JP2008273014A - Recorder and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent print data from causing poor ejection, extreme fall off of ejection, or degradation of image quality in a recorder comprising an ink jet head having an array of a plurality of nozzles for ejecting ink. <P>SOLUTION: The recorder has a means for storing the position of a nozzle which cannot eject ink among a plurality of nozzles arranged in an array. For a plurality of normal nozzles located near the nonejection nozzle in the nozzle array including the nonejection nozzle, ejection data of the nonejection nozzle is assigned to the normal nozzles depending on the priority of supplementing nonejection and the position adjoining the printing position of the nonejection nozzle. A means for assigning the ejection data of the nonejection nozzle every time when the data of a column along the scanning direction is created for a predetermined number of columns is also provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a recording apparatus, and more particularly to an ink jet recording apparatus.

  For example, in an ink jet printer, if even one of the print heads having a plurality of nozzles has a non-ejection nozzle, white streaks appear on the printed product and cannot be used officially. become.

  As described above, when even one undischarge nozzle is generated in the print head, conventionally, there is no means for dealing with it other than stopping the use of the undischarge print head. If an undischarge nozzle is found in the print head manufacturing stage, there is no method other than discarding the undischarge print head including the undischarge nozzle. In addition, if a discharge failure nozzle is generated in the print head after the printer has reached the user's hand, the user cannot cope with anything other than buying a new print head.

  As described above, the situation where undischarge nozzles are generated in the print head imposes an economic burden on both the printer manufacturer and the user.

  In addition, in recent printers, the number of print nozzles is very large, and 512 nozzles are provided for each color. If these are provided for six colors, the total number of nozzles is 3072. If the number of nozzles increases in this way, the probability of non-discharge nozzles per printer increases, so the economic burden on both the printer manufacturer and the user side increases.

  In order to avoid such a situation, several printer manufacturers have recently proposed proposals for so-called non-discharge complementation that complements the print data of the non-discharge nozzles in the print head (see, for example, Patent Document 1). ). The invention described in Patent Document 1 is an invention in which print data assigned to a discharge failure nozzle is moved according to a specified discharge failure complement priority for several normal print nozzles above and below the discharge failure nozzle. is there. As a result, the print data of the discharge failure nozzle is complemented and normal printing is possible.

  When recording is performed using a print head having a plurality of nozzles, the quality of the recorded image often depends on the performance of the print head alone. Slight differences that occur during the recording head manufacturing process, such as the shape of the discharge port of the print head and the variation of the electrothermal transducer (discharge heater), affect the amount of discharged ink and the direction of the discharge direction. As a result, the image quality is deteriorated as the density unevenness of the image formed.

  In order to avoid such a situation, a recording method using multi-scan recording is performed. For example, in a print head having 128 nozzles, when printing is performed by multi-scanning of two scans, the 128 nozzles of the print head are divided into groups of 64 upper nozzles and 64 lower nozzles. The dots printed by one scan by one nozzle are obtained by thinning out prescribed image data by about half according to a predetermined image data arrangement. Then, based on the remaining half of the image data at the time of the second scan, the dots are embedded in the places where the dots were not formed by the first scan, thereby completing the printing of the 64-pixel unit area. When such a recording method is used, the influence on the print image unique to each nozzle is halved, so that the deterioration of the image quality is alleviated.

  When this recording method is used, the image data is divided in the first scan and the second scan so as to make up for each other according to a predetermined arrangement (mask). Usually, this image data array (thinning pattern) is most commonly used in such a manner that it becomes a houndstooth pattern for each vertical and horizontal pixel. In the unit printing area, printing is completed by a first scan for printing a staggered lattice and a second scan for printing an inverted staggered lattice.

  Further, an ink jet printer discharges and ejects ink droplets (recording liquid), which is a fluid, from a discharge port of a print head and attaches it to a print material for printing. Accordingly, discharge failure occurs when various adverse hydrodynamic phenomena are used at or near the limit printing speed of the print head. Further, since ink is a liquid, its physical state such as viscosity and surface tension always varies greatly depending on the environmental temperature and the ink standing time. Therefore, even if printing is possible in a certain state, printing may be difficult due to an increase in negative pressure due to a decrease in the ambient temperature or the remaining amount of ink in the ink tank.

  If it is used near the limit discharge cycle, ink refilling (refilling) to the flow channel will not be in time, the next discharge moving body will start before refilling, causing discharge failure, and the discharge amount is extremely There is a problem that it drops.

In other words, multi-scanning recording using a houndstooth image data array (thinning pattern) is sufficient to keep ink refilling (refilling) in high-speed printing, and to prevent image quality deterioration due to variations in the print head. It is an effective means.
JP 2005-96424 A

  However, when the non-discharge nozzles are complementarily controlled, the print data of the non-discharge nozzles is the print data assigned to the non-discharge nozzles in accordance with a predetermined non-discharge complement priority for several normal print nozzles. Move data. Therefore, the print data after the non-discharge nozzle complementary control may not be in a houndstooth image data arrangement. In this case, the print data causes a discharge failure and the discharge amount is extremely reduced. There is a problem that the quality of the image may deteriorate.

The present invention provides a printing apparatus including an inkjet head having a nozzle row in which a plurality of nozzles that eject ink are arranged, print data does not cause ejection failure, and the ejection amount does not extremely decrease. An object of the present invention is to provide a recording apparatus in which the quality of an image does not deteriorate.

The present invention is a recording apparatus that uses an inkjet head having a nozzle row in which a plurality of nozzles that eject ink are arranged, and that records while scanning the inkjet head on a recording medium. The present invention further includes undischarge nozzle position storage means for storing the position of an undischarge nozzle that cannot discharge ink among the plurality of nozzles arranged in the nozzle row. The present invention relates to a discharge failure complement priority order and a position adjacent to a position where the discharge failure nozzle prints for a plurality of normal nozzles located in the vicinity of the discharge failure nozzle in a nozzle row including the discharge failure nozzle. Accordingly, data to be discharged by the discharge failure nozzle is assigned to the normal nozzle. In addition, the present invention is a recording apparatus having a data allocating unit that allocates data to be ejected by the discharge failure nozzle every time a predetermined number of columns of column data along the scanning direction are created.

According to the present invention, in a recording apparatus including an ink jet head having a nozzle row in which a plurality of nozzles that discharge ink are arranged, the print data does not cause a discharge failure and the discharge amount is extremely reduced. Therefore, the image quality is not deteriorated.

  The best mode for carrying out the invention is the following embodiment.

[principle]
First, the principle necessary for realizing the recording apparatus PR1 that is Embodiment 1 of the present invention will be described.

  FIG. 1 is a diagram schematically illustrating a printing state in the recording apparatus PR1 according to the first embodiment when there is nozzle discharge failure.

  FIG. 1 is a diagram illustrating a specific nozzle row 11 extracted from the print head 10.

  In this nozzle row 11, as shown in FIG. 1, normal nozzles 12 (many are provided) and undischarge nozzles 13 (assuming that there is only one in the nozzle row 11). And exist.

  The print image 20 is a print image created on the paper surface by the nozzle row 11 of the print head 10. At this time, the print head 10 prints the print image 20 while moving in the main scanning direction 21. At this time, the ejection timing of the print head is electrically determined, and the nozzle row 11 of the print head 10 forms the print image 20 while keeping the prescribed interval = column interval 22 with respect to the main scanning direction 21. To do. The print image 20 is also formed in a direction orthogonal to the main scanning direction 21 while maintaining a predetermined interval = raster interval 23. Note that the specified interval = raster interval 23 usually follows the mechanical interval of the nozzle rows 11 in many cases. A print image 20 shown in FIG. 1 is a print image when the print head 10 scans once in the main scanning direction 21.

  In the print image 20, the normal nozzle 12 discharges to a position 25 where the normal nozzle should be printed. In addition, the undischarge nozzle 13 is supposed to be discharged at a position 26 where the undischarge nozzle 13 is to be printed (a position where printing is not performed), but cannot be discharged at that position.

  The purpose of the first embodiment is to make it appear as if the undischarge nozzle 13 is to be printed (a position where printing was not performed) as if it was printed without impairing the prescribed image data arrangement (staggered arrangement).

  First, using only the complement target area 24, a state of complementing that the discharge failure nozzle 13 cannot discharge to the position 26 to be printed in the complement target area 24 will be described.

  FIG. 2 is a diagram simply illustrating the principle of discharge failure complement according to the first embodiment of the present invention.

  FIG. 2A is a diagram showing the complement target area 24 shown in FIG.

  The complement target area 24 includes a position where the normal nozzle 12 is to be printed and a position where the undischarge nozzle 13 is to be printed.

  FIG. 2 (2) shows a position other than the position at which the undischarge nozzle 13 should be printed in order to complement that the undischarge nozzle 13 cannot discharge at the position to be printed in the complement target area 24 shown in FIG. 2 (1). It is a figure which shows discharge failure complement priority.

  At this stage, the discharge failure complement priority number is assigned to the position where the discharge failure complement priority is given regardless of whether the normal nozzle 12 has data to be printed. In the example shown in FIG. 2B, numbers 1, 2, 3, 4 are simply given in order from the top of the figure. This number may be in another order, such as 2, 4, 1, 3, etc.

  FIG. 2 (3) is a diagram illustrating a state in which discharge failure dots are complemented according to discharge failure complement priority given in FIG. 2 (2).

  Without regard to the pattern of the printing dots in the complementing target area 24 as shown in FIG. 2 (1), what kind of non-discharge dots are complemented in each of the three cases. This will be explained.

  First, a case (non-discharge complementation case) 1 that complements that the discharge failure nozzle 13 cannot discharge to a position to be printed will be described.

  The non-discharge complement case 1 is a case where there are 0 print data and data that has not been printed by one undischarge nozzle. In this case, the data that has not been printed due to the one discharge failure is moved to the highest discharge failure complement priority position (that is, dot complementation is performed). In the discharge failure complement case 1, it is the position of the top dot (= dot having discharge failure complement priority 1) in the figure.

  Next, the discharge failure complement case 2 will be described.

  Undischarge complementation case 2 shown in FIG. 2 (3) is a case in which one print data exists in the previous column and data that is not printed by one undischarge nozzle exists. The data that is not printed due to the one discharge failure is originally complemented by the dot at the top of the drawing (= data having discharge failure complement priority 1). However, since the print data exists in the previous column (that is, the adjacent position that does not have the staggered arrangement), the discharge failure complement priority other than the discharge failure complement priority 1 has the highest discharge failure complement priority. Moved to a higher position. In discharge failure complement case 2, it is the second position from the top in the figure (= position having discharge failure complement priority 2).

  Next, the discharge failure complement case 3 will be described.

  The undischarge complement case 3 is a case in which one print data exists in the previous column, and there is one print data and data that is not printed by one undischarge nozzle. The data that is not printed by the discharge failure nozzle includes discharge failure complement priority 1 removed for the same reason as discharge failure complement case 2, and discharge failure complement priority 2 removed because print data exists. Among the discharge failure complement priorities excluding, the shift is made to the highest discharge failure complement priority. In discharge failure complement case 3, that is the second position from the bottom in FIG. 2 (= position of discharge failure complement priority 3).

  As described above, the discharge failure complement priority given in the process of FIG. 2B and the print data in the complement target area 24 are observed. Then, non-discharge complementation is performed by an algorithm that performs non-discharge complementation at a position with the highest discharge failure complement priority among the positions of data that can be printed by the normal nozzle 12 and is not printed. Do (striking ink).

  FIG. 2 (4) is a diagram showing a state in which discharge failure complementation is performed on the original example of FIG. 2 (1) by applying this algorithm.

  When the discharge failure complement priority is given in the order of FIG. 2 (2), print data exists in the position of discharge failure complement priority 1 and the previous column in FIG. 2 (1). In this case, the discharge failure complement priority positions that can be complemented are 3 and 4, so discharge failure complement is performed at the highest discharge failure complement priority position 3.

  The principle necessary for realizing the first embodiment will be briefly summarized. The first principle is that if there is an undischarge nozzle 13 in the print head and there is data to be printed at that position, the print data is referred to the arrangement of print column data before and after the discharge nozzle 13 This is the principle of moving to a nearby normal nozzle. The second principle is that the movement of the print data is determined by the relationship between the predetermined discharge failure complement priority and the print data at the position of the normal nozzle 12 where discharge failure complement should be performed. is there. According to the third principle, when non-discharge complementation is realized by the first and second principles, the complement to the non-discharge nozzle 13 is completed while the print head scans once in the main scanning direction 21. is there.

  The above is the principle necessary for realizing the first embodiment.

[Configuration and data flow]
FIG. 3 is a diagram showing an internal configuration of the ASIC 3 and an outline of the data flow.

  Although the actual printer ASIC 3 has a complicated structure that cannot be completely written in FIG. 3, FIG. 3 shows only the internal configuration of the portion related to the discharge failure complement function related to the first embodiment.

  First, in addition to the ASIC 3, there are two elements that should be added to facilitate understanding of the function when explaining the data flow of the discharge failure complement function.

  One element is the personal computer PC and the print head 10. The personal computer PC exists outside the printer having the discharge failure complement function of the first embodiment, and transfers print data to the printer, more precisely, to the data receiver of the ASIC 3. Further, the print head 10 is a head for creating a print output as a product of the printer. As described in the above principle, the print head 10 is mixed with the normal print nozzle and the undischarge nozzle 13. Exists. Further, data for controlling the operation of the print head 10, that is, print data, ejection pulse signals, and the like are generated inside the ASIC 3.

  Next, the inside of the ASIC 3 will be described.

  First, main blocks will be described. The CPU 34 is a CPU that supervises and manages the overall operation of the ASIC 3. The SD-RAM 35 is a main memory of the printer system according to the first embodiment. The memory need not be an SD-RAM, and may be a D-RAM or an S-RAM as long as it belongs to the definition of RAM, and a memory other than the SD-RAM may be used instead. The other blocks in the ASIC 3 are so-called random logic portions, which realize operations specific to the printer and operations specific to the discharge failure complement function of the first embodiment.

  Next, the random logic part will be described.

  The interface unit 41 is an interface unit that receives data transferred from the personal computer PC. For example, the interface unit 41 is responsible for capturing data in accordance with an interface protocol such as IEEE 1284, USB, IEEE 1394, etc., and generating data in a form that is easy for the ASIC 3 to handle. The form that the ASIC 3 can easily handle is a form in which the data is shaped in units of 1 byte.

  Data taken by the interface unit 41 into the ASIC 3 is sent to the reception data control unit 42. The responsibility of the reception data control unit 42 is to receive the data received by the interface unit 41 and store it in the SD-RAM 35. A portion of the SD-RAM 35 that is controlled by the reception data control unit 42 is referred to as a reception buffer.

  The data stored in the SD-RAM 35 by the reception data control unit 42 is read into the print data generation unit 44 according to the timing of each print control, and print data is generated. Normally, the print data generation unit 44 is divided into various functions such as an HV conversion unit, a data development unit, and a multi-pass mask control unit, depending on its role.

  Further, when each of the above functions accesses the SD-RAM 35 and performs data processing by the unique function, the access area in the SD-RAM 35 is set as a work buffer, a print buffer, a mask buffer, or the like. Call it with a different name. However, in this case, the detailed description of these functions is not related to the description of the discharge failure complement function, so the above functions are collectively treated as a “print data generation unit”.

  The print data created by the print data generation unit 44 is stored in the print data storage S-RAM 45. This S-RAM 45 for storing print data is not indispensable in terms of the system, but recent printers often make a large amount of print data to improve the printing speed. In this way, print data is often temporarily stored in a memory that can be accessed at high speed such as an S-RAM. A D-RAM memory is not suitable because it takes too much access time.

  It is also very important that the print data handled here is data that has been subjected to various data processing such as multi-pass, INDEX data expansion, and mask processing. Is sent to the print head controller, the data can be printed immediately. The discharge failure complement function of the first embodiment further performs discharge failure complement processing on this data.

  The print data reading unit 46 reads the print data storage S-RAM 45. At this time, if the discharge failure nozzle 13 does not exist in the print head 10, the data read by the print data reading unit 46 is directly sent to the print head control unit 47. The print head controller 47 performs hardware control specific to the print head 10 such as transferring the received print data to the print head 10 and transmitting a heat pulse signal to the print head 10.

  There is also a print timing generator 48 that generates various print timings from the encoder signal 49. The print timing generation unit 48 generates signals from the encoder signal 49 at appropriate intervals. Then, the print data generation unit 44, the print data reading unit 46, the print head control unit 47, and the discharge failure complement data reading unit 57 described later can exchange data at an appropriate timing.

  Next, the part regarding the discharge failure complement function of the first embodiment will be described. The block related to the discharge failure complement function is a discharge failure complement block 50 inside the ASIC 3.

  First, the discharge failure information storage unit 51 is a memory that sets in which nozzle position in the print head the discharge failure nozzle 13 is located. This setting is performed by the CPU 34. The information on the discharge failure nozzle 13 set in the discharge failure information storage unit 51 is transferred to the discharge failure complement data extraction timing generation unit 52, the print data reading unit 46, and the data generation unit 58 after discharge failure complement. Is done.

  The discharge failure complement data extraction timing generation unit 52 generates a discharge failure complement data extraction timing signal based on the transferred data. That is, the print data generation unit 44 can determine which nozzle data in the print head 10 is currently generated (regardless of whether it is normal or undischarged) and written in the print data storage S-RAM 45. Therefore, information indicating the relationship between the currently handled print data and the nozzles in the print head 10 is received from the print data generation unit 44. As a result, whether the discharge data of the non-discharge nozzle 13 is currently handled or the discharge data of the nozzle position where the upper and lower non-discharge complementation in the vicinity of the non-discharge nozzle 13 described in the above principle is to be performed. It can be determined whether or not there is. Of course, if there is no discharge failure nozzle 13 in the print head, the discharge failure complement data extraction timing generation unit 52 outputs no signal.

  Based on this data, the discharge failure complement data extraction timing generation unit 52 can notify the discharge failure complement data extraction unit 53 of the timing for fetching discharge failure complement data. The discharge failure complement data is discharge data of the discharge failure nozzle 13, print data at the normal nozzle 12 position where discharge failure complement should be performed, and column data before and after discharge failure complement.

  Since the discharge failure complement data extraction unit 53 is connected to the signal line of the print data output from the print data generation unit 44, the discharge failure complement data extraction unit 53 includes the print data in accordance with the timing notified by the discharge failure complement data extraction timing generation unit 52. From this, only the discharge failure complement data is extracted.

  The extracted discharge failure complement data is transferred to the discharge failure complement algorithm execution unit 60. The discharge failure complement algorithm execution unit 60 is a block that performs discharge failure complement data calculation described in the above principle.

  According to the above principle, in order to perform discharge failure complement data calculation, discharge failure complement priority is required. The discharge failure complement priority setting unit 55 in the discharge failure complement block 50 transfers discharge failure complement priority data to the discharge failure complement algorithm execution unit 60. The discharge failure complement priority setting unit 55 has a function capable of setting discharge failure complement priority by setting of the CPU 34. By providing such a discharge failure complement priority setting unit 55, the discharge failure complement priority can be flexibly changed by firmware even after the ASIC 3 is designed and manufactured.

  Since the discharge failure complement algorithm execution unit 60 is an important function in the first embodiment, it will be described in detail separately.

  FIG. 4 is a diagram illustrating a specific example of the discharge failure complement algorithm execution unit 60.

  As described above, the discharge failure complement algorithm execution unit 60 receives discharge failure complement priority data, extracted discharge failure complement data, and column data before and after discharge failure complement. The extracted discharge failure complement data is discharge data of the discharge failure nozzle 13 and print data of the position of the normal nozzle 12 to be discharged failure complement.

  To explain, we make several assumptions.

  First, as shown in FIG. 4, as described in the above principle, non-discharge complementation is performed for the positions of the normal nozzles 12 of the upper and lower two nozzles of the non-discharge nozzle 13 (instead of the non-discharge nozzle 13, normal operation is performed). Nozzle 12 ejects ink). In addition, the discharge failure complement data extracted for this position is considered to have print data only at the top position as shown in FIG. Whether there is print data at the position of the undischarge nozzle 13 will be discussed later. Furthermore, the discharge failure complement priority is set for the positions of the normal nozzles 12 that perform the discharge failure complementation, that is, four locations. As shown in FIG. 4, the order of 1, 2, 3, 4 from the top is set. Suppose that it was granted.

  Next, components of the discharge failure complement algorithm execution unit 60 and realization of the algorithm will be described.

  The three types of data input to the discharge failure complement algorithm execution unit 60, discharge failure complement priority data, extracted discharge failure complement data, and column data before and after discharge failure complement, To the extraction unit 61. The purpose of this block is to extract only the discharge failure complement priority order in which there is no print data from the normal nozzles 12 and discharge failure complement is possible from the discharge failure complement priority data.

  As shown in FIG. 4, in the discharge failure complement priority data, the print data exists at the position of rank 1 and next to the discharge failure complement priority of 3 in the previous column. The discharge failure complement priority that can be set to 2 and 4 is 2. That is, print data is not given to two adjacent positions. That is, ink is not applied to both of the two adjacent positions.

  The extracted discharge failure complement priority data capable of discharge failure complement is transferred to the discharge failure complement priority determination unit 62. Then, only one highest discharge failure complement priority is determined from the discharge failure complement priorities for which discharge failure complement is possible. In the example shown in FIG. 4, the discharge failure complement priority that enables discharge failure complement is 2 and 4, and the highest discharge failure complement priority is 2 among them.

  Finally, the discharge failure complement data synthesis unit 63 receives data processing, and discharge failure complement is completed. The first responsibility of the block is one of the data of the highest discharge failure complement priority position output by the discharge failure complement priority determination unit 62 and the original input signal of the discharge failure complement algorithm execution unit 60. It is to synthesize the extracted discharge failure complement data. Then, print data after non-discharge complementation is created.

  However, the second responsibility of the block is to determine whether or not print data originally exists at the position of the discharge failure nozzle 13. If there is print data at that place, as described in the first responsibility, print data after discharge failure compensation is created, and the created data is output to the discharge failure complement algorithm execution unit 60. Output as. Conversely, if there is no print data at that location, the undischarge complementing algorithm execution unit 60 outputs the extracted undischarge complementing data as it is.

  The above is the function and configuration of the discharge failure complement algorithm execution unit. For reference, the algorithm given by this block (= discharge failure complement algorithm itself) can be created with only combinational circuits, and does not require any sequential circuits such as FFs that cause an increase in gate amount. . That is, it can be said that the algorithm is very simple and can be realized at low cost.

  Next, returning to FIG. 3 again, the continuation will be described.

  The discharge failure complemented data, which is a product of the discharge failure complement algorithm execution unit 60, is written to the discharge failure complement data S-RAM 56. The discharge failure complement data S-RAM 56 is a memory corresponding to the print data storage S-RAM 45 storing print data.

  Since the non-discharge complemented data is also the final print data, it may be stored in the print data storage S-RAM 45. However, if this is done, the write data storage S-RAM 45 has two write blocks, the print data generation unit 44 and the discharge failure complement algorithm execution unit 60, and bus arbitration and conflicts are expected. On the basis of this, there is a concern about performance degradation as a printer system, so a separate S-RAM is provided exclusively for non-discharge complemented data. However, if the capability of the printer system is dramatically improved in the future, it may be possible to use the print data storage S-RAM 45 together.

  Next, the discharge failure complemented data written in the discharge failure complement data S-RAM 56 is read by the discharge failure complement data reading unit 57 at a prescribed timing. The “specified timing” is synchronized with the print data reading unit 46.

  That is, first, the print data storage S-RAM 45 includes both the print data of the normal nozzle 12 and the print data of the discharge failure nozzle 13. However, the discharge failure complement data S-RAM 56 stores only nozzle print data around the discharge failure nozzle 13 (in this embodiment, “upper and lower 2 nozzles”). The aim of the first embodiment is finally to appropriately mount the data of the discharge failure complement data S-RAM 56 on the data of the print data storage S-RAM 45. The data in the print data storage S-RAM 45 is print data including the print data of the normal nozzles 12 and the undischarge nozzle 13. Further, the data in the discharge failure complement data S-RAM 56 is nozzle print data around the discharge failure nozzle 13 and is also data after discharge failure complement is performed.

  Therefore, when the print data reading unit 46 reads nozzle data related to discharge failure complement, the corresponding data is also read from the discharge failure complement data S-RAM 56, and the two are appropriately mounted. It is necessary to. It is possible to read this at a disjoint timing and separately create a sequential circuit for appropriately mounting the above two later. In this case, however, the device for the sequential circuit becomes large. Therefore, it is not a desirable means from the viewpoint of creating a system on a small scale, simply and inexpensively.

  Therefore, the discharge failure complement data reading unit 57 needs to read out the discharge failure complemented data in a synchronized manner based on the signal from the print data read unit 46. In addition, the print data reading unit 46 determines whether or not the print data that it is currently reading relates to discharge failure complement, and then outputs a signal to the discharge failure complement data read unit 57 in order to output a discharge failure. Information on the discharge failure nozzle 13 output by the information storage unit 51 is necessary.

  Next, the discharge failure complement data read by the discharge failure complement data reading unit 57 is transferred to the data generation unit 58 after discharge failure complement together with the print data read by the print data reading unit 46 in synchronization therewith. The non-discharge complemented data for the print data is implemented. According to the above procedure, the print data must be nozzle position data related to discharge failure complement.

  FIG. 5 is a diagram illustrating a configuration of a data generation unit after discharge failure complementation that is an element in the discharge failure complement system according to the first embodiment.

  Briefly, first, as described above, non-discharge complemented data and print data are input. Next, the non-discharge complemented data is expanded to the same number of bits as the print data. Normally, in a printer, print data is handled in units of multiples of 8, such as byte or word. On the other hand, the non-discharge complemented data may have a smaller number of bits, and in this case, it is necessary to match the same number of bits as the print data. In the first embodiment, the undischarge nozzle 13 is 1 bit, and the nozzles targeted for non-discharge complementation are 4 bits, which is 5 bits in total.

  In the first embodiment, as shown in FIG. 5, assuming that the print data is handled with 8 bits (= 1 byte), the non-discharge complemented data needs to be expanded from 5 bits to 8 bits. The expansion method is simple. Based on the position information of the discharge failure nozzle 13 transferred from the discharge failure information storage unit 51, it is determined which position is to be expanded, and “0” ( (NULL data). In this way, the non-discharge complemented data and the print data which have been bit-extended are sent to the bit OR circuit 581 to perform a logical OR operation between the respective bits. It is output as the output of the data generation unit 58 after the discharge failure complement.

  If you look closely at FIG. 5, there are undischarge-complemented data (after bit expansion) that is the input of the data generation unit 58 after undischarge complementation and the output of the data generation unit 58 after undischarge complementation. The print data in a state where the non-discharge complemented data is mounted is exactly the same data.

  In this case, it seems that the bit OR circuit 581 is not necessary, but there are cases where this is not the case. For example, according to the assumption of the first embodiment, in the same 1-byte print data, the print data of the adjacent nozzles are drawn so as to be adjacent to each other in the same manner as the form of the nozzles in the print head 10. It is. However, depending on the printer system, the print data of adjacent nozzles may be in different 1-byte print data. This state is as depicted in the print head 10 and the nozzle row 11 in FIG.

  Since this is based on the difference in the form of the print head and the drive method, it cannot be generally defined that the print data has such a format. Therefore, processing (extracting the necessary bits) and expansion (filling with “0” in accordance with the bit width of the print data) are required for the non-discharge complemented data according to the print data format. . In this case, since the position and timing at which nozzle data related to discharge failure complement appears in the print data, the print data reading unit 46 and the discharge failure complement data reading unit 57 cooperate with each other. Need to work.

  In this way, the created print data on which the discharge failure complement data is mounted is transferred to the print head control unit 47, and the print head control unit 47 prints in accordance with the protocol of the print head 10. This operation is exactly the same as when there is no discharge nozzle 13.

According to the first embodiment, the processing engine for non-discharge complementation is realized with a very simple and inexpensive configuration. Further, since the discharge failure complement process is performed in the same print path as that for printing the data assigned to the discharge failure nozzle 13, there is no print pass only for discharge failure complement. Since non-discharge complementation processing is performed in the same nozzle row, for example, even if another nozzle row (nozzle row of a different color) has another non-discharge, print data for undischarge nozzles in that nozzle row is created. Each time the processing algorithm similar to the above is performed, the discharge failure complement processing can be performed.

[Improvement to Example 1]
Example 1 provides an almost complete solution to the conventional problem. However, if the first embodiment is mounted on a printer as it is, there is a concern that the following problems may occur.

  That is, when non-discharge complementation is performed in this manner, the lifetime of only nozzles having a high discharge failure complement priority is shorter than the lifetime of other normal nozzles 12.

  Embodiment 2 of the present invention attempts to provide a more complete discharge failure complement algorithm by preventing the concern that the life of a nozzle having a high discharge failure complement priority will be shorter than the life of other normal nozzles 12 in advance. Is.

[principle]
First, the principle necessary for realizing the second embodiment of the present invention will be described.

  FIG. 6 is a diagram illustrating a print image 20a when there is nozzle discharge failure in the second embodiment of the present invention.

  In terms of contents, it should be almost the same as the print image 20 shown in FIG. The changed content is that the complement target area 24 shown in FIG. 1 is for one column and five rasters, but the complement target area 70 shown in FIG. 6 is for four columns and five rasters.

  A state in which the discharge failure nozzle discharge position in the complement target area 70 is complemented using only the complement target area 70 will be described.

  FIG. 7 is a diagram simply illustrating the principle of non-discharge complementation in the second embodiment of the present invention.

  FIG. 7A is a diagram in which one complementation target area 70 is extracted from the print image 20a shown in FIG.

  This includes four printing positions and a position that has not been printed due to undischarge. Here, for convenience of explanation, the ejection failure nozzle ejection positions in each column are referred to as T1, T2, T3, and T4.

  7 (2) shows a position where the undischarge nozzle should print in a place other than the position where the undischarge nozzle should print in order to complement the position where the undischarge nozzle in FIG. 7 (1) should print. It is a figure which shows the state to which the discharge failure complement priority for complementation is attached | subjected.

  At this stage, the discharge failure complement priority number is assigned to the position where the discharge failure complement priority is given, regardless of whether there is print data. This content also corresponds to the description of FIG. 2 (2), but the difference is that a different discharge failure complement priority is given to each of the positions T1, T2, T3 and T4 where the discharge failure nozzle should be printed. This is the point. In addition, since the complement target area 70 is increased from 4 to 16 positions, the discharge failure complement priority is 1 to 4 in the example shown in FIG. 2 (2), but the example shown in FIG. 7 (2). Then, undischarge complementation priority is a point which is 1-16. As this non-discharge complementation priority, the same pattern as the positions T1, T2, T3, and T4 where the non-discharge nozzles should be printed may be given, but in order to meet the purpose of the second embodiment, FIG. As shown in the example of (2), it is desirable to give different patterns.

  FIG. 7 (3) is a diagram illustrating a state in which the position where the ejection failure nozzle should be printed is complemented in accordance with the ejection failure complement priority shown in FIG. 7 (2).

  Without considering the pattern of the printing dots in the complementing target area 70 as shown in FIG. 7 (1), for some cases, the positions T1, T2, A description will be given of what processing is performed for non-discharge complementation at T3 and T4.

  First, consider a case where print data exists at the position of the discharge failure nozzle discharge position T1. T1 discharge failure complement (case 1) is an example. The situation shown in this figure is a case where there are 0 print data and print data that is not printed due to one discharge failure.

  In this case, the data that is not printed due to the one discharge failure is moved to the position with the highest discharge failure complement priority. That is, the data is complemented. In case 1, nozzles having discharge failure complement priority 1 complement.

  Next, another example, T1 discharge failure complement (case 2) will be described.

  The situation shown in FIG. 7 is a situation in which there is one print dot and a dot that has not been printed due to one discharge failure. One piece of print data corresponds to a position where discharge failure complement priority 1 is given. In this case, the data that is not printed due to the one discharge failure is the discharge failure complement priority order excluding the discharge failure complement priority order 1 and the discharge failure complement priority order 2 that is the adjacent dot position. Moved to the highest discharge complement priority position. In case 2, the nozzle having discharge failure complement priority 3 is complemented.

  Next, consider a case where a print dot exists at the discharge failure nozzle discharge position T2.

  Here, it is assumed that the discharge failure complement process of T2 must be performed after the process of T1 is completed. T2 discharge failure complement (case 1) is an example. The situation shown in FIG. 7 is a case where there are 0 print dots and data that is not printed due to one discharge failure. In this case, the data that is not printed due to the one discharge failure is complemented as it is at the highest discharge failure complement priority position. In case 1, nozzles having discharge failure complement priority 1 complement.

  Next, another example of T2 discharge failure complement (case 2) will be described. The situation shown in FIG. 7 is a case where there is one print data in the column immediately before the target complement target area 70 and there is data that is not printed due to one non-discharge.

  In this case, the data that is not printed due to the one undischarge is the undischarge complement priority among the undischarge priority except the undischarge complement priority 1 adjacent to the print position of the previous column. Is moved to the highest position. In case 2, data having discharge failure complement priority 2 is complemented.

  Next, another example of T2 discharge failure complement (case 3) will be described.

  The situation shown in FIG. 7 is a situation where there is one print dot and one complementary data (assumed that it occurred at the time of the T1 process performed before the T2 process). One piece of complementary data exists at a position where discharge failure complement priority 1 is given. In this case, the data that is not printed due to the one discharge failure is discharge failure complement priority among discharge failure priority orders excluding discharge failure complement priority order 1 and discharge failure priority complement priority order 2 that is an adjacent position. Moved to the highest ranking position. In case 2, data having discharge failure complement priority 3 performs discharge failure complement.

  Hereinafter, after performing the discharge failure nozzle discharge position T1 → T2 and discharge failure complement processing, processing is performed in the order of discharge failure nozzle discharge position T3 → T4 using the same algorithm as described above.

  In FIG. 7 (3), in the T3 discharge failure complement diagram, if there is print data at the discharge failure nozzle discharge position T3, complementary dots performed at the discharge failure nozzle discharge positions T1 and T2, and the original print data As a result, the complement processing is performed. In the example shown in FIG. 7 (3), the supplement is performed at the position where the discharge failure complement priority 1 is given. If there is no print dot at the discharge failure nozzle discharge position T3 (if there is no data to be printed), nothing is done.

  In the example showing T4 discharge failure complement in FIG. 7 (3), if print data exists at discharge failure nozzle discharge position T3, complementary data performed at discharge failure nozzle discharge positions T1, T2, and T3. Then, the complementary processing is performed while avoiding the original print data. In the example shown in this figure, complementation is performed at a position where discharge failure complement priority 1 is given. If there is no print data at the discharge failure nozzle discharge position T4, nothing is done.

  FIG. 7 (4) is a diagram showing a state where non-discharge complementation is performed on the original example of FIG. 7 (1) by applying the above algorithm.

  The example of T1 discharge failure complement shown in FIG. 7 (4) is an example in which discharge failure complement of the discharge failure nozzle discharge position T1 is performed. Print data exists at the discharge failure nozzle discharge position T1, and print data exists at the discharge failure complement priority 1 position. Therefore, the data to be printed at the discharge failure nozzle discharge position T1 is moved to the discharge failure complement priority 3 position excluding the discharge failure complement priority 1 and the discharge failure complement priority 2 which is the adjacent position.

  FIG. 7 (4) shows the state of processing (T2 undischarge complementation) at the undischarge nozzle discharge position T2.

  However, since there is no print data at the undischarge nozzle discharge position T2, no complement processing is performed.

  FIG. 7 (4) shows the state of the undischarge nozzle discharge position T3 (T3 undischarge complementation) performed next.

  A print dot exists at the discharge failure nozzle discharge position T3, and print data exists at the position of the previous column of discharge failure complement priority 1. Therefore, when the highest priority is searched for among the discharge failure priorities excluding discharge failure complement priority 1, discharge failure complement priority 2 is empty. Therefore, the position to be printed instead of the discharge failure nozzle discharge position T3 is moved to the discharge failure complement priority 2 position.

  FIG. 7 (4) shows the state of the next processing for the undischarge nozzle discharge position T4 (T4 undischarge complementation). However, since there is no print data at the position T4 where the undischarge nozzle is to be printed, no complement processing is performed.

  The principle necessary for realizing the second embodiment will be summarized. In the first embodiment, when there is an undischarge nozzle 13 in the print head and there is data to be printed at that position, the print data is moved to upper and lower normal nozzles near the undischarge nozzle 13. In the first embodiment, the upper and lower normal nozzles in the vicinity of the undischarge nozzle 13 are assumed to be two upper and lower nozzles of the undischarge nozzle 13.

  However, in the second embodiment, the complement area is increased and complement is performed within an area of several columns (in this principle, it is assumed that there are four columns). The discharge failure complement priority can be set for each position where discharge nozzles should print.

  The above is the description of the principle necessary for realizing the second embodiment.

[Configuration and data flow chart]
Next, a configuration necessary for realizing the second embodiment and a data flowchart thereof will be described.

  Since the basic operation is almost the same as that of the first embodiment, the description will be limited to the difference.

  First, it is the same as in the first embodiment that a component as a printer is required.

  Also, the internal components of the ASIC 3, that is, the elements shown in FIG. First, the difference is the discharge failure complement priority setting unit 55, which has data in a form different from the discharge failure complement priority data of the first embodiment. The difference in the discharge failure complement priority data is different from the discharge failure complement priority order shown in FIG. 7, unlike the discharge failure complement priority order shown in FIG.

  Another difference is the contents of the discharge failure complement algorithm execution unit 60. Since this part is a fundamental part in the second embodiment, it will be described with reference to FIG.

  FIG. 8 is a diagram illustrating individual elements and a data flow therebetween in the second embodiment.

  Before describing, there is an assumption that should be set for the discharge failure complement of the second embodiment. That is, as shown in FIG. 8, similarly to the description of the above principle, the discharge failure complement is set in the position of the normal nozzles 12 of the upper and lower nozzles of the discharge failure nozzle 13 and the range of 4 columns. Further, as described in the above principle, the discharge failure complement process is set so that the discharge failure nozzle discharge positions are processed in the order of T1 → T2 → T3 → T4.

  First, the discharge failure complement algorithm execution unit 60 receives a signal from the discharge failure complement data extraction timing generation unit 52 and takes in discharge failure complement data. Unlike Example 1, here, after fetching discharge failure complement data over a range of 6 columns, operation must be performed for 4 columns, and sequential control is required. Therefore, it is necessary to have the discharge failure complement processing algorithm management unit 81 that controls the entire operation. This block receives a signal from the discharge failure complement data extraction timing generation unit 52, and outputs a signal to the discharge failure complement processing data latch unit 82 to latch discharge failure complement data based on the signal. . At the same time, the discharge failure complement processing algorithm management unit 81 starts discharge failure complement processing when the discharge failure complement data for six columns has been latched.

  The latched discharge failure complement data from the discharge failure complement processing data / latch unit 82 is always output to the discharge failure complement processing calculation unit 84 regardless of the operation clock or the like. In the second embodiment, the latched discharge failure complement data has a bit width of 30 bits (corresponding to 6 columns × 5 pixels = 30 pixels).

  However, regarding the discharge failure complement priority data, as shown in FIG. 8, six data patterns are transferred from the discharge failure complement priority setting unit 55 for conversion of discharge failure nozzle discharge positions T1 to T4. ing. Therefore, it is necessary to select appropriately according to the position where the undischarge nozzle currently being converted should be printed. Therefore, since the discharge failure complement processing algorithm management unit 81 first performs processing for the position where the discharge failure nozzle at the position T1 should be printed, the discharge failure complement priority selection unit 83 instructs the discharge failure complement priority selection unit 83 to perform discharge failure complement priority. The signal is transferred so as to output the rank data.

  In this way, discharge failure complement data for six columns output from the discharge failure complement processing data latch unit 82 and discharge failure complement priority for T1 processing output from the discharge failure complement priority selection unit 83. The data is input to the discharge failure complement processing calculation unit 84.

  The function of the discharge failure complement processing calculation unit 84 is substantially the same as the function of the discharge failure complement algorithm execution unit 60 shown in the first embodiment.

  FIG. 9 is a diagram illustrating the function of the discharge failure complement processing calculation unit 84.

  The description content of FIG. 9 is substantially the same as the description content of FIG. The difference from the function of FIG. 4 shown in the first embodiment is that the conversion unit of discharge failure complement is 5 bits in the first embodiment, but 20 bits in the example shown in FIG. The other processes are the same.

  That is, the discharge failure complement position extraction unit 3-6-3-1 performs discharge failure complement based on discharge failure complement data and discharge failure complement priority data for discharge failure nozzle discharge position T1 processing. Determine possible positions. Then, the discharge failure complement priority determination unit determines the highest discharge failure complement priority from the positions where discharge failure complement is possible. Finally, the discharge failure complement data composition unit performs discharge failure complement based on the highest discharge failure complement priority position and discharge failure complement data from the possible discharge failure complement positions. That is, if there is print data at the position where the undischarge nozzle at the undischarge nozzle discharge position T1 should be printed, the print data is moved from the position where non-discharge complementation is possible to the highest discharge failure complement priority position. To do. On the other hand, if there is no print data at the position where the undischarge nozzle at the undischarge nozzle discharge position T1 is to be printed, the input print data is output as it is. Thus, discharge failure complement is performed.

  What is important here is that, as described in the first embodiment, the function of the discharge failure complement processing calculation unit 84 can be configured only by a combinational circuit. Therefore, when discharge failure complement data for 6 columns and discharge failure complement priority data for T1 processing are input, logically, there is print data at the discharge failure nozzle discharge position T1 at the same time. (Even if it is not present), non-discharge complemented data is output.

  However, in practice, a certain amount of gate delay is expected until an output is obtained from this input. Therefore, the discharge failure complement processing algorithm management unit 81 is input with an appropriate operation clock (approximately 2clk is sufficient). Wait until Thereafter, a signal is transferred to the discharge failure complement processing data / latch unit 82 so that the data output by the discharge failure complement processing calculation unit 84 is updated as discharge failure complement data for four new columns. In this way, the discharge failure complement processing data latch unit 82 that latches the discharge failure complement data for the new 6 columns for which discharge failure compensation relating to the print data at the discharge failure nozzle discharge position T1 has been performed is Then, the data is output again to the discharge failure complement processing calculation unit 84.

  Next, the discharge failure complement processing algorithm management unit 81 performs a discharge failure for T2 processing in the discharge failure complement priority selection unit 83 in order to process the position at which the discharge failure nozzle at the discharge failure nozzle discharge position T2 is to be printed. The signal is transferred so that the complementary priority data is output. In this manner, the discharge failure complement processing calculation unit 84 includes discharge failure complement data for 6 columns that have been subjected to discharge failure complement for the print dots at the discharge failure nozzle discharge position T1, and discharge failure nozzle discharge position T2. Undischarge complementation priority data for processing was input. Therefore, in accordance with the above procedure, discharge failure complement data for 6 columns that have been subjected to discharge failure compensation regarding print data at discharge failure nozzle discharge positions T1 and T2 is output after an appropriate gate delay.

  The discharge failure complement processing algorithm management unit 81 waits until an appropriate operation clock (approximately 2clk is sufficient) is input, and then the data output by the discharge failure complement processing calculation unit 84 It is updated as discharge failure complement data for 6 columns. In this manner, the signal is transferred to the discharge failure complement processing data latch unit 82. The discharge failure complement processing data / latch unit 82 that latches discharge failure complement data for six new columns that have been subjected to discharge failure compensation for the print data at the discharge failure nozzle discharge positions T1 and T2, The data is output again to the discharge complement processing calculation unit 84.

  Next, the discharge failure complement processing algorithm management unit 81 causes the discharge failure complement priority order selection unit 83 to perform discharge failure for T3 processing in order to process the position at which the discharge failure nozzle at the discharge failure nozzle discharge position T3 is to be printed. The signal is transferred so that the complementary priority data is output. In this way, the discharge failure complement processing calculation unit 84 includes discharge failure complement data for 6 columns that have been subjected to discharge failure complement for the print data of discharge failure nozzle discharge positions T1 and T2, and T3 processing. Undischarge complementation priority data for use was input. Therefore, according to the above procedure, discharge failure complement data for 6 columns, which has been subjected to discharge failure compensation regarding print data at discharge failure nozzle discharge positions T1 to T3, is output after an appropriate gate delay.

  The discharge failure complement processing algorithm management unit 81 waits until an appropriate operation clock (approximately 2clk is sufficient) is input, and thereafter, the data output by the discharge failure complement processing calculation unit 84 is newly set. Are updated as discharge failure complement data for 6 columns. In this way, the signal is transferred to the discharge failure complement processing data latch unit 82. In this way, the discharge failure complement processing data / latch unit 82 that latches discharge failure complement data for six new columns that have been subjected to discharge failure compensation for the printing dots at the discharge failure nozzle discharge positions T1 to T3, It is output again to the discharge failure complement processing calculation unit 84.

  Lastly, the discharge failure complement processing algorithm management unit 81 performs a process for the discharge failure nozzle discharge position T4 for the discharge failure nozzle to be printed. The signal is transferred so as to output the discharge complement priority data. In this manner, the discharge failure complement processing calculation unit 84 includes discharge failure complement data for 6 columns that have been subjected to discharge failure complement for the printing dots at the discharge failure nozzle discharge positions T1 to T3, and discharge failure complement for T4 processing. Priority data was entered. Thus, according to the above-described procedure, discharge failure complement data for 6 columns for which discharge failure complement for print dots at discharge failure nozzle discharge positions T1 to T4 has been performed is output after an appropriate gate delay.

  The discharge failure complement algorithm management unit 81 waits until an appropriate operation clock (approximately 2clk is sufficient) is input, and thereafter, the data output by the discharge failure complement processing calculation unit 84 is newly generated. It is updated as discharge failure complement data for 4 columns. In this way, the signal is transferred to the discharge failure complement processing data latch unit 82.

  In this manner, the discharge failure complement data / latch unit 82 latches discharge failure complement data for six new columns that have been subjected to discharge failure complement for the print data at the discharge failure nozzle discharge positions T1 to T4. . The discharge failure complement data / latch unit 82 transfers the data actually used for discharge failure complement to the discharge failure complement data S-RAM 56. That is, discharge failure complement data subjected to discharge failure complement for 4 columns is transferred to the discharge failure complement data S-RAM 56, and discharge failure complement processing for discharge failure complement for 4 columns is completed.

  In addition, even in the next four columns of non-discharge complementation, in order to repeat the same processing as described above, it is desirable that the column data of the non-discharge nozzle discharge position T4 be held. This is to enable the same processing as described above to be repeated only by extracting data for five columns after the next four columns. That is, the retained data becomes column data immediately before the next discharge failure complement target area.

[Effect of Example 2]
According to the second embodiment, the discharge failure nozzle 13 can be complemented. That is, in the second embodiment, when there is the discharge failure nozzle 13 in the print head 10 and there is data to be printed at that position, the complement target area is increased and complemented within an area of several columns. Further, the discharge failure complement priority can be set for each position where the discharge failure nozzles existing in each column should be printed, and the discharge failure complement priority changes every 4 columns. Therefore, the position of the nozzle having a high discharge failure complement priority also changes every four columns. That is, the principle of non-discharge complementation can be implemented without imposing a load on a specific nozzle.

  The undischarge complementing process has been described above for the first and second embodiments. There is no need to limit the number of nozzles or the number of columns.

  In addition, all the nozzle rows in the above embodiments have been described using nozzles that eject ink onto a recording medium. However, nozzles that do not eject ink onto a recording medium may be provided in the nozzle row. A nozzle that does not eject ink onto the recording medium is called a so-called dummy nozzle.

  In a recording head provided with such a nozzle row, for example, when a nozzle that ejects ink onto a recording medium is in a non-discharge state, it may be assigned to this dummy nozzle.

  For example, as an example of a mode in which dummy nozzles are provided at both ends of a nozzle row, a configuration in which three dummy nozzles are provided at both ends of a nozzle row (for example, 128 nozzles) configured of nozzles that eject ink onto a recording medium. is there.

  In other words, the above-described embodiment is a recording apparatus that uses an inkjet head having a nozzle row in which a plurality of nozzles for ejecting ink are arranged, and performs recording while scanning the inkjet head on a recording medium. Further, the embodiment includes an undischarge nozzle position storage unit that stores the position of an undischarge nozzle that cannot discharge ink among the plurality of nozzles arranged in the nozzle row. In the embodiment, the data allocation unit allocates the data to be ejected by the ejection failure nozzle to the normal nozzle according to the ejection failure complement priority and the position adjacent to the printing position of the ejection failure nozzle. Have The discharge failure complement priority is a print priority order for a plurality of normal nozzles located near the discharge failure nozzle in the nozzle row including the discharge failure nozzle instead of the discharge failure nozzle. The data allocating unit is a data allocating unit that allocates data to be ejected by the ejection failure nozzle every time a predetermined number of columns of column data along the scanning direction are created.

  In this case, the data allocating unit is a unit that executes a process of allocating data to be ejected by the non-ejection nozzle to other nozzles every time one column of data is created. The data allocating unit is a unit that executes a process of allocating data to be ejected by the non-ejection nozzle to other nozzles every time data of a plurality of columns is created. Further, the data allocating means is present in each column of the plurality of columns, and for each data to be ejected by the non-ejection nozzle, the data to be ejected by the non-ejection nozzle is normally In order to assign to nozzles, it is a means for setting discharge failure complement priority. Moreover, the inkjet head includes a plurality of the nozzle rows. Data for determining the discharge failure complement priority is stored so as to correspond to each of the plurality of nozzle rows, and the stored discharge failure complement priority is assigned to each nozzle row. ing.

  And the said Example can be grasped | ascertained as invention of a method. In other words, the above embodiment is a control method for a recording apparatus that uses an inkjet head including a nozzle row in which a plurality of nozzles for ejecting ink are arranged and performs recording while scanning the inkjet head on a recording medium. Further, the embodiment includes a non-discharge nozzle position storing step of storing, in a storage device, a position of a non-discharge nozzle that cannot discharge ink among the plurality of nozzles arranged in the nozzle row. . Further, the embodiment includes a data allocation step of assigning data to be discharged by the discharge failure nozzle to the normal nozzle according to discharge failure complement priority and adjacent positions. The discharge failure complement priority order is a discharge priority order for printing a plurality of normal nozzles located in the vicinity of the discharge failure nozzle instead of the discharge failure nozzle in the nozzle row including the discharge failure nozzle. Complementary priority. The adjacent position is a position where the normal nozzle prints and is a position adjacent to the position where the undischarge nozzle prints. The data assigning step is a data assigning step for assigning data to be ejected by the discharge failure nozzle every time a predetermined number of columns of column data along the scanning direction are created.

  In the above-described embodiment, the nozzles are located further outside the nozzles located at both ends of the nozzle row and are not used in a normal printing operation. Further, in the above embodiment, if at least one of the nozzles located at both ends of the nozzle row is an undischargeable nozzle that cannot perform printing, a nozzle that is not used in the normal printing operation is used. The recording apparatus has a control means for controlling as described above.

  In this case, the nozzles that are not used in the normal printing operation are nozzles that are used to correct the mechanical position of the inkjet head. Furthermore, the nozzles that are not used in the normal printing operation are nozzles that perform pseudo heat treatment that is not directly related to the printing operation.

This recording apparatus can be grasped as a method invention. In other words, the above-described embodiment is a method for controlling a recording apparatus that uses an inkjet head having a nozzle row in which a plurality of nozzles that eject ink are arranged, and performs recording while scanning the inkjet head with respect to a recording medium. is there. Furthermore, the above-described embodiment includes a nozzle installation step of providing nozzles that are located further outside the nozzles located at both ends of the nozzle row and are not used in a normal printing operation. Further, in the above embodiment, if at least one of the nozzles located at both ends of the nozzle row is an undischargeable nozzle that cannot perform printing, a nozzle that is not used in the normal printing operation is used. And a control process for controlling as described above.

FIG. 5 is a diagram simply illustrating a printing state when there is nozzle discharge failure in the recording apparatus PR1 that is Embodiment 1 of the present invention. It is a figure which shows the principle of undischarge complementation in Example 1 of this invention most simply. It is a figure which shows the internal structure of ASIC3, and the outline of the data flow. It is the figure which portrayed the mechanism of the undischarge complementation algorithm execution part 60 in more detail. In Example 1, it is a figure which shows the structure of the data generation part after undischarge complementation which is an element in an undischarge complementation system. In Example 2 of this invention, it is a figure which shows simply the mode of printing when there exists a nozzle discharge failure. In Example 2 of this invention, it is a figure which shows the principle of discharge failure complement most simply. In Example 2, it is a figure which shows each element, and is a figure which shows the data flow between them. In Example 2, it is explanatory drawing of a discharge failure complement process calculating part.

Explanation of symbols

PR1 ... Recording device,
3 ... ASIC,
PC ... personal computer,
10 ... print head,
34 ... CPU,
35 ... SD-RAM,
44: Print data generation unit,
46: Print data reading section,
48: Print timing generation unit,
50: Undischarge complementing block,
51. Undischarge information storage unit,
52 ... Undischarge complementation data extraction timing generation unit,
53. Undischarge complementing data extraction unit,
55... Discharge failure complement priority setting unit,
56 ... S-RAM for discharge failure complement data,
57... Discharge failure complement data reading unit,
58... Data generation unit after non-discharge complementation,
60: Undischarge complementing algorithm execution unit,
61 ... Extraction unit of non-discharge complementable position,
62... Priority determination unit,
63: Undischarge complementation data synthesis unit.

Claims (10)

In a recording apparatus that uses an inkjet head having a nozzle row in which a plurality of nozzles that eject ink are arranged, and that records while scanning the inkjet head on a recording medium,
Undischarge nozzle position storage means for storing the position of an undischarge nozzle that cannot discharge ink among the plurality of nozzles arranged in the nozzle row;
For a plurality of normal nozzles located in the vicinity of the non-discharge nozzle in the nozzle row including the non-discharge nozzle, the non-discharge complement priority is a priority for printing instead of the non-discharge nozzle, and the normal nozzle prints A data allocating means for allocating data to be discharged by the discharge failure nozzle to the normal nozzle according to a position adjacent to the printing position of the discharge failure nozzle. Data allocating means for allocating data to be ejected by the discharge failure nozzle every time a predetermined number of columns of column data are created;
A recording apparatus comprising: In claim 1,
The recording apparatus according to claim 1, wherein the data allocating unit is a unit that executes a process of allocating data to be ejected by the non-ejection nozzle to another nozzle every time one column of data is created. In claim 1,
The recording apparatus according to claim 1, wherein the data allocating unit is a unit that executes a process of allocating data to be ejected from the non-ejection nozzle to another nozzle every time data of a plurality of columns is created. In claim 3,
The data allocating means is data existing in each column of the plurality of columns, and for each data to be discharged to the discharge failure nozzle, the data to be discharged to the discharge failure nozzle is set in the vicinity of the discharge failure nozzle. A recording apparatus, characterized in that it is means for setting a discharge failure complement priority in order to assign to normal nozzles. In any one of Claims 1-4,
The inkjet head includes a plurality of the nozzle rows,
Data for determining the discharge failure complement priority is stored so as to correspond to each of the plurality of nozzle rows, and the stored discharge failure complement priority is assigned to each nozzle row. A recording apparatus. In a control method of a recording apparatus that uses an inkjet head having a nozzle row in which a plurality of nozzles that eject ink are arranged, and that records while scanning the inkjet head on a recording medium,
An undischarge nozzle position storage step of storing, in a storage device, the position of an undischarge nozzle that cannot discharge ink among the plurality of nozzles arranged in the nozzle row;
For a plurality of normal nozzles located in the vicinity of the non-discharge nozzle in the nozzle row including the non-discharge nozzle, the non-discharge complement priority is a priority for printing instead of the non-discharge nozzle, and the normal nozzle prints A data allocation step of assigning data to be discharged by the discharge failure nozzle to the normal nozzle in accordance with a position adjacent to the printing position of the discharge failure nozzle, the scanning direction A data allocating step of assigning data to be discharged by the discharge failure nozzle every time a predetermined number of columns of column data are created;
A control method for a recording apparatus, comprising: In a recording apparatus that uses an inkjet head having a nozzle row in which a plurality of nozzles that eject ink are arranged, and that records while scanning the inkjet head with respect to a recording medium,
Nozzles located further outside the nozzles located at both ends of the nozzle row and not used in a normal printing operation;
If at least one of the nozzles located at both ends of the nozzle row is an undischargeable nozzle that cannot be printed, the nozzle is not used in the normal printing operation. Control means for performing non-discharge nozzle complement processing;
A recording apparatus comprising: In claim 7,
The recording apparatus, wherein the nozzle that is not used in the normal printing operation is a nozzle that is used to correct a mechanical position of the inkjet head. In claim 7,
The recording apparatus, wherein the nozzle that is not used in the normal printing operation is a nozzle that performs a pseudo heat treatment not directly related to the printing operation. In a control method for a recording apparatus, which uses an inkjet head having a nozzle row in which a plurality of nozzles that eject ink are arranged, and records the ink jet head while scanning the recording medium,
A nozzle installation step of providing nozzles located further outside the nozzles located at both ends of the nozzle row and not used in a normal printing operation;
If at least one of the nozzles located at both ends of the nozzle row is an undischargeable nozzle that cannot be printed, by controlling to use a nozzle that is not used in the normal printing operation, A control process for performing the non-discharge nozzle complement process;
A control method for a recording apparatus, comprising:

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