. In other words, dots for nozzles that are not clogged indicate the main inkjet head, and dots for registered clogged nozzles indicate the corresponding nozzles of the other subordinate inkjet head. Drive with timing so that it is ejected. The timing of driving the corresponding nozzle of the secondary inkjet head is as shown in FIG.
It is determined from the distance d between the two nozzle group rows and the traveling speed of the carriage.

FIG. 4 shows a schematic operation procedure of the printer 1. If the nozzle of the cartridge C1 is clogged during the normal printing operation (# 1) (YE
S), maintenance / nozzle check is performed (# 3).
This nozzle check is performed by printing a check pattern as shown in FIG. Register the clogged nozzle number found from the check pattern printing in the personal computer 11 (#
4) Dots other than the registered nozzles are in the cartridge C
One nozzle is used for printing, and the registered nozzle dots are printed using the corresponding nozzle of the cartridge C2 (#
5).

Since the drive head is switched to the recording of clogged dots by such an operation, the waste of replacing the entire ink cartridge as in the prior art even if some of the nozzles are clogged is eliminated. Disappeared,
Since overprinting is not performed, ink consumption does not increase.

FIGS. 5A and 5B show examples of other combinations of two ink cartridges having the same function used in the present invention. (A) is a combination of black ink cartridges B1 and B2, and (b) is a combination of a total of four cartridges of two color ink cartridges C1 and C2 and two black ink cartridges B1 and B2. Is shown. In the example of (a), when dot missing occurs in one cartridge in black printing, the dot is recorded in the other cartridge. Also,
In the example of (b), the above-described dot missing can be prevented both in black printing and color printing.

Further, the two ink cartridges mounted on the carriage are assumed to have the same function (colors or blacks), but the number of dots of the head is generally different between black and color (for example, Black 2
6, color 24). Therefore, when the cartridge is changed from color to black, the printer driver of the personal computer 11 recognizes the cartridge mounted on the carriage and switches the ink droplet ejection operation to the printer 1. As a result, when two ink cartridges mounted on the carriage are replaced, even if the number of dots differs before and after the replacement, the ink ejection operation is performed normally and dot missing may occur. Is gone.

The present invention is not limited to the configuration of the above-described embodiment, and various modifications are possible. For example, nozzle clogging detection can be performed by visually recognizing which nozzle is clogged based on a print result of a check pattern by an ink jet head, and the check pattern print result can be obtained by a separate image scanner. The missing dot may be detected by reading and image processing, and the nozzle number may be automatically determined.

[0023]

As described above, according to the ink jet printer of the first aspect of the present invention, it is determined which nozzle is clogged based on the print result of the check pattern by the main ink jet head, and the nozzle is determined. By registering the number in the print data processing means, when the registered clogged nozzle number has a dot, the corresponding nozzle of the subordinate inkjet head is driven for that dot, and the ink droplet is moved to the original dot position. The ink droplets are ejected at a timing so that the ink droplets are ejected.
There is no waste of replacing the entire ink cartridge even if some of the nozzles are clogged. Further, since overprinting is not performed, the consumption of ink does not increase.

According to the ink jet printer of the second aspect, it is determined which nozzle of one of the ink jet heads is clogged, and the clogged nozzle number is registered in the print data processing means. When the clogged nozzle number has a dot, the corresponding nozzle of the other ink jet head is driven with a timing so that the ink droplet is ejected to the original dot position for that dot. In addition, there is no loss of dots, and there is no waste of replacing the entire ink cartridge even if some of the nozzles are clogged. There is no increase in consumption.

According to the ink jet printer of the third aspect of the invention, when two ink cartridges mounted on the carriage are exchanged from color to black, the number of dots differs before and after the exchange. Since the print data processing means recognizes this and switches the ink ejection operation, a normal print operation is maintained.

[Brief description of the drawings]

FIG. 1 is a control configuration diagram of an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a diagram showing a nozzle arrangement of a head of an ink cartridge in the printer.

FIG. 3 is a diagram illustrating a print example of a check pattern.

FIG. 4 is a flowchart showing an operation procedure of the printer.

FIG. 5 is a diagram showing an example of a combination of ink cartridges.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet printer 2 ASIC (head drive means) 3 Head driver (head drive means) 4 Ink cartridge (C1, C2) 5 Carriage drive driver 11 Personal computer

Claims (3)

[Claims] At least two ink cartridges each having an ink jet head having a plurality of nozzles arranged in a vertical direction are mounted side by side in a traveling direction on a carriage which travels in a lateral direction with respect to a recording medium, and print data is provided. A head drive unit for driving the nozzles to eject ink droplets toward a recording medium based on bit image data output from a processing unit; and an operation mode for printing a check pattern for inspecting nozzle clogging. In the inkjet printer, the at least two inkjet heads have a function equivalent to each other and are in a master-slave relationship, and the print data processing means is configured by a personal computer connected to a printer and controlling the printer, Check pattern by one main inkjet head The user determines which nozzle has been clogged based on the printing result of the nozzle, and registers the clogged nozzle number in the print data processing means. When the selected nozzle number has a dot, bit image data is generated for that dot so as to drive the corresponding nozzle of the other subordinate inkjet head, and the head driving unit is output from the print data processing unit. Based on the bit image data, the dots for the nozzles that are not clogged indicate the main ink jet head, and the dots for the registered clogged nozzles indicate the corresponding nozzles of the other sub ink jet head. Timed so that ink droplets are ejected to the Inkjet printer characterized by. 2. At least two ink cartridges each having an ink jet head in which a plurality of nozzles are arranged in a vertical direction are mounted side by side in a running direction on a carriage which runs in a transverse direction with respect to a recording medium, and print data is printed. An ink jet printer comprising a head driving means for driving an ink droplet from a nozzle toward a recording medium based on bit image data output from a processing means, wherein one of the nozzles of the one ink jet head is It is determined whether or not the clogging is performed, and the clogged nozzle number is registered in the print data processing unit. The head driving unit is configured to register the registered clogging based on the bit image data output from the print data processing unit. If the selected nozzle number has a dot, the other ink jet Toheddo corresponding ink jet printer nozzle, ink drops to the original dot positions and drives timed so ejected. 3. The printing apparatus according to claim 2, wherein the two ink cartridges mounted on the carriage have the same function, and when the ink cartridge is replaced between black and color having different numbers of dots of an ink jet head, the printing is performed. 3. The ink jet printer according to claim 2, wherein the data processing unit recognizes the mounted cartridge and switches an ink droplet ejection operation to the head driving unit.