JP2003159785A - Ink jet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress images printed on a printing medium from being deteriorated due to abnormality in a printing section. <P>SOLUTION: In a flushing operation of a printing head 11, a flushing image 50 is printed on a paper 2 by ink ejected from every ejection nozzle 15. When the flushing image 50 is read by a read head 6a, and after confirmation that no generation of clogging has been occurred in every ejection nozzle 15, the print operation for an image 60 starts based on a print signal. While, when at least one of the ejection nozzles 15 is clogged, printing is stopped for performing cleaning of the print head 11. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet printer that prints an image on a long print medium that is conveyed.

[0002]

2. Description of the Related Art Ink jet printers print by spraying liquid ink onto paper. An inkjet printer has a print head in which a plurality of discharge nozzles for discharging ink are arranged, and printing is performed while the print head reciprocates in a direction perpendicular to the paper conveyance direction. Is common.

In the print head of such an ink jet printer, if printing is not performed (ink is not ejected) and left for a long time, ink near the opening of the ejection nozzle is dried and clogging occurs. Sometimes. Therefore, when printing is not performed for a long time, the opening of the discharge nozzle is often sealed with a cap or the like. However, even if it is left in a sealed state for a long time, the viscosity of the ink near the opening of the discharge nozzle gradually increases, making it impossible to start printing immediately, or the image to be printed will not be printed. It may get worse.

Further, in an ink jet printer capable of printing a color image, even when printing is continuously performed for a long time, an ejection nozzle that ejects the ink frequently and an ink that ejects the ink very often depending on the color of the ink. There is an ejection nozzle that is not ejected, and new ink is sequentially supplied near the opening of the ejection nozzle where ink is ejected frequently, so clogging is less likely to occur, but near the opening of the ejection nozzle where ink is not ejected very often. Is difficult to be supplied with new ink, and the ink is likely to be dried and clogged.

Therefore, in order to solve the problem that the image is deteriorated due to the clogging of the ejection nozzles, ink is forcibly ejected from the respective ejection nozzles regardless of printing, and the viscosity in the vicinity of the openings of the ejection nozzles is increased. The cleaning operation of the print head such as the flushing operation for discharging the ink that has become very high and the wiping operation for removing the ink with high viscosity from the vicinity of the opening of the discharge nozzle by wiping the vicinity of the opening of the discharge nozzle etc. There are many.

In a large ink jet type printer, the ink ejected from a plurality of ejection nozzles during the flushing operation is monitored by using laser light, so that the ejection nozzles are not clogged (printing). There is a device provided with a dot dropout detection device for detecting that a dot dropout does not occur in an image).

[0007]

As described above, it is possible to reduce the frequency of occurrence of clogging of the discharge nozzles by performing the cleaning operation of the print head as needed. However, if the ejection nozzles are still clogged after the print head cleaning operation, the ejection nozzles are clogged until the image actually printed on the paper is visually confirmed. It is difficult to notice (print head abnormality). Therefore, when the abnormality in the print head is noticed after the printing is started and the large amount of printing is already performed, it takes a lot of time and cost to perform the printing again.

Further, in such an ink jet type large size printer, the provision of the dot dropout detecting device causes the size of the device to be increased and the manufacturing cost of the printer device to be remarkably increased. Furthermore, if the dot dropout detection device monitors the ink ejected from the ejection nozzles during the flushing operation, the print head is once displaced from the printable area in order to confirm that the ejection nozzles are not clogged. Often they have to move to different positions. Therefore, the processing capability of the printer is reduced as much as the print head is moved to a position deviated from the printable area.

Therefore, a main object of the present invention is to provide an ink jet printer capable of suppressing deterioration of a print image printed on a print medium due to an abnormality of a printing section.

[0010]

In order to achieve the above-mentioned object, an ink jet printer according to a first aspect of the present invention comprises a conveying means for conveying a print medium, and an ink for the print medium conveyed by the conveying means. A printing unit for printing a confirmation image formed by ejecting ink from the plurality of ejection nozzles and a print image based on print data, and a surface of a print medium. A reading unit arranged downstream of the printing unit for reading, and a state detection unit for detecting a state of the printing unit based on data corresponding to the confirmation image read by the reading unit. It is characterized by having.

According to the first aspect, it is possible to detect the state of the printing unit, such as whether or not there is an abnormality in the printing unit, based on the confirmation image printed on the printing medium by the printing unit. Therefore, it is possible to prevent the processing capacity of the printer from being lowered in order to check the state of the printing unit.
Furthermore, a separate device for checking the state of the printing unit is not required. As a result, it is possible to prevent the printer device from increasing in size and suppress an increase in manufacturing cost for the printer device.

Further, the ink jet printer according to a second aspect of the present invention is such that the print medium is a long member, and further comprises a cutting unit arranged downstream of the reading unit for cutting the print medium. It is characterized by that.

According to a second aspect of the present invention, after the confirmation image and the print image are continuously printed on a long print medium, an area other than the area corresponding to the print image (the area corresponding to the confirmation image) It is possible to prevent the print medium from being wasted because it can be cut and discarded.

Further, in the ink jet printer according to a third aspect of the present invention, the printing unit starts printing the print image on the printing medium when the state detecting unit detects that the state of the printing unit is normal. Is further provided with a control means for controlling.

According to the third aspect, after it is confirmed that there is no abnormality in the printing unit, the printing of the print image on the printing medium is started. Therefore, the printing image is printed on the printing medium due to the abnormality. It is possible to suppress deterioration of the printed image. Therefore, due to the abnormality of the printing unit, the situation in which the printing has to be performed again hardly occurs.

Further, in the ink jet printer according to a fourth aspect of the present invention, when the control unit detects that the state of the printing unit is abnormal by the state detection unit, the printing of the image on the print medium is stopped. The printing unit is controlled as described above.

According to the fourth aspect, when it is confirmed that there is an abnormality in the printing section, the printing of the print image on the printing medium is stopped, so that a misprint (printing in a state where the printing section has an abnormality) occurs. It is possible to prevent the print medium from being wasted.

Further, the ink jet printer according to a fifth aspect is characterized in that the confirmation image is formed by ejecting ink from all of the plurality of ejection nozzles by a flushing operation in the printing section. It is a thing.

According to the fifth aspect, during the flushing operation in the printing section, the state of the printing section is confirmed based on the confirmation image printed on the print medium by ejecting ink from all the ejection nozzles. As a result, misprinting due to an abnormality in the printing unit rarely occurs.

Further, the ink jet printer according to claim 6 is characterized in that the reading section is provided so as to be close to the printing section. Claim 6
According to the above, since the printing of the print image is started from the area close to the area of the print medium on which the check image is printed, the print image is conveyed along the conveyance direction of the print medium between the check image and the print image on the print medium. The distance in the direction can be reduced. Therefore, it is possible to prevent the print medium and the ink from being wasted. When the printing unit can reciprocate in a direction perpendicular to the print medium conveyance direction, the reading unit can be downsized by moving the reading unit together with the printing unit. The configuration of the reading unit can be simplified and the manufacturing can be performed at low cost.

Further, in the ink jet printer according to a seventh aspect of the invention, when the control means prints a plurality of print images continuously on the print medium, before printing of each print image is started. In addition, the printing unit is controlled so that the confirmation image is printed without fail.

According to the seventh aspect, since it is confirmed that there is no abnormality in the printing section immediately before each of the plurality of print images is printed, the print image printed on the print medium due to the abnormality of the printing section is The deterioration can be suppressed more effectively. When an abnormality occurs in the printing unit, the print image of the print image on the print medium is printed before the printing of the next print image is started (when the print image being printed is finished when the abnormality occurs in the print unit). Since printing is stopped, it is possible to effectively prevent the print medium from being wasted due to misprinting.

Further, in the ink jet printer of the eighth aspect, the printing unit is capable of reciprocating in a direction perpendicular to the conveying direction of the print medium, and the control means prints the confirmation image on the print medium. The printing unit is controlled so that the printing image and the printing medium are printed at positions adjacent to each other along a direction perpendicular to the conveyance direction of the printing medium.

According to the eighth aspect of the present invention, the printing unit reciprocates in the direction perpendicular to the print medium conveyance direction and continuously prints the print image and the confirmation image along the direction perpendicular to the print medium conveyance direction. Therefore, the state of the printing section can be confirmed in real time based on the confirmation image. Therefore, when an abnormality occurs in the print unit, the printing of the print image on the print medium is immediately stopped even during the printing of the print image, so that the print medium is more effectively prevented from being wasted due to misprinting. Can be suppressed.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an inkjet printer according to the first embodiment.

Ink jet printer 1 shown in FIG.
Is a substantially rectangular parallelepiped housing 30 and includes a carrier table 4, an inkjet printing unit 5, an image reading unit 6, a cutting unit 7, a carrier roller unit 8, a pressure roller unit 9, and a discharge roller unit 10. have. In the housing 30, a winding portion 2a wound in a roll shape.
A long sheet 2 on which is formed is arranged. The winding portion 2a of the paper 2 is held by a drum 3 which is rotatable around an axis center. Further, as will be described later, the operation of each part of the inkjet printer 1 is controlled by the controller 20 arranged in the housing 30.

The transport roller unit 8 is the controller 2
The drive roller pair is driven by a motor 25 controlled by 0, and is for conveying the sheet 2 before being cut by the cutting unit 7. That is, the transport roller unit 8 unwinds the paper 2 from the winding portion 2 a, transports it on the transport base 4 to the downstream side, and sequentially passes the inkjet printing unit 5, the image reading unit 6, and the cutting unit 7. Since the paper 2 conveyed between the image reading unit 6 and the cutting unit 7 is nipped by the pressure roller unit 9, the inkjet printing unit 5 prints an image, the image reading unit 6 reads and cuts the image. It is possible to properly cut the sheet 2 by the unit 7.

The ink jet printing unit 5 includes a print head 11 and a carriage 12 that holds the print head 11.
And a suction fan 13. Print head 11
Is equipped with a large number of ejection nozzles 15 (see FIG. 3) capable of ejecting color inks such as yellow (yellow), magenta (magenta), cyan (blue-green), and black. Therefore, the print head 11 is based on the signal from the controller 20, and the surface of the conveyed paper 2 (see FIG. 1).
Then, a desired color image can be printed by ejecting color inks from a large number of ejection nozzles 15 toward the upper surface). The number and arrangement of the discharge nozzles 15 can be changed arbitrarily. The print head 11 may have a discharge nozzle that discharges only black ink, and may print a black and white image.

The ink jet printing unit 5 is
Liquid ink is ejected from the nozzles dot by dot to print on the paper 2, and any of a piezo jet system, a thermal jet system, or any other system may be adopted.

Further, in the print head 11 of the ink jet printing unit 5, the discharge nozzle 1 is used during printing.
In order to prevent clogging of the sheet 5, the flushing operation is appropriately executed. In the flushing operation of the print head 11, as described above, a predetermined amount of ink is forcibly ejected onto the paper 2 from all the ejection nozzles 15 regardless of printing. Therefore, a predetermined amount of ink is ejected from all the ejection nozzles 15 as well as the highly viscous ink in the vicinity of each opening of the ejection nozzles 15, and a flushing image is printed on the paper 2.

Here, the flushing image is printed by ejecting ink from all the ejection nozzles 15 by the flushing operation, but the inks ejected from the respective ejection nozzles 15 should not overlap each other on the paper 2. Is ejected. Therefore, for example, when a part of the discharge nozzle 15 is clogged, the discharge nozzle 1
No ink is ejected from the sheet 5, and the ink does not land on the position corresponding to the ejection nozzle 15 on the sheet 2, so that a blank is formed in the area on the sheet 2 where the flushing image is printed. It will be. In addition, the discharge nozzle 15
Even if some of the ink is starting to become clogged but is not completely clogged until no ink is ejected,
Since the amount of ink ejected from the ejection nozzles 15 is reduced, a blank is formed in the area on the paper 2 where the flushing image is printed. In this way, the clogging state of the ejection nozzles 15 of the print head 11 can be known from the flushing image printed on the paper 2 by the flushing operation of the print head 11.

The flushing operation of the print head 11 may be performed, for example, only at the start of printing, or may be performed every fixed number of shots (the number of times ink is ejected from each ejection nozzle 15). It may be omitted or may be performed every time a predetermined number of images are formed, and is preferably set in accordance with print conditions. Further, similarly, it is preferable that the amount of ink ejected from each ejection nozzle 15 and the number of shots during the flushing operation are also set in accordance with printing conditions.

The carriage 12 can reciprocate together with the print head 11 in a direction perpendicular to the paper 2 conveyance direction.
Therefore, the print head 11 ejects ink toward the surface of the paper 2 while reciprocating in the direction perpendicular to the transport direction of the paper 2. The suction fan 13 is arranged at a position facing the print head 11 with the conveyance path of the sheet 2 interposed therebetween, and sucks the sheet on the conveyance table 4 through an opening (not shown) formed in the conveyance table 4. It is for. Therefore, the sheet 2 facing the print head 11 is conveyed in close contact with the conveyance table 4 by being sucked by the suction fan 13 arranged on the back side (lower surface in FIG. 1) of the sheet 2 and the print head 11. The intervals are fixed. This is because when the paper 2 is curled, a part of the paper 2 is largely separated from the transport table 4 to suppress the occurrence of printing defects due to a change in the distance from the print head 11.

The image reading unit 6 is provided with a reading head 6a which is a linear optical sensor having a width equal to or larger than the width of the paper 2, and is provided between the ink jet printing unit 5 and the pressure roller unit 9. It is located in. The inkjet printing unit 5 and the image reading unit 6 are preferably arranged as close as possible to each other. Then, the image reading unit 6 can continuously read the surface of the printed paper 2 that has been conveyed to the reading position facing the reading head 6a. Then, the data read by the image reading unit 6 is continuously supplied to the controller 20. Note that the reading of the surface of the paper 2 by the image reading unit 6 does not necessarily have to be performed continuously, and may be changed within a range in which the same function as that of the present embodiment can be obtained, for example, intermittent reading is performed. You can

The cutting unit 7 is a moving blade 7 arranged on the same side of the paper 2 as the ink jet printing unit 5.
It has a and a fixed blade 7b arranged so as to face the movable blade 7a with the sheet 2 in between. Both the fixed blade 7b and the movable blade 7a are rectangular blades having a width slightly larger than the width of the paper 2. The moving blade 7a is a controller 20.
By the motor 27 controlled by the above, the printed sheet 2 that has been conveyed from the upstream side of the conveyance path can be moved toward and away from the fixed blade 7b. It is possible to cut along the width direction by the action. By cutting in this way, the printed paper 2 is divided into a predetermined length.

The discharge roller unit 10 is a pair of drive rollers driven by a motor 26 controlled by the controller 20. The discharge roller unit 10 conveys the printed sheet 2 cut by the cutting unit 7 and discharges it from the discharge port 30a. Let

The controller 20 performs a predetermined process on the image signal supplied from an input interface (not shown), and supplies a print signal containing image data corresponding to the image to be printed to the ink jet printing unit 5. Further, the controller 20 supplies a drive signal to the motors 25, 26, 27 and receives the image data read by the image reading unit 6.

The controller 20 is provided with hardware such as a CPU, ROM and RAM controlled by appropriate software, and has a clogging detection section 21 and a control section 2.
2 and.

Based on the image data corresponding to the flushing image supplied from the image reading unit 6, the clogging detection unit 21 determines whether or not each of the ejection nozzles 15 of the print head 11 is clogged (print head). It is possible to detect whether the discharge nozzles 15 of 11 are proper or not.

The control unit 22 can control the print head 11 to print the flushing image on the paper 2 by the flushing operation before starting the printing of the image. Further, when the clogging detection unit 21 determines that all the ejection nozzles 15 of the print head 11 are not clogged, the control unit 22 starts printing an image on the paper 2. The print head 11 can be controlled. On the other hand, if it is determined that at least one of the discharge nozzles 15 of the print head 11 is clogged, the cleaning operation of the print head 11 should be performed before the printing of the image on the paper 2 is started. You can The cleaning operation of the print head 11 may be performed automatically or manually.

Here, in the present embodiment, the print head 1
As the cleaning operation No. 1, the wiping operation of the print head 11 is performed. In the wiping operation of the print head 11, the viscous ink is removed from the vicinity of the opening of the ejection nozzle by wiping off the vicinity of the opening of the ejection nozzle with a rubber-like member or the like. As a result, the clogging of the discharge nozzle 15 is eliminated. The cleaning operation of the print head 11 is not limited to the wiping operation of the print head 11, and may be any operation as long as it has the same effect.

Therefore, as described above, the flushing operation of the print head 11 similar to that performed during the printing operation is performed by the flushing receiving portion (not shown) provided at the position where the print head 11 is displaced from the printable area. May be performed after being moved to a position opposite to. In this case, for example, the amount of ink or the number of shots forcibly ejected from the ejection nozzles is increased so that the clogging of the ejection nozzles 15 can be effectively eliminated as compared with the flushing operation performed during the printing operation. It is preferable.

Next, the printing operation of the ink jet printer 1 configured as described above will be described with reference to FIGS. 2 and 3. FIG. 2 is a flow chart showing the procedure of a printing operation in the inkjet printer of FIG. FIG. 3 is a diagram for explaining a printing operation in the inkjet printer of FIG.

First, when the leading end portion of the paper 2 unwound from the winding portion 2a by the conveying roller unit 8 is conveyed to a position facing the print head 11, the flushing operation of the print head 11 is performed in step S1. The flushing image 50 is printed (see FIG. 3A). Here, the flushing image 50 is printed by ejecting ink from all the ejection nozzles 15 arranged in the print head 11 so as not to overlap each other on the paper 2, as described above. Therefore, it is possible to confirm whether or not all of the plurality of ejection nozzles 15 are clogged.

Subsequently, when the sheet 2 is conveyed and the portion of the sheet 2 on which the flushing image 50 is printed is conveyed to the position facing the read head 6a of the image reading unit 6, the read head 6a is read in step S2.
The flushing image 50 is read by (FIG. 3).
(See (b)).

Then, in step S3, the clogging detection unit 21 determines, based on the flushing image 50 read by the reading head 6a in step S2,
It is determined whether or not the discharge nozzle 15 of the print head 11 is clogged. Then, when all the discharge nozzles 15 are not clogged (S3: YE
S), the process proceeds to step S4. On the other hand, if at least one of the discharge nozzles 15 is clogged, the process proceeds to step S6.

In this way, if it is confirmed in step S3 that all the ejection nozzles 15 are not clogged, the image 60 based on the print signal is printed in step S4.
The print operation is executed (see FIG. 3C).

When the printing of the image 60 is completed, it is determined in step S5 whether or not the image is the last image of a plurality of images to be continuously printed based on the print signal. Then, if it is not the last image (S5: NO), the process returns to step S1 and the same processing as described above is repeated. That is, when the printing of the image 60 is completed, the flushing image 51 is printed, and if it is confirmed that all the ejection nozzles 15 are not clogged based on the flushing image 51, the image 61 based on the print signal is displayed. The print operation is executed. By repeating such operations, the image 61 is printed, and then the flushing image 52, the image 62, and the flushing image 53 are printed in this order (see FIG. 3D). Then, when the printing of the last image of the plurality of images to be continuously printed based on the print signal is completed (S
5: YES), the process ends.

Here, in the present embodiment, the area where the flushing image (for example, the flushing image 50) is printed is the leading end of the sheet 2 or between the images to be printed (for example, the image 60 and the image 61). And between) and is included in a portion (discarded portion) that is later cut and discarded by the cutting unit 7. That is, when borderless printing is performed in the roll processing as in the present embodiment, the processing of cutting from both sides in the vicinity of the boundary line between the images to be printed adjacent to each other is performed. In the meantime, a part to be discarded is formed. Therefore, by utilizing the discarded portion as the area for printing the flushing image, it is possible to suppress the loss of the paper 2 and the loss of the processing capacity for printing the flushing image.

Further, in the present embodiment, margins are provided on both sides of the flushing image (between the flushing image and the image) so that the image is not contaminated by the ink ejected by the flushing operation of the print head 11. Although it is provided, the blank portion does not necessarily have to be provided.

On the other hand, if it is confirmed in step S3 that at least one of the discharge nozzles 15 is clogged, the cleaning operation of the print head 11 is executed in step S6. When the cleaning operation of the print head 11 is completed, the process returns to step S1.
The same processing as described above is repeated. In other words, by printing and reading the flushing image,
After it is confirmed by the cleaning operation of the print head 11 whether the clogging of the ejection nozzle 15 has been resolved,
When the clogging of the discharge nozzle 15 is cleared, the image is printed.

After that, the paper 2 is conveyed, and the paper 2 is conveyed every time the front end and the rear end of the image-printed portion of the paper 2 are conveyed to the position facing the moving blade 7a of the cutting unit 7. Is disconnected. Then, the cut sheet 2 between the images (including the portion where the flushing image is printed) is discarded.

As described above, according to the ink jet printer 1 of this embodiment, the ejection nozzles 15 of the print head 11 are clogged based on the flushing image printed on the paper 2 by the flushing operation of the print head 11. It is possible to confirm whether or not has occurred. Therefore, it is possible to prevent the processing capacity of the inkjet printer 1 from being lowered in order to confirm the state of the print head 11. Further, no separate device is required to check the state of the print head 11. As a result, the size of the inkjet printer 1 can be increased and the manufacturing cost of the printer device can be prevented from increasing.

Further, after the flushing image and the image are continuously printed on the long paper 2, only the region other than the region corresponding to the image (including the region corresponding to the flushing image) is cut. Since the paper 2 can be discarded, it is possible to prevent the paper 2 from being wasted.

In addition, there is no abnormality in the print head 11,
That is, after it is confirmed that the discharge nozzles 15 of the print head 11 are not clogged, the image printing on the paper 2 is started, and therefore the print head 11 is printed on the paper 2 due to an abnormality. It is possible to suppress deterioration of the displayed image. Therefore, due to the abnormality of the print head 11, the situation in which the printing has to be redone hardly occurs.

Also, there is an abnormality in the print head 11,
That is, when it is confirmed that the ejection nozzles 15 of the print head 11 are clogged, the printing of the image on the paper 2 is stopped, and therefore it is possible to prevent the paper 2 from being wasted due to misprinting. it can.

During the flushing operation of the print head 11, the state of the print head 11 is confirmed based on the flushing image printed on the paper 2 by ejecting ink from all the ejection nozzles 15. Therefore, misprinting due to the abnormality of the print head rarely occurs.

Further, the reading head 6a is provided so as to be close to the print head 11, and the image printing is started from the area close to the area of the paper 2 on which the flushing image is printed. It is possible to reduce the distance between the flushing image and the image in the direction along the conveyance direction of the sheet 2. Therefore, it is possible to prevent the paper 2 and the ink from being wasted.

Since it is confirmed that the print head 11 has no abnormality immediately before the plurality of images are printed, it is possible to prevent the image printed on the paper 2 from deteriorating due to the abnormality of the print head 11. It can be suppressed more effectively. When an abnormality occurs in the print head 11, the image is printed on the paper 2 before the printing of the next image is started (at the end of printing the image being printed when the abnormality occurs in the print head 11). Is canceled, it is possible to effectively prevent the paper 2 from being wasted due to misprinting.

Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 4 shows a second embodiment of the present invention.
It is a diagram showing a schematic configuration of an ink jet printer according to the embodiment of.

Here, a detailed structure of the ink jet printer 101 according to the second embodiment will be described with reference to FIG. Inkjet printer 1 of FIG.
01 differs greatly from the inkjet printer 1 of FIG. 1 in that the inkjet printer 1 is provided with an image reading unit 6 having a read head 6a which is a linear optical sensor having a width larger than the width of the paper 2. On the other hand, in the ink jet printer 101, a small reading head 106a is attached to the carriage 12 instead of the image reading unit 6, and the ink jet printer 1 cuts along the width direction of the paper 2. The inkjet printer 101 has a cutting unit 7 for cutting along the width direction of the paper 2 and a cutting unit 7 for cutting along the conveyance direction of the paper 2. The cutting unit 107 is provided. Since the other configurations are the same as those of the inkjet printer 1 of FIG. 1, the same reference numerals are given and the description thereof is omitted.

As shown in FIGS. 4 and 6, the carriage 12 of the ink jet printer 101 has a small reading head 106a adjacent to the ejection nozzle 15.
Is attached. The read head 106a is an optical sensor similar to the read head 6a, and its length is shorter than the length of the read head 6a. Therefore, the reading head 106a is conveyed to the reading position facing the reading head 106a while reciprocating along with the ejection nozzle 15 as the print head 11 reciprocates along the direction perpendicular to the conveying direction of the sheet 2. The surface of the printed paper 2 can be continuously read.

Further, the ink jet printer 101
Is a cutting unit 107 arranged on the downstream side of the cutting unit 7, and a conveyance unit arranged between the cutting unit 7 and the cutting unit 107 for supplying the paper 2 cut by the cutting unit 7 to the cutting unit 107. The roller unit 108 and the controller 20 for discharging the sheet 2 cut by the cutting unit 7 from the discharge port 30a.
A discharge roller unit 110 driven by a motor (not shown) connected to the
The discharge port 13 formed in the direction perpendicular to the transport direction of the paper 2 on the upstream side of 07 (in FIG. 4, the front direction perpendicular to the paper surface).
Paper 2 cut by the cutting unit 107 from 0a
And a discharge roller unit (not shown) driven by a motor (not shown) connected to the controller 20 for discharging.

The cutting unit 107 has a moving blade 107a disposed on the same side of the paper 2 as the ink jet printing unit 5 and a moving blade 107 with the conveyance path of the paper 2 interposed therebetween.
It has a fixed blade 107b arranged so as to face a. Here, the movable blade 107a and the fixed blade 107b
Together, the length of the image area printed on the paper 2 (see FIG.
The rectangular blade has a width slightly larger than that of the cutting unit 107, and is arranged along the conveyance direction of the sheet 2 on the upstream side of the cutting unit 107. The movable blade 107a and the fixed blade 107b are arranged on the upstream side of the cutting unit 107 on the outer side in the width direction of the conveyance path of the sheet 2 (the front side perpendicular to the paper surface in FIG. 4). The moving blade 107a can be moved toward or away from the fixed blade 107b by a motor 128 controlled by the controller 20, and the moving blade 107a is cut by the cutting unit 7.
Paper 2 with one image and one flushing image printed
Can be cut along the conveyance direction on the upstream side of the cutting unit 107 by the interaction with the fixed blade 107b. By being cut in this way, the printed paper 2 on which an image having a predetermined width is printed is divided.

In the vicinity of the discharge roller unit that conveys the sheet 2 in the direction perpendicular to the sheet 2 conveying direction on the upstream side of the cutting unit 107, a leading end position detection sensor (for detecting the leading end of the sheet 2 ( (Not shown) is disposed, and one end portion of the sheet 2 cut by the cutting unit 7 (the sheet at that time) while the sheet 2 is conveyed in a direction perpendicular to the conveying direction of the sheet 2 on the upstream side of the cutting unit 107. The position (corresponding to the leading end of the sheet 2 in the transport direction of 2) can be detected. Then, the controller 20 controls the cutting timing in the cutting unit 107 based on the leading edge of the sheet 2 detected by the leading edge position detection sensor.

Next, the operation of the ink jet printer 101 according to the present embodiment configured as described above will be described with reference to FIGS. 5 and 6. FIG. 5 shows FIG.
6 is a flowchart showing the procedure of a printing operation in the inkjet printer of FIG. FIG. 6 is a diagram for explaining a printing operation in the inkjet printer of FIG.

First, when the leading end of the sheet 2 unwound from the winding section 2a by the conveying roller unit 8 is conveyed to a position facing the print head 11, the flushing operation of the print head 11 is performed in step S11. The flushing image 150 is printed over the entire width of the paper 2. Here, like the flushing image 50, the flushing image 150 is printed by ejecting ink from all the ejection nozzles 15 arranged in the print head 11 so as not to overlap each other on the paper 2. Therefore, it is possible to confirm whether or not all of the plurality of ejection nozzles 15 are clogged.

Subsequently, the sheet 2 is conveyed, and the area of the sheet 2 on which the flushing image 150 is printed reciprocates in the direction perpendicular to the conveying direction of the sheet 2 and the reading head 10.
When it is conveyed to the position facing 6a, the flushing image 150 is read by the reading head 106a in step S12.

Then, in step S13, the clogging detector 21 detects the read head 1 in step S12.
Based on the flushing image 150 read by 06a, it is determined whether or not the discharge nozzle 15 of the print head 11 is clogged. If no clogging has occurred in all the discharge nozzles 15 (S
13: YES), and proceeds to step S14. On the other hand, if at least one of the discharge nozzles 15 is clogged, the process proceeds to step S18.

As described above, when it is confirmed in step S13 that all the ejection nozzles 15 are not clogged, the printing operation of the image 160 based on the print signal is executed in step S14 and As shown in FIG. 6, the flushing image 151 is printed at a position adjacent to the image 160 along the direction perpendicular to the transport direction of the sheet 2. That is, at this time, the reading head 106 is printed while the image 160 and the flushing image 151 are printed.
The printed flushing image 151 conveyed to the reading position is read by a.

In step S15, the clogging detection unit 21
In step S14, it is determined based on the flushing image 151 read by the reading head 106a whether or not the discharge nozzle 15 of the print head 11 is clogged. Then, when all the discharge nozzles 15 are not clogged (S15:
(YES), the process proceeds to step S16, and printing of the image 160 and the flushing image 151 is continued. On the other hand, if at least one of the discharge nozzles 15 is clogged, the process proceeds to step S18.

When the printing of the image 160 is completed,
In step S17, it is determined whether or not the image is the last image of a plurality of images to be continuously printed based on the print signal. If it is not the last image (S17: NO), the process returns to step S14,
The image 161 and the flushing image 153 are printed in the same manner as described above. Further, as in the present embodiment, when a blank space having a predetermined length is provided between images (for example, between the image 160 and the image 161, as shown in FIG. 6), the flushing image is displayed. The flushing image 152 is preferably printed between the 151 and the flushing image 153. In addition, between the images,
It is not always necessary to provide a blank portion having a predetermined length.

By repeating such operations, the image 161 and the flushing image 153 are printed, and then the flushing image 154, the image 162, and the flushing image 155 are printed in this order (FIG. 6).
reference). Then, when the printing of the last image of the plurality of images to be continuously printed based on the print signal is finished (S17: YES), the process is finished.

Here, in the present embodiment, the areas where the flushing images 150, 151 and the like are printed are the margins where the images are not printed, and the cutting units 7, 107 are later provided.
It is included in the part that is cut and discarded by. In the present embodiment, between the image and the flushing image (for example, between the image 160 and the flushing image 151).
Although the margin portion is provided in the above, the margin portion does not necessarily have to be provided.

On the other hand, in steps S13 and S15,
When it is confirmed that at least one of the ejection nozzles 15 is clogged, the cleaning operation of the print head 11 is executed in step S18. When the cleaning operation of the print head 11 is completed, step S
Returning to 11, the same processing as described above is repeated. That is, after the flushing image is printed and read, it is confirmed by the cleaning operation of the print head 11 whether the clogging of the ejection nozzle 15 has been eliminated, and then the clogging of the ejection nozzle 15 is eliminated. Prints an image and a flushing image. Since the cleaning operation of the print head 11 in step S18 is the same as that described in the first embodiment, the description thereof will be omitted.

Then, thereafter, the paper 2 is subsequently conveyed, and every time the front and rear ends of the portion of the paper 2 on which the image is printed are conveyed to the position facing the moving blade 7a of the cutting unit 7. The sheet 2 is cut along the width direction of the sheet 2. Further, the paper 2 on which one image and one flushing image cut by the cutting unit 7 are printed.
Is cut by the cutting unit 107 at one end portion in the width direction of the image, and the paper
Is cut along the transport direction of. Then, the sheet 2 including the portion where the flushing image is printed is discarded.

As described above, according to the ink jet printer 101 of this embodiment, the ejection nozzles 15 of the print head 11 are clogged based on the flushing image printed on the paper 2 by the flushing operation of the print head 11. It is possible to confirm whether or not has occurred. As a result, the same effect as that of the first embodiment can be obtained.

Further, the print head 11 can reciprocate in the direction perpendicular to the conveying direction of the paper 2, and the read head 10
By making 6a move with the print head 11, the read head 106a can be downsized, the structure of the reading unit can be simplified, and the manufacturing can be performed at low cost.

Further, since the print head 11 reciprocates in the direction perpendicular to the conveyance direction of the paper 2 and continuously prints the image and the flushing image along the direction perpendicular to the conveyance direction of the paper 2, the flushing image is printed. Print head based on 1
The state of the discharge nozzle 15 of No. 1 can be confirmed in real time. Therefore, the ejection nozzles 15 of the print head 11
If at least one of the sheets is clogged, the printing of the image on the paper 2 is immediately stopped even during the printing of the image, so that the waste of the paper 2 due to misprinting is suppressed more effectively. can do.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various design changes can be made within the scope of the claims. Is possible. For example,
In the above-described first and second embodiments, it is determined that the state of the print head is normal (not abnormal) by confirming that all ejection nozzles of the print head are not clogged. The case is explained,
Abnormalities of the print head include, for example, displacement of the ink landing positions in both directions (a gap occurs in the ejection nozzle).
Other than the clogging of the discharge nozzle such as. That is, in the above-described embodiment, when it is confirmed based on the flushing image that the state of the print head is not abnormal, the print head is free from clogging of the ejection nozzles and all other abnormalities. As described.

Further, in the above-described first and second embodiments, a long sheet is used as the print medium, but the present invention is not limited to this, and a predetermined length (predetermined size) is used in advance.
Paper cut into sheets may be used. In this case,
A cutting unit for cutting the sheet may not be provided. Further, as the print medium, thin plastic or the like can be used in addition to paper.

In the first and second embodiments described above, the print head is based on the flushing image formed by ejecting ink from all the plurality of ejection nozzles by the flushing operation of the print head. However, the confirmation image for detecting the state of the print head is not limited to this, and the state of the print head can be confirmed. Any image other than the flushing image may be used as long as it is possible. Therefore, the state of the print head may be confirmed based on the check pattern printed on the paper. Here, the check pattern includes, for example, a grid pattern including a large number of lines printed for each color in a rectangular range over the entire width of the paper. In other words, when the lines of each color of the check pattern are printed without omission, it can be confirmed that all of the plurality of ejection nozzles are not clogged.

Here, the flushing image and the check pattern do not necessarily need to be formed by ejecting ink from all of the plurality of ejection nozzles, and may be formed by ejecting ink from a part of the plurality of ejection nozzles. Good. That is, if the ejection nozzles necessary for printing the image can be detected from the data to be printed, the flushing image and the check pattern may be formed by ejecting the ink only from the relevant ejection nozzles. Accordingly, in this case, the flushing image and the confirmation image such as the check pattern are printed without ejecting the ink from the ejection nozzles that are not necessary for printing the image.

In the above-described first and second embodiments, printing of the image on the sheet 2 is performed based on the flushing image when it is determined that all the discharge nozzles of the print head are not clogged. And a control unit that controls the print head to stop printing an image on the paper 2 when it is determined that a part of the discharge nozzle of the print head is clogged. Although the case has been described, the control unit is not necessarily provided. Therefore, when the control unit is not provided, after the state of the print head is detected based on the flushing image, based on the detected result, the printer is operated to start or stop printing. There is a need to do. In addition, even when the control unit is provided,
Only one of the print start and print stop may be controllable.

Further, in the above-mentioned first and second embodiments, the case where the print head and the reading head are provided so as to be close to each other has been described, but they are not necessarily provided so as to be close to each other. You don't have to.

In the first and second embodiments described above, the case where the surface of the printed paper is continuously read by the reading head has been described, but the surface of the printed paper is not necessarily continuous. It does not need to be read intermittently, and may be read intermittently at predetermined time intervals, for example.

Further, in the above-described first embodiment, the case where the flushing image is always printed before the printing of each image is described, but the printing of each image is not necessarily started. The flushing image does not necessarily have to be printed before printing, and the flushing image may be printed every time a predetermined number of images are printed.

In the above-described first and second embodiments, the case where a borderless image in which no margin is formed around the image area is printed is described as the print image, but the present invention is not limited to this. Alternatively, an edged image in which a margin is formed around the image area may be printed.

[0089]

As described above, according to the first aspect, the state of the printing unit such as whether or not there is an abnormality in the printing unit based on the confirmation image printed on the printing medium by the printing unit. Can be detected. Therefore, it is possible to prevent the processing capacity of the printer from being lowered in order to check the state of the printing unit. Furthermore, a separate device for checking the state of the printing unit is not required. As a result, it is possible to prevent the printer device from increasing in size and suppress an increase in manufacturing cost for the printer device.

According to the second aspect, after the confirmation image and the print image are continuously printed on the long print medium, the region other than the region corresponding to the print image (the region corresponding to the confirmation image is displayed. It is possible to prevent the print medium from being wasted because it can be cut and discarded.

According to the third aspect, the printing of the print image on the printing medium is started after it is confirmed that there is no abnormality in the printing unit. Therefore, the printing image is printed on the printing medium due to the abnormality of the printing unit. It is possible to suppress deterioration of the printed image. Therefore, due to the abnormality of the printing unit, the situation in which the printing has to be performed again hardly occurs.

According to the fourth aspect, when it is confirmed that there is an abnormality in the printing section, the printing of the print image on the printing medium is stopped, so that a misprint (printing in a state where the printing section has an abnormality) occurs. It is possible to prevent the print medium from being wasted.

According to the fifth aspect, during the flushing operation in the printing unit, the state of the printing unit is confirmed based on the confirmation image printed on the print medium by ejecting ink from all the ejection nozzles. As a result, misprinting due to an abnormality in the printing unit rarely occurs.

According to the sixth aspect, since the printing of the print image is started from the area close to the area of the print medium on which the confirmation image is printed, the printing between the confirmation image and the print image on the print medium is performed. The distance in the direction along the medium transport direction can be reduced. Therefore, it is possible to prevent the print medium and the ink from being wasted. When the printing unit can reciprocate in a direction perpendicular to the print medium conveyance direction, the reading unit can be downsized by moving the reading unit together with the printing unit. The configuration of the reading unit can be simplified and the manufacturing can be performed at low cost.

According to the seventh aspect, since it is confirmed that there is no abnormality in the printing section immediately before each of the plurality of print images is printed, the print image printed on the print medium due to the abnormality of the printing section is The deterioration can be suppressed more effectively. When an abnormality occurs in the printing unit, the print image of the print image on the print medium is printed before the printing of the next print image is started (when the print image being printed is finished when the abnormality occurs in the print unit). Since printing is stopped, it is possible to effectively prevent the print medium from being wasted due to misprinting.

According to the eighth aspect of the present invention, the printing unit continuously reciprocates in the direction perpendicular to the print medium conveyance direction and continuously prints the print image and the confirmation image along the direction perpendicular to the print medium conveyance direction. Therefore, the state of the printing section can be confirmed in real time based on the confirmation image. Therefore, when an abnormality occurs in the print unit, the printing of the print image on the print medium is immediately stopped even during the printing of the print image, so that the print medium is more effectively prevented from being wasted due to misprinting. Can be suppressed.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an inkjet printer according to a first embodiment.

FIG. 2 is a flowchart showing a procedure of a printing operation in the inkjet printer of FIG.

FIG. 3 is a diagram for explaining a printing operation in the inkjet printer of FIG.

FIG. 4 is a diagram showing a schematic configuration of an inkjet printer according to a second embodiment of the present invention.

5 is a flowchart showing a procedure of a printing operation in the inkjet printer of FIG.

FIG. 6 is a diagram for explaining a printing operation in the inkjet printer of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Inkjet printer 2 Paper (printing medium) 5 Inkjet printing unit 6 Image reading units 6a, 106a Reading head (reading part) 7,107 Cutting unit (cutting part) 8,108 Conveying roller unit (conveying means) 9 Crimping roller unit (Conveying means) 10, 110 Discharging roller unit (conveying means) 11 Print head (printing section) 15 Discharge nozzle 20 Controller 21 Clogging detection section (state detection section) 22 Control section (control section) 50-53, 150-155 Flushing image (confirmation image) 60-62, 160-162 image (print image)

Claims (8)

[Claims] 1. A transport unit for transporting a print medium, and a plurality of discharge nozzles for discharging ink onto the print medium transported by the transport unit, wherein the plurality of discharge nozzles discharge ink. A printing unit for printing a printing image based on the confirmation image and print data formed by the reading unit, a reading unit arranged downstream of the printing unit for reading the surface of the print medium, and the reading unit. An ink jet printer comprising: a state detection unit for detecting the state of the printing unit based on the read data corresponding to the confirmation image. 2. The print medium is an elongated member, and further comprises a cutting section arranged downstream of the reading section for cutting the print medium. 1. The inkjet printer according to 1. 3. A control unit for controlling the printing unit so that printing of a print image on a print medium is started when the state detection unit detects that the state of the printing unit is normal. The inkjet printer according to claim 1 or 2, further comprising: an inkjet printer. 4. The control unit, when the state detection unit detects that the state of the printing unit is abnormal,
The inkjet printer according to claim 3, wherein the printing unit is controlled so that the printing of the image on the printing medium is stopped. 5. The confirmation image is formed by ejecting ink from all of the plurality of ejection nozzles by a flushing operation in the printing section. Inkjet printer according to the item. 6. The reading unit is provided so as to be close to the printing unit.
The ink jet printer according to any one of 1. 7. The control means, when a plurality of print images are continuously printed on a print medium, always prints a confirmation image before the printing of each print image is started. The inkjet printer according to any one of claims 1 to 6, wherein the printing unit is controlled so as to control the printing unit. 8. The printing unit is capable of reciprocating in a direction perpendicular to a conveyance direction of a print medium, and the control unit is configured to print a confirmation image on the print medium and a conveyance direction of the print medium. The inkjet printer according to any one of claims 1 to 7, wherein the printing unit is controlled so that the printing units are printed at positions adjacent to each other in a direction perpendicular to the direction.