JP2004009531A - Image recording apparatus and its control process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To decrease an effect of a non-output port and to alleviate thereby deterioration of quality of printing even when the non-output port exists and the position is not accurately determined. <P>SOLUTION: When a block (constituted of a plurality of output ports) at least containing the non-output port is determined, according to the existing ratio of dots and continuity of the dots of image data to be recorded by the block (S13-S16), it is determined whether the block of interest is driven by a usual heat pulsing (S17) or by a complemental heat pulsing (S18). <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image recording apparatus that records an image by discharging an ink liquid onto a recording medium such as recording paper, a control method thereof, and a storage medium.
[0002]
[Prior art]
In general, an ink jet recording apparatus performs recording by ejecting ink from a recording head to a recording medium (recording paper or the like), and it is easy to make the recording head compact and record a high-definition image at high speed. It has the advantages of low running cost and low noise due to the non-impact method. Another advantage is that it is structurally easy to record a color image using multicolor inks. Above all, a full-line type apparatus using a line-type recording head in which a large number of ejection ports are arranged in the paper width direction can further increase the recording speed.
[0003]
In the case of the full line type, printing is performed in one pass. Therefore, there is no alternative nozzle when the nozzle becomes non-discharged due to the fixation of the ink or the failure of the ink discharge means (heater, piezoelectric element, etc.). In such a case, the pixel at the position corresponding to the non-ejection nozzle is not printed, and the print quality is greatly reduced.
[0004]
Therefore, in order to improve the lack of the image, it is conceivable to replace the recording head every time the non-ejection of several nozzles occurs, but this greatly increases the running cost.
[0005]
To cope with this problem, in a full-line type color inkjet recording apparatus having a plurality of recording heads (cyan, magenta, yellow, and black), when a non-ejection nozzle is detected, the ejection is performed to the same pixel as the non-ejection nozzle. There is a method of supplementing by substituting another print head that can be used.
[0006]
[Problems to be solved by the invention]
However, in the case of the above-described conventional ink jet recording apparatus, since a recording head of a different color from the non-ejection nozzle is used instead, the influence on print quality is great. In particular, it becomes remarkable in the case of printing by a substitute head for a non-ejection nozzle of a yellow or cyan print head. Furthermore, when a plurality of non-ejection nozzles are adjacent to each other, there is a problem that the color of the substitute print head is easily recognized.
[0007]
In addition, since it is necessary to complement a specific non-ejection nozzle on a nozzle-by-nozzle basis, high accuracy is required to detect the non-ejection nozzle. Therefore, an image reading unit such as a scanner is required, and the recording medium is read by the image reading unit to detect a pixel that has not been ejected. In this case, a reading accuracy higher than the recording density of the ink jet recording apparatus is required.
[0008]
The present invention has been made in view of such a problem, and even if there is a non-ejection port and it is not possible to set the exact position, the influence of the non-ejection port is reduced, thereby reducing the deterioration of print quality. It is an object of the present invention to provide an image recording apparatus, a control method thereof, and a storage medium which make it possible to perform such operations.
[0009]
[Means for Solving the Problems]
In order to solve this problem, for example, an image recording apparatus of the present invention has the following configuration. That is,
An image recording apparatus that discharges ink liquid from a plurality of ink liquid discharge ports provided in a recording head and that can control the amount of discharged ink,
Identifying means for identifying an area position by a plurality of continuous ink ejection ports, including a position of a non-ejection port where ink liquid cannot be normally ejected,
Control means for controlling a discharge ink liquid amount of the ink droplet discharge port group in the area based on a state of image data to be recorded by the ink droplet discharge port group included in the specified area.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0011]
FIG. 1 and FIG. 2 are internal structural views of an ink jet recording apparatus according to the present invention. A recording apparatus 1 having an automatic paper feeder includes a paper feed unit 2, a paper feed unit 3, a paper discharge unit 4, and a print head unit 7. Therefore, these are divided into items and outlines are sequentially described. FIG. 1 is a cross-sectional view showing the overall configuration of the recording apparatus 1, and FIG. 2 is a cross-sectional view of the configuration of a paper feeding unit 3 of the recording apparatus 1. FIGS. A description will be given of the paper feed unit, (III) recording head unit, and (IV) paper discharge unit.
[0012]
(I) Paper feed unit
The paper feed unit 2 is detachable in the form of a cassette along the direction of arrow c shown in the figure, and a pressure plate 21 for loading the recording paper P and a feed rotating body 22 for feeding the recording paper P are attached to the base 20. It is configured to be attached. The pressure plate 21 is rotatable about a rotation axis a coupled to the base 20, and is urged by a pressure plate spring 24 to the feeding rotating body 22. A separation pad 25 made of a material having a large coefficient of friction, such as artificial skin, for preventing double feeding of the recording paper P is provided at a portion of the pressure plate 21 facing the feeding rotating body 22. Further, the base 20 covers a corner in one direction of the recording paper P, a separation claw 26 for separating the recording paper P one by one, and a release mechanism for releasing the contact between the pressure plate 21 and the rotary feeder 22 (not shown). Release cam is provided.
[0013]
In the above configuration, in the standby state, the release cam pushes the pressure plate 21 down to a predetermined position. Thereby, the contact between the pressure plate 21 and the feeding rotating body 22 is released. In this state, when the driving force of the transport roller 32 is transmitted to the feed rotator 22 and the release cam by a gear or the like, the release cam separates from the pressure plate 21 and the pressure plate 21 rises, and the feed rotator 22 The recording paper P is picked up by the rotation of the feeding rotating body 22 and starts to be fed, and is separated by the separation claw 26 one by one and sent to the paper feeding unit 3. The feed rotator 22 rotates until the recording paper P is fed into the paper feed unit 3, and is again in a standby state in which the contact between the recording paper P and the feed rotator 22 is released, and the driving force from the transport roller 32 is reduced. Cut off.
[0014]
Reference numeral 90 denotes a feeding rotating body for manual sheet feeding. The recording paper P set on the manual feed tray 91 is fed by a feed rotating body 90 in accordance with a recording command signal of a computer, and is transported to a transport roller 32.
[0015]
(II) Paper sending unit
The paper feed unit 3 has a transport belt 31 that adsorbs and transports the recording paper P, and a PE sensor (not shown). The transport belt 31 is driven by a drive roller 34 and is wound around a transport roller 32 and a pressure roller 35 which are driven rollers.
[0016]
A pinch roller 33 driven by the conveyor belt 31 is provided at a position opposing the conveyor roller 32. The pinch roller 33 is pressed against the conveyor belt 31 by a spring (not shown) to guide the recording paper P to a recording unit. Further, an upper guide 27 and a lower guide 28 for guiding the recording paper P are provided at an entrance of the paper feeding unit 3 to which the recording paper P is conveyed. Further, the upper guide 27 is provided with a PE sensor lever 29 for transmitting the detection of the leading and trailing edges of the recording paper P to a PE sensor (not shown). Further, a recording head 7 that forms an image based on image information is provided downstream of the transport roller 32 in the recording paper transport direction.
[0017]
In the above configuration, the recording paper P sent to the paper feeding unit 3 is guided by the upper guide 27 and the lower guide 28 and sent to a pair of rollers including a transport roller 32 and a pinch roller 33. At this time, the leading end of the recording paper P conveyed by the PE sensor lever 29 is detected, and the printing position of the recording paper P is obtained by this. The recording paper P is transported by the rotation of the transport belt 31 via the transport rollers 32 by an ultrasonic motor described later.
[0018]
(III) Recording head
As the recording head 7 of the first embodiment, a line type ink jet recording head in which a plurality of nozzles (for one line) are arranged in a direction orthogonal to the transport direction of the recording paper P is used. The recording heads 7 are arranged at predetermined intervals in the order of 7K (black), 7C (cyan), 7M (magenta), and 7Y (yellow) from the side, and the recording head 7 is attached to a head holder 7A. The recording head 7 can apply heat to the ink by a heater or the like. Then, the ink causes film boiling due to the heat, and ink is ejected from the nozzles 70 of the recording head 7 by a pressure change caused by growth or contraction of bubbles due to the film boiling, and an image is formed on the recording paper P.
[0019]
One end of the recording head 7 is rotatably fixed by a shaft 71, the protruding portion 7 </ b> A formed at the other end is engaged with the rail 72, and the distance (paper interval) between the nozzle surface and the recording paper P is defined. It is supposed to be.
[0020]
(IV) Paper discharge unit
The paper discharge unit 4 includes a paper discharge roller 41 and a spur 42. The recording paper P, on which an image has been formed by the recording unit, is sandwiched between the paper discharge roller 41 and the spur 42, conveyed, and transferred to the paper discharge tray 43. Is discharged.
[0021]
<Description of operation>
Next, the configuration and operation of suction conveyance in the recording unit will be described with reference to FIGS.
[0022]
Reference numeral 31 denotes a conveyor belt that moves while adsorbing and holding the recording paper P, and is made of a synthetic resin such as polyethylene or polycarbonate having a thickness of about 0.1 mm to 0.2 mm, and has an endless belt shape. I have. Numeral 36 denotes an attraction force generating means, which is fixed at a position opposing the recording head 7 and generates an attraction force on the transport belt 31 at the recording portion of the recording head 7 by applying a voltage of about 0.5 kV to 10 kV. And is connected to a high-voltage power supply (not shown) that generates a predetermined high voltage.
[0023]
As described above, 32, 34, and 35 are rollers that support the transport belt 31 and apply an appropriate tension, and 34 is connected to the paper feed motor 50. Further, a paper pressing member 39 as pressing means for pressing the recording paper P against the conveying belt is attached around the rotation axis of the pinch roller 33 as a rotation center, and is urged toward the conveying belt 31 by urging means (not shown). The paper pressing member 39 is made of a conductive metal plate.
[0024]
Reference numeral 38 denotes a cleaning roller pair, which is provided to be pressed between the belts 31. The cleaning roller pair 38 is capable of absorbing ink to remove dirt such as ink attached to the belt 31, and has a pore diameter for preventing deterioration in durability. Of small cells (preferably 10 μm to 30 μm).
[0025]
Next, the operation will be described.
[0026]
The recording paper P is nipped between the pinch roller 33 and the transport belt 31, guided to the recording unit, enters the suction force generating unit while being pressed against the transport belt 31 by the paper pressing member 39, and the suction force generating unit 36. Is attracted to the flat portion of the transport belt 31 by the attraction force given by the printer, and is fed in the direction of arrow a by the paper feed motor 50 and the rollers 34 while being printed by the recording head. At this time, the conveying belt 31 holding the recording paper P has no members traveling to the recording head 7 side even when recording the leading and trailing ends of the recording paper P. Can be recorded while approaching, and a highly accurate recorded image can be obtained.
[0027]
Further, when a large amount of ink is ejected onto the recording paper P, the recording paper P swells and causes wavy (cockling). In this case as well, the recording paper P is attracted to the conveyor belt 31 by the suction force of the suction force generating means 36 and the pressing force of the paper pressing member 39, so that the recording paper P does not float to the head 7 side, so that the head 7 And recording paper P does not come into contact with each other, and stable recording can be performed. Further, even when the end of the recording paper P is wavy or curled due to a change in environment such as temperature and humidity, the recording paper P is pressed against the transport belt 31 by the paper pressing member 39, and Since the sheet can be conveyed to the suction force generating section with the curl removed, stable suction can be performed in the recording section.
[0028]
<Description of control system>
FIG. 3 is a block diagram illustrating a configuration of a control unit of the inkjet recording apparatus according to the present invention and devices controlled by the control unit.
[0029]
7K is a recording head for black, 7C is a recording head for cyan, 7M is a recording head for magenta, and 7Y is a recording head for yellow. 100 is a solenoid for controlling the cleaning roller. 50 is a motor for controlling a driving roller for driving the transport belt. Reference numeral 102 denotes a sensor for detecting a reference position of the transport belt. A sensor 103 for detecting the sheet edge of the recording sheet is connected to the PE sensor lever 29.
[0030]
Although not shown in FIGS. 1 and 2, the transport belt position detecting sensor 102 is provided on the back side of the transport belt between the transport roller 32 and the pressure roller 35.
[0031]
80 is a control unit. 80a is a CPU, 80b is a ROM for storing programs, 80c is a work RAM used as a control, bitmap image development or reception buffer, and 80d is a gate array, each connected via a system bus. The gate array 80d includes a control signal for a drive roller motor and a feed rotator motor, a control signal for a cleaning roller solenoid, an image signal to a recording head, a recording head control signal, a conveyance belt dirt detection sensor, and a PE. Reads information from sensors, etc. 80e is an interface for receiving print data from the host computer and outputting status to the host computer, and 80f is an operation provided with a simple display device (liquid crystal display) and some buttons (switches). It is a panel.
[0032]
<Description of non-ejection recovery process>
FIG. 4 shows a configuration of a test print result for visually specifying an area including a non-ejection nozzle in the configuration of the inkjet recording apparatus according to the present invention. As shown in the figure, the test print includes a nozzle check pattern 104a adjusted so that a non-ejection nozzle can be visually recognized and an identification number (ID) 104b of an area arranged along the nozzle check pattern. Is done. This is repeatedly printed for each recording head included in the ink jet recording apparatus, and the ejection status of all the recording heads can be confirmed. Since it is difficult to assign an identification number to each nozzle, a certain number of areas (blocks) are defined, and IDs are assigned to the areas (blocks). Although four band-shaped patterns are recorded in the drawing, each band-shaped pattern is a result of recording by each recording head alone.
[0033]
This test printing is started by giving an instruction by a predetermined operation from an operation panel 80f provided in the ink jet recording apparatus. Further, data such as a nozzle check pattern recorded in test printing is read from the ROM 80b.
[0034]
FIG. 5 shows the relationship between the area specified in the test printing, the non-ejection nozzle, and the control block of the print head.
[0035]
As shown in the figure, the ejection sections of the print heads 105a to 105d are divided into a plurality of control blocks, and each block is assigned a block number B1, B2,..., Bn from the left end. In the case of the recording head used in the present embodiment, each block has 256 nozzles, and 28 blocks are arranged.
[0036]
The positional relationship with the recording paper 105e on which the test printing is performed is the same as that shown in FIG. 4, and the block numbers of the recording heads 105a to 105d correspond to the area IDs printed on the recording paper.
[0037]
In the figure, the non-ejection portion 105f can be confirmed in the nozzle check pattern ejected by the recording head 105a on the test-printed recording paper, and the non-ejection portion is in the vicinity of the area ID marked "B4". Can be identified. Therefore, it can be understood that the non-ejection nozzle generated in the recording head 105a (which head can be easily identified by the recording color) is any nozzle in the block B4.
[0038]
FIG. 6 illustrates the arrangement of nozzles and print information in a specific block of the print head (lines 106a to 106d). In the figure, hatched dots indicate ejection, and white dots indicate non-ejection. A method for determining whether or not the non-ejection nozzle needs to be complemented in the present embodiment will be described with reference to the drawings.
[0039]
First, an area ID including a non-discharge nozzle is specified by the above-described test printing, and this information (print head and its ID) is registered in the inkjet printing apparatus via the operation panel 80f. The scan of the print information (raster data) discharged from the block of the print head corresponding to the registered area ID is performed. At this time, it is determined whether complementation is necessary by evaluating the content of the recording information corresponding to the nozzle. In the present embodiment, the determination is made based on the density (duty) per area and the arrangement of the recording information (pattern continuity). Note that in order to be able to retain this registration information even when the power is turned on next time, the RAM 80c (or a part thereof) in the embodiment is supplied with backup power, and the apparatus is turned off. Although such information is not lost even if it is stored, it is understood that other means, for example, information stored in a non-volatile memory (for example, EEPROM or the like) may be used. Therefore, it is not limited to this.
[0040]
In the case of the raster data 106a, the duty is 0% and the pattern is "discontinuous" because all 256 nozzles are not ejected. Since the raster data 106b discharges all 256 nozzles, the duty is 100% and the pattern is “continuous”. The raster data 106c is "quasi-continuous" because the duty is 50% and the pattern is partially continuous. The duty of the raster data 106d is 14%, and the pattern is “discontinuous”. The determination procedure will be described later with reference to a flowchart shown in FIG.
[0041]
FIG. 7 illustrates a heat pulse used for control of discharging ink from the recording head. When the waveform of the heat pulse 107a is used, the ink is ejected with a small ejection amount, so that the ink is used in normal printing. When the waveform of the heat pulse 107b is used, ink is ejected with a larger ejection amount than usual, and this is used for printing when complementing a non-ejection nozzle. In this way, large and small dots can be distinguished by selectively using two types of ejection amounts.
[0042]
FIG. 8 is an enlarged view showing a state where the ejected ink lands on the recording paper.
[0043]
In the present embodiment, since a recording head having a resolution of 600 dpi is used, the pixel size per dot is 42.3 μm × 42.3 μm. The ejection amount during normal printing is 14 pl, and the dot size upon landing is φ60 μm. When there is no non-discharge nozzle, dots are arranged as shown in landing example 108a.
[0044]
However, when a non-discharge nozzle is generated, a large blank space is formed between dots as in the landing example 108b. This results in white streaks and missing pixels, leading to a reduction in recording quality. At this time, by increasing the ink ejection amount to 17 pl using the heat pulse 107b of FIG. 7, the dot size at the time of landing can be increased to φ65 μm. As a result, blank spaces generated between dots can be reduced as compared with normal ejection, so that white streaks and pixel omissions can be suppressed, and deterioration in recording quality can be reduced.
[0045]
9 to 11 are flowcharts for controlling the ink jet recording apparatus according to the present invention. Hereinafter, the control method of each process will be described with reference to flowcharts.
[0046]
The non-ejection area detection processing shown in the flowchart of FIG. 9 is a control procedure for specifying an area including the non-ejection nozzle when the non-ejection nozzle is generated. Is started in response to the test print start instruction. The test printing start instruction and subsequent operations are performed using input means (buttons or a touch panel) of an operation panel 80f provided in the inkjet recording apparatus.
[0047]
First, a nozzle check pattern recorded in the ROM 80b is read (step S1). Then, the area ID corresponding to the control block position of the print head is marked in line with the read nozzle check pattern (step S2). The test print pattern thus created is repeatedly recorded for every head mounted on the recording paper (step S3). As a result, an equivalent of the test print result shown in FIG. 4 is obtained, and the operator visually evaluates the print state. If the non-ejection is confirmed, the color of the corresponding portion and the area ID marked on the upper part are confirmed, and the print head in which the non-ejection nozzle has occurred and its area are specified. This operation is also performed using the operation panel 80f. If the registration operation is not performed and the user is brought online, the registration processing is skipped.
[0048]
The non-ejection area registration processing shown in the flowchart of FIG. 10 is a control procedure for registering the ID of the area including the non-ejection nozzle, identified by the non-ejection area detection processing of FIG. After the non-ejection area detection processing in FIG. Note that the registration instruction and subsequent operations are performed using input means (buttons or touch panels) of an operation panel provided in the inkjet recording apparatus.
[0049]
First, the color of the print head in which the non-ejection nozzle has occurred is selected (step S4). Then, the area ID acquired in the non-ejection area detection processing of FIG. 9 is input (step S5). Subsequently, if there is another area ID of the same recording head, the process returns to step S5 to input the area ID, and inputs all the acquired area IDs (step S6). The input area ID is stored in the memory 80c (Step S7). Further, if the area IDs of the other recording heads have been acquired, the processing from step S4 is repeated to register the area IDs, and the registration of all the area IDs is completed (step S8).
[0050]
The non-ejection area complement determination processing shown in the flowchart of FIG. 11 evaluates print information corresponding to the area ID registered in the inkjet recording apparatus in the non-ejection area registration processing of FIG. This is a control procedure for determining whether or not it is necessary, and is called in the discharge control procedure of the recording head during printing.
[0051]
First, the area ID registered in the non-ejection area registration processing of FIG. 10 is read from the memory 80c for one recording head (step S9). Then, the block number of the recording head corresponding to one of the read area IDs is specified (step S10). When the block number is specified, the recording information (256 bits) ejected by the nozzles constituting the block is further extracted from the raster data stored in the memory 80c (step S11). The duty is calculated from the extracted recording information by the following equation (step S12).
[0052]
(Duty) = (Number of nozzles to be ejected) / (Number of nozzles constituting block) × 100 [%]
(In fact, since it is known that 1 block = 256 nozzles, it goes without saying that the number of nozzles that simply discharge, that is, the number of bits that are “1” may be used.)
Further, the arrangement of nozzles for ejecting the recording information is prepared in advance and compared with the reference pattern stored in the ROM 80b, and the continuity of the pattern is determined in three stages of "continuous", "quasi-continuous", and "discontinuous". Classify and evaluate.
[0053]
Then, the obtained duty and pattern continuity are evaluated using predetermined thresholds (steps S13 to S16). If non-ejection complementation is not necessary, the mode for performing normal heating indicated by the heat pulse 107a for the block is set to the ejection mode. Is set to the driving gate array (step S17), and if non-ejection complementation is necessary, the mode for performing the non-ejection complementing heat indicated by the heat pulse 107b for the block is set to the gate array (step S17). Step S18).
[0054]
In this way, the heat mode of the corresponding block is determined for one area ID, and the heat mode is repeatedly determined for another area ID for the same recording head (step S19). Since the heat mode is the normal mode in the initial state, blocks to which the area ID does not correspond remain as they are.
[0055]
In addition, the determination of the heat mode in the embodiment is, in short, when there is a high possibility that the area around the position recorded by the non-ejection nozzle in the target block is a continuously ejected area, By driving with a pulse, a non-printing position due to a non-ejection nozzle is made inconspicuous, and when the possibility is low, driving with a normal heat pulse is performed. In this embodiment, the continuity of the pattern is determined, for example, when there are N or more areas to be continuously recorded in the block of interest. Here, M and N are the material and properties of the recording medium, the density of the recording head, and the color to be recorded (yellow is less noticeable due to non-discharge nozzles, and black is more noticeable. It is desirable to set adaptively according to (the value is different).
[0056]
Thus, the area ID for one recording head is processed, and the other recording heads are repeated in the same procedure (step S20).
[0057]
Then, finally, when the setting of the heat pulse for the block having the non-ejection nozzle is completed, this processing is completed, and thereafter, the processing for driving each set block is performed. As a result, the image formation for one line is completed, and this processing is sequentially performed for the next line.
[0058]
As described above, according to the present embodiment, even if a non-ejection element (nozzle) of a print head is not detected with high accuracy, the influence can be set to a minimum and the print quality can be extremely reduced. become.
[0059]
In the above-described embodiment, an example in which the ejection amount of the ink droplet is controlled by the heat pulse signal has been described. However, a piezoelectric element may be used, and in some cases, the ejection amount may be controlled by driving a plurality of times. It may be. However, in the case of a method of driving a plurality of times, since the amount of ink droplets becomes an integral multiple of a normal unit, it is preferable that the amount can be controlled with a small change amount as described in the above embodiment. .
[0060]
<Second embodiment>
In the above embodiment, the program for the above processing is stored in the ROM 80b. However, the ROM 80b is replaced by a rewritable memory (for example, an EEPROM or a flash ROM) so that the ROM 80b can be freely set by the host computer. May be.
[0061]
This example will be described with reference to FIGS. The figure shows a case where a flexible disk is used as an example of the external storage device 112b connected to the host computer 112a.
[0062]
In the present embodiment, an example is described in which each control program and data stored in the ROM 80b are loaded into the memory 80c and executed. However, the control program and data recorded on a medium such as a flexible disk may be stored in an external recording device. (Floppy (registered trademark) disk drive or the like) 112b is downloaded from the host computer 112a to the flash ROM 80b provided in the ink jet recording apparatus 112c of the embodiment. Further, a medium for recording the control program and the like, a CD-ROM, an IC memory card, etc. other than the flexible disk may be used.
[0063]
The control program is supplied by causing the flexible disk drive connected to the host computer 112a to read the flexible disk of the memory map shown in FIG. 13 and transferring it to the inkjet recording device 112c.
[0064]
FIG. 13 is a memory map when a flexible disk is used as an example of the external storage device 112b connected to the host computer 112a.
[0065]
The memory map includes a volume information storage area 113a, a directory information storage area 113b, and a print head control program (non-ejection area detection processing program, non-ejection area registration processing program, non-ejection area determination program) for each recording color component. It has a control program storage area 113c in which processing programs and the like are stored, and a data storage area 113d in which data (nozzle check patterns, print information pattern evaluation data, and the like) used in the control programs are stored.
[0066]
<Description of Third Embodiment>
Note that the present invention is not limited to the above-described embodiment.
[0067]
In the above-described embodiment, an area is set corresponding to a block that can be independently controlled by the print head, and an area including a non-discharge nozzle is specified along this area, and print information corresponding to the block is specified. It was evaluated collectively.
[0068]
However, an area depending on the control block of the recording head may be divided into smaller areas and set appropriately, and test printing may be performed so that the area including the non-ejection nozzle can be specified more specifically.
[0069]
Even if the width of the region is made narrower, it becomes difficult to specify the characters (numerals) indicating the index positions if they overlap. Therefore, as shown in FIG. 14, when printing a sample for non-ejection detection, two band patterns 140 and 141 are recorded by one recording head. In the case shown in the figure, since the number of band patterns is two, a character serving as an index of the band pattern 141 is printed at an intermediate position of the index position of the band # 140.
[0070]
As a result, in the case of the drawing, the position of the non-discharge nozzle can be set as “4” for the band pattern 140 and “E” for the band pattern 141, and as a result, the position where the non-discharge nozzle exists Can be set more finely than in the first embodiment. In the band pattern 140, non-discharge is apparently found at exactly the middle position between "4" and "5". If neither "4" nor "5" can be determined, the second band is displayed from the operation panel. It is sufficient to set only the use "E".
[0071]
With this configuration, it is possible to more accurately evaluate the recording information when the recording information recorded by the nozzles in the specified area is evaluated, so that the print quality is more effectively reduced. Is effective.
[0072]
<Other embodiments>
In the above-described embodiment, the means for controlling the ink discharge amount in the print head is realized by using two types of heat pulse signals for controlling the heater provided in the nozzle.
[0073]
However, the present invention is not limited to this mode, and may be applied to a recording head in which a plurality of heaters are provided in a nozzle and the amount of ink discharged can be changed by discharging in combination with each heater. Alternatively, it may be realized by ejecting droplets to the same pixel a plurality of times.
[0074]
As described above, any means can be applied to the present invention as long as the dot diameter recorded in a single pixel can be changed arbitrarily.
[0075]
Further, in the above embodiment, the operation panel provided in the ink jet recording apparatus main body is used as a means for registering the ID of the area specified by visual inspection of the test printing in the ink jet recording apparatus.
[0076]
However, the present invention is not limited to this mode, and the registration may be performed by a host computer to which the inkjet recording apparatus is connected. At this time, the host computer is provided with a user interface for inputting an area ID, and the input area ID through an interface for connecting an ink jet recording apparatus represented by a parallel port to the host computer. An application for registering an area ID constituted by a control unit to be sent to the recording device is incorporated.
[0077]
The interface for connecting the ink jet recording apparatus and the host computer is not limited to a local connection using a parallel port or the like, but may be any as long as the area ID can be exchanged by any communication means such as a network connection.
[0078]
As described above, any means can be applied to the present invention as long as the area ID can be notified to the inkjet recording apparatus.
[0079]
As described above in detail, according to the present embodiment, in the inkjet recording apparatus in which the ink ejection unit of the recording head is composed of a plurality of blocks and each block can control the ink ejection amount independently, Identify the area including the nozzle that occurred, scan the print information recorded by the nozzles in the identified area to determine the necessity of non-ejection complement, and when the non-ejection complement is required in the determination, By changing the ink ejection amount by the ejection control of the block corresponding to the specified area, it is possible to reduce a decrease in print quality due to non-ejection of the recording head without requiring an image reading unit.
[0080]
As a result, the ink jet printing apparatus can be continuously used without replacing the print head immediately even when some non-ejection occurs.
[0081]
【The invention's effect】
As described above, according to the present invention, even if a non-ejection port exists and its position cannot be set accurately, it is possible to reduce the influence of the non-ejection port and thereby reduce the deterioration of print quality. Become.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an inkjet recording apparatus according to an embodiment.
FIG. 2 is an enlarged cross-sectional view of a sheet feeding unit according to the embodiment.
FIG. 3 is a block diagram of a control system according to the embodiment.
FIG. 4 is a diagram illustrating a result of test printing in a normal state according to the embodiment.
FIG. 5 is a diagram showing a test print result when a non-ejection port exists.
FIG. 6 is a diagram illustrating an example of recording information in a block according to the embodiment.
FIG. 7 is a diagram for describing control of an ink liquid ejection amount in the embodiment.
FIG. 8 is a diagram illustrating a landing state by controlling an ink liquid ejection amount in the embodiment.
FIG. 9 is a flowchart illustrating a non-ejection area detection process according to the embodiment.
FIG. 10 is a flowchart illustrating a non-ejection area registration process according to the embodiment.
FIG. 11 is a flowchart illustrating a setting process of driving a non-ejection area according to the embodiment.
FIG. 12 is a system configuration diagram according to a second embodiment.
FIG. 13 is a diagram illustrating a memory map of an external storage medium according to the second embodiment.
FIG. 14 is a diagram illustrating a result of test printing according to the third embodiment.
[Explanation of symbols]
1 Recording device
2 Paper feed unit
3 Paper sending section
4 Paper output unit
7 Recording head
21 Pressure plate
22 Feed rotating body
24 spring
25 Separation pad
26 Separating claws
27 Upper guide
28 Lower Guide
29 PE sensor lever
30 Platen
31 Conveyor belt
32 Transport roller
33 Pinch roller
34 drive roller
35 pressure roller
36 Attraction force generating means
38 Cleaning Roller Pair
39 Paper holding member
41 Paper ejection roller
42 spurs
43 Output tray
52 Power supply brush
53 Holding member

Claims (12)

An image recording apparatus that discharges ink liquid from a plurality of ink liquid discharge ports provided in a recording head and that can control the amount of discharged ink,
Identifying means for identifying an area position by a plurality of continuous ink ejection ports, including a position of a non-ejection port where ink liquid cannot be normally ejected,
Control means for controlling a discharge ink liquid amount of the ink droplet discharge port group in the area based on a state of image data to be recorded by the ink droplet discharge port group included in the specified area. An image recording apparatus characterized by the above-mentioned. 2. The image recording apparatus according to claim 1, wherein the recording head is provided with an ink liquid ejection port substantially perpendicular to a conveying direction of the recording medium and having a width substantially corresponding to a width of the recording medium. Further, the apparatus further includes a predetermined pattern for determining the presence of the non-ejection port and the area position where the non-ejection port exists, and sample image recording means for recording a sample image for recording an index for determining the area position. The image recording apparatus according to claim 2, wherein 4. The image recording apparatus according to claim 3, wherein the specifying unit includes an input unit that inputs an index recorded by the sample image recording unit. 5. The image recording apparatus according to claim 4, wherein the input unit performs an input from an operation panel provided in the apparatus. The image recording apparatus according to claim 4, wherein the input unit includes a unit that receives information input by an external information processing apparatus that is a print data generation source. The image recording apparatus according to any one of claims 1 to 6, wherein the ink liquid ejection port of the recording head ejects the ink liquid by thermal energy. 8. The image recording apparatus according to claim 7, wherein the control of the discharge ink amount is performed by changing an applied heat pulse. When the non-ejection port is highly likely to be included in a range in which a continuous image is recorded, the control unit determines the amount of ink liquid ejected from an ink ejection port group included in a region including the non-ejection port. The image recording apparatus according to any one of claims 1 to 6, wherein the number is increased as compared with the time of normal recording. 10. The image recording apparatus according to claim 1, further comprising a plurality of recording heads of different color components, wherein each of the recording heads performs a process for a non-ejection port. A method for controlling an image recording apparatus capable of controlling an amount of ejected ink while discharging ink from a plurality of ink liquid ejection ports provided in a recording head,
A specifying step of specifying a region position by a plurality of continuous ink discharge ports, including a position of a non-discharge port in which ink liquid cannot be normally discharged,
A control step of controlling a discharge ink liquid amount of the ink droplet ejection port group in the area based on a state of image data to be recorded by the ink droplet ejection port group included in the specified area. A method for controlling an image recording apparatus, comprising: A storage medium that stores a program code that functions as an image recording apparatus that discharges an ink liquid from a plurality of ink liquid discharge ports provided in a recording head by reading and executing a program, and that controls an amount of discharged ink. hand,
Identifying means for identifying an area position by a plurality of continuous ink ejection ports, including a position of a non-ejection port where ink liquid cannot be normally ejected,
A program functioning as control means for controlling the amount of ink discharged from the group of ink droplet ejection ports in the area based on the state of image data to be recorded in the group of ink droplet ejection ports included in the specified area A storage medium for storing a code.

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