JP2009166271A - Inkjet printer, inkjet printer control method and control program - Google Patents

Abstract

A printing waiting time is reduced.
SOLUTION: Nozzle inspection means (S106) for outputting ejection information as to whether or not printing recording liquid has been ejected from nozzles of a print head for each of a plurality of nozzles, cleaning means (S116) for cleaning the print head, A first print data creation means (S122) for creating print data using all nozzles; a second print data creation means (S120) for creating print data using only nozzles that can be ejected based on ejection information; Nozzle determination means (S108) for determining whether or not there is a nozzle that cannot be discharged in the discharge information by executing nozzle inspection means, and a criterion for determining whether or not the number of nozzles that cannot be discharged is a predetermined reference number or more A number determination unit (S110), a cleaning selection unit (S112) for selecting whether or not to execute the cleaning unit, and whether or not the print quality is important. Inkjet printer including a-option to print quality selection means (S114), the.
[Selection] Figure 5

Description

  The present invention relates to an inkjet printer equipped with a nozzle clogging detection function, an inkjet printer control method, and a control program.

  Conventionally, as an ink jet printer, an ink droplet ejected from a nozzle of a print head is charged, and the charged ink droplet is ejected to a portion (inspection area) that receives the ink droplet facing the nozzle, which is caused by the ejection of the ink droplet. A device that inspects whether or not an ink droplet is actually ejected from a nozzle by detecting an induced voltage is known (see, for example, Patent Document 1). Further, a light beam is formed in a direction intersecting the ejection direction in which the ink droplet is ejected from the nozzle of the print head, and the ink droplet is ejected from the nozzle by detecting whether the ink droplet ejected from the nozzle blocks the light beam. There is also known an apparatus that inspects whether or not the liquid is actually discharged (see, for example, Patent Document 2).

  However, in the conventional method, when a nozzle that cannot be ejected is found, the print head is cleaned, so that the cleaning execution time is awaited without obtaining a print result. In addition, there is a problem that a case where only the layout result needs to be known, such as draft printing, is similarly waited, and ink droplets are consumed for cleaning.

  In order to solve this problem, for example, Patent Document 3 describes a method of generating print data using only ejectable nozzles excluding nozzles that cannot be ejected.

JP 59-120464 A JP 2005-35309 A JP 2003-11338 A

  However, the conventional method has a problem that the printing time becomes long when there are few nozzles that can be ejected even when the printing quality is not important.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
An ink jet printer that performs printing on a print medium using a print head having a plurality of nozzles for discharging a print recording liquid, and driving means for driving the print head so that the print recording liquid is discharged from the nozzles Discharge information indicating whether or not the print recording liquid is discharged from the nozzles of the print head by driving the print head from above the inspection area provided at a position where the print medium is not disposed. Nozzle inspection means for outputting a plurality of nozzles, cleaning means for cleaning the print head, first print data creation means for creating print data using all the nozzles, and ejection based on the ejection information Second print data creation means for creating print data using only the nozzles, and before executing the nozzle inspection means. Nozzle determination means for determining whether or not there is a nozzle that cannot be discharged in the discharge information, reference number determination means for determining whether or not the number of nozzles that cannot be discharged is a predetermined reference number or more, and the cleaning A cleaning selection unit that selects whether or not to execute the unit, and a print quality selection unit that selects whether or not to place importance on the print quality, and the nozzle determination unit determines that there is a nozzle that cannot be ejected. If it is determined, the reference number determination unit is executed, and if it is determined that there is no nozzle that cannot be ejected, the first print data generation unit is executed, and the reference number determination unit is equal to or greater than the predetermined reference number. If it is determined that the cleaning selection means is executed, the cleaning means, the nozzle inspection means, and the second print data creation means are determined. The cleaning selection means executes the cleaning means, but if selected, executes the cleaning means, the nozzle inspection means, and the second print data creation means, but does not execute the cleaning means. If so, the print quality selection means is executed, and the print quality selection means emphasizes print quality, but if selected, the second print data creation means is executed and the print quality is not considered important is selected. In the case of the ink jet printer, the first print data creating means is executed.

  According to this configuration, if the print quality is not important, the time required for cleaning the print head can be saved even when the number of nozzles that cannot be ejected is larger than the predetermined reference number. Printing time can be shortened by printing using the nozzles.

[Application Example 2]
An ink jet printer control method for printing on a print medium using a print head having a plurality of nozzles for discharging a print recording liquid, wherein the print head is driven so that the print recording liquid is discharged from the nozzles And a discharge step of whether or not the print recording liquid is discharged from the nozzles of the print head by driving the print head from above the inspection area provided at a position where the print medium is not disposed. A nozzle inspection step for outputting information for each of the plurality of nozzles, a cleaning step for cleaning the print head, a first print data creation step for creating print data using all the nozzles, and the ejection information A second print data creation step for creating print data using only the nozzles that can be discharged based on the nozzle; and the nozzle inspection step A nozzle determination step for determining whether or not there are nozzles that cannot be discharged in the discharge information, and a reference number determination step for determining whether or not the number of nozzles that cannot be discharged is a predetermined reference number or more, A cleaning selection step for selecting whether or not to execute the cleaning step, and a print quality selection step for selecting whether or not to place importance on print quality, wherein the nozzle determination step includes the nozzles that cannot be ejected. If it is determined, the reference number determination step is executed. If it is determined that there is no nozzle that cannot be ejected, the first print data creation step is executed. The reference number determination step is equal to or greater than the predetermined reference number. When it is determined that the cleaning selection process is performed, the cleaning selection process is executed. In the cleaning selection step, if the cleaning step is executed, the cleaning step, the nozzle inspection step, and the second print data creation step are executed, and the cleaning step is executed. If NO is selected, the print quality selection step is executed, and the print quality selection step emphasizes print quality, but if selected, the second print data creation step is executed, and the print quality is not emphasized. When the is selected, the first print data creation step is executed.

  According to this configuration, if the print quality is not important, the time required for cleaning the print head can be saved even when the number of nozzles that cannot be ejected is larger than the predetermined reference number. Printing time can be shortened by printing using the nozzles.

[Application Example 3]
A control program for an inkjet printer that performs printing on a print medium using a print head having a plurality of nozzles for discharging a print recording liquid, and driving the print head so that the print recording liquid is discharged from the nozzles And a discharge step that determines whether or not the print recording liquid has been discharged from the nozzles of the print head by driving the print head from above the inspection area provided at a position where the print medium is not disposed. A nozzle inspection step for outputting information for each of the plurality of nozzles, a cleaning step for cleaning the print head, a first print data creation step for creating print data using all the nozzles, and the ejection information Second print data creation that creates print data using only the nozzles that can discharge based on And a nozzle determination step for executing the nozzle inspection step to determine whether or not there is a nozzle that cannot be discharged in the discharge information, and whether or not the number of nozzles that cannot be discharged is a predetermined reference number or more. A reference number determination step for determining, a cleaning selection step for selecting whether or not to execute the cleaning step, and a print quality selection step for selecting whether or not to place importance on print quality, the nozzle determination step comprising: If it is determined that there is a nozzle that cannot be ejected, the reference number determination step is executed. If it is determined that there is no nozzle that cannot be discharged, the first print data creation step is performed, and the reference number determination step is performed. Is determined to be equal to or greater than the predetermined reference number, the cleaning selection step is performed, and it is determined that the predetermined reference number is not equal to or greater than the predetermined reference number. If the cleaning step, the nozzle inspection step, and the second print data creation step are executed, and the cleaning selection step executes the cleaning step, the cleaning step and the nozzle inspection step are performed. And the second print data creation step, and when the selection not to execute the cleaning step is performed, the print quality selection step is executed, and the print quality selection step is selected to place importance on print quality In this case, the second print data creation step is executed, and if the print quality is not important, the first print data creation step is executed if selected.

  According to this configuration, if the print quality is not important, the time required for cleaning the print head can be saved even when the number of nozzles that cannot be ejected is larger than the predetermined reference number. Printing time can be shortened by printing using the nozzles.

  Hereinafter, embodiments of an inkjet printer will be described with reference to the drawings.

(First embodiment)
<Inkjet printer configuration>
First, the configuration of the inkjet printer according to the first embodiment will be described with reference to FIG. FIG. 1 is a perspective view showing the configuration of the ink jet printer according to the first embodiment.

  As shown in FIG. 1, the inkjet printer 20 includes a printer mechanism 21 including a print head 24 and a carriage 22, a paper feed mechanism 31 including a paper feed roller 35 driven by a drive motor 33, and a platen 44. Nozzle inspection which is a nozzle inspection means which inspects whether ink droplets are normally ejected from the print head 24 and which is formed near the left end on the platen 44 and outputs ejection information. An apparatus 50 and a controller 70 that controls the entire inkjet printer 20 are provided.

  The printer mechanism 21 includes a carriage 22 that reciprocates left and right along a guide 28 by a carriage belt 32 and a carriage motor 34, and mounted on the carriage 22, yellow (Y), magenta (M), cyan (C), and black (K) ink cartridges 26 that individually store inks that are printing recording liquids of the respective colors, a print head 24 that applies pressure to each ink supplied from each ink cartridge 26, and pressure applied by the print head 24 A nozzle 23 serving as an ejection hole for ejecting ink droplets onto the recording paper S, which is a printing medium, and a platen 44 serving as a support member that supports the recording paper S being printed are provided. In this embodiment, pigment ink is used as the ink. A linear encoder 25 that detects the position of the carriage 22 is disposed in the vicinity of the carriage 22, and the position of the carriage 22 can be managed using the linear encoder 25. Although not shown, the ink cartridge 26 is an ink used for printing such as cyan (C), magenta (M), yellow (Y), and black (K) containing dye or pigment as a colorant in water as a solvent. Are respectively detachably mounted on the carriage 22.

<Configuration of print head>
Next, the configuration of the print head will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the print head.

  As shown in FIG. 2, the print head 24 is provided with a nozzle row 43 in which a plurality of nozzles 23 that eject inks of cyan (C), magenta (M), yellow (Y), and black (K) are arranged. It has been. Here, all nozzles are collectively referred to as nozzles 23, all nozzle rows are collectively referred to as nozzle rows 43, cyan nozzles and nozzle rows are nozzles 23C and 43C, magenta nozzles and nozzle rows are nozzles 23M. The nozzle row 43M, the yellow nozzle and the nozzle row are referred to as a nozzle 23Y and a nozzle row 43Y, and the black nozzle and the nozzle row are referred to as a nozzle 23K and a nozzle row 43K. Hereinafter, description will be given using the nozzle 23K. In the print head 24, 180 nozzles 23 </ b> K are arranged along the conveyance direction of the recording paper S to form a nozzle row 43 </ b> K. The nozzle 23K is provided with a piezoelectric element 48 as a driving element (driving means) for ejecting ink droplets. By applying a voltage to the piezoelectric element 48, the piezoelectric element 48 is deformed to pressurize the ink. It discharges from the nozzle 23K.

  The print head 24 includes a plurality of mask circuits 47 provided corresponding to the plurality of piezoelectric elements 48 that drive the respective nozzles 23K. The original signal ODRV and the print signal PRTn generated by the controller 70 are input to the mask circuit 47. Note that n at the end of the print signal PRTn is a number for specifying the nozzles included in the nozzle row. In this embodiment, since the nozzle row is composed of 180 nozzles, n is any number from 1 to 180. It becomes a numerical value. This original signal ODRV has a first pulse P1, a second pulse P2, a third pulse P3, as shown in the lower part of FIG. 2, within a period of one pixel (within the time during which the carriage 22 crosses the interval of one pixel). It consists of three drive waveforms. In the present embodiment, the original signal ODRV having these three drive waveforms as a repeating unit is referred to as one segment. When the original signal ODRV and the print signal PRTn are input, the mask circuit 47 transmits a necessary pulse among the first pulse P1, the second pulse P2, and the third pulse P3 based on these signals to the drive signal DRVn (n Is the same as n of the print signal PRTn) and is output toward the piezoelectric element 48 of the nozzle 23K.

  Specifically, when only the first pulse P1 is output from the mask circuit 47 to the piezoelectric element 48, one shot of ink droplet is ejected from the nozzle 23K, and a small size dot (small dot) is formed on the recording paper S. It is formed. When the first pulse P1 and the second pulse P2 are output to the piezoelectric element 48, two shots of ink droplets are ejected from the nozzle 23K, and medium-sized dots (medium dots) are formed on the recording paper S. The When the first pulse P1, the second pulse P2, and the third pulse P3 are output to the piezoelectric element 48, three shots of ink droplets are ejected from the nozzle 23K, and a large size dot (large size) is formed on the recording paper S. Dot) is formed. Thus, in the inkjet printer 20, it is possible to form dots of three types of sizes by adjusting the amount of ink ejected in one pixel section. The other color nozzles 23C, 23M, and 23Y and the nozzle rows 43C, 43M, and 43Y are the same as the nozzle 23K and the nozzle row 43K. Here, the print head 24 employs a method in which the piezoelectric element 48 is deformed to pressurize the ink, but the ink is generated by bubbles generated by heating the ink by applying a voltage to a heating resistor (for example, a heater). You may employ | adopt the system which pressurizes.

<Configuration of paper feed mechanism>
Next, the configuration of the paper feed mechanism will be described with reference to FIG. FIG. 3 is a schematic diagram showing the configuration of the paper feed mechanism.

  As shown in FIG. 3, the recording paper insertion slot 18 into which the recording paper S placed on the paper feeding tray 14 is inserted, and the paper feeding that supplies the recording paper S placed on the paper feeding tray 14 to the print head 24. A roller 36, a paper feed roller 35 that conveys the recording paper S and roll paper to the print head 24, and a paper discharge roller 37 that discharges the printed recording paper S are provided. The paper feed roller 36, paper feed roller 35, and paper discharge roller 37 are driven by a drive motor 33 (see FIG. 1) via a gear mechanism (not shown). A plurality of recording sheets S are prevented from being fed at a time by the rotational driving force of the sheet feeding roller 36 and the frictional resistance of a separation pad (not shown). In FIG. 1, the conveyance direction of the recording sheet S is a direction from the back side toward the front side, and the movement direction of the carriage 22 that moves together with the print head 24 is a direction (main scanning direction) orthogonal to the conveyance direction of the recording sheet S. .

<Configuration of nozzle inspection device>
Next, the configuration of the nozzle inspection apparatus will be described with reference to FIG. FIG. 4 is a block diagram showing the configuration of the nozzle inspection apparatus.

  As shown in FIG. 4, the nozzle inspection device 50 includes an inspection box 51 in which ink droplets flying from the nozzles 23 of the print head 24 can land, and a predetermined distance from the print head 24 provided in the inspection box 51. Provided, a voltage application circuit 53 for applying a voltage between the inspection area 52 and the print head 24, and a voltage detection circuit 54 for detecting the voltage of the inspection area 52. The inspection box 51 is a housing that is provided at a position off the left side from the printable area of the platen 44 and is a substantially rectangular parallelepiped with an upper portion opened.

  The inspection area 52 is provided in the inspection box 51, and an upper ink absorber 55 on which ink droplets directly land, and a lower ink that absorbs ink droplets that have been transmitted downward after landing on the upper ink absorber 55. The absorber 56 and a mesh-like electrode member 57 disposed between the upper ink absorber 55 and the lower ink absorber 56 are configured. The upper ink absorber 55 is made of a conductive sponge so as to have the same potential as the electrode member 57, and the surface thereof is an inspection region 52. This sponge is highly permeable so that the landed ink droplets can move down quickly, and here, an ester urethane sponge (trade name: Everlite SK-E, manufactured by Bridgestone Corporation) is used. Yes. The lower ink absorber 56 has higher ink retention than the upper ink absorber 55 and is made of a nonwoven fabric such as felt. Here, the nonwoven fabric (trade names: Kinocloth, Oji Kinocross Co., Ltd.) Made).

  The electrode member 57 is formed as a grid-like mesh made of a metal made of stainless steel (for example, SUS). For this reason, the ink once absorbed by the upper ink absorber 55 is absorbed and held by the lower ink absorber 56 through the gap between the grid-like electrode members 57. The voltage application circuit 53 is electrically connected via a DC power source (for example, 400 V), a resistance element (for example, 1 MΩ), and a switch SW so that the electrode member 57 is a positive electrode and the print head 24 is a negative electrode. . Here, since the electrode member 57 is in contact with the conductive upper ink absorber 55, the surface of the upper ink absorber 55, that is, the inspection region 52 is also at the same potential as the electrode member 57.

  The voltage detection circuit 54 is connected so as to detect the voltage of the electrode member 57 equated with the voltage of the inspection region 52, integrates and outputs the voltage signal of the electrode member 57, and the integration circuit 54a. An inverting amplification circuit 54b that inverts and amplifies the output signal and outputs the signal, and an A / D conversion circuit 54c that A / D converts the signal output from the inverting amplification circuit 54b and outputs the signal as ejection information to the controller. ing. The integration circuit 54a outputs a large voltage change by integrating the voltage change due to the flight / landing of a plurality of ink droplets since the voltage change due to the flight / landing of one ink droplet is small. The inverting amplifier circuit 54b inverts the sign of the voltage change and amplifies and outputs the signal output from the integrating circuit at a predetermined amplification factor determined by the circuit configuration. The A / D conversion circuit 54 c converts the analog signal output from the inverting amplification circuit 54 b into a digital signal and outputs the digital signal to the controller 70.

  As shown in FIG. 1, the cap device 40 is used when sealing the nozzles 23 in order to prevent the nozzles 23 from being dried during a printing pause or the like. The cap device 40 is operated so as to cover the nozzle formation surface of the print head 24 when the print head 24 moves together with the carriage 22 to the right end (referred to as a home position). The cap device 40 is connected to a suction pump (not shown). For example, when nozzle clogging is detected by the nozzle inspection device 50, the negative pressure of the suction pump is applied to the nozzle forming surface of the print head 24 sealed by the cap device 40 as necessary. The ink clogged from 23 is sucked and discharged. Note that the waste ink discharged and collected is stored in a waste liquid tank (not shown).

  As shown in FIG. 1, the controller 70 is configured as a microprocessor centered on the CPU 72, and includes a ROM 73 that stores various processing programs, a RAM 74 that temporarily stores data and stores data, A flash memory 75 that can write and erase data, an interface (I / F) 79 that exchanges information with an external device, and an input / output port (not shown) are provided. The ROM 73 stores processing programs for a main routine and a nozzle inspection routine, which are control means, and a print processing routine, which will be described later. The RAM 74 is provided with a print buffer area, and print data sent from the user PC 10 via the I / F 79 is stored in this print buffer area. In addition to the voltage signal output from the voltage detection circuit 54 of the nozzle inspection device 50 and the position signal of the carriage 22 from the linear encoder 25 being input to the controller 70 via an input port (not shown), the user PC 10 A print job or the like output from is input via the I / F 79. Further, from the controller 70, a control signal to the print head 24 (including the mask circuit 47 and the piezoelectric element 48), a control signal to the drive motor 33, a drive signal to the carriage motor 34, and an operation control signal to the cap device 40. Are output via an output port (not shown), and print status information to the user PC is output via the I / F 79.

<Operation of inkjet printer>
Next, the operation of the ink jet printer will be described with reference to FIG. FIG. 5 is a flowchart showing the operation of the ink jet printer. This routine is executed by the CPU 72 at predetermined timings (for example, every several milliseconds) after the power of the inkjet printer 20 is turned on.

  When this routine is started, the CPU 72 first determines in step S100 whether or not there is a print job waiting for printing. Since the print job received from the user PC 10 is stored in the print buffer area formed in the RAM 74 and becomes a print job waiting to be printed, when the print job is received, it can be printed immediately as well as during printing. Even so, the print job is waiting for printing. If there is no print job waiting for printing in step S100, the main routine is terminated. If there is a print job, the process proceeds to step S102.

  In step S102, the image data stored in the print buffer area is read.

  Next, in step S104, it is determined whether or not it is the inspection timing for performing the nozzle inspection. If it is the inspection timing, the process proceeds to step S106, and if it is not the inspection timing, the process proceeds to step S122. The inspection timing is determined from the time elapsed since the previous nozzle inspection was performed, the number of print head discharges, the number of printed sheets, and the like.

  Next, in step S106, a nozzle inspection routine is executed.

  Here, the operation of the nozzle inspection routine will be described with reference to FIG. FIG. 8 is a flowchart showing the operation of the nozzle inspection routine.

  When the nozzle inspection routine is started, first, in step S300, the CPU 72 turns on the switch SW of the voltage application circuit 53 to generate a predetermined potential difference between the inspection region 52 and the print head 24, and the current inspection. The position, that is, the position of the inspection region 52 that ejects ink from the nozzle 23 is acquired. Here, since the solid matter contained in the ink may be deposited on the surface of the inspection area 52 due to the ejection of the ink, the inspection position is set to change every time the nozzle inspection routine is executed.

  FIG. 9 is an explanatory diagram of the inspection position in the nozzle inspection process. In FIG. 9, a plurality of inspection positions p1, p2, p3, and p4 are set. In one nozzle inspection routine, each nozzle row 43 has a variation in the detected value of the dielectric voltage due to the difference in the inspection position. The ink is set to be ejected to the same inspection position. For example, when the current nozzle inspection is performed at the inspection position p1, the nozzle row 43Y is first positioned so as to face the inspection position p1, and ink droplets are ejected from the nozzles 23Y included in the nozzle row 43Y. Next, the nozzle row 43M is positioned so as to face the inspection position p1, and ink droplets are ejected from the nozzles 23M included in the nozzle row 43M. Thereafter, the nozzle rows 43C and 43K are similarly tested at the inspection position p1. Ink droplets are ejected from the nozzles 23C and 23K. Further, the ink is ejected to a position different from the current inspection position at the next inspection position so that the solid content of the ink is not excessively accumulated only at a certain inspection position. For example, when the current nozzle inspection is performed at the inspection position p1, the next nozzle inspection is performed at the inspection position p2.

  Returning to the description of the nozzle inspection routine of FIG. 8, in step S310, after acquiring the current inspection position in step S300, the CPU 72 drives the carriage motor 34 and the nozzles to be inspected in the nozzle row 43 of the print head 24. The carriage 22 is moved so that the row 43 faces the current inspection position.

  Next, in step S320, an ink droplet charged from the nozzle 23 is ejected through the mask circuit 47 and the piezoelectric element 48 (see FIG. 2) of one nozzle 23 in the nozzle row 43 to be inspected.

  Here, a change in voltage in the electrode member 57 when the charged ink droplets fly from the nozzles 23 of the print head 24 and reach the inspection region 52 including the upper ink absorber 55 will be described with reference to FIG. FIG. 10 is an explanatory diagram of the principle that an induced voltage is generated by electrostatic induction. As shown in FIG. 10A, the ink droplet before flying from the nozzle 23 by the print head 24 is negatively charged by the voltage application circuit 53. In addition, since the print head 24 and the inspection area 52 are arranged at a distance and a predetermined potential difference is generated between them, a predetermined electric field strength (= potential difference / distance) is generated between them. Yes. For this reason, as shown in FIG. 10B, as the negatively charged ink droplets fly from the nozzle 23 and approach the upper ink absorber 55, the surface of the upper ink absorber 55 is positively applied by electrostatic induction. The charge increases. As a result, the voltage between the print head 24 and the electrode member 57 becomes higher than the initial voltage value due to the induced voltage generated by electrostatic induction.

  Thereafter, as shown in FIG. 10C, when the negatively charged ink droplet reaches the upper ink absorber 55, the positive charge of the upper ink absorber 55 is neutralized by the negative charge of the ink droplet. As a result, the voltage between the print head 24 and the electrode member 57 is lower than the initial voltage value. Thereafter, the voltage between the print head 24 and the electrode member 57 returns to the applied voltage value. The amplitude of the output signal at this time depends not only on the distance from the print head 24 to the upper ink absorber 55 (inspection region 52), but also on the presence or size of flying ink droplets. For this reason, when the nozzle 23 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 becomes smaller than the normal time. The presence or absence of clogging can be determined.

  In the present embodiment, even if the ink droplet has a predetermined size, the amplitude of the output signal from the ink droplet for one shot is extremely small. Therefore, one segment of the first to third pulses P1, P2, representing the drive waveform. By performing the operation of outputting all of P3 eight times, ink droplets for 24 shots are ejected. As a result, the output signal becomes an integrated value of ink droplets for 24 shots, and thus a sufficiently large output waveform can be obtained from the voltage detection circuit 54. Note that the direction of the amplitude of the signal output from the voltage detection circuit 54 is reversed because it passes through the inverting amplification circuit 54b.

  Returning to the description of the nozzle inspection routine of FIG. 8, in step S330, the ink charged from the nozzle 23 via the mask circuit 47 or the piezoelectric element 48 of one nozzle 23 in the nozzle row 43 to be inspected in this way. After ejecting the droplet, the CPU 72 determines whether the amplitude of the signal output from the voltage detection circuit 54, that is, the output level is equal to or higher than the threshold value Vthr. If the threshold value is equal to or higher than the threshold value Vthr, the CPU 72 proceeds to step S350. In this case, the process proceeds to step S340. As shown in FIG. 11, the threshold value Vthr exceeds the output level when ink for 24 shots is normally ejected, and exceeds noise due to noise or the like when ink for 24 shots is not ejected normally. It is a value determined empirically so that nothing happens.

  Next, in step S340, it is considered that an abnormality such as clogging has occurred in the current nozzle 23, and discharge information (for example, information indicating which nozzle row in which nozzle row) that identifies the nozzle 23 is stored in the RAM 74 in a predetermined manner. Store in the area.

  Next, in step S350, the CPU 72 determines whether all nozzles 23 included in the nozzle row 43 currently being inspected have been inspected, and inspecting all nozzles 23 included in the nozzle row 43 currently being inspected. When the inspection is performed, the process proceeds to step S370, and when all the nozzles 23 included in the nozzle row 43 currently inspected are not inspected, the process proceeds to step S360.

  Next, in step S360, when there is an uninspected nozzle 23 in the nozzle row currently being inspected, the nozzle 23 to be inspected is updated to an uninspected nozzle, and then the processes in and after step S320 are performed again.

  On the other hand, in step S370, it is determined whether or not all nozzle arrays 43 included in the print head 24 have been inspected. If all nozzle arrays 43 have been inspected, the process proceeds to step S390, and all nozzle arrays 43 are inspected. If the inspection is not performed for 43, the process proceeds to step S380.

  Next, in step S380, the nozzle row 43 to be inspected is updated to an uninspected nozzle row 43, and then the processes in and after step S310 are performed again.

  On the other hand, in step S390, the switch SW of the voltage application circuit 53 is turned off, and this nozzle inspection routine ends.

  By executing this routine, if there is a nozzle 23 having an abnormality among all the nozzles 23 arranged in the print head 24 in the predetermined area of the RAM 74, information for specifying the nozzle 23 is discharge information. If there is no nozzle 23 in which an abnormality has occurred, nothing is stored.

  Returning to the description of the main routine of FIG. 5, after executing the nozzle inspection routine (step S106) described above, the CPU 72 detects that an abnormality has occurred among all the nozzles 23 arranged in the print head 24 in step S108, which is nozzle determination means. Whether there is a nozzle 23 that has occurred is determined based on the ejection information stored in a predetermined area of the RAM 74. If there is a nozzle 23 that has an abnormality, the process proceeds to step S110, where an abnormality has occurred. If no nozzle 23 is present, the process proceeds to step S122.

  Next, in step S110, which is a reference number determination means, the number of nozzles that cannot be discharged is calculated from the discharge information stored in a predetermined area of the RAM 74, and whether or not the number of nozzles that cannot be discharged is equal to or greater than a predetermined reference number. If it is greater than or equal to the predetermined reference number, the process proceeds to step S112. If not greater than the predetermined reference number, the process proceeds to step S116. The predetermined reference number may be set to 10% of the total number of nozzles on the print head 24, for example. Further, the predetermined reference number may be changed based on the print quality, the type of recording paper, and the like.

  Next, in step S112, which is a cleaning selection unit, based on the selection of whether or not to execute cleaning, the process proceeds to step S116 if cleaning is performed, and the process proceeds to step S114 if cleaning is not performed. The selection of whether or not to execute cleaning may be selected by the user as an option of a print setting screen instructing execution of printing from the user PC 10, for example, or may be set based on the print quality, the type of recording paper, and the like. Also good.

  Next, in step S114, which is a print quality selection unit, based on the selection of whether or not to place importance on print quality, the process proceeds to step S120 if the print quality is important, or to step S122 if the print quality is not important. To do. The selection as to whether or not importance is placed on the print quality may be selected by the user as an option of a print setting screen for instructing execution of printing from the user PC 10, or may be set based on the print quality or the type of recording paper. May be.

  Next, in step S116 which is a cleaning unit, the print head 24 is cleaned. Specifically, the carriage motor 34 is driven to move the carriage 22 until the print head 24 comes to the home position facing the cap device 40, and the cap device 40 is operated so that the cap device 40 forms the nozzles of the print head 24. After covering the surface, the negative pressure of a suction pump (not shown) is applied to the nozzle forming surface to suck and discharge the clogged ink from the nozzle 23.

  Next, in step S118, the nozzles that cannot be ejected are recovered by executing the cleaning in step S116, and the number of nozzles that cannot be ejected has changed, so the nozzle inspection routine is executed again.

  Next, in step S120 as the second print data creation means, print data is created from the image data using only the nozzles that can be ejected based on the ejection information stored in the predetermined area of the RAM 74. If the number of nozzles that can be ejected is small, the printing speed becomes slow.

  On the other hand, in step S122, which is the first print data creation means, print data is created from image data using all nozzles.

  Next, in step S124, the CPU 72 executes a print processing routine.

  FIG. 7 is a flowchart showing the operation of this print processing routine.

  When the print processing routine is started, first, in step S200, the CPU 72 executes a paper feed process. The paper feed process is a process of conveying the recording paper S placed on the paper feed tray 14 to the paper feed roller 35 by driving the drive motor 33 to rotate the paper feed roller 36 (see FIG. 3).

  Next, in step S202, the CPU 72 drives the carriage motor 34 to eject the ink from the print head 24 while moving the carriage 22 leftward in FIG. 1 from the home position or the like, and executes forward printing based on the print data.

  Next, in step S206, the CPU 72 determines whether or not there is print data to be printed on the recording sheet S that is currently being printed. If there is print data, the process proceeds to step S208. The process proceeds to S218.

  Next, in step S208, a conveyance process for rotating the paper feed roller 35 and conveying the recording paper S by a predetermined amount is executed.

  Next, in step S210, ink is ejected from the print head 24 while the carriage 22 is moved rightward in FIG. 1 by driving the carriage motor 34, and backward printing is executed based on the print data.

  Next, in step S214, the CPU 72 determines whether there is print data to be printed on the recording sheet S that is currently being printed. If there is print data, the process proceeds to step S216. The process proceeds to S218.

  Next, in step S216, the paper feed roller 35 is rotationally driven to execute a transport process for transporting the recording paper S by a predetermined amount, and the process proceeds to step S202.

  In step S218, the CPU 72 executes a paper discharge process for discharging the recording paper S. The paper discharge process is a process of rotating the paper discharge roller 37 to discharge the recording paper S to the paper discharge tray. After step S218, this print processing routine is terminated.

  According to the present embodiment described above, the following effects can be obtained.

  In this embodiment, if printing quality is not important, the time required for cleaning the print head can be saved even when the number of nozzles that cannot be ejected is larger than a predetermined reference number. Printing time can be shortened by printing using nozzles.

  The embodiments of the ink jet printer have been described above. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the spirit of the invention. Hereinafter, a modification will be described.

  (Modification 1) Modification 1 of the ink jet printer will be described. In the first embodiment, the operation as shown in FIG. 5 has been described, but the order of step S110 and step S112 may be interchanged as shown in FIG.

1 is a perspective view illustrating a configuration of an inkjet printer according to a first embodiment. FIG. 3 is a block diagram illustrating a configuration of a print head. Schematic which shows the structure of a paper feed mechanism. The block diagram which shows the structure of a nozzle test | inspection apparatus. The flowchart which shows operation | movement of an inkjet printer. 9 is a flowchart showing the operation of an ink jet printer according to Modification 1. 6 is a flowchart showing an operation of a print processing routine. The flowchart which shows operation | movement of a nozzle test | inspection routine. Explanatory drawing of the test | inspection position in a nozzle test process. Explanatory drawing of the principle which an induced voltage produces by electrostatic induction. Explanatory drawing which shows an example of threshold value Vthr.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 14 ... Paper feed tray, 18 ... Recording paper insertion port, 20 ... Inkjet printer, 21 ... Printer mechanism, 22 ... Carriage, 23, 23Y, 23M, 23C, 23K ... Nozzle, 24 ... Print head, 25 ... Linear encoder, 26 ... Ink cartridge, 28 ... Guide, 31 ... Paper feed mechanism, 32 ... Carriage belt, 33 ... Drive motor, 34 ... Carriage motor, 35 ... Paper feed roller, 36 ... Paper feed roller, 37 ... Paper discharge roller, 40 ... Cap device, 43, 43Y, 43M, 43C, 43K ... Nozzle array, 44 ... Platen, 47 ... Mask circuit, 48 ... Piezoelectric element, 50 ... Nozzle inspection device, 51 ... Inspection box, 52 ... Inspection region, 53 ... Voltage application Circuit 54 ... Voltage detection circuit 54a ... Integration circuit 54b ... Inverting amplifier circuit 54c ... A / D conversion circuit 55 ... Upper side Ink absorber 56 ... lower ink absorber, 57 ... electrode member, 70 ... controller, 72 ... CPU, 73 ... ROM, 74 ... RAM, 75 ... flash memory, 79 ... interface (I / F).

Claims (3)

An inkjet printer that performs printing on a print medium using a print head having a plurality of nozzles that discharge a print recording liquid,
Driving means for driving the print head so that the printing recording liquid is discharged from the nozzle;
The print head is driven by the driving means from above the inspection area provided at a position where the print medium is not disposed, and discharge information indicating whether or not the print recording liquid is discharged from the nozzles of the print head Nozzle inspection means for outputting each nozzle;
Cleaning means for cleaning the print head;
First print data creating means for creating print data using all the nozzles;
Second print data creation means for creating print data using only the nozzles capable of ejection based on the ejection information;
Nozzle determination means for executing the nozzle inspection means and determining whether or not there is a nozzle that cannot be discharged in the discharge information;
Reference number determination means for determining whether or not the number of nozzles that cannot be ejected is equal to or greater than a predetermined reference number;
Cleaning selection means for selecting whether to execute the cleaning means;
Print quality selection means for selecting whether or not to place importance on print quality;
Including
The nozzle determination unit executes the reference number determination unit when it is determined that there is a nozzle that cannot be discharged, and executes the first print data generation unit when it is determined that there is no nozzle that cannot be discharged.
The reference number determination unit executes the cleaning selection unit when it is determined that the reference number is equal to or greater than the predetermined reference number, and the cleaning number, the nozzle inspection unit, and the like when it is determined that the reference number is not equal to or greater than the predetermined reference number. Executing the second print data creating means;
When the cleaning selection unit executes the cleaning unit, the cleaning unit, the nozzle inspection unit, and the second print data generation unit are executed, and when the cleaning unit is not executed, the selection is performed. Executes the print quality selection means,
The print quality selection unit executes the second print data creation unit when importance is placed on print quality, and executes the first print data creation unit when selection is made not to place importance on print quality. ,
An inkjet printer characterized by the above. A control method for an ink jet printer that performs printing on a print medium using a print head having a plurality of nozzles for discharging a print recording liquid,
A driving step of driving the print head so that the printing recording liquid is discharged from the nozzle;
The print head is driven by the driving process from above an inspection area provided at a position where the print medium is not disposed, and discharge information indicating whether the print recording liquid has been discharged from the nozzles of the print head is displayed as the plurality of print information. Nozzle inspection process that outputs for each nozzle;
A cleaning step of cleaning the print head;
A first print data creation step for creating print data using all the nozzles;
A second print data creation step for creating print data using only the nozzles capable of ejection based on the ejection information;
A nozzle determination step of determining whether there is a nozzle that cannot be discharged in the discharge information by performing the nozzle inspection step;
A reference number determination step of determining whether or not the number of nozzles that cannot be ejected is a predetermined reference number or more;
A cleaning selection step for selecting whether to perform the cleaning step;
A print quality selection process for selecting whether or not to place importance on print quality;
Including
The nozzle determining step performs the reference number determining step when it is determined that there is a nozzle that cannot be ejected, and executes the first print data creating step when it is determined that there is no nozzle that cannot be ejected,
In the reference number determination step, the cleaning selection step is executed when it is determined that the reference number is equal to or greater than the predetermined reference number, and when it is determined that the reference number is not equal to or greater than the predetermined reference number, the cleaning step, the nozzle inspection step, Executing a second print data creation step;
In the cleaning selection step, when the cleaning step is executed, the cleaning step, the nozzle inspection step, and the second print data creation step are executed when the cleaning step is selected, and the cleaning step is not executed. Performs the print quality selection step,
The print quality selection step executes the second print data creation step when importance is placed on the print quality, but executes the first print data creation step when the focus is not placed on the print quality. ,
An ink jet printer control method. A control program for an ink jet printer that performs printing on a print medium using a print head having a plurality of nozzles for discharging a print recording liquid,
A driving step of driving the print head so that the printing recording liquid is discharged from the nozzle;
The print head is driven by the driving step from above an inspection area provided at a position where the print medium is not disposed, and discharge information indicating whether or not the print recording liquid is discharged from the nozzles of the print head Nozzle inspection step that outputs for each nozzle;
A cleaning step for cleaning the print head;
A first print data creation step for creating print data using all the nozzles;
A second print data creation step for creating print data using only the nozzles capable of ejection based on the ejection information;
A nozzle determination step for performing the nozzle inspection step and determining whether or not there is a nozzle that cannot be discharged in the discharge information;
A reference number determination step for determining whether or not the number of nozzles that cannot be ejected is a predetermined reference number or more;
A cleaning selection step for selecting whether to perform the cleaning step;
A print quality selection step for selecting whether or not to place importance on print quality;
Including
The nozzle determination step performs the reference number determination step when it is determined that there is a nozzle that cannot be ejected, and executes the first print data creation step when it is determined that there is no nozzle that cannot be ejected,
In the reference number determination step, the cleaning selection step is executed when it is determined that the reference number is equal to or greater than the predetermined reference number, and when it is determined that the reference number is not equal to or greater than the predetermined reference number, the cleaning step, the nozzle inspection step, and the Executing a second print data creation step;
In the cleaning selection step, when the execution of the cleaning step is selected, the cleaning step, the nozzle inspection step, and the second print data generation step are executed, and the case where the cleaning step is not executed is selected. Performs the print quality selection step,
The print quality selection step executes the second print data creation step when importance is placed on print quality, but executes the first print data creation step when importance is not placed on print quality. ,
An ink jet printer control program.

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