JP2007160802A - Ink-jet recorder and recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recorder complementing a failure of delivery without reducing throughput sharply and applying a big load to part of recording elements of a recording head, and a recording method. <P>SOLUTION: By detecting the position of a delivery failure nozzle 69, the delivery failure complementing method with a multipass manner is switched to the non-delivery failure complementing method according to the detected position of the delivery failure nozzle 69. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus that performs recording by discharging a liquid onto a recording medium, and more particularly to an ink jet recording apparatus having a function of detecting non-ejection and complementing non-ejection.

  2. Description of the Related Art In recent years, with the spread of the Internet, recording devices such as printers, copiers, and facsimiles are widely used in offices and general homes connected to electronic devices such as computers and workstations. As a recording method in such a recording apparatus, an electrophotographic method, an ink jet method, a thermal method and the like are generally spread. In particular, the inkjet recording method is widely used as a recording method for recording apparatuses, not only for general home use but also for business use, because it can record on various recording media. However, since the ink jet recording method performs recording by ejecting liquid from a minute nozzle, if thickened ink or the like accumulates in the nozzle, ejection failure (hereinafter also referred to as non-ejection) occurs, resulting in high image quality. Recording results may not be obtained. Further, as a cause of ejection failure other than the above, ejection failure due to disconnection of an electric circuit related to ejection may be considered. As described above, since normal recording cannot be performed in a state where there are defective nozzles, various methods for detecting non-discharge nozzles have been proposed.

  For detection of non-ejection nozzles, methods such as an optical method, an electrostatic method, an acoustic method (vibration detection method), and a scanner method have been proposed. As for the timing for detecting the non-ejection nozzles, there are a method for detecting when the power is turned on, a method for detecting when a predetermined amount of ejection is completed, a method for detecting at the start of recording, a method for selectively detecting by the user, and these methods. A method of detecting in combination has been proposed. For the purpose of detecting non-ejection due to circuit disconnection, a method of detecting when a predetermined amount of ejection is completed is often used.

  When a non-ejection nozzle is detected, non-ejection complementation (hereinafter also simply referred to as complementation) is performed in such a manner as to supplement the recording of a portion where other nozzles could not perform the ejection due to non-ejection. As for the nozzle complementing method, conventionally, the auxiliary nozzle is supplemented by sub-scanning (Patent Document 1), and the non-ejection nozzle data is distributed and complemented to the adjacent nozzles of the non-ejection nozzle (Patent Document 2). There are some that perform non-ejection complementation during multiple scanning (Patent Documents 3 and 4). Moreover, what performs non-discharge complementation by shifting an in-line head (patent document 5) can also be used.

  FIG. 1 is a diagram illustrating a complementing method in the case of performing non-ejection complementing using a multi-pass method in the prior art. The recording head 11 performs recording by ejecting ink while moving in the main scanning direction of the arrow S. The recording images C and D on the recording medium are a set of dots formed by the recording head 11 scanning and ejecting ink. In this figure, for ease of explanation, the recording images C and D of the recording medium that is originally moved are fixed, and the recording head 11 is shown to have moved in the originally fixed direction. Further, this figure shows a multi-pass method, and shows a method of performing printing in two passes in which printing for one line is performed by two scans.

  The recorded image C is a recorded image recorded by the first scan (hereinafter also referred to as a first scan), and the recorded images C are recorded in a staggered pattern by the recording pixels 13. Further, in the recorded image C, white spots 16 that are non-recording portions that are not recorded by the non-ejection nozzles 12 occur. The recorded image D is a result of recording in the second scan (hereinafter also referred to as second scan), and is recorded so as to compensate for the gap between the recording portions of the recorded image C. As can be seen from the partial enlarged view E of the recorded image D, the white spot 16 portion that has occurred in the first scan is complemented by the complement nozzle 17 in the second scan.

  In this way, recording is performed in the previous scan, and the portion that has not been recorded by the non-ejection nozzle is complemented by the complementary nozzle in the subsequent scan. At this time, since the complementary nozzle performs complementation in addition to the original recording, recording is performed at an ejection frequency twice that of the other nozzles.

JP-A-9-174824 JP 2001-146004 A JP 2000-255044 A Japanese Patent Laid-Open No. 2000-263772 Japanese Patent Laid-Open No. 10-6488

  As in Patent Documents 1, 3 and 4, when non-ejection complement is performed by a multi-pass method in which printing for one line is performed by a plurality of scans, a portion that has not been recorded by non-ejection in the previous scanning is later Recording is performed by scanning. For example, in the case of a two-pass image recording method in which recording for one line is performed by two scans, it is complemented by discharging in the second scan to the recording portion of the nozzle that was not ejected in the first scan. can do. Although this method can perform reliable complementation, this method requires a plurality of scans, so that the printing speed is reduced and the throughput is reduced as compared with the case of printing in one pass. There's a problem.

  In addition, when supplementation is performed using adjacent nozzles as described in Patent Documents 2 and 5, since the ejection frequency of the adjacent nozzles that complement non-ejection nozzles is increased and the load on the printing element is increased, compensation is performed. It is conceivable that the life of the nozzle being performed is shortened.

  As described above, the conventional technique has not proposed non-ejection complementation in which printing and complementation are performed in one pass and the load on the nozzle does not increase without affecting the throughput.

  Accordingly, an object of the present invention is to provide an ink jet recording apparatus and a recording method capable of performing non-ejection complementation without significantly reducing the throughput and without applying a large load to some recording elements of the recording head. To do.

  Therefore, the ink jet recording apparatus of the present invention includes a carriage on which a recording head including a plurality of nozzles for ejecting ink is mounted, a moving unit that reciprocates the carriage in the main scanning direction, and a direction that intersects the moving direction of the carriage. Conveying means for conveying the recording medium to the recording medium; detecting means for detecting the presence and position of a non-ejection nozzle that does not eject ink at the plurality of nozzles; and detecting the non-ejection nozzle when the detection means detects that there is a non-ejection nozzle. Recording is performed in the first scan of the head, the recording medium is transported in an amount corresponding to the position of the non-ejection nozzle, and the non-ejection nozzle does not record in the first scan. And a recording control means for performing recording in the second scanning of the recording head, corresponding to nozzles other than the discharge nozzles.

  The recording method of the present invention includes a carriage on which a recording head having a plurality of nozzles for ejecting ink is mounted, a moving step for reciprocating the carriage in the main scanning direction, and a direction intersecting the moving direction of the carriage. A recording step of conveying a recording medium, a detection step of detecting the presence and position of a non-ejection nozzle that does not eject ink at the plurality of nozzles, and the recording head when the detection means detects the presence of a non-ejection nozzle Recording is performed in the first scan, and the recording medium is transported in an amount corresponding to the position of the non-ejection nozzle, and the non-ejection is performed on a portion not recorded by the non-ejection nozzle in the first scan. And a recording control step in which nozzles other than the nozzles are made to correspond and recording is performed in the second scanning of the recording head.

  According to the ink jet recording apparatus and the recording method of the present invention, it is possible to perform non-ejection complementing with little influence on the throughput. In the case where there is a non-ejection nozzle within a quarter of the entire nozzle including the nozzle at the end of the recording head with respect to the recording medium conveyance direction, the non-ejection nozzle does not print in the first scan. This is because at least the foremost nozzle of the print head is complemented in the second scan.

Hereinafter, the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 2 is a perspective view showing a configuration of an inkjet recording apparatus M according to an embodiment of the present invention. The recording apparatus M is a serial scanning recording apparatus, and the recording head 112 repeats the operations of the sub-scanning in the arrow Y direction for conveying the recording medium and the main scanning moving in the arrow X direction orthogonal to the arrow Y direction alternately. Recording is performed by ejecting ink onto the recording medium (see FIG. 11). First, the driving force of the paper feed motor 5 is transmitted to the paper feed roller 6 through a gear, and the recording medium placed on the transport tray T is fed into the recording apparatus M. The fed recording medium is guided to a recording portion through a sheet feeding roller 6 and a pressure roller (not shown).

  The recording head 112 is mounted on the carriage unit 2. The carriage unit 2 is slidably supported by a guide rail (not shown), and is driven along a guide rail (not shown) by driving means including the carriage motor 3 and the like. Reciprocal movement in the scanning direction is possible. In this embodiment, the carriage belt 4 is used to transmit the driving force from the carriage motor 3 to the carriage unit 2, but other driving transmission methods such as a lead screw may be used instead of the carriage belt.

  FIG. 3 is a diagram showing a configuration of ink supply in the recording apparatus M of FIG. In the recording apparatus, an ink flow path is formed by a tube 45 and a head joint 46 for supplying ink from the ink tank 39 to the recording head 112. Ink is supplied from the ink tank 39 and sent to the recording head 112 via the tube 45 and the joint 46. The ink buffer 41 has a function of temporarily holding ink that overflows from the tank mainly due to the expansion of air in the tank in the supply path. The ink tank 39 is molded by injection blow or the like using a resin such as PP or PE, and is assembled using techniques such as ultrasonic welding, thermal welding, adhesion, and fitting. The inside of the ink tank 39 has a type in which the exterior functions as an ink chamber as it is, a type having an ink bag filled with ink inside, or a type in which a porous body is inserted to hold ink and simultaneously generate negative pressure Etc. When the tank is provided with a negative pressure mechanism, a negative pressure may be generated by supporting the bag portion inside the tank in the expansion direction by a spring mechanism or the like provided inside or outside the bag.

  The recording apparatus of the present embodiment is provided with a recording head recovery mechanism for always maintaining the state of the nozzles that eject ink of the recording head 112 in an optimum state. This recovery mechanism includes a cap function that prevents ink from evaporating from the nozzles and eliminates thickened ink in the nozzles by negative pressure, and paper dust and dirt adhering to the surface of the recording head 112 where the nozzles are formed. There is a wiper function to wipe off.

  Normally, when the recording apparatus is in a resting state, a cap (not shown) that is a part of the recovery mechanism is attached to the nozzle forming surface of the recording head 112. For this reason, at the start of the recording operation, the cap is first removed to enable the carriage unit 2 to scan, and in the case of a serial scan type recording apparatus, the carriage unit 2 can be scanned in the main operation direction.

  In the case of such serial scan recording, the recording medium may be transported after a plurality of scans without transporting the recording medium in one scanning as required. In addition, a recording method has been realized in which an area recorded by one scan is recorded by n scans, and the recording medium is conveyed by 1 / n of the conveyance amount at a time.

  FIG. 4 is a diagram showing an example of a wiper used for the wiper function of the recording apparatus M in FIG. The wiper is attached to a wiper holder 27 (not shown) using a wiper fixing bracket (not shown). The wiper is positioned in a hole (not shown) opened in the wipers 21 and 22 and a wiper holder (not shown). This is done by fitting with the pin. The wipers 21 and 22 perform the wiping operation by moving in the W direction shown in FIG. 4 and wipe the nozzle forming surface. When the wiping operation is completed, the carriage unit 2 is retracted out of the wiping area, drives the wipers 21 and 22 in the reverse direction, returns to the position where the wiping is started, and waits until the next wiping operation starts.

  FIG. 5 is a perspective view showing the recording head 112 (see FIG. 11) of the recording apparatus M of FIG. In the case of black ink, the recording head 112 has 640 nozzles arranged at a nozzle density of about 245 per cm. In the case of color ink, each color has 1280 nozzles at a density of about 490 nozzles per cm. It is arranged.

  The ink used in the recording apparatus M of the present invention is a water-soluble organic solvent, and can be generally used as long as it is used in a conventionally known ink. Specifically, alkyl having 1 to 5 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, and n-pentanol. Alcohols; Amides such as dimethylformamide and dimethylacetamide; Ketones or ketoalcohols such as acetone and diacetone alcohol; Ethers such as tetrahydrofuran and dioxane; Diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene Oxyethylene or oxypropylene addition polymers such as glycol, polyethylene glycol, polypropylene glycol; ethylene glycol, propylene group Alkylene glycols in which the alkylene group contains 2 to 6 carbon atoms, such as coal, trimethylene glycol, butylene glycol, 1,2,6-hexanetriol, hexylene glycol; thiodiglycol; glycerin; ethylene glycol monomethyl (or Lower alkyl ethers of polyhydric alcohols such as ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl) ether; triethylene glycol dimethyl (or ethyl) ether, tetraethylene glycol dimethyl (or ethyl) Lower dialkyl ethers of polyhydric alcohols such as ether; sulfolane, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. The content of the water-soluble organic solvent as described above is generally in the range of 1 to 49%, preferably 2 to 30% by weight with respect to the total weight of the ink. The water-soluble organic solvents as described above can be used alone or as a mixture, but the most preferable liquid-medium composition in the case of having a medium is at least one water-soluble high-boiling organic solvent such as diethylene glycol, triethylene glycol, glycerin. Containing polyhydric alcohols. If necessary, metal salts such as magnesium nitrate, calcium nitrate, and barium nitrate may be used to improve printing quality.

  FIG. 6 shows a control unit of the recording apparatus M of the present embodiment. Reference numeral 101 in the figure denotes a programmable peripheral interface (hereinafter referred to as PPI), which receives a command signal (command) and a recording information signal sent from a host computer (not shown) and transfers them to the MPU 102. In addition to the transfer, a signal from the home position sensor 107 for detecting the control of the console 106 and the carriage being at the home position is input. An MPU (microprocessing unit) 102 controls each part in the ink jet printer apparatus according to a control program stored in the control ROM 105. The RAM 103 stores received signals or is used as a work area for the MPU 102 and temporarily stores various data. The font generation ROM 104 stores pattern information such as characters and records corresponding to the code information, and outputs various pattern information corresponding to the input code information. The print buffer 121 is a buffer for storing data developed by the ROM 104 or the like, and has a capacity for m rows of data to be recorded. The control ROM 105 is a control ROM in which processing procedures executed by the MPU 2 are stored. These units are controlled by the MPU 102 via the address bus 117 and the data bus 118, respectively.

  The carriage motor 3 performs reciprocal scanning by moving a carriage on which the recording head 112 is mounted. The capping motor 113 blocks the ink nozzle from the outside air by its power, and abuts the cap for preventing the nozzle from drying on the recording head 112. The motor driver 115 drives the carriage motor 108, the motor driver 116 drives the paper feed motor 110, and the motor driver 114 drives the capping motor 113. The home position sensor 107 is provided in the vicinity of the home position of the carriage and detects that the carriage on which the recording head 112 is mounted has reached the home position. A sheet sensor 109 detects the presence or absence of a recording medium such as recording paper, that is, whether or not the recording medium is supplied. The recording head 112 is an ink jet recording head that uses thermal energy to cause ink to change state due to film boiling and eject ink droplets. The recording head 112 is provided with m (for example, m = 64) nozzles (not shown) and m ejection heaters (not shown) corresponding to the nozzles. The head driver 111 is a driver for driving the ejection heater of the recording head 112 in accordance with the recording information signal. The power supply unit 120 is a power supply unit that supplies power to the above-described units, and includes an AC adapter and a battery as a drive power supply device.

  In the above configuration, the MPU 102 is connected to a host device such as a computer via the PPI 101. The MPU 102 controls the recording operation based on the command and recording information signal sent from the host device, the processing procedure of the program stored in the control ROM 106, and the recording information stored in the RAM 106.

  In the recording apparatus M of the present invention, recording data is transmitted from a host 100 that transmits recording data via a parallel port, an infrared port, a network, or the like. At that time, a command describing the type of media to be recorded, the media size, the recording quality, the paper feeding method, and whether or not to automatically determine the object is transmitted to the head portion of the data. The media types are media such as plain paper, OHP, and glossy paper, and special media types such as transfer film, cardboard, and banner paper. The media size is A4, A4 letter, A3, B4, B5, envelope, postcard or the like. The recording quality includes draft, high quality, medium quality, specific color enhancement, monochrome / color type, and the like. The paper feeding method includes ASF, manual feed, cassette 1, cassette 2, and the like. The main unit accepts data containing this information, and based on various data stored in a memory area (not shown), usually called a ROM, the number of recording passes during multi-pass printing and ink ejection per unit area Determine the amount, recording direction, etc. and perform recording. In some cases, information such as whether or not to apply the treatment liquid is transmitted as a command. In accordance with these pieces of information, the recording apparatus reads data necessary for recording from the ROM described above and performs recording according to those data. However, in addition to the above, the data read from the ROM includes the mask type used when printing each pass, the recording head drive conditions (for example, the applied pulse shape and application time), the droplet size, and the paper feed conditions. And carriage speed.

7, 8, and 9 show the flow of processing during recording by the recording apparatus M according to the present embodiment.
In S23 of FIG. 7, when recording is completed in a recording sequence to be described later, it is confirmed in S24 whether the recording dot number N exceeds the prescribed dot number N1 (threshold). If the number of recording dots exceeds N1, the wiping operation is performed in S25, and if not, it is further confirmed in S26 whether the recording of one page is completed. When the recording is continued, the process returns to S23 and the recording sequence is performed again. If the recording of one page is completed, it is confirmed in S27 whether there is recording data for the next page. If there is, the process returns to S23 to perform recording, and if not, waits for 55 seconds until capping. When 55 seconds have elapsed, wiping is performed in S25, and then capping is performed in S21 to complete recording.

  Here, the recording sequence in S23 will be described with reference to FIG. First, when this sequence starts, it is confirmed in S9 whether the recording head 112 is capped. If it is in a capped state, the cap is removed in S10. If it is not capped, the process proceeds to S11 to perform a pre-recording recovery sequence to be described later. When the pre-recording recovery sequence ends, the recording medium on the transport tray is fed into the recording apparatus M in S12. Thereafter, in S13, it is confirmed whether or not there is data for one scan in the print buffer 121. If there is data, preliminary ejection before the start of recording is performed in S14, and recording is performed in S15 after the end. If there is no data in the print buffer 121 in S13, the process waits in S17 until the data is ready. If the recording data is not complete, the process waits for a predetermined time (Tcap) in S18. If the recording data is still not complete, the capping is performed in S19, and further waiting for the data to be completed. However, if the preset time Tpreinj is exceeded within a certain time in the cap open state, preliminary ejection is performed in S21 to prevent ejection failure at each set time. When the recording data for one scan is completed during the recording weight and recording is possible, preliminary ejection is performed immediately before recording in S14, and the recording operation is performed in S15.

  In the present embodiment, preliminary ejection is performed every time before scanning, but it is also possible to determine a predetermined time and select whether or not to perform preliminary ejection with a timer. When the recording medium is discharged in S16 after the recording in S15 is completed, the recording is discharged in S22 and the recording sequence is completed.

Here, the recovery sequence before recording in S11 will be described with reference to FIG.
A recording start signal is received at S1, the current time (Ta) is read at S2, and the previous cleaning time (Tb) is read at S3. A clean interval time (T) is calculated in S4 based on the time information read in S2 and S3. In S5, it is determined whether the cleaning interval time calculated in S4 exceeds the specified time U. If the specified time U is exceeded, cleaning is executed in S6. Thereafter, in S7, the cleaning timer is reset to enter the READY state in S8. If the cleaning interval time (T) does not exceed the specified time (U) in S5, the REDY state of S8 is entered directly from S5.

Various methods have been proposed for detecting non-ejection of ink from the nozzles, but the optical non-ejection detection method is used in the recording apparatus M of the present embodiment.
FIGS. 10A to 10C are diagrams illustrating an optical non-ejection detection method in the recording apparatus M of the present embodiment. The light emitted from the light emitting element 58 in the drawing is incident on the light receiving element 59 arranged to face the light emitting element 58. The light receiving element 59 generates a current corresponding to the amount of light received, and is arranged so that the amount of light received from the light emitting element 58 can be detected. Further, the light emitting element 58 and the light receiving element 59 are arranged so that the optical axis 60 of the light emitted from the light emitting element 58 is parallel to the arrangement of the nozzles of the recording head 112. In addition to such a configuration, the light emitting element 58 and the light receiving element 59 are arranged so that the optical axis is inclined with respect to the nozzle row, and the non-ejection nozzle is detected while the recording head 112 is moved. It is not contrary to the purpose of the form.

  In the state where ink is not ejected from the recording head 112 as shown in FIG. 10A, the light receiving element 59 always receives the light emitted from the light emitting element 58 because there is nothing to block the light emitted from the light emitting element 58. ing. On the other hand, when ink is ejected from the recording head 112 as shown in FIG. 10B, since the ink passes on the optical axis 60, the light is blocked and the amount of light received by the light receiving element 59 is reduced. As the amount of received light decreases, the signal level from the light receiving element 59 decreases. By checking the signal level of the light receiving element 59 in this way, it is possible to detect the presence or absence of ink ejection from each nozzle, and thereby the recording apparatus M knows the presence or absence of a non-ejection nozzle and the position of the non-ejection nozzle. Can do. Such non-ejection nozzle detection is performed in advance for each nozzle before the start of recording. Thereby, the recording apparatus M can know the presence / absence of the non-ejection nozzle and the position of the non-ejection nozzle before starting the recording. The ink 61 ejected for detecting the non-ejection nozzle enters the ink receivers 62 and 63 as the waste ink 65 and is discharged from the ink discharge port 64 and is guided and absorbed on a waste ink absorber 66 (not shown). If it is structurally difficult to absorb the ink discharged to the absorbing means such as the waste ink absorber 66, the ink may be collected in an ink reservoir or container having an appropriate volume.

  FIG. 11 is a diagram illustrating a non-ejection nozzle complementing method (hereinafter also referred to as an end non-ejection complementing method) according to an embodiment of the present invention. The recording head 112 performs recording by ejecting ink while moving in the arrow S direction. The recording images F and G on the recording medium are a set of dots formed by the recording head 112 moving and ejecting ink. In this figure, for ease of explanation, the recording medium that is moved by conveyance is fixed, and the originally fixed recording head 112 is moved in the direction opposite to the conveyance direction of the recording medium. A recording image F in the figure is a set of recording pixels of recording performed by the recording head 112 in one scan (hereinafter also referred to as first scanning), and a non-ejection nozzle 69 is provided below the recording image F. There is a white spot 70 which is a portion where recording was not performed. In order to complement the white spot portion 70, it is determined from the position of the non-ejection nozzle 69 which column the white spot position 70 is generated from the end recording pixel row 81 of the recorded image F. Then, in the next scanning (hereinafter also referred to as the second scanning), the recording medium is transported by a minimum amount so that recording can be performed on the white spot 70 (the recording head 112 is moved in the drawing). That is, the recording medium is transported so that the nozzle 77 at the end corresponds to the position where the white spot 70 is generated. As a result, the printable area of the print head 112 overlaps between the first scan and the second scan from the row of white spots 70 to the end print image element row 81. In this case, the nozzle 77 at the end of the recording head 112 is always a complementary nozzle. Note that the nozzle 77 at the endmost portion does not necessarily correspond to the blank portion 70, and for example, the nozzle adjacent to the nozzle 77 may correspond by further overlapping one nozzle. For the overlapping portion, recording is performed in the second scan only in the portion where recording is not performed by the non-ejection nozzle 69. When there are a plurality of non-ejection nozzles, the complementary nozzle 77 at the end of the recording head 112 performs recording in the subsequent scanning at the whiteout portion that is farthest from the end recording image element array 81. The recording head 112 is moved to perform.

  In the embodiment of the present invention, the non-ejection supplement described above with reference to FIG. 11 is performed according to the position of the non-ejection nozzle. As a result, a reduction in throughput can be prevented as compared with the conventional complementing method using multi-pass recording (FIG. 1).

  That is, in the case of the end non-ejection complementing method, the effect of maintaining the speed is small unless the non-ejection nozzle is located at a position closer to the outermost end nozzle 82 than the half position of all nozzles from the outermost end nozzle 82. That is obvious. Even if there are a plurality of non-ejection nozzles, if the non-ejection nozzles that are farthest from the outermost nozzle 82 are not closer to the outermost nozzle 82 than the half of all nozzles, the advantage in throughput There is no sex. Thus, the effect of maintaining the speed varies depending on the position of the undischarge nozzle in the whole nozzle. If there is a non-ejection nozzle at a position 1/3 of all nozzles away from the endmost nozzle 82, the number of effective recording nozzles is 2/3 of the total number of nozzles, and similarly 1/3 from the endmost nozzle 82. When the position is 4 away, the number of effective recording nozzles is 3/4 of the total number of nozzles. Therefore, when this embodiment is applied, from the viewpoint of maintaining speed, there is a case where the non-ejection nozzle is located at a position closer to the endmost nozzle 82 than 1/4 from the endmost nozzle 82 with respect to all the nozzles. It is desirable to adapt to.

  When there is no non-ejection nozzle at a position closer to the endmost nozzle than 1/4 from the endmost nozzle 82, there is no avoiding means for speed reduction. Switching to a two-pass complementing method is superior in terms of image quality. Therefore, in such a case, the discharge failure complement method using the multi-spath method which is a conventional technique is adopted.

  FIG. 12 shows a determination sequence as to which of the present embodiment and the prior art is employed. When there is a nozzle that is determined to be non-ejection in the non-ejection detection of S29, the position of the non-ejection nozzle that is farthest from the endmost nozzle 82 in S30 is from the endmost nozzle 82 with respect to all the nozzles. Determine if the position is within 1/4. When the position is within 1/4, a sequence for complementing by the end non-ejection complementing method is performed. Further, when it is determined in S30 that the position of the non-ejection nozzle is not within a quarter of the end nozzle 82 with respect to all the nozzles, in S32, it becomes a complementary method of the conventional multi-pass method, A conventional non-ejection complementing sequence is performed. If it is determined in S30 that the position of the non-ejection nozzle is within a quarter of the end nozzle 82 with respect to all the nozzles, supplementation by end non-ejection complementation is performed in S31.

  In this way, when the complementing method is switched depending on the position of the non-ejection nozzle and the position of the non-ejection nozzle is within a quarter of the end nozzle 82 with respect to all the nozzles, the complementing method of the present embodiment By doing this, non-ejection supplementation could be performed without significantly reducing the throughput.

(Second Embodiment)
This embodiment is substantially the same as the first embodiment, but differs from the first embodiment in that the nozzle that complements the non-ejection nozzle is changed. In other words, in the second scan, the nozzle that does not complement the portion that overlaps the portion recorded in the first scan becomes a nozzle that does not discharge. On the other hand, the nozzle which is complementing is always discharging, and the balance becomes worse from the viewpoint of the life of the nozzle. Therefore, it is possible to avoid a problem that the load is concentrated on a specific nozzle by changing the nozzle to be complemented in a predetermined recording unit. As the predetermined recording unit, a scanning unit, a page unit, a recording operation unit, a predetermined recording dot unit, or the like can be used. In the present embodiment, a method of switching the complementary nozzle for each scanning unit is adopted.

  FIG. 13 shows a sequence obtained by adding the method of changing the nozzle of the present embodiment to the sequence of FIG. Steps up to S31 are the same as those in FIG. 12, and a description thereof is omitted here. In S33, it is determined whether or not it is time to change the nozzle to be complemented, that is, whether or not it is a predetermined recording unit break. If it is a predetermined recording unit break, the complementary nozzle is changed and complementing (recording) is started. If it is not a predetermined recording unit break, complement (record) is performed without changing the complement nozzle.

  14 (a) to 14 (c) and FIG. 15 are diagrams showing a method of changing a complementary nozzle for complementing the white spot 70 in FIG. Recording is performed by changing the overlap amount for each scan as shown in FIGS. 14A to 14C and changing the complementary nozzle for each scan as shown in FIG. How to overlap is related to the number of non-ejecting nozzles and the position of non-ejecting nozzles, and therefore cannot be determined in general. However, considering the discharge balance of the nozzles, it is preferable to reduce the number of nozzles that do not discharge as much as possible. In addition, it is fully conceivable that there are nozzles that do not discharge even when such a method is used. In that case, it is possible to balance the discharge with other nozzles by increasing the number of nozzles that do not discharge during preliminary discharge.

  By doing in this way, the fixed nozzle can always become a complementary nozzle, and the malfunction that the discharge balance with the nozzle which does not discharge becomes bad can be avoided.

It is the figure which showed the non-discharge complementation method of the prior art. It is a perspective view which shows the inkjet recording device of this invention. FIG. 3 is a diagram illustrating a configuration of ink supply in the recording apparatus of FIG. 2. FIG. 3 is a diagram illustrating an example of a wiper of the recording apparatus in FIG. 2. FIG. 3 is a perspective view showing a recording head of the recording apparatus of FIG. 2. 2 shows a control unit of the recording apparatus of the present embodiment. 2 shows a flow of processing at the time of recording in the recording apparatus according to the present embodiment. 2 shows a flow of processing at the time of recording in the recording apparatus according to the present embodiment. 2 shows a flow of processing at the time of recording in the recording apparatus according to the present embodiment. (A) to (c) are diagrams illustrating an optical non-ejection detection method in the recording apparatus of the present embodiment. It is the figure which showed the complementary method of the non-ejection nozzle in embodiment of this invention. The judgment sequence which employ | adopts the complement method of an edge part non-ejection complement and a prior art is shown. 13 shows a sequence obtained by adding a sequence for changing complementary nozzles to the sequence of FIG. (A)-(c) is the figure which showed the method of changing the complementary nozzle of this embodiment. It is the figure which showed the method of changing the complementary nozzle of this embodiment.

Explanation of symbols

3 Carriage Motor 58 Light Emitting Element 59 Light Receiving Element 60 Optical Axis 69 Non-ejecting Nozzle 70 White Hole 77 Complementary Nozzle 82 Endmost Nozzle 112 Recording Head M Recording Device

Claims (5)

A carriage equipped with a recording head having a plurality of nozzles for discharging ink;
Moving means for reciprocating the carriage in the main scanning direction;
Conveying means for conveying a recording medium in a direction intersecting with the moving direction of the carriage;
Detecting means for detecting the presence and position of a non-ejection nozzle that does not eject ink in the plurality of nozzles;
When the detection unit detects that there is a non-ejection nozzle, recording is performed by a first scan of the recording head, and the recording medium is conveyed in an amount corresponding to the position of the non-ejection nozzle, A recording control means for performing recording in a second scan of the recording head by causing a nozzle other than the non-ejection nozzle to correspond to a portion that is not recorded by the non-ejection nozzle in one scanning;
An ink jet recording apparatus comprising:   A recording unit that completes recording in a recording area that can be recorded in one scan by a plurality of scans is provided, and a recording unit that completes in one scan and a plurality of scans according to the result of the detection unit. 2. The ink jet recording apparatus according to claim 1, wherein the recording means is switched to a completed recording means.   The inkjet recording apparatus according to claim 2, wherein a result of the detection unit is a position of the non-ejection nozzle.   4. The nozzle that performs recording in the second scan in a portion that has not been recorded by the non-ejection nozzle in the first scan is changed for each recording unit. The ink jet recording apparatus described. A carriage equipped with a recording head having a plurality of nozzles for discharging ink;
A moving step of reciprocating the carriage in the main scanning direction;
A transporting process for transporting the recording medium in a direction crossing the moving direction of the carriage;
A detection step of detecting the presence and position of a non-ejection nozzle that does not eject ink at the plurality of nozzles;
When the detection unit detects that there is a non-ejection nozzle, recording is performed by the first scan of the recording head, and the recording medium is conveyed in an amount corresponding to the position of the non-ejection nozzle, A recording control step in which nozzles other than the non-ejection nozzles correspond to portions that are not recorded by the non-ejection nozzles in one scanning, and recording is performed in the second scanning of the recording head;
A recording method comprising:

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