JP2002059565A - Method and apparatus for recording image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently specify malfunctioning nozzles. SOLUTION: Images are recorded by discharging ink by an ink jet head to a recording paper 17. A cut mark 41 or a sort mark is formed between images. The cut mark 41 is composed of a cleaning pattern 46 and a head state check pattern 47. In recording the cleaning pattern 46, ink is discharged at one time from each of nozzles to clean the nozzles. In recording the head state check pattern 47, nozzles are driven alternately to record pixels P of one nozzle array by two lines. A line sensor 45 of a check pattern read part measures a density of each pixel P of the head state check pattern 47. The nozzle which records the pixel, e.g. P3 not reaching a predetermined density is specified as the failing nozzle. The failing nozzle is separately cleaned.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording method and apparatus, and more particularly to an image recording method and apparatus capable of easily checking the state of each recording element.

[0002]

2. Description of the Related Art Printers that record images on recording paper include printers using an ink jet head and printers using a thermal head. In these printers, the printing element may malfunction for some reason. For example, in an ink jet printer, ink clogging occurs at a nozzle that discharges ink, and the ink discharge amount is reduced or ink is not discharged.
In this case, streaky color unevenness and density unevenness occur in the recorded image.

[0003]

Conventionally, when a recorded image is observed, if streak-like color unevenness or density unevenness occurs, the mode is switched to a head cleaning mode to perform cleaning and ink clogging. And abnormalities in the ejection direction are eliminated. In the cleaning process, the ink is vigorously ejected from each nozzle, the nozzle is sucked from outside to suck out the ink, and the periphery of the nozzle is wiped. As described above, in the case of manual operation, the detection of ink clogging is delayed, and an image may be recorded in a state where print quality is deteriorated.
In a home-use printer that enjoys printing personally, such a decrease in recording quality does not have much effect, but when used for business use, the delay in finding malfunctions of the recording element causes a large number of defective prints. Therefore, it is desired to reliably and easily find a malfunction of the printing element.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide an image recording method and apparatus capable of reliably and easily finding a malfunction of a recording element.

[0005]

In order to achieve the above object, in an image recording method according to the present invention, a recording paper or a recording head is formed by using a recording head having a plurality of recording elements arranged in a main scanning direction. In the method of recording an image on the recording paper by feeding in a sub-scanning direction, a head state check pattern for checking an operation state of the recording element is recorded outside a recording area of the image. It should be noted that the image recording method may be a serial print method as described in claim 2 in addition to the line print method. Here, the head state check pattern is a predetermined pattern formed outside the image area (non-image area) of the recording paper by the recording element, and based on this, it is possible to check the operation failure of each recording element. . In addition to the cut sheet type, a band-shaped recording paper is used as the recording paper. In this case, a head state check pattern is recorded at a boundary between a plurality of images.

It is preferable that the head state check pattern is recorded for each image boundary, for each order, for a fixed number of images, for a fixed time, or every time a recording paper roll is replaced. It is preferable that the head state check pattern is recorded at each image boundary and used as a cut mark, and cut off for each image based on the cut mark. Further, it is preferable that the head state check pattern is recorded for each order and used as a sort mark, and the unit is integrated for each order based on the sort mark. Preferably, the cut mark and the sort mark are identified by changing at least one of the width, length, position, color, and shape of the head state check pattern.

It is preferable that the recording head is an ink jet head, and that the ejection state of the nozzle of the ink jet head is inspected by the head state check pattern to identify a malfunction nozzle, and an alarm or head recovery operation is performed. This makes it possible to reliably detect nozzle clogging and abnormal ink ejection directions that are likely to occur in an ink jet printer. In addition, it is preferable to perform cleaning by ejecting ink from each nozzle before recording the head state check pattern. In this case, malfunctioning nozzles such as clogging can be reduced before inspection, and efficiency can be reduced. Good maintenance of the recording element can be performed. In addition, it is preferable to identify the cut mark and the sort mark by changing at least one of the width, length, position, color, and shape of the recording pattern by cleaning, so that these marks can be easily recorded. Can be.

In the image recording apparatus according to the present invention, a recording paper or a recording head is fed in a sub-scanning direction by using a recording head in which a plurality of recording elements are arranged in a main scanning direction, and an image is recorded on the recording paper. In the image recording apparatus, the recording element has recording data of a head state check pattern representing a recording state of a pixel corresponding to the recording element by driving the recording element,
A control unit for recording a head state check pattern outside the recording area of the image based on the recording data; According to a twelfth aspect of the present invention, in the image recording apparatus of the serial print system, a control unit for recording a head state check pattern outside an image recording area is provided. This makes it possible to easily inspect the operation failure of the recording element.

Preferably, the apparatus further comprises means for reading the head state check pattern, and means for specifying a malfunctioning recording element for identifying a malfunctioning printing element based on low density pixels in the read pattern. Is
A malfunctioning recording element can be automatically specified.
Further, it is preferable to include a unit for performing an alarm or a recovery operation for a malfunction when the malfunctioning recording element is identified by the malfunctioning recording element identification unit, thereby suppressing occurrence of a defective print. The recording head is an ink-jet head in which nozzles for discharging ink are arranged, and means for performing recovery measures for the operation failure is provided by discharging ink to the malfunctioning nozzle, sucking ink from outside, and forming a nozzle surface. At least one of the wipes
It is preferable that the head recovery operation be performed. Further, it is preferable that the ejection for cleaning the nozzle is performed immediately before recording the head state check pattern, and a cut mark or a sort mark is formed by a combination of the cleaning pattern by the ejection and the head state check pattern.

[0010]

FIG. 1 is a schematic view showing an ink jet printer according to the present invention. Inkjet printer 9
Is a paper feed unit 10, an image recording unit 11, a recording paper reservoir 1
2, a cutter unit 13 and a sorter 14.
The paper supply unit 10 includes a paper supply roller 16 in a recording paper magazine 15.
Is rotated to pull out the recording paper 17 from the magazine 15. The pulled out recording paper 17 is sent to the image recording unit 11. In this embodiment, the recording paper 17 has a width of 100 mm. The recording length of each image is about 150 mm, and the recording paper 17 is printed in a post card size. May be changed.

The image recording section 11 includes a paper feed roller pair 20, a platen roller 21, pressing rollers 22, 23, an ink jet head 24, and a drying device 25.
The paper feed roller pair 20 and the platen roller 21 are driven to rotate by a motor 19 via a driver 18. The pressing rollers 22 and 23 rotate in contact with the platen roller 21 and press the recording paper 17 against the platen roller 21. In the present embodiment, the recording paper 17 is attached to the platen roller 21.
The first and second pressing rollers 22 and 23 are arranged so that is wound in a range of 180 degrees.

The first and second pressing rollers 22, 2
3, the inkjet head 24 and the drying device 25
Are sequentially attached in the recording paper feed direction. The head 24 and the drying device 25 are arranged in parallel with the recording paper width direction (main scanning direction) orthogonal to the recording paper 17 feeding direction.

The ink jet head 24 is disposed at the top of the platen roller 21 near the recording paper outlet of the first pressing roller 22. As shown in FIG. 2, nozzles 30, 31, 32, and 33 for line recording of each color of yellow (Y), magenta (M), cyan (C), and black (K) are main-scanned in the inkjet head 24. Direction M
Are provided side by side. As is well known, a piezo element is arranged in the ink flow path near each of the nozzles 30 to 33 in the inkjet head 24. By contracting and expanding the ink flow path by this piezo element,
Discharge and supply of ink are performed.

Therefore, as shown in FIG. 1, the driving of each piezo element is controlled by an ink jet head driving unit 35. The inkjet head driving unit 35 supplies a driving signal according to image data to each piezo element. The controller 36 is connected to the inkjet head driving unit 35. The controller 36 has a frame memory 37
Is connected, and image data from an image reading device or an image output device is written in the frame memory 37.

The controller 36 obtains driving data of the piezo element for each nozzle 30 to 33 of each color based on the image data of each color. This drive data is sent to the inkjet head drive unit 35. Then, the controller 36
Each piezo element is driven via the head drive unit 35 in synchronization with the feeding of the recording paper 17. As a result, ink droplets of a size and quantity corresponding to the image data are ejected toward the recording paper 17, and the ink droplets adhere to the recording paper 17. Therefore, a full-color image is recorded on the recording paper 17 by Y, M, C, and K ink adhesion.

The memory 36a of the controller 36 stores mark creation data. Based on the mark creation data, the controller 36 forms a cut mark 41 and a sort mark 42 at the boundary of each image 40 as shown in FIG.

FIG. 4 is an enlarged plan view showing the cut mark 41 and a line sensor 45 for detecting the cut mark. The cut mark 41 includes a cleaning pattern 46 and a head state check pattern 47. The cleaning pattern 46 is formed by discharging a fixed amount of ink from each nozzle. Thereby, clogging of each nozzle is eliminated.

In this embodiment, a black solid pattern 46a formed by discharging black ink from the K nozzle 30; a yellow solid pattern 46b formed by discharging yellow ink from the Y nozzle 31; A magenta solid pattern 46c formed by discharging ink,
A cyan solid pattern 46d formed by ejecting cyan ink from the C nozzle 33 is formed side by side in the recording paper feed direction. In the present embodiment, each solid pattern 46a
Although the solid patterns 46a to 46d can be quickly dried by recording the solid patterns 46a to 46d side by side without overlapping, these solid patterns 46a to 46d may be recorded in an overlapping manner.

The head state check pattern 47 includes a plurality of line patterns 47a to 47h for each color. The line patterns 47a to 47h are arranged in the main scanning direction at a predetermined pitch so that pixels formed by ink ejection from each nozzle can be detected for each nozzle. Also, the line pattern 47 for this pitch is used.
a to 47h are arranged side by side in the sub-scanning direction. In the present embodiment, the pitch is set for two nozzles, whereby two line patterns are provided for each color. The pitch is for n nozzles (n is a natural number)
In this case, n line patterns are recorded.

As described above, since a gap is formed between the pixels P, the pixels P and the nozzles 30 to 33 that record the pixels P are formed.
Can be easily grasped. Further, as will be described later, when the head state check pattern 47 is read by the line sensor 45, even if the array density of the light receiving elements 45a is not as high as the density of the recording pixels P, a gap is formed between the pixels P in this manner. By recording such that the nozzles 30 to 33 are provided, the pixels P by the nozzles 30 to 33 can be easily and reliably associated with the line sensor 45.

As shown in FIG. 5, the sort mark 42 is substantially the same as the cut mark 41, and
6 and a head state check pattern 47. However, the cleaning pattern 46 is sorted by the sort mark 42 so that it can be identified from the cut mark 41.
Then, it is recorded twice consecutively. Thus, the length of the cleaning pattern 46 in the recording paper feed direction is different, so that the cut mark 41 or the sort mark 42 can be reliably specified.

By changing the number of recordings of the cleaning pattern 46, the cut mark 41 and the sort mark 4 are changed.
Alternatively, the cut mark 41 and the sort mark 42 may be identified by changing the length of each of the solid patterns 46a to 46d of the cleaning pattern 46 in the recording paper feeding direction instead of identifying the cut mark 41. For example, as shown in FIG.
By configuring each of the solid patterns 48a to 48d of the sort mark 48 to be twice as long as the length of each of the solid patterns 43a to 43d of the cut mark 41, both may be identified. Furthermore, the two may be identified by changing the arrangement order of each color of the cleaning pattern 46.

In the present embodiment, high-quality printing is realized by using both the dot diameter control method and the dot density control method as a gradation expression method. May be adopted. Note that each line is formed at a constant pitch in the sub-scanning direction S, and the piezo elements of each color are driven by shifting the image data to be recorded by that amount. As a result, eventually, ink droplets based on the same color image data are recorded on the same line.

As shown in FIG. 1, the drying device 25 moves the ink jet head 24 downstream from the mounting position of the ink jet head 24 about the center axis of the platen roller 21 in the recording paper feeding direction.
It is mounted at a position rotated 0 degrees. Since the drying device 25 is disposed in this manner, warm air from the drying device 25 does not flow out to the inkjet head 24,
Accurate recording is performed. In addition, a partition plate 38 as a shielding plate is disposed between the inkjet head 24 and the drying device 25. The partition plate 38 allows hot air from the drying device 25 to flow through the inkjet head 2.
The nozzles are not directed to the nozzle No. 4, the influence of the warm air can be further eliminated, and the recording accuracy can be improved.

As shown in FIG. 7, the drying device 25 is configured by attaching a heater 51 and a fan 52 to a frame 50. The frame 50 is formed in an elongated box shape, and the drying air outlet 50a is narrowed and formed in an elongated slit shape. The heaters 51 are wound in a coil shape and arranged in the sub-scanning direction S. Further, these heaters 51 are arranged side by side in the main scanning direction M at a constant pitch. As shown in FIG. 1, each heater 51 is controlled by a controller 36 via a heater driver 53.

The fan 52 is formed in a thin rectangular box shape.
For example, six are arranged in the main scanning direction M and attached to the upper portion of the frame 50. As shown in FIG.
Is provided with a motor 56 and a blower blade 57 provided in a fan case 55. The rotation of the motor 56 is controlled by the controller 36 via the driver 58 as shown in FIG. Therefore, the outlet 5 of the drying device 25
From 0a, warm air heated by each heater 51 blows out. The ink discharged on the recording paper 17 is dried quickly by the hot air.

FIG. 9 shows an example of the relationship between the unit drying area HA of one heater 51 on the recording paper 17 and the ink ejection area IPA of each nozzle. In the present embodiment, 100 ink ejection areas (unit ink ejection areas) IPA by one nozzle (main scanning direction) ×
A unit of 10 units (sub-scanning direction) collected in the unit drying area H
A.

FIG. 10 is a graph showing an example of the relationship between the total ink ejection amount in the unit drying area HA and the heat energy applied by the heater 51 to the unit drying area HA. In this embodiment, the heat energy applied by the heater 51 is set to increase as the total ink ejection amount in the unit drying area HA increases. This relationship is obtained in advance by experiments or the like. Then, the driving data of the heater 51 is obtained from the thermal energy to be applied to the unit drying area HA obtained from the relationship shown in FIG. In the present embodiment, the total ink ejection amount per unit drying area HA,
Drive data of heater 51 at this time (number of drive pulses)
Are obtained in advance, and these relationships are recorded in a look-up table memory (LUT) 39 in the controller 36. Then, the controller 36 calculates the total ink ejection amount for the unit drying area HA based on the image data, and calculates the heating data of each heater 51 of the drying device 25 from the total ink ejection amount. By driving each heater 51 by the heating data, the dried ink is reliably dried.

As described above, since drying is performed by each heater 51 in accordance with the amount of ink ejected in the unit drying area HA, drying is performed in accordance with the amount of ink ejected on the recording paper 17. For example, for a high density area where a large amount of ink of each color is ejected, the heating amount of the heater 51 corresponding to this area is increased, whereby the ink on the recording paper 17 is dried quickly and efficiently without waste. You. Therefore, a decrease in chroma and resolution due to mixing of the undried ink on the recording paper 17 can be suppressed. In addition, the ink does not dry and does not contact the pressing roller 23, so that the recording paper 17 is not stained with the ink.

Further, as shown in FIG.
6 is provided with a pulse generator 61 for detecting the feed amount of the recording paper 17. The pulse generator 61 contacts the recording paper 17 and generates a pulse number proportional to the feed amount of the recording paper 17. The controller 36 counts the number of pulses from the pulse generator 61 to determine the recording paper feed amount per unit time. Based on the feed amount, the controller 36 determines whether the inkjet head 24 or the drying device 25
Of the heater 51 is determined. Further, the driving data of each heater 51 is corrected according to the feeding speed of the recording paper 17. For example, as the recording paper 17 is fed faster, the amount of heating by each heater 51 is increased. In addition, recording paper 1
If the feed of 7 is slow, the amount of heating by each heater 51 is reduced. Further, when the feed speed of the recording paper 17 is close to "0", the heating amount is set to "0" so that the recording paper 17 is not unnecessarily heated. Note that the feed motor 1 is simply used without using the pulse generator 61.
9 may be constituted by a pulse motor, and the above various timings may be determined by counting the number of drive pulses of the pulse motor.

The recording paper reservoir 12 is composed of the platen roller 21 and the pressing roller 23 of the image recording section 11, a movable guide 65, and a pair of conveying rollers 66 on the cutter section 13 side. By providing a speed difference (including stopping one of them), the recording paper 17 hangs down between the pressing roller 23 and the conveying roller pair 66 and is temporarily stored.

The movable guide 65 is provided rotatably coaxially with the platen roller 21. This movable guide 65
Is a guide position in which the leading end of the recording paper 17 is guided to the cutter unit 13, and the leading end of the movable guide 65 is close to the entrance of the nip portion of the pair of conveying rollers 66 when the leading end of the recording paper 17 passes (indicated by a solid line). After the leading end of the recording paper 17 has passed, the recording paper 17 is set to a retracted position (indicated by a two-dot chain line) for temporarily storing the recording paper 17 in a loop. The recording paper 17 hangs down in the space where the movable guide 65 is retracted, so that the recording paper 17 is temporarily stored.

The cutter unit 13 includes first, second, and third pairs of transport rollers 66, 67, 68, a check pattern reading unit 70, and a cutter 71. Each of the transport roller pairs 66 to 68 is driven to rotate by a motor 72.
The motor 72 is connected to the controller 36 via a driver 73.
The rotation is controlled by. The cutter 71 is controlled by the controller 36 via the driver 74 and cuts the recording paper 17 at the boundary position of each image, and separates the recording paper 17 into prints 75 for each image.

The check pattern reading section 70 has a line sensor 45 as shown in FIG. The line sensor 45 has a large number of light receiving elements 45a arranged in the width direction of the recording paper 17 (main scanning direction M).
The image is read in synchronism with the feed of 7. This read signal is sent to the controller 36. In the controller 36, based on the read signal, as shown in FIG.
And identify them.

In the present embodiment, the cut mark 41 and the sort mark 42 are identified based on the difference in length depending on the number of recordings of the cleaning pattern 46. If the cleaning pattern 46 has a length of one time, it is determined to be the cut mark 41, and if the cleaning pattern 46 has a length of two times, it is determined to be the sort mark 42.

Further, the controller 36 controls each mark 4
The density of each pixel P is measured based on the read signals of the head state check patterns 47 of 1, 42, and if this density does not exceed a predetermined reference value, the nozzle that has recorded this pixel P is regarded as a malfunctioning nozzle. Identify. For example, in FIG.
Since the density of the third pixel P3 of the yellow odd-numbered line pattern is low, the third nozzle that has recorded this pixel P3 is determined to be a malfunctioning nozzle.

When a malfunctioning nozzle is detected, the ejection amount of the nozzle becomes smaller than the normal ink ejection amount when recording the cleaning pattern 46 at the time of recording the next cut mark 41 or sort mark 42. The nozzles are ejected in a large amount and more vigorously than usual to clean the nozzles. Also, when cleaning nozzles of other colors, cleaning is performed on malfunctioning nozzles, and the number of times of cleaning is increased. As a result, ink clogging can be effectively eliminated.

If a malfunctioning nozzle is detected and a malfunction is detected even after the nozzle is cleaned, an alarm is issued and an operator is notified of ink clogging. The operator has selected a separate cleaning mode for this alarm,
Clean the nozzle. In this cleaning mode, for example, the ink in the nozzles is vigorously ejected while the ink in the nozzles is heated by a heating element (not shown), and efficient cleaning is performed. In addition, instead of or in combination with such cleaning by ink ejection,
Cleaning may be performed by suctioning ink or wiping off ink adhering to the nozzles. The ink suction is performed by the head recovery processing unit 77. In the head recovery processing unit 77, the inkjet head 24 is displaced to the recovery processing position, a suction head is applied from outside the nozzle, and the nozzle is cleaned by sucking out ink by suction. In the wiping process of the attached ink, cleaning is performed by wiping the ink attached to the nozzles. If ink clogging is not eliminated by such various cleaning processes, replacement of the inkjet head or the like is performed.

The controller 36 controls the cut mark 41
In addition, the rotation of the motor 72 is controlled based on the detection signal of the sort mark 42, and each image boundary portion of the recording paper 17 is sent to the cutter 71 in order, and as shown in FIG. To cut twice. Thereby, the cut mark 41 and the sort mark 42 at the boundary are cut off, and a print 75 for each image 40 is obtained. The prints 75 are stacked on the tray 83 after cutting. Further, based on the detection signal of the sort mark 42, the controller 36 controls the sorter 14 to set a new tray 83 at the print drop position. Thereby, each print 75 is inserted into one tray 83 for each order, and is united for each order.

The sorter 14 is configured by arranging a number of trays 83 on a belt conveyor 84. Then, based on the detection signal of the sort mark 42, the belt conveyor 84 is rotated and driven by the mounting pitch of each tray 83, so that a new tray 83 is set at the print drop position.

Next, the operation of the present embodiment will be described. When a print key or the like is operated to input a print start instruction, as shown in FIG. 1, first, the paper feed roller 16, the paper feed roller pair 20, and the platen roller 21 rotate. Thereby, the recording paper 17 is sent out to the image recording unit 11. A leading edge sensor of the recording paper 17 is provided near the ink jet head 24. The controller 36 detects the leading edge of the recording paper based on the recording paper leading edge detection signal from the leading edge sensor and the recording paper feed amount from the pulse generator 61. Specify the recording area. Then, predetermined ink droplets are ejected onto the recording area by the nozzles 30 to 33 corresponding to the image data, and ink jet recording is performed.

When the recording paper 17 from which the ink has been discharged is sent to the drying device 25, the heating amount of each heater 41 is controlled in accordance with the amount of ink discharged to the unit drying area HA, and the heating corresponding to the amount of ink discharged is performed. Dried in quantity. Thereby, efficient drying is performed.

As shown in FIG. 3, a cut mark 41 is recorded on the boundary of each image 40 by the ink jet head 24. In addition, at the break of each order, a sort mark 42 also serving as a cut mark is recorded at the boundary of each image 40 by the inkjet head 24. As shown in FIGS. 4 and 5, when recording the cleaning pattern 46 of each of the marks 41 and 42, a certain amount of ink is ejected from each nozzle more intensely than usual to clean each nozzle. When recording the head state check pattern 47, for example, first, odd-numbered K nozzles are driven to record pixels P one by one, forming an odd-numbered line pattern 47a. Next, one line of recording paper 1
After the 7 is sent, the even-numbered K nozzles are driven to record the pixels P one by one again, forming the even-numbered line pattern 47b. Similarly, line patterns 47c to 47h are formed for each of the other colors Y, M, and C.

As shown in FIG. 1, in the cutter section 13, the marks 41 and 42 are detected by the line sensor 45 to specify the cut position. Further, the density of each pixel P of the head state check pattern 47 of each of the marks 41 and 42 is detected, and when the density of these pixels P does not exceed the reference value,
The nozzle on which the pixel P is recorded is determined to be malfunctioning. For the nozzles determined to be defective in operation, the ink ejection amount is made larger than that for the other normal nozzles at the time of recording the cleaning pattern of the next mark, and cleaning is performed. Further, the cleaning of the malfunctioning nozzle is performed not only for the general nozzle cleaning of the color, but also for the cleaning of the nozzles of other colors, so that the ink clogging is surely eliminated.

As shown in FIG. 3, based on the detection signal of the cut mark 41 or the sort mark 42, a boundary portion including these marks 41 and 42 is
It is cut at 0,81. At the start of recording, a cut mark 41 is recorded at the leading edge of the image 40, and the margin at the leading end of the recording paper is cut off based on this. When the sort mark 42 is detected, each image is cut off at this sort mark position in the same manner as the cut mark 41, and a sort signal indicating the break of each order is sent. When the recording of a series of images is completed and the next image is not recorded, the leading end of the recording paper 17 is
Is returned to the second pressing roller 23 to be in a print standby state.

In this embodiment, the width of the recording paper 17 is set to 100
mm, the recording length of one image including the cut mark is 150
mm, the feed speed (recording speed) of the recording paper 17 is 30 mm / sec.
The printing is performed with the recording width in one pass of the inkjet head 24 being 100 mm. However, the recording speed is reduced by applying to a full-color printer having a recording width of 80 mm or more and a recording speed of 20 mm / sec or more. And the ink can be dried quickly.

In the above embodiment, an area formed by arranging 100 unit ink ejection areas IPA by the nozzles 30 to 33 of the ink jet head 24 is defined as a unit drying area H.
However, these relationships are not limited to the above and may be changed as appropriate.

In the above embodiment, the unit drying area H
As shown in FIG. 10, the relationship between the total ink ejection amount in A and the heat energy applied by the heater 41 to the unit drying area HA is such that as the total ink ejection amount increases, the heat energy increases accordingly. . Further, when even a small amount of ink is ejected, the heater 41
Is heated. However, when the ink ejection amount is small, the air may be simply blown without heating the heater. For example, at the time of low ink ejection, the heater 41
May be set to “0” to reduce power consumption.

In the above embodiment, the heating amount of each heater 51 is controlled in accordance with the ink ejection amount for each unit drying area HA. However, the blowing amount of the fan 52 may be controlled instead or additionally. . Further, the heating may be simply performed uniformly without performing the heating or the adjustment of the blowing amount according to the ink discharge amount. Also, the unit drying area H according to the ink ejection amount
Although the heat energy applied to A is changed continuously, it may be changed stepwise. For example, two-stage or three-stage heating may be used. Alternatively, the total amount of ink discharged for each recording line may be obtained, and the amount of heating of the heater and the amount of air blown by the fan may be controlled in accordance with the total amount of ink discharged for each line. In the above embodiment, the heater 51 and the fan 52
Although the drying device 25 is used, the drying device may be configured by using compressed air instead of the fan 52.

Instead of using a drying device for blowing hot air onto the recording paper, a thermal head is provided upstream of the ink jet head in the recording paper feed direction, and the recording paper is preheated in accordance with the ink ejection amount. May be. Note that, instead of using the preheating amount according to the ink ejection amount, preheating may be simply applied uniformly. Further, instead of the drying device or the thermal head, a heater may be built in the platen roller to heat the recording paper and dry the ink.
Further, the ink may be naturally dried without using a preheating device or a drying device.

In the above embodiment, as shown in FIG.
In each of the inkjet heads 24, the Y, M, C, and K nozzles 30 to 33 are formed in a line shape. However, the present invention is not limited to this. The present invention may be carried out for those that have been. For example, as shown in FIG. 11, a K inkjet head 90 having a nozzle for black ink,
Two print stages 92 and 93 are formed by using the respective color inkjet heads 91 having M and C color nozzles, and the respective heads 9 of these print stages 92 and 93 are formed.
Drying devices 94 and 95 are provided for 0 and 91, respectively. The recording paper 17 between the print stages 92 and 93 and between the print stage 93 and the cutter unit 13 has a slack 1
7a is provided so that a slight feed fluctuation of the recording paper 17 in each of the print stages 92 and 93 is not transmitted to another print stage. In the following FIGS. 11 to 15, the same components as those in the embodiment shown in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

In the case of a normal full-color image,
The ejection amount of black ink is smaller than the ejection amount of each color ink. For this reason, the K inkjet head 90 is arranged upstream of the inkjet head 91 of each color in the recording paper feed direction. Ink can be ejected. Therefore, efficient drying can be performed.

As shown in FIG. 12, the ink jet head 100 for K, the ink jet head 101 for Y,
The print stages 105 to 10 are provided by providing the inkjet head 102 for C and the inkjet head 103 for C.
8, each of these print stages 105 to 108
Drying devices 110, 111, 112, 113 are provided on the downstream side of the heads 100 to 103 in the recording paper feed direction, respectively, and the drying devices 110 to 113 provide unit drying areas HA for the inkjet heads 100 to 103.
The recording paper 17 may be dried with warm air in accordance with the amount of ink ejected from the recording paper 17. As in the embodiment shown in FIG. 11, efficient drying is performed by arranging the K inkjet head 100 on the upstream side in the recording paper feed direction from the inkjet heads 101 to 103 of each color.

As shown in FIG. 3, the nozzles 30 to 3 for each color
3 may be formed by a plurality of lines in addition to being formed in one line. In this case, the nozzle density in the main scanning direction is reduced by an amount corresponding to the increase in the number of lines, thereby facilitating the manufacture. Further, instead of the nozzle having a length corresponding to the entire width of the recording paper 17, a plurality of inkjet heads having a short length in the width direction of the recording paper are used, and these are combined to form an ink jet head having a long width in the width direction of the recording paper. A head may be configured.

When an image is recorded on a plurality of print stages as described above, a registration mark is formed at the leading end outside the image in the first print stage so that the image recording position does not shift. With this, even if the edge of the image is unclear in some image scenes, the registration mark is detected in front of each color head, and recording of each color is started based on the registration mark, thereby reliably identifying each recording start position. can do. In particular, by first recording a registration mark with black ink on the black ink print stage, each mark can be reliably detected.
If there is no margin for recording the registration mark, the image recording start position may be specified using a cut mark, a sort mark, or the like instead of the registration mark.

In the above embodiment, the cut mark and the sort mark are identified by changing the number of times of recording and the recording width of the cleaning pattern 46. Instead, as shown in FIG. The cut mark and the sort mark may be identified by changing the shape or the recording position. FIG. 3A shows that the sort mark 130 is recorded over the entire width of the recording paper 17 and the cut mark 131 is recorded on the recording paper 1.
7 is recorded short in the width direction. Thus, by detecting the length of each of the marks 130 and 131 in the recording paper width direction, the sort mark 130 or the cut mark 131 is detected.
Can be identified. These marks 130, 13
Reference numeral 1 denotes a cleaning pattern 4 as in the above embodiment.
6 and the head state check pattern 47, the head state check pattern 47 alone. As described above, all nozzles corresponding to the width of the recording paper are checked for each order, and a part of the nozzles are checked in printing each image, so that useless ink ejection can be suppressed.

As shown in FIGS. 13B and 13C, about half of the nozzles are checked by the sort marks 132 and 133, and the remaining half of the nozzles are checked by the plurality of cut marks 134 to 141. Is also good. Also in this case, since the total number of checks of each nozzle is reduced, useless ink ejection can be reduced.

Instead of forming a cut mark or a sort mark using the head state check pattern, a head state check pattern may be recorded separately from the cut mark or the sort mark. FIG. 14 shows an example of this, in which a cut mark 145 consisting of a rectangular solid mark is recorded on one side of the recording paper 17 and a sort mark 146 of the same shape is recorded on the other side of the recording paper. Further, when a fixed number of images, for example, ten images are recorded, the head state check pattern 147 is recorded at the boundary between the images.
The cut mark 145 and the sort mark 146 may be identified by changing the shape or color instead of changing the recording position. For example, a cut mark is constituted by a circle, and a sort mark is constituted by a rectangle or a triangle, whereby both are identified. Also, instead of recording the head state check pattern after recording a predetermined number of images, when a print order is switched, when the recording paper is replaced, when printing is started for the first time on that day, a predetermined time, for example, 10 minutes, has elapsed. At a later time, the head state check pattern 47 may be recorded. Also, head state check pattern 4
Before the recording of No. 7, ink was ejected from each nozzle to form the cleaning pattern 46, but this cleaning pattern 46 may be omitted.

In the above embodiment, the head state check pattern 47 is recorded with each color as one unit. Instead, the head state check patterns 47a and 47b for K are recorded at the boundary of the first image. The head state check pattern 47 for Y is located at the boundary of the next image.
c and 47d, the head state check patterns 47e and 47f for M at the boundary of the next image, and the head state check pattern 47 for C at the boundary of the next image.
g, 47h, these may be decomposed and recorded.

In the above embodiment, by driving each nozzle at a predetermined interval, the interval between the pixels to be recorded is increased, so that it is possible to cope with the case where the array density of the number of light receiving elements is lower than the nozzle array density. However, when the arrangement density of the number of light receiving elements is the same as the arrangement density of the nozzles, or when scanning the sensor to read each pixel as described later, the nozzles are simultaneously driven and one line is used. A head state check pattern may be formed.

In the above embodiment, the head state check pattern 47 is read by the line sensor 45. In addition, as shown in FIG.
The head state check pattern 47 may be read by moving the head 20 in the main scanning direction M in parallel. In this case, the light receiving elements 120a are arranged in the sub-scanning direction S to form the line sensor 120, and the line sensor 120 is translated in the main scanning direction M by the scanning mechanism 121. A mark sensor 123 is provided separately, and the head state check pattern 47 is set at the check pattern reading position based on a mark detection signal from the mark sensor 123.
Position. Instead of using the line sensor 120, a reading sensor including one light receiving element may be sent in the main scanning direction M by a scanning mechanism to read each line pattern line by line. In this case, the recording paper is fed by one line after the reading, the next line pattern is read, and the above is repeated to read the head state check pattern.

In the above embodiment, the pixels P are associated with the nozzles on which the pixels P are recorded in a one-to-one relationship. However, the relationship is not limited to one-to-one. When the density is detected and the detected density does not reach the predetermined value, cleaning may be simultaneously performed on the plurality of nozzles.

In the above-described embodiment, the present invention is applied to a line printer that records one line at a time in the width direction of the recording paper 17. In addition, as shown in FIG. Printer 1 that scans in the width direction of recording paper 162 to perform recording
The present invention may be implemented in 63. Reference numeral 164 denotes a guide rod that guides the head carriage 161 in the width direction of the recording paper 162, and reference numeral 165 denotes a platen member that supports the recording paper 162.

When recording the head state check pattern in the serial printer 163, each nozzle is sequentially driven while moving the head carriage 161 in the main scanning direction, and each pixel is obliquely printed with respect to the recording paper 162. Record.

FIG. 17 shows an example of a head state check pattern in the serial printer 163.
The (A) head state check pattern 170 indicates that the recording paper 162 is fed one pixel at a time in the sub-scanning direction, and that the inkjet head 16 is moved by the head carriage 161.
0 is moved in the main scanning direction, and each nozzle is sequentially driven in conjunction with this movement. The head state check pattern 170 includes pixels P that are separated in the width direction of the recording paper 162.

The head state check pattern 171 shown in FIG. 17B is obtained by moving the ink jet head 160 in the main scanning direction by the head carriage 161 without sending the recording paper 162, and interlocking this movement with each nozzle. It is obtained by driving. The head state check pattern 171 is composed of pixels P which are arranged in a direction obliquely intersecting the width direction of the recording paper 162 and are scattered.

FIG. 17C shows an example of a head state check pattern 172 employed when the number of nozzles is large. In this embodiment, a head state check pattern composed of a plurality of oblique lines is formed by dividing each nozzle by a plurality of numbers in the sub-scanning direction and sequentially driving each nozzle of each of the divided groups.

Also in the above serial printer, the cut mark and the sort mark may be formed by changing the number of times of the head state check pattern and the cleaning pattern, the recording position, the recording order of each color, and the like.

In the above-described embodiment, ink clogging in each nozzle of the ink jet head and malfunctions of the drive elements and drive circuits of the nozzles are detected. A defect may be detected. For example, when checking for a malfunction of the printing element of the thermal head, the malfunction is corrected by correcting the heating drive data of the malfunctioning printing element. The present invention is not limited to a thermal printer, and the present invention may be applied to a printer that exposes an instant film with a light emitting element head in which a large number of light emitting elements are arranged.

In the above embodiment, the ink jet heads 24, 90, 91, 100 to 103 having piezo elements are used.
However, various mechanisms may be applied as a mechanism for ejecting ink. For example, a flow control valve system comprising a piezo element and a diaphragm, a thermal ink jet system in which a heating element is used to heat ink liquid to generate bubbles and eject ink, and an ink droplet is formed by using an electrode. A continuous ink jet system that applies electric charge, collects unnecessary droplets with a deflection electrode on a baffle plate, and discharges necessary ink droplets on recording paper, applies a high voltage according to image signals, and uses this high voltage Various ink jet systems such as an electrostatic suction ink jet system in which ink droplets are sucked onto recording paper and an ultrasonic ink jet system in which ink droplets are generated by vibrating an ink liquid using ultrasonic waves may be used. Also,
As the ink to be used, other color inks such as light magenta and light cyan may be used in addition to Y, M, C, and K.

Although the roll type recording paper is used in the above embodiment, a cut sheet type recording paper may be used instead. In this case, the head state check pattern is recorded outside the image recording area. If necessary, a sort mark may be recorded in addition to the head state check pattern.

[0072]

According to the present invention, since the head state check pattern for checking the operation state of the recording element is recorded outside the recording area of the image, it is possible to easily detect a malfunction of the recording element. it can. In particular, by recording the head state check pattern at each image boundary, at each order, at a certain number of images, at a certain time, or at every time the recording paper roll is replaced, an operation suitable for each recording device is performed. A defect inspection period can be set.

Further, the head state check pattern is recorded at each image boundary and used as a cut mark, and is separated for each image based on the cut mark.
Using the cut mark, the head state can be inspected each time one image is recorded. Therefore, the head state can be checked every time an image is recorded, and the number of defective prints can be reduced. In addition, a head state check pattern is recorded for each order and used as a sort mark, and the head state is inspected by using the sort mark by using the sort mark as a reference to make one unit for each order. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an ink jet printer of the present invention.

FIG. 2 is an enlarged front view showing the ink jet head.

FIG. 3 is a plan view showing an example of a boundary portion of an image.

FIG. 4 is a plan view showing a cut mark and a line sensor.

FIG. 5 is a plan view showing a sort mark.

FIG. 6 is a plan view showing a sort mark according to another embodiment.

FIG. 7 is an exploded perspective view showing the drying device.

FIG. 8 is a longitudinal sectional view of a drying device.

FIG. 9 is a plan view illustrating an example of a relationship between a unit ink ejection area and a unit drying area.

FIG. 10 shows the total ink ejection amount per unit drying area,
It is a graph which shows an example of the relationship with the applied heat energy to a unit drying area.

FIG. 11 is a schematic view showing another embodiment using two sets of ink jet heads and a drying device.

FIG. 12 is a schematic view showing another embodiment using four sets of inkjet heads and a drying device.

FIG. 13 is a plan view illustrating an example of a sort mark and a cut-mark in another embodiment.

FIG. 14 is a plan view showing a sort mark, a cut mark, and a head state check pattern according to another embodiment.

FIG. 15 is a schematic diagram illustrating a check pattern reading unit according to another embodiment.

FIG. 16 is a schematic view showing a main part of the serial printer.

FIG. 17 is a plan view illustrating an example of a head state check pattern in a serial printer.

[Explanation of symbols]

Reference Signs List 9 inkjet printer 10 paper feed unit 11 image recording unit 12 recording paper reservoir 13 cutter unit 14 sorter 17 recording paper 20, 66 to 68 transport roller pair 21 platen roller 24, 90, 91, 100 to 103 inkjet head 25, 94, 95 , 110-113 Drying device 40 Image 41, 131, 134-141, 145 Cut mark 42, 48, 130, 132, 133, 146 Sort mark 45 Line sensor 46 Cleaning pattern 47, 147, 170-172 Head state check pattern 51 Heater 70,122 Check pattern reading unit P pixel

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Eiichi Kito 798, Miyadai, Kaisei-cho, Ashigara-gun, Kanagawa Photo Film Co., Ltd. (72) Inventor Yasuyuki Hosono 798, Miyadai, Kaisei-cho, Ashigara-gun, Kanagawa F-term (reference) in Film Co., Ltd. 2C056 EA14 EB27 EB40 EB42 EC26 EC54 FA10 HA58

Claims (16)

[Claims] 1. A method of recording an image on a recording sheet by feeding a recording sheet or a recording head in a sub-scanning direction by using a recording head in which a plurality of recording elements are arranged in a main scanning direction. An image recording method, further comprising recording a head state check pattern for checking an operation state of the recording element. 2. A recording head comprising a plurality of recording elements arranged in a sub-scanning direction is moved in a main scanning direction by a head carriage to perform band-like recording on recording paper, and the recording paper is synchronized with the band-like recording. Alternatively, in a method of recording an image on the recording paper by feeding a recording head and a head carriage by an amount corresponding to the band-shaped recording in the sub-scanning direction, checking an operation state of the recording element outside a recording area of the image. Recording method for recording a head state check pattern for recording. 3. The recording sheet according to claim 1, wherein a plurality of images are recorded on the recording sheet, and the head state check pattern is recorded on a boundary between the plurality of images. Or the image recording method according to 2. 4. The head state check pattern is recorded for each image boundary, for each order, for a fixed number of images, for a fixed time, or every time a recording paper roll is replaced. Item 4. The image recording method according to any one of Items 1 to 3. 5. The image recording method according to claim 3, wherein the head state check pattern is recorded at each image boundary and used as a cut mark, and is separated for each image based on the cut mark. 6. The head status check pattern is recorded for each order and used as a sort mark, and a unit is formed for each order based on the sort mark. Image recording method. 7. The width of the head state check pattern,
7. The image recording method according to claim 6, wherein the cut mark and the sort mark are identified by changing at least one of a length, a position, a color, and a shape. 8. The recording head is an ink-jet head, wherein an ink ejection state of a nozzle of the ink-jet head is inspected by the head state check pattern to identify a malfunction nozzle, and an alarm or a head recovery operation is performed. 8. The image recording method according to claim 6, wherein: 9. The image recording method according to claim 8, wherein ink is ejected from each nozzle to perform cleaning before recording the head state check pattern. 10. The image recording apparatus according to claim 9, wherein the cut mark and the sort mark are identified by changing at least one of a width, a length, a position, a color, and a shape of the recording pattern by the cleaning. Method. 11. An image recording apparatus which uses a recording head in which a plurality of recording elements are arranged in a main scanning direction and feeds recording paper or a recording head in a sub-scanning direction to record an image on the recording paper. And a control unit for recording the head state check pattern outside the recording area of the image based on the recording data based on the recording data. An image recording apparatus, comprising: 12. A recording head in which a plurality of recording elements are arranged in a sub-scanning direction is moved in a main scanning direction by a head carriage to perform band-shaped recording on recording paper, and the recording paper is synchronized with the band-shaped recording. Alternatively, in an image recording apparatus for recording an image on the recording paper by feeding a recording head and a head carriage by an amount corresponding to the band-shaped recording in the sub-scanning direction, recording the pixels corresponding to the recording element by driving the recording element. An image recording apparatus, comprising: a control unit that has recording data of a head state check pattern indicating a state, and records a head state check pattern outside a recording area of the image based on the recording data. 13. The printing apparatus according to claim 1, further comprising: means for reading the head state check pattern; and means for specifying a malfunctioning recording element based on low density pixels in the read pattern. Item 13. The image recording device according to Item 11 or 12. 14. The image recording apparatus according to claim 13, further comprising means for performing an alarm or a recovery operation of the malfunction when the malfunction recording element is identified by the malfunction recording element identification means. apparatus. 15. The recording head is an ink jet head in which nozzles for ejecting ink are arranged, and the means for performing the operation for recovering the operation failure discharges ink to the nozzle having the operation failure and supplies the ink from the outside. 15. The image recording apparatus according to claim 14, wherein at least one head recovery operation of suction and wiping of a nozzle surface is performed. 16. An ejection operation of the head recovery operation is performed immediately before recording of the head state check pattern, and a cut mark or a sort mark is formed by a combination of the cleaning pattern by the ejection and the head state check pattern. The image recording apparatus according to claim 15, wherein