JP2008179069A - Liquid discharge device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid discharge device aiming to enhance the detection efficiency detecting missing dots. <P>SOLUTION: The liquid discharge device has a recording head 8 discharging ink from nozzle 27 by inputting discharge signals, a discharge defect detect means 47 detecting discharge defect nozzles of the recording head, and a control means controlling the recording head and the discharge defect detect means, the control means controls so as to carry out unit operation detecting the discharge defect nozzles classifying all the nozzles into a plurality of nozzle groups by each nozzle group so as to execute displacing timing among each unit detect operation every time when a predetermined timing comes. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fluid ejecting apparatus that can be used as an ink jet recording apparatus that mainly forms dots on a recording medium by ejecting ink droplets from nozzles corresponding to print data.

  As a fluid ejecting apparatus that ejects a fluid to a target, an ink jet recording apparatus that performs printing by ejecting ink onto a recording sheet is known.

  Such an ink jet recording apparatus has a relatively low noise during printing and can form small dots with a high density. Therefore, these ink jet recording apparatuses are used in many printing including color printing in recent years. Such an ink jet recording apparatus includes an ink jet print head that receives supply of ink from an ink cartridge, and a paper feed mechanism that moves a storage medium perpendicular to the scanning direction of the print head, and records the print head on the carriage. Recording is performed by ejecting ink droplets onto the recording medium by generating mechanical pressure and thermal energy to the print head while moving in the width direction (main scanning direction) of the medium. On the carriage, for example, a print head capable of ejecting black ink and each color ink of yellow, cyan, and magenta is installed, and not only text printing with black ink but also full ink printing by changing the ejection ratio of each ink Is possible.

  As a recording head used in such an ink jet recording apparatus, there is a piezoelectric element method in which a part of a wall surface of a pressure generating chamber is deformed using a piezoelectric element and ink is ejected as a method for ejecting ink.

  In such an ink jet recording head, bubbles are generated in the cavity (pressure generating chamber) of the recording head, floating paper powder or dust adheres to the vicinity of the nozzle, or the nozzle (inner ink) is dried. In some cases, ink droplets are not ejected from the nozzles, and dots are not formed on the print medium. Ink droplet ejection failure is generally called “dot missing”. When a dot missing phenomenon occurs, recovery is performed by a cleaning device. For example, when a dot drop phenomenon occurs due to the generation of bubbles, the ink in the nozzle is sucked with a pump to discharge the bubbles inside the cavity, and then the ink attached to the nozzle surface is removed with a wiping member called a wiper. Wiping off and discharging the ink droplets, called flushing, without printing, discharges the mixed ink. This series of cleaning steps recovers the dot drop phenomenon due to bubbles.

As a method for detecting dot omission as described above, conventionally, a method for determining the presence or absence of dot omission by observing ink droplets ejected from a recording head with an optical sensor or a laser sensor (for example, Patent Document 1 below) For example, a method of printing a detection pattern for detecting missing dots and determining the printed detection pattern by scanning such as an optical reading sensor (for example, Patent Document 2 below) has been adopted.
JP 2003-127430 A JP 2006-095815 A

  However, in the above conventional apparatus, since dot missing of all the nozzles is detected at a common detection timing, it takes a long time to detect the dot missing from the start to the end, so that the efficiency is poor. In particular, in the case of an apparatus having a configuration in which a plurality of recording heads are combined, the total number of nozzles also increases, so that the detection time is further increased. In addition, since printing is interrupted during detection, if printing is resumed after the detection is completed, there is a problem in that the ink drying state is not continuous before and after the interruption, resulting in uneven printing.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a fluid ejection device that improves the detection efficiency of dot missing detection.

In order to achieve the above object, a fluid ejecting apparatus of the present invention includes an ejecting head that ejects fluid from a nozzle in response to an ejection signal input, an ejection failure detection unit that detects an ejection failure nozzle of the ejection head, the ejection head, Control means for controlling the injection failure detection means,
The above control means classifies all nozzles into a plurality of nozzle groups and performs unit detection operation for detecting ejection failure nozzles with each nozzle group as one unit between each unit detection operation every time a predetermined detection timing arrives. The gist is to control the execution so that the time is shifted.

  According to the present invention, the unit detection operation in which all nozzles are classified into a plurality of nozzle groups and each nozzle group is detected as one unit to detect defective injection nozzles is performed each time a predetermined detection timing arrives. The unit detection operation time for one time is reduced to a fraction compared to detecting dot missing of all nozzles at a common detection timing as in the prior art. The detection efficiency is greatly improved, and this is particularly effective in an apparatus having a large number of nozzles. Even if the injection to the target is interrupted during the detection, the interruption time can be short, so that unevenness is less likely to occur when the injection is resumed after the end of detection.

  In the present invention, when the control means performs control to execute an ejection operation for ejecting fluid to a predetermined target between one unit detection operation and the next unit detection operation, each unit detection operation is performed. Since the injection operation is executed while the timing is shifted, the injection to the target can be executed while increasing the detection efficiency.

In the present invention, when the control means executes a series of fluid ejection commands for a predetermined target, it performs control so that the ejection operation is interrupted and unit detection operations are sequentially performed every time a predetermined detection timing arrives. Is
Since the interruption time of the injection operation is short, unevenness is less likely to occur when the injection is resumed after the end of detection.

In the present invention, further comprising a carriage that moves the ejection head between an ejection area that ejects fluid to a predetermined target and a detection area that is provided outside the ejection area and performs a unit detection operation,
While the control unit moves the ejection head to the ejection area and performs a series of fluid ejections on a predetermined target, the control means moves the ejection head to the detection area and performs unit detection operation every time a predetermined detection timing arrives. When controlling to run,
Since the interruption time of the injection operation is short, unevenness is less likely to occur when the injection is resumed after the end of detection.

In the present invention, when the control means performs control so as to execute the unit detection operation by classifying the nozzles as one unit nozzle group for each one or a plurality of nozzle rows,
Since the unit detection operation is performed for each nozzle row to detect the ejection failure nozzle, the control is easy and the control efficiency is improved.

In the present invention, when the control means performs control so as to execute the unit detection operation by classifying the nozzles as one unit nozzle group for each kind of one or a plurality of fluids to be ejected,
Since a unit detection operation is performed for each type of fluid to detect an ejection failure nozzle, control is easily performed and control efficiency is improved.

In the present invention, when the control means performs control so as to execute the unit detection operation by classifying one unit nozzle group according to the nozzle position in the nozzle row,
For example, the unit detection operation is simultaneously performed for every other nozzle, and recovery is performed when a defective nozzle is detected, thereby preventing adjacent nozzles from causing defective injection simultaneously. If adjacent nozzles cause injection failure at the same time, the unevenness of injection becomes large and the probability of failure becomes high. Therefore, detection efficiency can be improved while preventing this.

In the present invention, when the control means performs control so that the unit detection operation is performed by classifying one unit nozzle group according to whether the nozzle position is an odd-numbered nozzle position or an even-numbered nozzle position from the end of the nozzle array. ,
Unit detection operation is performed simultaneously for every other nozzle, and recovery is performed when a defective nozzle is detected, thereby preventing adjacent nozzles from causing defective injection at the same time. If adjacent nozzles cause injection failure at the same time, the unevenness of injection becomes large and the probability of failure becomes high. Therefore, detection efficiency can be improved while preventing this.

In the present invention, a plurality of the ejection heads are provided,
When the control means performs control so as to classify the nozzles as one unit nozzle group for each one or a plurality of ejection heads and execute the unit detection operation,
With multiple jet heads, the number of nozzles is extremely large, and detection of all jet heads must be performed for a very long time, but detection is performed by performing unit detection for each jet head. Efficiency can be greatly improved.

In the present invention, when the predetermined detection timing is a timing at which injection to a target of a predetermined unit is completed,
By performing the unit detection operation at a perfect timing when the injection of a predetermined unit to the target is completed, it is easy to control, and the efficiency of a series of operations for injection to the target can be improved, which is convenient.

In the present invention, when the predetermined detection timing is a timing at which the injection of the predetermined unit of injection data is completed,
By performing the unit detection operation at a good timing when the injection based on the injection data of a predetermined unit is completed, control is easy to perform, and the efficiency of a series of operations for injection with respect to the target can be improved.

In the present invention, when the predetermined detection timing is a timing at which the injection by the predetermined unit of the injection job ends,
Control is facilitated by executing the unit detection operation at a good timing when the ejection by the ejection job of a predetermined unit is completed.

In the present invention, when the predetermined detection timing is a timing at which the injection of the predetermined number of injection shots is completed,
Control is facilitated by executing the unit detection operation at a good timing when the injection with the predetermined number of shots is completed. In addition, the unit detection operation can be performed at an appropriate timing at which a defective nozzle needs to be detected, and the injection quality can be reliably managed.

In the present invention, when the predetermined detection timing is a timing at which injection of a predetermined time is finished,
Control is facilitated by executing the unit detection operation at a well-finished timing at which the injection for a predetermined time is completed. Further, the unit detection operation can be performed at an appropriate timing when the defective injection nozzle must be detected, and the injection quality can be reliably managed.

  In the present invention, the control means is used when executing a series of fluid ejection commands for a predetermined target so as not to execute the unit detection operation for the nozzle group corresponding to the unused fluid. By omitting the detection operation for the nozzles that have not been performed, the detection efficiency can be further improved.

  In the present invention, when a defective injection nozzle is found, the control means automatically performs a recovery operation by a recovery means for recovering the injection characteristic of the defective injection nozzle when the number of defective injection nozzles and the distribution state are unacceptable. When control is performed so that the injection quality is controlled, it is possible to stably maintain and manage the injection quality by automatically performing a recovery operation when a defective nozzle having an influence on the injection quality is found.

  In the present invention, the control means performs a recovery operation by a recovery means for recovering the injection characteristics of the defective injection nozzle when the defective injection nozzle is found and the number of defective injection nozzles and the distribution state are within a predetermined allowable range. When the control is performed so that the notification is performed without executing the control, it is possible to determine whether to recover or continue as it is at the operator's judgment when the number of defective nozzles is within a predetermined allowable number. Can be flexibly maintained.

  In the present invention, the control means controls to start the next injection operation as it is when a defective injection nozzle is found and the number and state of the defective injection nozzles are within an allowable range in which the influence on the injection quality is small. In this case, the injection efficiency can be improved by omitting the recovery operation when the number of defective nozzles is within an allowable number that does not affect the injection quality.

  Next, embodiments of the present invention will be described in detail.

  Hereinafter, an embodiment of an ink jet printing apparatus as a fluid ejecting apparatus embodying the present invention will be described.

  FIG. 1 shows an embodiment of an ink jet recording apparatus as a large textile printing apparatus capable of printing on a long cloth.

  Between the bases 1 and 2 on both sides, a supply unit 3 for supplying a recording medium such as a cloth as a predetermined target, a printing region 4 as an ejection region for ejecting ink as a fluid to the target, and a discharged recording medium A winding unit 5 for winding is disposed, a control panel 6 is provided on the side of the supply unit 3, and a cartridge holder 16 is provided on each of the bases 1 and 2.

  These cartridge holders 16 include a black ink cartridge 7BK, a cyan ink cartridge 7C as a color ink cartridge, a magenta ink cartridge 7M, a yellow ink cartridge 7Y, a light cyan ink cartridge 7LC, a light magenta ink cartridge 7LM, a green ink cartridge 7G, and an orange ink cartridge. 7OR (hereinafter sometimes simply referred to as “ink cartridge 7”) is detachably mounted.

  As a result, the apparatus according to the present embodiment can perform ink jet recording with eight inks of black ink, cyan ink, magenta ink, yellow ink, light cyan ink, light magenta ink, green ink, and orange ink. It has become.

  Reference numeral 9 in the figure denotes a recording head 8 (see FIGS. 2 and 3) that receives ink supplied from an ink cartridge 7 of the cartridge holder 16 via an ink supply device 17 (see FIG. 2), which will be described later. A carriage 9 is supported by a guide member 10 so as to be capable of reciprocating in the width direction of the recording cloth, which is the main scanning direction.

  In the left and right non-printing areas outside the printing area, a slight clogging of the nozzles occurring during printing is recovered by inputting an ejection signal irrelevant to the printing signal to the recording head 8 to forcibly eject ink. A flushing region for performing a flushing operation for the purpose is provided. A flushing box 11 for receiving ink ejected by flushing is disposed in the flushing area, and a waste liquid tank 12 for storing waste fluid ejected by flushing is disposed under the flushing box 11.

  A non-printing area on the right side (home position) shown in the figure outside the printing area 4 is provided with a cap 15 that seals the nozzle surface of the recording head 8, and the cap 15 is sealed with the cap 15. A capping device 14 is provided for performing a cleaning operation as a recovery operation for recovering the ejection failure of the nozzles by forcibly sucking ink from the nozzles with the suction pump 13 having a negative pressure.

  The cap 15 is provided outside the printing area 4, and there is an inspection area 74 (see FIG. 5) for performing a unit detection operation by an ejection failure detection means 47 (see FIG. 4) described later. The carriage 9 moves the recording head 8 between the printing area 4 and the inspection area 74.

  FIG. 2 is a flow path configuration diagram showing the ink supply device 17.

  This example shows only one of the eight colors. The ink cartridge 7 includes an ink pack 25 in which liquid ink is sealed as a fluid, and a case 24 that stores the ink pack 25. The ink pack 25 has an ink supply tube 22 connected to the ink discharge port 25a. Only the ink discharge port 25 a of the ink pack 25 is exposed to the outside, and the other portions are stored in the case 24 in an airtight state, whereby an airtight space is formed inside the case 24.

  The case 24 is connected to an air supply tube 21 communicating from the outside to the internal space. A pressure pump 18, a pressure sensor 19, and an atmosphere release valve 20 are connected to the air supply tube 21, and pressurized air (pressurized gas) is sent to the ink cartridge 7 through the air supply tube 21.

  When the pressurizing pump 18 is operated, pressurized air is introduced into the space in the ink cartridge 7 through the air supply tube 21, and the ink pack 25 is crushed by the air pressure (pressurizing force) of the pressurized air. Thus, the ink in the ink pack 25 is supplied to the sub tank 23 via the ink supply tube 22. The ink is temporarily stored in the sub tank 23 and is supplied to the recording head 8 in a state where the pressure is adjusted by a pressure adjusting mechanism (not shown).

  The recording apparatus drives a carriage motor 26 and a paper feed motor (not shown) based on print data fetched from a host computer 44 (see FIG. 3) or a memory card, and ejects ink from the recording head 8. Execute print processing.

  FIG. 3 is a view showing an example of the recording head 8 mounted on the carriage 9.

  As shown in FIG. 3A, each recording head 8 functions as an ejection head that ejects fluid from the nozzles 27 by inputting an ejection signal. In this example, the recording head 8 includes a plurality of recording heads 8. That is, in this example, three recording heads 8 are used for each color ink, and a total of 24 recording heads 8 are mounted. In this example, each recording head 8 has two nozzle rows (first row and second row). Each nozzle row includes 180 nozzles 27 arranged at a predetermined pitch P from the end of the row from the top to the bottom in the drawing.

  Three recording heads 8 that eject ink of the same color are arranged in the nozzle row direction so that the vicinity of the row ends of the nozzle rows are adjacent to each other. In this example, from the upper left in the figure, a black head row BK that ejects black ink, a cyan head row C that ejects cyan ink, a magenta head row M that ejects magenta ink, and a yellow head that ejects yellow ink. A light cyan head row LC for jetting light cyan ink, a light magenta head row LM for jetting light magenta ink, a green head row G for jetting green ink, and an orange for jetting orange ink. A head row OR is arranged.

  As described above, there are three recording heads 8 constituting each head row BK, C, M, Y, LC, LM, G, OR. I will call it No.2, No.2, and No.3.

  As shown in FIG. 3 (B), the vicinity of the row end of the nozzle row is adjacent to, for example, the # 180 nozzle at the row end of the No. 1 head and the # 1 nozzle at the row end of the No. 2 head. The nozzle pitch P is arranged in the direction. The No. 2 head and the No. 3 head are also arranged in the same positional relationship. Thus, the nozzle pitches P in the first row and the second row are continuous in the heads of Nos. 1 to 3.

  In this example, eight head groups of one head, one color ejection × 3 heads are provided for every eight colors, and eight-color printing using a total of 24 heads is shown. Four head groups of 6 heads may be provided to achieve 8-color printing using a total of 24 heads, or recording head 8 provided with 4 or more nozzle arrays may be used to eject 4 colors or more per head. It is also possible to configure a head group by combining the heads.

  FIG. 4 is a block diagram showing an example of the system configuration of the recording apparatus.

  The ejection failure detection means 47 described here functions as the ejection failure detection means 47 of the present invention that detects ejection failure nozzles in the recording head 8, and the cleaning control means 54 and the pump control means 49 are responsible for ejection failure. It also functions as a recovery means of the present invention that recovers the ejection characteristics of the nozzle. The print control means 46, the head drive means 48, the carriage control means 52, the treatment selection means 51, the notification means 53, etc. control the recording head 8, the ejection failure detection means 47, the recovery means, etc. It functions as a control means.

  In the figure, reference numeral 44 denotes a host computer which has a built-in printer driver 45. The size of the recording medium, monochrome / color printing selection, and recording mode are input by an input device (not shown) on the utility of the printer driver 45. Selection, font data, and print commands can be input. In the utility of the printer driver 45, a cleaning command for the cleaning control means 54 can be input.

  In response to the input of the print command, the printer driver 45 sends print data as fluid ejection data to the print control means 46. Further, the print control unit 46 generates bitmap data based on the print data, generates an ejection signal by the head driving unit 48 and inputs it to an ejection element such as a piezoelectric vibrator, and ejects ink droplets from the recording head 8. It is like that.

  At this time, the medium feed control means (not shown) controls the movement of the recording medium in the sub-scanning direction by controlling a medium feed motor (not shown) according to an instruction from the print control means 46. Further, in response to an instruction from the printing control means 46, the carriage control means 52 controls the carriage motor 26, which is a pulse motor, to control the carriage 9 to reciprocate in the main scanning direction.

  The head driving unit 48 functions as an ejection control unit in the present embodiment. In addition to a driving signal based on print data, the head driving unit 48 receives a flushing command signal from a flushing control unit (not shown) and generates an ejection signal for flushing. Output to the recording head 8. By this flushing operation, ink unrelated to printing is ejected from the nozzle 27 to the flushing box 11, thereby discharging the thickened ink near the nozzle 27 and restoring the ejection characteristics of the nozzle 27.

  Here, the mechanism by which the ejection capacity of the nozzle 27 is reduced will be described. During printing, the nozzle surface of the recording head 8 is released from the cap 15 and is moved back and forth by the carriage 9. If ink is not ejected in such a state, the solvent evaporates from the ink present in the opening of the nozzle 27, the viscosity gradually increases, and the ejection capacity decreases. The nozzles 27 that frequently eject ink droplets during printing are supplied with new ink one after another so that clogging does not occur much, but the nozzles 27 that rarely eject ink droplets tend to clog. Accordingly, the thickening of the nozzle 27 progresses as the nozzle 27 has a smaller ink discharge amount and a longer idle time, and the degree thereof varies from nozzle 27 to nozzle 27.

  In this example, the case has been described in which the liquid ejected by the ejection head is ink, and the ejection capability of the nozzle 27 is reduced due to the increased viscosity of the ink. However, the mechanism by which the ejection characteristics decrease depends on the type of liquid to be ejected. The present invention is applicable not only to ink but also to a device for ejecting various fluids, as long as the ejected characteristics of the nozzle 27 can be recovered by fluid ejection.

  The carriage control means 52 performs a movement control for reciprocating the carriage 9 in the main scanning direction during a printing operation, and also moves the carriage 9 to a flushing position other than the printing area at a predetermined flushing timing, and caps the recording head 8. Movement control to move to a position where a flushing operation is performed while facing 15 is performed.

  The carriage control means 52 performs movement control for moving the recording head 8 to the position of the cap 15 when the apparatus is powered off or when performing a suction operation. In addition, movement control is performed to move the nozzle row to be detected to a position facing the inspection region 74 existing in the cap 15 in a unit detection operation for detecting an ejection failure nozzle described later.

  The above suction operation is executed during the initial filling operation in which ink is first filled in the flow path of the recording head 8, the sub tank 23, etc. when the ink cartridge 7 is first mounted when the recording apparatus is used for the first time. The Also, when the ink cartridge 7 is replaced or when the used ink cartridge 7 is once removed and reloaded, air is mixed into the flow path of the recording head 8 along with the replacement or reloading and normal ejection is performed. Therefore, the mixed bubbles are forcibly sucked and removed from the recording head 8.

  In the above suction operation, when the recording apparatus is not used, even if the nozzle forming surface is sealed with the cap 15, the standing time measured by a standing timer (not shown) (from the previous power-off) If the time until the power is turned on is long, the solvent gradually evaporates from the ink existing in the vicinity of the opening of the nozzle 27 and the viscosity thereof increases, so that the discharge capability decreases. When the power is turned on, suction in the cleaning mode is executed under the control of the cleaning control means 54. In addition, if the printing operation is continued, bubbles remaining in the flow path may gradually accumulate in the upstream part of the internal filter, so cleaning control is performed for cleaning that periodically removes the bubbles by forced suction. The suction by the cleaning mode may be executed by the control by the means 54.

  The suction operation may be executed as so-called manual cleaning when the user operates the cleaning command switch 50.

  When the so-called dot omission detection controlled by the ejection failure detection means 47 described later is performed, the suction operation described above is controlled by the cleaning control means 54 when the presence of ejection failure nozzles due to clogging of the nozzles 27 is detected. This is executed when the recovery operation of the ejection failure of the nozzle 27 is performed by performing the capping by the suction and the suction in the cleaning mode by the suction pump 13. That is, the suction in the cleaning mode functions as a recovery operation for recovering the ejection characteristics of the ejection failure nozzle of the present invention.

  The above suction operations may be controlled by the pump control means 49 because the suction conditions may differ depending on the situation, such as suction in a cleaning mode such as initial filling, replacement of the ink cartridge 7, cleaning, and ejection failure detection. By controlling the rotation speed and operating time of the suction pump 13, suction in various suction modes can be performed.

  The suction operation is controlled by the cleaning control means 54 as follows. That is, the carriage 9 is moved to a position where the carriage 9 faces the cap 15, and the cap 15 is raised by, for example, a cam mechanism or the like by an operation of a maintenance motor (not shown) to seal the nozzle forming surface of the recording head 8 with the cap 15. The inside of the cap 15 is sucked by the action of the suction pump 13 driven by a motor, and ink or the like is forcibly discharged from the nozzle.

  After performing suction for a predetermined time, the suction pump 13 is driven in a state where the inside of the cap 15 is opened to the atmosphere by a valve mechanism (not shown) to perform idle suction, and the ink remaining in the space in the cap 15 is discharged. Thereafter, when the cap 15 is lowered, the ink is adhered to the nozzle forming surface in this state, and therefore the wiping member (not shown) is raised to a position where the tip portion can contact the nozzle forming surface by driving the maintenance motor. After that, by controlling the movement of the carriage 9, the ink adhering to the nozzle forming surface is wiped off by the wiping member.

  FIG. 5 is a diagram for explaining the details of the ejection failure detection means 47.

  The ejection failure detection means 47 includes a cap 15 serving as a droplet receiving unit disposed at the home position, an inspection area 74 provided inside the cap 15, and a nozzle substrate of the inspection area 74 and the recording head 8. The voltage application circuit 75 for applying a voltage between the first and second terminals 33 and the voltage detection circuit 76 for detecting the voltage of the inspection region 74 are configured.

  The cap 15 is a tray-like member having an open upper surface, and is made of an elastic member such as an elastomer. An ink absorber 77 is disposed inside the cap 15. The ink absorber 77 includes an upper absorber 77a and a lower absorber 77b, and a mesh-like electrode member 78 is disposed between the absorbers 77a and 77b. The upper absorbent body 77a is made of a conductive sponge so as to have the same potential as the electrode member 78. This sponge is highly permeable so that the landed ink droplets can move downward quickly. In this embodiment, an ester urethane sponge is used.

  The inspection region 74 corresponds to the surface of the upper absorbent body 77a. The lower absorbent body 77b has higher ink retention than the upper absorbent body 77a, and is made of a nonwoven fabric such as felt. The electrode member 78 is formed as a lattice mesh made of a metal such as stainless steel. For this reason, the ink once absorbed by the upper absorbent body 77 a is absorbed and held by the lower absorbent body 77 b through the gap between the grid-like electrode members 78.

  The voltage application circuit 75 is electrically connected via a DC power source (for example, 400 V) and a resistance element (for example, 1 MΩ) so that the electrode member 78 is a positive electrode and the nozzle substrate 33 of the recording head 8 is a negative electrode. Yes. Here, since the electrode member 78 is in contact with the conductive upper absorber 77 a, the surface of the upper absorber 77 a, that is, the inspection region 74 is also at the same potential as the electrode member 78.

  The voltage detection circuit 76 integrates and outputs the voltage signal of the electrode member 78, an inverting amplification circuit 81 that inverts and amplifies the signal output from the integration circuit 80, and the inverting amplification circuit 81. And an A / D conversion circuit 82 for A / D converting and outputting the signal output from.

  The integration circuit 80 outputs a large voltage change by integrating the voltage change due to the flight / landing of a plurality of ink knobs since the voltage change due to the flight / landing of one ink droplet is small. The inverting amplifier circuit 81 inverts the sign of the voltage change and amplifies and outputs the signal output from the integration circuit 80 with a predetermined amplification factor. The A / D conversion circuit 82 converts the analog signal output from the inverting amplification circuit 81 into a digital signal and outputs it as a detection signal.

  The ejection failure detection means 47 can detect ejection failure nozzles as follows, for example.

  The detection operation is an operation for inspecting whether or not all the nozzles 27 arranged in the recording head 8 are clogged. When processing is started, the carriage control unit 52 first drives the carriage motor 26 to perform recording. The carriage 9 is moved so that the nozzle row to be inspected in the nozzle row of the head 8 faces the inspection region 74, and the mask circuit and the piezoelectric element (both not shown) of one nozzle 27 in the nozzle row to be inspected. The ink droplets charged from the nozzles 27 are ejected at a discharge number Sn of one segment (for three shots).

  Here, the transition of the voltage in the electrode member 78 when the charged ink droplets fly from the nozzles 27 of the recording head 8 and reach the upper absorber 77a in the inspection region 74 will be described.

  FIG. 6 is a schematic diagram for explaining the principle that an induced voltage is generated by electrostatic induction when an ejection failure nozzle detection operation is executed by the ejection failure detection means 47.

  As shown in FIG. 6A, the ink droplet before flying from the nozzle 27 by the recording head 8 is negatively charged by the voltage application circuit 75. For this reason, as shown in FIG. 6B, as the negatively charged ink droplets fly from the nozzle 27 and approach the upper absorber 77a, a positive charge is generated on the surface of the upper absorber 77a by electrostatic induction. To increase. As a result, the voltage between the recording head 8 and the electrode member 78 becomes higher than the initial voltage level due to the induced voltage generated by electrostatic induction.

  Thereafter, as shown in FIG. 6C, when the negatively charged ink droplet reaches the upper absorber 77a, the positive charge of the upper absorber 77a is neutralized by the negative charge of the ink droplet. As a result, the voltage between the recording head 8 and the electrode member 78 falls below the initial voltage value. Thereafter, the voltage between the recording head 8 and the electrode member 78 returns to the applied voltage value. The amplitude of the output signal at this time depends on the magnitude of the voltage applied between the recording head 8 and the electrode member 78 and the distance from the recording head 8 (nozzle 27) to the upper absorber 77a (inspection region 74). In addition, it depends on the presence and size of flying ink droplets.

  For this reason, when the nozzle 27 is clogged and the ink droplet does not fly or the ink droplet is smaller than a predetermined size, the amplitude of the output signal is smaller than that in the normal state. The presence or absence of clogging can be determined. However, since the amplitude of the output signal due to the ink droplet for one shot is extremely small, all of the first to third pulses P1, P2, P3 of one segment representing the drive waveform are output to generate the ink droplet for three shots. By discharging, the output signal is taken out as an integrated value of ink droplets for three shots. Since the signal output from the voltage detection circuit 76 passes through the inverting amplification circuit 81, the direction of the amplitude is reversed.

  In the present embodiment, the detection operation by the ejection failure detection means 47 is a unit detection operation in which all nozzles of all the recording heads 8 are classified into a plurality of nozzle groups, and each nozzle group is detected as one unit to detect ejection failure nozzles. Executed. Then, control is performed so that the unit detection operation is executed with a time lag between the unit detection operations each time a predetermined detection timing arrives.

  In this example, the nozzles included in one recording head 8 are classified as one unit nozzle group, and the nozzles are classified as one unit nozzle group for each recording head 8, and the unit detection operation is executed. Control is performed so as to execute a printing operation as an ejection operation for ejecting ink onto a target recording medium between one unit detection operation and the next unit detection operation. That is, in the 24 recording heads 8 shown in FIG. 3, a unit detection operation is executed for each recording head 8, and a printing operation is executed between each unit detection operation.

  FIG. 7 is a diagram illustrating an example of a process in the case of performing ejection failure detection for each of the 24 recording heads 8 illustrated in FIG.

  First, printing is started, printing is performed for a predetermined time, and then unit detection of the BK row No. 1 head is executed. When the unit detection is completed, the printing is resumed again, and when the printing is performed for a predetermined time, the unit detection of the C row-1 head is executed. As described above, during the execution of a print command, which is a series of fluid ejection commands for the recording medium, the print operation is interrupted and unit detection operations are sequentially executed every time a predetermined detection timing arrives. In this example, the predetermined detection timing is a timing at which ejection for a predetermined time, that is, printing is completed.

  When the unit detection of the M-row No. 1 head, the Y-row No. 1 head, and the No. 1 head of each head row is completed, the BK row No. 2 head, the C row No. 1 head, and so on. Unit detection of No. 2 head of each head row is sequentially performed, and unit detection of No. 3 head of each head row is sequentially carried out by repeating the unit detection of BK row No. 3 head, C row No. 3 head. Returning to the -1 head, unit detection is performed sequentially in the same manner, and the process is repeated until printing is completed.

  At this time, a series of fluid ejection, that is, printing, is performed on the recording medium while moving the recording head 8 to the printing area 4 and reciprocating, and the inspection area 74 is present every time a predetermined detection timing comes. The unit detection operation is executed by moving to the home position to be held, that is, the position facing the cap 15.

  Next, a procedure when an ejection failure nozzle is detected by the unit detection operation will be described.

  When a defective injection nozzle is found by the unit detection operation, the treatment selection means 51 automatically executes the recovery process according to the number or state, notifies the operator without executing the recovery process, or recovers the recovery process. Or a measure for restarting the printing process without performing notification.

  That is, when the number of defective injection nozzles and the distribution state are unacceptable, the recovery operation by the recovery means for recovering the injection characteristics of the defective injection nozzle is automatically executed, and the number of defective injection nozzles and the distribution state are within a predetermined allowable range. If it is within the range, the operator is notified by the notifying means 53 without executing the recovery operation, and if the number and state of defective nozzles are within an allowable range with little influence on the injection quality, that is, the print quality, The next printing operation is started.

  As a determination criterion at this time, for example, when the number of ejection failure nozzles detected is a small number that hardly affects print quality with respect to the number of nozzles constituting the nozzle group, A printing operation can be started. In addition, if the number of detected defective nozzles is within a range that is not negligible in print quality with respect to the number of nozzles constituting the nozzle group, but is likely to be acceptable to some extent, the operator is notified to judge If the level can be ignored, printing is started. If the level cannot be ignored, the recovery operation is performed by operating the cleaning command switch 50 by the operator. Further, when the number of ejection failure nozzles detected is large enough to affect the print quality with respect to the number of nozzles constituting the nozzle group, the recovery operation is automatically executed.

  In addition, as a distribution state of defective nozzles, for example, when it is detected that adjacent nozzles 27 have a plurality of defective injections, there is a high possibility that the print quality will be affected, so automatic regardless of the number of defective nozzles. Recovery operation is performed automatically.

  Further, the number of ejection failure nozzles and the like serving as the above judgment criteria are controlled by an operator to be set on the setting screen of the driver 45, stored in a RAM (not shown), and judged using the stored set values. For example, if the design has a large area of one color, printing failure due to poorly ejected nozzles tends to be noticeable, and if it is a fine pattern, it is difficult to notice even if there are some poorly ejected nozzles. It can be set by the operator.

  FIG. 8 is a flowchart for explaining the ejection failure nozzle detection process in the recording apparatus of the embodiment.

  First, when print data is transmitted from the host computer 44 and a printing operation is started, a timer (not shown) is activated to start a time count for measuring the detection timing. If the detection timing does not come, the printing operation is continued. When the detection timing comes after a predetermined time has passed, the process proceeds to the next step (step 10). In the next step, printing is interrupted, and the unit detection operation of the first detection target head BK row No. 1 head is executed (step 20).

  FIG. 9 is a flowchart for explaining the unit detection operation process. When the unit detection routine is started, first, the carriage 9 is moved so that the search target nozzle row (for example, the first row) faces the inspection position facing the inspection region 74 (step 21). Next, the # 1 nozzle in the inspection target nozzle row is set as the inspection target nozzle, and a predetermined number of ink droplets are ejected (step 22).

  The injection failure is detected according to the principle described above, and the presence or absence of abnormality is determined (step 23). If there is an abnormality in step 23, the current nozzle is stored as an abnormal nozzle in the RAM (step 24), and the process proceeds to step 25. If there is no abnormality in step 23, the process proceeds to step 25 as it is.

  In step 25, it is determined whether or not all nozzles in the current nozzle row have been detected (step 25). If all the nozzles are not detected in step 25, the nozzle to be inspected is updated in step 26 to make nozzle # 2 the inspection target nozzle, and the process returns to step 22 to return # in the inspection target nozzle row (first row). Steps 22 to 26 are repeated until the detection process for 180 nozzles is completed.

  If all the nozzles are detected in step 25 (when the detection process is finished up to # 180 nozzles), it is determined whether or not all nozzle rows in the current recording head 8 have been detected (step 27). If all the nozzle rows are not detected in step 27, the nozzle row to be inspected is updated in step 28, the second row becomes the inspection subject nozzle row, and the flow returns to step 21 to return to the inspection subject nozzle row (second row). Steps 22 to 26 are repeated until the detection process is finished up to # 180 nozzles. If all the nozzle arrays are detected in step 27, the unit detection routine is terminated.

  When the unit detection operation is completed, the process proceeds to step 30, and from the number and distribution of ejection failure nozzles stored in the RAM, whether the recovery operation is executed as the next treatment, printing is continued, or the operator is notified. select.

  When continuation is selected in step 30, the recovery process and the notification process are not executed, the detection target head is updated, the next detection target head is set to the C row -1 head, and the timer is reset (S70). If printing is not finished, the process returns to step 10, and the processing of steps 10 to 80 is repeated until printing is finished. If printing is finished, the process is finished.

  When recovery is selected in step 30, the recovery operation (suction in the cleaning mode) described above is executed to recover the defective injection nozzle (step 60), and the process proceeds to step 70.

  When notification is selected in step 30, notification by the notification means 53 is executed (specifically, an alarm is sounded or an alarm lamp is turned on) (step 40), and an instruction to restore or continue by the operator is waited for ( Step 50). In step 50, when a recovery command is input, the process proceeds to step 60, and when a continuation command is input, the process proceeds to step 70. The recovery command is performed by operating a cleaning command switch 50 provided on the control panel 6, and the continuation command is also performed by operating a continuation command switch (not shown) provided on the control panel 6.

  In the above description, the case where the unit detection processing is executed for all the 24 recording heads 8 has been described. However, for example, when monochrome printing is being performed, the color head is not subject to unit detection processing. In the execution of a series of print commands for the medium, control may be performed so that the unit detection operation is not executed for the nozzle group corresponding to the unused ink.

  In the above description, an example in which unit detection processing is performed using a plurality of recording heads 8 and nozzles provided in one recording head 8 as a unit nozzle group has been described. The unit detection process may be performed using the nozzles provided in the nozzle group as one unit nozzle group. In these cases, the number of nozzle rows formed in one recording head 8 is not limited to two, but may be one or three or more.

  In addition to performing unit detection processing using nozzles provided in one or a plurality of recording heads 8 as a unit nozzle group, the following method can be used as a method for classifying nozzle groups.

  That is, it is also possible to classify the nozzles as one unit nozzle group for each one or a plurality of nozzle rows and perform unit detection processing as one unit nozzle group. That is, for example, unit detection processing can be performed for each nozzle row, or unit detection processing can be performed for each of a plurality of nozzle rows. In this case, the recording head 8 may be one or plural. Further, the number of nozzle rows formed in one recording head 8 is not limited to two, and may be three or more.

  It is also possible to perform control so that the unit detection operation is performed by classifying nozzles as one unit nozzle group for each type of ink to be ejected. That is, for example, a unit detection operation can be performed for each ink color, or a unit detection operation can be performed for each ink type, such as pigment ink and dye ink. Further, the timing of the unit detection operation can be shifted with the black ink and the color ink, and the timing of the unit detection operation can be shifted with the ink and the functional liquid other than the ink. In this case, the recording head 8 may be one or plural.

  It is also possible to perform control so that the unit detection operation is performed by classifying one unit nozzle group according to the nozzle position in the nozzle row. That is, for example, the unit detection operation time can be shifted depending on the number of nozzles from the end of the row. In this case, the recording head 8 may be one or plural.

  In this case, it is also possible to perform control so that the unit detection operation is performed by classifying one unit of nozzle group depending on whether the nozzle position is an odd-numbered nozzle position or an even-numbered nozzle position from the end of the nozzle array. That is, the timing of the unit detection operation is shifted between the first, third, fifth,... Odd-numbered nozzles and the second, fourth, sixth,. Can do.

  Moreover, although the example which measured the detection timing by progress of predetermined time was demonstrated in the above-mentioned description, it can also be as follows as a method of measuring a detection timing.

  That is, the timing at which the injection to the target of the predetermined unit is completed can be set as the detection timing. That is, for example, when the target is a cloth, the unit detection operation is executed every time printing on a predetermined length of cloth is completed, or when the target is paper, the unit is printed every time printing on a predetermined number of sheets is completed. The detection operation can be executed.

  Moreover, the timing at which the injection by the predetermined unit of injection data is ended can also be set as the detection timing. That is, for example, a unit detection operation can be executed every time printing with a predetermined unit of print data is completed.

  Moreover, the timing at which the ejection by the ejection job of a predetermined unit is completed can be set as the detection timing. That is, for example, the unit detection operation can be executed every time printing by a predetermined unit print job is completed.

  Also, the timing at which the injection of the predetermined number of injection shots is completed can be set as the detection timing. That is, for example, a unit detection operation can be performed every time the number of shots of a predetermined unit of ink droplets is completed.

  FIG. 10 is a diagram showing another example of the ejection failure detection means 47, and the ejection failure detection method that can be applied to the present invention, that is, the dot missing detection method, is limited to the above-described method using the induced voltage. In other words, various detection methods can be applied.

  10A, a laser light source 28 and a detector 29 are arranged between the cap 15 and the recording head 8, and ink droplets from the nozzles 27 are ejected while irradiating laser light from the laser light source 28. Detects a state where the laser beam is blocked by the detector 29, and detects a defective injection nozzle.

  In FIG. 10B, a detection pattern 31 is printed on the recording medium 30 for detection, and the detection pattern 31 is read by an optical reader 32 to detect an ejection failure nozzle.

  According to the above embodiments, the following effects can be obtained.

  That is, a unit detection operation for classifying all nozzles into a plurality of nozzle groups and detecting defective nozzles with each nozzle group as one unit is performed between each unit detection operation every time a predetermined detection timing arrives. Because they are executed in a shifted manner, the unit detection operation time for one unit is reduced to a fraction of that of detecting the missing dots of all nozzles at the common detection timing as in the conventional case, and the detection efficiency is greatly increased. This is particularly effective in an apparatus having a large number of nozzles. Even if printing on the recording medium is interrupted during detection, the interruption time can be short, so that unevenness is less likely to occur when printing is resumed after detection.

  Further, when the control means controls to execute a printing operation of ejecting ink onto a predetermined recording medium between one unit detection operation and the next unit detection operation, Since the printing operation is performed while the time is shifted, it is also possible to execute printing on the recording medium while increasing the detection efficiency.

In the case where the control means controls to execute the unit detection operation sequentially by interrupting the printing operation every time a predetermined detection timing arrives while executing a series of print commands for the predetermined recording medium. ,
Since the interruption time of the printing operation is short, unevenness is less likely to occur when ejection is resumed after the detection is completed.

The carriage 9 further includes a carriage 9 that moves the recording head 8 between a printing area 4 that ejects ink onto a predetermined recording medium and an inspection area 74 that is provided outside the printing area 4 and performs a unit detection operation. ,
The control means moves the recording head 8 to the inspection area 74 every time a predetermined detection timing arrives while moving the recording head 8 to the printing area 4 and executing a series of printing on a predetermined recording medium. When controlling to execute the unit detection operation,
Since the interruption time of the printing operation is short, unevenness is less likely to occur when ejection is resumed after the detection is completed.

Further, when the control means performs control so as to execute the unit detection operation by classifying the nozzles as one unit nozzle group for each one or a plurality of nozzle rows,
Since the unit detection operation is performed for each nozzle row to detect the ejection failure nozzle, the control is easy and the control efficiency is improved.

In addition, when the control unit performs control so as to execute the unit detection operation by classifying the nozzles as one unit nozzle group for each type of one or a plurality of ejected inks,
Since the unit detection operation is performed for each type of ink to detect ejection failure nozzles, control is easy and control efficiency is improved.

Further, when the control means performs control so as to execute a unit detection operation by classifying one unit nozzle group according to the nozzle position in the nozzle row,
For example, the unit detection operation is simultaneously performed for every other nozzle, and recovery is performed when a defective nozzle is detected, thereby preventing adjacent nozzles from causing defective injection simultaneously. If adjacent nozzles cause injection failure at the same time, the unevenness of injection becomes large and the probability of failure becomes high. Therefore, detection efficiency can be improved while preventing this.

Further, when the control means performs control so that the unit detection operation is performed by classifying one unit nozzle group depending on whether the nozzle position is an odd-numbered nozzle position or an even-numbered nozzle position from the end of the nozzle array,
Unit detection operation is performed simultaneously for every other nozzle, and recovery is performed when a defective nozzle is detected, thereby preventing adjacent nozzles from causing defective injection at the same time. If adjacent nozzles cause injection failure at the same time, the unevenness of injection becomes large and the probability of failure becomes high. Therefore, detection efficiency can be improved while preventing this.

A plurality of the recording heads 8;
When the control means performs control so as to classify the nozzles as one unit nozzle group for each one or a plurality of recording heads 8 and execute the unit detection operation,
The plurality of recording heads 8 has a very large number of nozzles, and all the recording heads 8 need to be detected for a very long time. However, a unit detecting operation must be performed for each recording head 8. As a result, the detection efficiency can be greatly improved.

Further, when the predetermined detection timing is a timing at which ejection to a predetermined unit of the recording medium is completed,
By performing the unit detection operation at the perfect timing when ejection of a predetermined unit of the recording medium is completed, it is easy to control, and the efficiency of a series of operations for printing on the recording medium can be improved, which is easy to use. .

Further, when the predetermined detection timing is a timing at which recording by recording data of a predetermined unit is completed,
By executing the unit detection operation at a perfect timing when recording with recording data of a predetermined unit is completed, control is easy to perform, and the efficiency of a series of operations for recording on the recording medium can be improved, which is convenient.

In addition, when the predetermined detection timing is a timing when recording by a recording job of a predetermined unit is completed,
Control is facilitated by executing the unit detection operation at a good timing when recording by a recording job of a predetermined unit is completed.

Further, when the predetermined detection timing is a timing at which the injection of the number of injection shots of a predetermined unit is completed,
Control is facilitated by executing the unit detection operation at a good timing when the injection with the predetermined number of shots is completed. In addition, the unit detection operation can be performed at an appropriate timing at which a defective nozzle needs to be detected, and the injection quality can be reliably managed.

Further, when the predetermined detection timing is a timing at which injection of a predetermined time is finished,
Control is facilitated by executing the unit detection operation at a well-finished timing at which the injection for a predetermined time is completed. Further, the unit detection operation can be performed at an appropriate timing when the defective injection nozzle must be detected, and the injection quality can be reliably managed.

  The control means is used when executing a series of ink ejection commands for a predetermined recording medium so as not to execute a unit detection operation for nozzle groups corresponding to unused ink. The detection efficiency can be further improved by omitting the detection operation for the nozzles that are not.

  In addition, when a defective injection nozzle is found, the control unit automatically performs a recovery operation by a recovery unit that recovers the injection characteristics of the defective injection nozzle when the number of defective injection nozzles and the distribution state are unacceptable. In the case of performing control so that the injection is performed, it is possible to stably maintain and manage the injection quality by automatically performing a recovery operation when a defective injection nozzle that affects the injection quality is found.

  The control means executes a recovery operation by a recovery means for recovering the injection characteristics of the defective injection nozzle when the defective injection nozzle is found and the number of defective injection nozzles and the distribution state are within a predetermined allowable range. When the control is performed without notification, it is possible to decide whether to recover or continue as it is based on the judgment of the operator when the number of defective nozzles is within a predetermined allowable number, and the injection quality is flexible. Can be maintained.

  Further, the control means controls to start the next printing operation as it is when an ejection failure nozzle is found, or when the number and state of ejection failure nozzles are within an allowable range in which the influence on ejection quality is small. In this case, when the number of defective nozzles is within an allowable number that does not affect the injection quality, the injection efficiency can be improved by omitting the recovery operation.

  In each of the above embodiments, the recovery operation for the defective ejection nozzle detected by detecting the missing dot is performed by the suction in the cleaning mode. However, the present invention is not limited to this, and the recovery by the flushing ejection can be applied.

  In each of the above-described embodiments, the case where ink is used as the fluid to be ejected has been described as an example. However, for example, dot missing detection when various functional fluids other than printing ink such as moisturizing liquid and cleaning liquid are ejected is described. It can also be applied to.

  In each of the above-described embodiments, the recording head 8 has been described by exemplifying the one that uses a piezoelectric vibrator as a pressure generating element that is a driving element that ejects fluid. However, a fluid ejecting apparatus that uses a heating element as a pressure generating element. It can also be applied to.

  In addition, a program that causes a computer device to execute the ejection failure detection method that is executed by the fluid ejection device described above can be recorded on a recording medium or provided through a communication network.

  The fluid targeted by the fluid ejecting apparatus of the present invention is not limited to the above-described liquid such as ink, but is intended to target various fluids such as metal paste, powder, and liquid crystal. As a typical example of the fluid ejecting apparatus, there is an ink jet recording apparatus provided with the ink jet recording head for image recording as described above. However, the present invention is an example of another fluid ejecting apparatus such as a liquid crystal display. Device with color material ejection head used for color filter production, device with electrode material (conductive paste) ejection head used for electrode formation such as organic EL display, surface emitting display (FED), etc., used for biochip production The present invention can be applied to various fluid ejecting apparatuses such as an apparatus having a bio-organic matter ejecting head and an apparatus having a sample ejecting head as a precision pipette.

1 is a schematic external view of a recording apparatus according to an embodiment of the present invention. It is a figure which shows the flow-path structure of an ink supply apparatus. FIG. 3 is a diagram illustrating an arrangement state of recording heads. It is a functional block diagram which shows the system configuration | structure of the said recording device. It is a figure which shows the structure of an injection failure detection means. It is a figure explaining the effect | action of the said injection failure detection means. It is a figure explaining the outline | summary of the injection failure detection method. It is a flowchart explaining an injection failure detection process. It is a flowchart explaining a unit detection process. It is a figure explaining the modification of an injection failure detection means.

Explanation of symbols

1 base, 2 base, 3 supply unit, 4 printing area, 5 take-up unit, 6 control panel, 7 ink cartridge, 7BK black ink cartridge, 7C cyan ink cartridge, 7M magenta ink cartridge, 7Y yellow ink cartridge, 7LC light cyan ink Cartridge, 7LM light magenta ink cartridge, 7G green ink cartridge, 7OR orange ink cartridge, 8 recording head, 9 carriage, 10 guide member, 11 flushing box, 12 waste liquid tank, 13 suction pump, 14 capping device, 15 cap, 16 cartridge Holder, 17 Ink supply device, 18 Pressure pump, 19 Pressure sensor, 20 Air release valve, 21 Air supply tube, 22 Ink supply tube 23, 23 sub tank, 24 case, 25 ink pack, 25a ink discharge port, 26 carriage motor, 27 nozzle, 28 laser light source, 29 detector, 30 detection recording medium, 31 detection pattern, 32 optical reader, 33 nozzle substrate , 44 Host computer, 45 driver, 46 print control means, 47 ejection failure detection means, 48 head drive means, 49 pump control means, 50 cleaning command switch, 51 treatment selection means, 52 carriage control means, 53 notification means, 54 cleaning Control means, 74 inspection area, 75 voltage application circuit, 76 voltage detection circuit, 77 ink absorber, 77a upper absorber, 77b lower absorber, 78 electrode member, 80 integration circuit, 81 inverting amplification circuit, 82 A / D Conversion circuit

Claims (18)

An ejection head that ejects fluid from the nozzles by the input of an ejection signal, an ejection failure detection unit that detects ejection failure nozzles of the ejection head, and a control unit that controls the ejection head and the ejection failure detection unit,
The above control means classifies all nozzles into a plurality of nozzle groups and performs unit detection operation for detecting ejection failure nozzles with each nozzle group as one unit between each unit detection operation every time a predetermined detection timing arrives. The fluid ejecting apparatus is characterized in that control is performed so that the timing is shifted at a time.   The fluid ejecting apparatus according to claim 1, wherein the control unit performs control so as to execute an ejecting operation for ejecting a fluid to a predetermined target between one unit detecting operation and the next unit detecting operation.   The control means controls to execute unit detection operations sequentially by interrupting an injection operation every time a predetermined detection timing arrives while executing a series of fluid injection commands for a predetermined target. The fluid ejecting apparatus according to the description. A carriage that moves the ejection head between an ejection area that ejects fluid to a predetermined target and a detection area that is provided outside the ejection area and performs a unit detection operation;
While the control unit moves the ejection head to the ejection area and performs a series of fluid ejections on a predetermined target, the control means moves the ejection head to the detection area and performs unit detection operation every time a predetermined detection timing arrives. The fluid ejecting apparatus according to claim 3, wherein the fluid ejecting apparatus is controlled to execute.   5. The fluid ejecting apparatus according to claim 1, wherein the control unit performs control so that the unit detection operation is performed by classifying the nozzles as one unit nozzle group for each one or a plurality of nozzle rows. .   5. The control unit according to claim 1, wherein the control unit performs control so that the unit detection operation is performed by classifying the nozzles as one unit nozzle group for each kind of fluid to be ejected. Fluid ejection device.   5. The fluid ejecting apparatus according to claim 1, wherein the control unit performs control so as to classify one unit nozzle group according to a nozzle position in a nozzle row and execute a unit detection operation. 6.   8. The fluid ejection according to claim 7, wherein the control means performs control so as to execute a unit detection operation by classifying one unit of nozzle group according to whether the nozzle position is an odd-numbered nozzle position or an even-numbered nozzle position in the nozzle array. apparatus. It has a plurality of the above jet heads,
5. The fluid ejecting apparatus according to claim 1, wherein the control unit performs control so that the unit detection operation is performed by classifying nozzles as one unit nozzle group for each of one or a plurality of ejecting heads. .   The fluid ejection device according to any one of claims 1 to 9, wherein the predetermined detection timing is a timing at which injection to a target of a predetermined unit is completed.   The fluid ejection device according to any one of claims 1 to 9, wherein the predetermined detection timing is a timing at which ejection by ejection data of a predetermined unit is completed.   The fluid ejecting apparatus according to claim 1, wherein the predetermined detection timing is a timing at which ejection by a predetermined unit of the ejection job is completed.   The fluid ejection device according to any one of claims 1 to 9, wherein the predetermined detection timing is a timing at which injection of a predetermined number of injection shots is completed.   The fluid ejecting apparatus according to claim 1, wherein the predetermined detection timing is a timing at which ejection of a predetermined time is completed.   15. The control unit according to any one of claims 1 to 14, wherein when executing a series of fluid ejection commands for a predetermined target, control is performed so as not to perform a unit detection operation for a nozzle group corresponding to a fluid that is not used. The fluid ejecting apparatus according to the item.   The control means automatically executes the recovery operation by the recovery means for recovering the injection characteristics of the defective injection nozzle when the number of defective injection nozzles and the distribution state are unacceptable when the defective injection nozzle is found. The fluid ejecting apparatus according to claim 1, wherein the fluid ejecting apparatus is controlled as described above.   The control means does not perform the recovery operation by the recovery means for recovering the injection characteristics of the defective injection nozzle when the defective injection nozzle is found and the number of defective injection nozzles and the distribution state are within a predetermined allowable range. The fluid ejecting apparatus according to any one of claims 1 to 15, wherein the fluid ejecting apparatus is controlled so as to be notified.   The control means controls to start the next injection operation as it is when an injection failure nozzle is found and the number and state of the injection failure nozzles are within an allowable range in which the influence on the injection quality is small. The fluid ejecting apparatus according to any one of?

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