JP2006272754A - Liquid ejection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recording device, and more broadly a liquid ejection device, which eliminates wasteful microvibration before printing, occurring in a conventional liquid ejection device. <P>SOLUTION: The liquid ejection device comprises a head member having a plurality of nozzle openings arranged in a plurality of rows, a liquid ejection means for ejecting liquid at selected ones of the nozzle openings, a microvibration means for microvibrating the liquid at the nozzle openings at every ejection operation, and a driving starting timing determining means for determining microvibration starting timing of the microvibration means. The microvibration starting timing determining means determines the microvibration starting timing of the microvibration means by paying attention to a relative location of each row of the nozzle openings with respect to a liquid ejectable range. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus that ejects liquid droplets from nozzle openings.

  An ink jet recording apparatus (a type of liquid ejecting apparatus) such as an ink jet printer or an ink jet plotter moves a recording head (head member) along the main scanning direction and also transfers a recording paper (a type of liquid ejected medium) An image (including characters and the like) is recorded on the recording paper by moving along the scanning direction and ejecting ink droplets from the nozzle openings of the recording head in conjunction with the movement. The ink droplets are ejected, for example, by expanding and contracting a pressure generating chamber that communicates with the nozzle opening.

  Incidentally, since the ink is exposed to air at the nozzle opening portion of the recording head, the ink solvent (for example, water) gradually evaporates. The evaporation of the ink solvent increases the ink viscosity at the nozzle opening, thereby deteriorating the image quality of the recorded image. That is, when the ink viscosity of the portion increases, the ejected ink droplets can fly in a direction deviating from the normal direction.

  For this reason, in the ink jet recording apparatus, measures are taken to prevent thickening of the ink in the nozzle opening portion. One countermeasure against this thickening is agitation of ink by slight vibration of the meniscus. Here, the meniscus is the free surface of the ink exposed at the nozzle opening.

  In this agitation of the ink, the meniscus is alternately moved in the ink droplet ejection direction and the drawing direction opposite to the ejection direction so that the ink droplets are not ejected. This movement of the meniscus is also performed by expanding and contracting the pressure generating chamber. By causing the meniscus to vibrate slightly, the ink at the nozzle opening is agitated, so that thickening of the ink is prevented.

  This ink agitation is performed in conjunction with the recording operation. For example, it is performed during the acceleration period immediately after the start of main scanning of the carriage on which the recording head is mounted or during the recording period of one line (that is, during printing). In the agitation during the acceleration period, a fine vibration drive signal for finely vibrating the meniscus is supplied to the recording head to slightly vibrate the meniscus of all the nozzle openings. In the agitation during printing, a fine vibration pulse is generated from an ejection drive signal for ejecting ink droplets, and the generated fine vibration pulse is supplied to the recording head. As a result, the ink is stirred for the nozzle openings that do not eject ink droplets.

Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique for performing fine vibration control based on the recording start position of the recording head and the recording start position for each nozzle opening.
JP 2001-260369 A

  By the way, the meniscus stirring operation during the acceleration period of the recording head is performed simultaneously for all the nozzle openings.

  The present inventor has found that there is a waste in the fine vibration operation due to the simultaneous start of the fine vibration operation for all the nozzle openings simultaneously. Specifically, when the recording head has a plurality of rows of nozzle openings, the inventor adjusts the start timing of the micro-vibration operation according to the relative position of each row of nozzle openings with respect to the liquid ejectable region. However, it has been found that it can be effective in suppressing energy consumption and shortening printing time by reducing fine vibration time.

  The present invention has been made to solve such problems, and eliminates the waste of the previous pre-printing micro-vibration operation, thereby enabling the ink-jet recording capable of suppressing energy consumption and shortening the printing time. The object is to provide an apparatus, broadly a liquid ejecting apparatus.

  The present invention relates to a head member having a plurality of nozzle openings arranged in a plurality of rows, a liquid ejecting means for ejecting a liquid in the nozzle opening portion for each selected nozzle opening, and finely vibrating the liquid in the nozzle opening portion. And a fine vibration start timing determining means for determining a fine vibration start timing of the fine vibration means, the fine vibration start timing determining means for each row of the nozzle openings with respect to the liquid ejectable region. The liquid ejecting apparatus is characterized in that the fine vibration start timing of the fine vibration means is determined in consideration of the relative position.

  According to the present invention, the micro-vibration start timing determining means determines the micro-vibration start timing of the micro-vibration means in consideration of the relative relationship between the liquid ejectable region and the arrangement of the nozzle openings for each column, and thus the micro vibration start timing is determined. It is possible to suppress the drive time of the means to the minimum necessary. Thereby, suppression of energy consumption is achieved.

  Preferably, the liquid ejecting apparatus includes a support member that supports the liquid ejection medium. Preferably, the liquid ejecting apparatus includes a scanning mechanism that causes the head member to scan relative to the liquid ejected medium. In this case, it is preferable that the liquid ejecting apparatus includes an area storage unit that stores a relative liquid ejectable area of the head member during scanning by the scanning mechanism. Normally, the fine vibration means finely vibrates the liquid in the nozzle opening portion all at once.

  Further, for example, the nozzle openings arranged in each row are nozzle openings that use liquids having the same thickening characteristics. For example, the nozzle openings arranged in each row are nozzle openings that use the same color ink.

  The plurality of nozzle openings arranged in a plurality of rows are set with a predetermined micro-vibration required time or a predetermined number of times of micro-vibration for each row, and the micro-vibration start timing determining means is provided for each row. It is preferable that the fine vibration start timing of the fine vibration means is determined in consideration of a predetermined minute vibration necessary time or a predetermined number of necessary minute vibrations. This makes it possible to set the drive time of the fine vibration means to the minimum necessary for each column.

  Further, it is preferable that the fine vibration start timing determining means determines the fine vibration start timing of the fine vibration means in consideration of the liquid ejection start position for each column. As a result, unnecessary driving of the fine vibration means can be effectively eliminated.

  The scanning mechanism may reciprocate the head member relative to the liquid ejection medium. In this case, a so-called Bi-D type device can be realized.

  Further, the scanning mechanism may determine a moving region of the head member based on a fine vibration start timing of the fine vibration means determined by the fine vibration start timing determination means. In this case, the liquid ejecting apparatus can be driven at a higher speed.

  According to another aspect of the invention, there is provided a liquid ejecting apparatus comprising: a head member having a plurality of nozzle openings arranged in a plurality of rows; and a liquid ejecting unit that ejects the liquid in the nozzle opening portion for each selected nozzle opening. A fine vibration means for finely vibrating the liquid in the nozzle opening portion; and a fine vibration start timing determining means for determining a fine vibration start timing of the fine vibration means. The start timing determining means determines the fine vibration start timing of the fine vibration means in consideration of the relative position of each row of the nozzle openings with respect to the liquid ejectable region. Device.

  The control device or each element means of the control device can be realized by a computer system.

  Further, a program for realizing them in a computer system and a computer-readable recording medium on which the program is recorded are also subject to protection in this case.

  Here, the recording medium includes a network for propagating various signals, in addition to what can be recognized as a single unit such as a flexible disk.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, an ink jet recording apparatus (an example of a liquid ejecting apparatus) according to an embodiment of the present invention is an ink jet printer 1, and a cartridge holder capable of holding a black ink cartridge 2a and a color ink cartridge 2b. A carriage 5 having a section 3 and a recording head 4 (an example of a head member) is provided. The carriage 5 is reciprocated along the main scanning direction by a head scanning mechanism (an example of a scanning mechanism).

  The head scanning mechanism includes a guide member 6 installed in the left-right direction of the housing, a pulse motor 7 provided on one side of the housing, a drive pulley 8 connected to the rotating shaft of the pulse motor 7 and driven to rotate. An idler pulley 9 attached to the other side of the housing, a timing belt 10 spanned between the drive pulley 8 and the idler pulley 9 and coupled to the carriage 5, and a controller for controlling the rotation of the pulse motor 7. 11 (see FIG. 4). Accordingly, by operating the pulse motor 7, the carriage 5, that is, the recording head 4 can be reciprocated in the main scanning direction which is the width direction of the recording paper 12.

  The printer 1 also has a paper feed mechanism that feeds a recording medium (an example of a liquid ejected medium) such as the recording paper 12 in the paper feed direction (sub-scanning direction). This paper feed mechanism includes a paper feed motor 13 and a paper feed roller 14 (an example of a support member). A recording medium such as the recording paper 12 is sequentially sent out in conjunction with the recording operation.

  As shown in FIG. 2, the recording head 4 includes an ink chamber 20 to which ink from the ink cartridge 2a or 2b (see FIG. 1) is supplied, and a nozzle plate in which a plurality of nozzle openings 17 are arranged in the sub-scanning direction. 16 and a plurality of pressure chambers (pressure generation chambers) 22 corresponding to each of the nozzle openings 17 are mainly provided. The pressure chamber 22 expands and contracts due to deformation of the piezoelectric vibrator 21.

  The ink chamber 20 and the pressure chamber 22 communicate with each other via an ink supply port 24 and a supply side communication hole 23. The pressure chamber 22 and the nozzle opening 17 are communicated with each other via the first nozzle communication hole 25 and the second nozzle communication hole 26. That is, a series of ink flow paths from the ink chamber 20 to the nozzle opening 17 through the pressure chamber 22 is formed for each nozzle opening 17.

  The piezoelectric vibrator 21 is a so-called flexural vibration mode piezoelectric vibrator 21. When the piezoelectric vibrator 21 in the flexural vibration mode is used, the piezoelectric vibrator 21 contracts in a direction orthogonal to the electric field by charging and the pressure chamber 22 contracts, and the charged piezoelectric vibrator 21 is discharged. 21 expands in a direction perpendicular to the electric field, and the pressure chamber 22 expands.

  That is, in the recording head 4, the capacity of the corresponding pressure chamber 22 changes as the piezoelectric vibrator 21 is charged / discharged. By utilizing such pressure fluctuations in the pressure chamber 22, ink droplets can be ejected from the nozzle openings 17, or the meniscus (the free surface of the ink exposed at the nozzle openings 17) can be finely vibrated.

  In this case, the recording head 4 is a multicolor recording head capable of recording a plurality of different types of colors. The multicolor recording head includes a plurality of head units, and the type of ink used for each head unit is set.

  The recording head 4 of the present embodiment includes a black head unit capable of ejecting black ink, a cyan head unit capable of ejecting cyan ink, a magenta head unit capable of ejecting magenta ink, and a yellow capable of ejecting yellow ink. A head unit. Each head unit communicates with each ink storage chamber of the corresponding ink cartridge 2a, 2b. Each head unit has the configuration described with reference to FIG. 2, and a nozzle row including a plurality of nozzle openings 17 is divided into black ink and other color inks as shown in FIG. Is formed. The interval between both nozzle rows is, for example, 2.822 mm. This corresponds to about 40 pixels in the case of a printing accuracy of 360 dpi.

  Next, the electrical configuration of the printer 1 will be described. As shown in FIG. 4, the ink jet printer 1 includes a printer controller 30 and a print engine 31.

  The printer controller 30 includes an external interface (external I / F) 32, a RAM 33 that temporarily stores various data, a ROM 34 that stores a control program, a control unit 11 that includes a CPU, a clock, and the like. An oscillation circuit 35 that generates a signal, a drive signal generation circuit 36 that generates a drive signal to be supplied to the recording head 4, and dot pattern data (bitmap data) developed based on the drive signal and print data Etc., and an internal interface (internal I / F) 37 for transmitting the information to the print engine 31.

  The external I / F 32 receives print data including, for example, a character code, a graphic function, image data, and the like from a host computer (not shown). In addition, a busy signal (BUSY) and an acknowledge signal (ACK) are output to the host computer or the like through the external I / F 32.

  The RAM 33 has a reception buffer, an intermediate buffer, an output buffer, and a work memory (not shown). The reception buffer temporarily stores the print data received via the external I / F 32, the intermediate buffer stores the intermediate code data converted by the control unit 11, and the output buffer stores dot pattern data. Remember. Here, the dot pattern data is print data obtained by decoding (translating) intermediate code data (for example, gradation data).

  In addition to a control program (control routine) for performing various data processing, the ROM 34 stores font data, graphic functions, and the like. Further, the ROM 34 also stores setting data for maintenance operation as maintenance information holding means. Further, the ROM 34 stores, as area storage means, an ink dischargeable area E (liquid ejectable area) onto the recording paper 12 of the recording head 4 during main scanning, and a minute vibration area M before and after (left and right). (See FIG. 5). The minute vibration area M is an area for standby or acceleration / deceleration of the recording head 4.

  The drive signal generation circuit 36 generates a main signal generation unit 36a that generates an ejection drive signal used for recording, and a fine vibration signal that slightly vibrates the ink meniscus and stirs the ink in the nozzle opening portion. Selection to output the ejection drive signal or the micro-vibration signal to the internal I / F 37 by inputting the ejection drive signal from the vibration signal generator 36b, the main signal generator 36a, and the micro-vibration signal from the micro-vibration signal generator 36b. Part 36c (see FIG. 4).

  In the present embodiment, a fine vibration start timing determination unit 36d that is a feature of the present invention is connected to the selection unit 36c (see FIG. 4).

  The fine vibration start timing determination unit 36d determines the supply start timing of the fine vibration signal in consideration of the relative position of each nozzle row with respect to the ink dischargeable region E. That is, in the state in which the side of the nozzle row that discharges black ink is close to the ink dischargeable region E, the scanning start time of the recording head 4 (the recording head 4 is in the standby position) is set as the supply start timing of the micro vibration signal. In a state in which the side of the nozzle row that discharges color ink is close to the ink dischargeable region E, the fine vibration signal is supplied when the recording head 4 is slightly delayed from the scanning start time (the recording head 4 is already away from the standby position). The start timing is set.

  Therefore, when reciprocating printing is performed as a Bi-D type ink jet apparatus, the fine vibration start timing at the time of forward movement and the fine vibration start timing at the time of backward movement are different with respect to each scanning start time of reciprocation. It will be.

  In general, black ink tends to increase in viscosity as compared with other color inks. Therefore, the fine vibration of the black ink meniscus needs to be sufficiently performed before ink discharge. Accordingly, in the mode in which the ink dischargeable area E is entered from the nozzle row side that discharges black ink, the scanning of the recording head 4 is started in the same manner as before in order to sufficiently perform fine vibration in the nozzle row that discharges black ink. It is preferable that the time point be the supply start timing of the minute vibration signal. However, in the mode in which the ink dischargeable region E is entered from the side of the nozzle row that discharges the color ink, the slight vibration in the nozzle row that discharges the color ink is not necessary as much as the black ink. Therefore, the timing when the micro-vibration signal is supplied can be set a little later than the time point. This saves energy for unnecessary microvibration control.

  For example, for a nozzle that ejects black ink, before entering the ink ejectable region E, it is preferable that the fine vibration signal is supplied for a time (or number of times) corresponding to 100 pixels. On the other hand, for the nozzles that eject other color inks, it is sufficient that the micro-vibration signal is supplied for a time (or the number of times) corresponding to 50 pixels before entering the ink ejectable region E. In this case, if the standby position (scanning start position) of the recording head 4 is set at a position separated by 100 pixels from the ink dischargeable region E, as described above, the nozzle row that discharges black ink. In the aspect of entering the ink dischargeable region E from the side, it is preferable that the scanning start time of the recording head 4 is set as the supply start timing of the fine vibration signal in order to sufficiently perform the fine vibration in the nozzle row that discharges the black ink. In the mode in which the ink dischargeable region E is entered from the side of the nozzle row that discharges the color ink, the slight vibration in the nozzle row that discharges the color ink is not necessary as much as the black ink. The time point delayed by 40 pixels can be set as the supply start timing of the fine vibration signal (40 = 100−ma). (100-40,50)). In this case, before entering the ink dischargeable area E, fine vibration control is performed for the nozzle row for discharging black ink for 100 pixels and for the nozzle row for discharging color ink for 60 pixels (> 50).

  The drive signal generation circuit 36 can be configured by a logic circuit, or can be configured by a control circuit configured by a CPU, a ROM, a RAM, and the like.

  The control unit 11 performs various controls according to a control program stored in the ROM 34. For example, the print data in the reception buffer is read and the print data is converted into intermediate code data, and the intermediate code data is stored in the intermediate buffer. In addition, the control unit 11 analyzes the intermediate code data read from the intermediate buffer and develops (decodes) it into dot pattern data by referring to the font data and graphic functions stored in the ROM 34. Then, the control unit 11 stores the dot pattern data in the output buffer after performing the necessary decoration processing.

  If dot pattern data for one line that can be recorded by one main scan of the recording head 4 is obtained, the dot pattern data for one line is sequentially transferred from the output buffer to the recording head 4 through the internal I / F 37. Output to the electric drive system 39, the carriage 5 is scanned, and printing for one line is performed. When dot pattern data for one line is output from the output buffer, the developed intermediate code data is erased from the intermediate buffer, and the development process for the next intermediate code data is performed.

  Further, the control unit 11 controls a maintenance operation (recovery operation) performed prior to the recording operation by the recording head 4.

  The print engine 31 includes a paper feed motor 13 as a paper feed mechanism, a pulse motor 7 as a head scanning mechanism, and an electric drive system 39 of the recording head 4.

  Next, the electric drive system 39 of the recording head 4 will be described. As shown in FIG. 4, the electric drive system 39 includes a decoder 50, a shift register circuit 40, a latch circuit 41, a level shifter circuit 42, a switch circuit 43, and the piezoelectric vibrator 21 that are electrically connected in order. These decoder 50, shift register circuit 40, latch circuit 41, level shifter circuit 42, switch circuit 43, and piezoelectric vibrator 21 are provided for each nozzle opening 17 of the recording head 4.

  In this electric drive system 39, when the pulse selection data (SP data) applied to the switch circuit 43 is “1”, the switch circuit 43 is connected and the pulse waveform in the drive signal is directly applied to the piezoelectric vibrator 21. Each piezoelectric vibrator 21 is deformed according to the pulse waveform in the drive signal. On the other hand, when the pulse selection data applied to the switch circuit 43 is “0”, the switch circuit 43 is disconnected and the supply of the drive signal to the piezoelectric vibrator 21 is cut off.

  Thus, a drive signal can be selectively supplied to each piezoelectric vibrator 21 based on the pulse selection data. For this reason, depending on the pulse selection data to be applied, ink droplets can be ejected from the nozzle openings 17 or the meniscus can be slightly vibrated.

  For example, in the example shown in FIG. 6, the ejection drive signal is divided into a first pulse unit 61, a second pulse unit 62, and a third pulse unit 63, and the first pulse unit 61 and the second pulse unit 62 are connected. A small dot drive pulse, a medium dot drive pulse is generated by the second pulse unit 62, a large pulse drive pulse is generated by connecting the second pulse unit 62 and the third pulse unit 63, and the first pulse The unit 61 generates a fine vibration signal during printing.

  Here, the small dot drive pulse is a drive pulse for ejecting ink droplets capable of forming small dots, and the medium dot drive pulse is a drive pulse for ejecting ink droplets capable of forming medium dots, and is driven by large dots. The pulse is a driving pulse for ejecting ink droplets capable of forming large dots, and the fine vibration pulse during printing is a driving pulse for slightly vibrating the meniscus for the nozzle openings 17 that do not eject ink droplets.

  When a fine vibration signal during printing is supplied to the piezoelectric vibrator 21, a meniscus is formed between the discharge side position near the opening edge of the nozzle opening 17 and the drawing side position closer to the pressure generating chamber 22 than the discharge side position. Vibrates slightly. That is, the ink in the nozzle opening is agitated.

  In this example, the print data is composed of 3-bit data 1, D2, and D3. By setting each data to D1 = 1, D2 = 1, and D3 = 0, a small dot drive pulse is generated, and each data is A medium dot drive pulse is generated by setting D1 = 0, D2 = 1, and D3 = 0, and a large dot drive pulse is generated by setting each data to D1 = 0, D2 = 1, and D3 = 1. By setting each data as D1 = 1, D2 = 0, D3 = 0, a fine vibration signal during printing is generated.

  On the other hand, when the ink is stirred by finely vibrating the meniscus by the fine vibration signal from the fine vibration signal generator 36b, “1” is set in the print data of all the nozzle openings 17 during the stirring period. . As a result, a series of micro-vibration driving signals generated by the micro-vibration signal generator 36b is supplied to the piezoelectric vibrator 21 as it is, and the piezoelectric vibrator 21 is deformed, causing the meniscus to vibrate.

  For example, as shown in FIG. 7, the micro-vibration signal can be constituted by a signal in which a plurality of trapezoidal pulses whose potential is switched between the lowest potential and the intermediate potential are connected in series. When such a fine vibration signal is supplied, the pressure generating chamber 21 repeatedly expands and contracts slightly, and the meniscus slightly vibrates between the discharge side position and the drawing side position as in the case of the fine vibration during printing. .

  When supplying the fine vibration signal to the piezoelectric vibrator 21, the print data DV for fine vibration with the data of all the nozzle openings 17 set to "1" is set in the shift register 40, and then the latch signal is applied. Then, the set print data DV is latched to bring the switch 43 into a connected state. In order to stop the supply of the fine vibration signal, the print data DV ′ for stopping fine vibration with the data of all the nozzle openings 17 set to “0” is set in the shift register 40, and the print data DV ′ is latched and switched. 43 is disconnected.

  Next, a recording operation of the printer having the above configuration will be described. In this printer, in order to prevent the ink from being thickened, the meniscus is appropriately vibrated in conjunction with one main scan (one line of recording operation) of the recording head 4. Specifically, the meniscus is slightly vibrated in each state during the acceleration period of the recording head 4 (carriage 5) and during the recording operation.

  As shown in FIG. 8, the control unit 11 first functions as dot pattern data generation means, and generates dot pattern data for one line. That is, the intermediate code data stored in the intermediate buffer is read (S1), and the read intermediate code data is developed into dot pattern data based on the font data and graphic functions of the ROM 34 (S2). Data is stored in the output buffer (S3). This development operation is repeatedly executed until a dot pattern for one line is stored (S4).

  Subsequently, the control unit 11 transfers the developed dot pattern data to the recording head 4 (S5). In response to the transfer of the dot pattern data, an image recording operation for one line is started, and the recording head 8 is main-scanned. In conjunction with this main scanning, fine vibration control is performed in which the meniscus is finely vibrated to stir the ink. Note that the control unit 11 functions as part of the fine vibration means during the execution of the fine vibration control.

  Specifically, the control unit 11 outputs a control signal to the selection unit 36c so that the fine vibration signal from the fine vibration signal generation unit 36c can be supplied to the piezoelectric vibrator 21 (S6). Then, the fine vibration print data DV is set in the shift register 40 and a latch signal is supplied to start supplying the fine vibration signal (S7).

  Here, in this embodiment, in an aspect in which the ink dischargeable region E is entered from the side of the nozzle row that discharges black ink, the recording head 4 has a sufficient amount of fine vibration in the nozzle row that discharges black ink. The fine vibration control is performed with the scanning start time as the supply start timing of the fine vibration signal. On the other hand, in the mode in which the ink dischargeable region E is entered from the side of the nozzle row that discharges the color ink, the slight vibration in the nozzle row that discharges the color ink is not as necessary as the black ink. The micro-vibration control is performed with the time point delayed by 40 pixels from the start timing of supplying the micro-vibration signal.

  Subsequently, the control unit 11 outputs a control signal to the selection unit 36c of the drive signal generation circuit 36 in accordance with the time when the recording head 4 reaches the ink dischargeable area E, and discharges from the main signal generation unit 36a. The drive signal can be supplied (S8). Thereby, an ejection drive signal is supplied, and an image is recorded on the recording paper 12 (S9).

  In this case, as described with reference to FIG. 6, any one of a small dot drive pulse, a medium dot drive pulse, a large dot drive pulse, and a fine vibration signal during printing is generated by each piezoelectric vibrator 21 based on the dot pattern data. To be supplied. By supplying these drive pulses, ink droplets that can form small dots, medium dots, or large dots are ejected from each nozzle opening 17. Further, the nozzle opening 17 that does not eject ink droplets is supplied with a fine vibration signal during printing, whereby the meniscus is vibrated finely, and the ink in the nozzle opening portion is agitated.

  By such control, ink droplets are ejected in a state where the ink viscosity has returned to the normal viscosity due to the slight vibration of the meniscus immediately before. For this reason, the first ink droplet ejected in one row can be accurately caused to fly in a predetermined direction. Therefore, even when the amount of ink droplets to be discharged is reduced and the ink viscosity is likely to increase, it is possible to effectively prevent image quality deterioration at the recording start portion.

  Further, in the present embodiment, for the mode of entering the ink dischargeable region E from the side of the nozzle row that discharges the color ink, the time when the recording head 4 is slightly delayed is set as the supply start timing of the fine vibration signal. be able to. Thereby, unnecessary fine vibration control is avoided and energy and cost can be suppressed.

  Furthermore, the fine vibration start timing may be determined in consideration of the ink discharge start position for each nozzle row.

  For example, in the above-described embodiment, when the ink discharge start position of the nozzle row that discharges black ink and the ink discharge start position of the nozzle row that discharges color ink are both the 21st pixel in the ink dischargeable region E. The fine vibration start timing is set for both the mode of entering the ink dischargeable region E from the nozzle row side for discharging black ink and the mode of entering the ink dischargeable region E from the nozzle row side for discharging color ink. Furthermore, it can be delayed by 20 pixels. The micro-vibration start timing determination unit 36d may determine the supply start timing of the micro-vibration signal as such based on the developed dot pattern data and the like.

If the ink discharge start position of the nozzle row that discharges black ink is different from the ink discharge start position of the nozzle row that discharges color ink, the fine vibration start timing is set for the pixel calculated by the following formula. Can be delayed. That is, with respect to the aspect of entering the ink dischargeable region E from the nozzle row side discharging black ink,
100-max (100-ink discharge start position of black ink,
(50-40)-Color ink ink ejection start position)
For the mode in which the fine vibration start timing can be delayed by the number of pixels, and the ink dischargeable area E is entered from the side of the nozzle row that discharges color ink,
100-max ((100-40) -black ink discharge start position,
50-Ink discharge start position of color ink)
The timing of starting micro-vibration can be delayed by the number of pixels. The micro-vibration start timing determination unit 36d may determine the supply start timing of the micro-vibration signal as such based on the developed dot pattern data and the like.

  In the above embodiment, two nozzle rows are formed of the nozzle row that discharges black ink and the nozzle row that discharges color ink. However, the arrangement of the nozzle rows is not limited to this. For example, a nozzle row including a plurality of nozzle openings 17 may be formed for each ink color (BK, C, M, Y) as shown in FIG.

When the interval between the nozzle rows is also 2.822 mm, which corresponds to 40 pixels, the fine vibration start timing can be delayed by the amount of pixels obtained by the following calculation formula. That is, with respect to the aspect of entering the ink dischargeable region E from the nozzle row side discharging black ink,
100-max (100-ink discharge start position of black ink,
(50-40) -ink discharge start position of cyan ink,
(50-80) -magenta ink discharge start position,
(50-120) -Yellow ink discharge start position)
The timing of starting micro-vibration can be delayed by the number of pixels, and the mode of entering the ink dischargeable region E from the side of the nozzle row that discharges yellow ink is as follows.
100-max ((100-120) -ink discharge start position of black ink,
(50-80) -ink discharge start position of cyan ink,
(50-40)-Ink discharge start position of magenta ink,
50-Ink discharge start position of yellow ink)
The timing of starting micro-vibration can be delayed by the number of pixels. The micro-vibration start timing determination unit 36d may determine the supply start timing of the micro-vibration signal as such based on the developed dot pattern data and the like.

More generally, the number of pixels corresponding to the distance until the nozzle row on the ink dischargeable region E side in the standby position enters the ink dischargeable region E is G, and the distance between the black ink nozzle row and the cyan ink nozzle row The number of pixels corresponding to is g1, the number of pixels corresponding to the interval between the cyan ink nozzle row and the magenta ink nozzle row is g2, and the number of pixels corresponding to the interval between the magenta ink nozzle row and the yellow ink nozzle row is g3, the number of pixels corresponding to the fine vibration control time (or the number of occurrences and the number of times) required for the nozzle that discharges black ink is nb, and the pixel corresponding to the fine vibration control time required for the nozzle that discharges cyan ink The number of pixels is nc, the number of pixels corresponding to the fine vibration control time required for the nozzle that ejects magenta ink is nm, and the fine vibration necessary for the nozzle that ejects yellow ink. When the number of pixels corresponding to the control time is set to ny, only pixels which are determined by the following such formulas can delay the micro-vibrating-starting timing. That is, with respect to the aspect of entering the ink dischargeable region E from the nozzle row side discharging black ink,
G-max (nb—ink discharge start position of black ink,
(Nc-g1) -ink discharge start position of cyan ink,
(Nm-g1-g2) -ink discharge start position of magenta ink,
(Ny-g1-g2-g3) -yellow ink discharge start position)
The timing of starting micro-vibration can be delayed by the number of pixels, and the mode of entering the ink dischargeable region E from the nozzle row side that discharges yellow ink is as follows.
G-max ((nb-g1-g2-g3) -ink discharge start position of black ink,
(Nc-g2-g3) -ink discharge start position of cyan ink,
(Nm-g3) -magenta ink discharge start position,
ny-yellow ink discharge start position)
The timing of starting micro-vibration can be delayed by the number of pixels. The micro-vibration start timing determining unit 36d may determine the supply start timing of the micro-vibration signal as such based on the developed dot pattern data and the like.

  If the acceleration / deceleration of the recording head 4 may be performed within the ink dischargeable area E, the standby position of the recording head 4 is set in accordance with the supply start timing of the fine vibration signal adjusted as described above. It is also possible to change (change the moving area of the recording head 4). That is, the standby position of the recording head 4 is brought closer to the ink dischargeable region E by the pixel corresponding to the “delayed amount” of the supply start timing of the micro-vibration signal described in the embodiment. Is also possible. Thereby, the energy and cost of movement of the recording head 4 can be suppressed, and it is possible to contribute to higher speed driving of the ink jet recording apparatus. In this case, the supply start timing of the minute vibration signal always coincides with the scan start timing of the recording head 4.

  Further, instead of the piezoelectric vibrator 21 in the flexural vibration mode, a so-called longitudinal vibration mode piezoelectric vibrator can be used. The piezoelectric vibrator in the longitudinal vibration mode is a piezoelectric vibrator that expands the pressure chamber by deformation due to charging and contracts the pressure chamber by deformation due to discharge. When the longitudinal vibration mode piezoelectric vibrator is used, the relationship between the rising edge and the falling edge of the drive signal is reversed (positive and negative are reversed) compared to the case of using the flexural vibration mode piezoelectric vibrator 21. .

  In the above embodiment, the liquid ejecting means is described as a piezoelectric vibrator, but is not limited to the piezoelectric vibrator. For example, the present invention can be applied to a case where ink in a pressure generating chamber is ejected from a nozzle opening by a heating element.

  Further, in the embodiment shown in FIG. 3, the nozzle openings for the color inks such as magenta, cyan, and yellow are shown in the same row next to the row of the black ink nozzle openings. Further, the supply start timing of the micro-vibration signal may be changed in the same row in accordance with the difference in the thickening characteristics of the inks of the respective colors in consideration of the relative positions of the nozzle openings for each row. As a result, it is possible to eliminate the waste of the pre-printing fine vibration operation and to reduce energy consumption and shorten the printing time.

  As described above, the printer controller 30 can be configured by a computer system. However, a program for causing the computer system to realize each element and a computer-readable recording medium 201 that records the program are also subject to protection in this case. It is.

  Further, when each of the above elements is realized by a program such as an OS that operates on a computer system, a program including various instructions for controlling the program such as the OS and a recording medium 202 that records the program are also included in the present invention. It is a protection target.

  Here, the recording media 201 and 202 include not only a single unit such as a flexible disk, but also a network for propagating various signals.

  Although the above description has been made with respect to an ink jet recording apparatus, the present invention is intended for a wide range of liquid ejecting apparatuses in general. As an example of the liquid, in addition to ink, glue, nail polish, liquid electrode material, bioorganic liquid, and the like can be used. Furthermore, the present invention can also be applied to an apparatus for manufacturing a color filter in a display body such as a liquid crystal.

1 is a schematic perspective view of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 3 is a diagram for explaining a configuration of a recording head. It is a figure which shows the example of arrangement | positioning of a nozzle row. FIG. 2 is a schematic block diagram illustrating an electrical configuration of a recording head. It is the schematic which shows the relationship between an ink dischargeable area | region and a fine vibration area | region. It is a figure explaining the drive pulse produced | generated based on an ejection drive signal and the said ejection drive signal. It is a figure explaining a fine vibration drive signal. It is a flowchart explaining the recording operation of 1 line. It is a figure which shows the other example of arrangement | positioning of a nozzle row.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer 2a Black ink cartridge 2b Color ink cartridge 3 Cartridge holder part 4 Recording head 5 Carriage 6 Guide member 7 Pulse motor 8 Drive pulley 9 Reverse pulley 10 Timing belt 11 Control part 12 Recording paper 13 Paper feed motor 14 Paper feed roller 16 Nozzle plate 17 Nozzle opening 20 Ink chamber 21 Piezoelectric vibrator 22 Pressure generating chamber 23 Supply side communication hole 24 Ink supply port 25 First nozzle communication hole 26 Second nozzle communication hole 30 Printer controller 31 Print engine 32 External interface 33 RAM
34 ROM
35 Oscillation circuit 36 Drive signal generation circuit 36a Main signal generation unit 36b Fine vibration signal generation unit 36c Selection unit 36d Fine vibration start timing determination unit 37 Internal interface 39 Recording head electric drive system 40 Shift register circuit 41 Latch circuit 42 Level shifter circuit 43 Switch circuit 50 Decorator

Claims (13)

A head member having a plurality of nozzle openings arranged in a plurality of rows;
Liquid ejecting means for ejecting the liquid of the nozzle opening portion for each selected nozzle opening;
A fine vibration means for finely vibrating the liquid in the nozzle opening portion;
A fine vibration start timing determining means for determining a fine vibration start timing of the fine vibration means;
With
The fine vibration start timing determining means determines the fine vibration start timing of the fine vibration means in consideration of the relative position of each row of the nozzle openings with respect to the liquid ejectable region. Liquid ejecting device. 2. The liquid ejecting apparatus according to claim 1, wherein the nozzle openings arranged in each row are nozzle openings using liquids having the same thickening characteristic. The liquid ejecting apparatus according to claim 2, wherein the nozzle openings arranged in each row are nozzle openings that use ink of the same color. In the plurality of nozzle openings arranged in a plurality of rows, a predetermined minute vibration necessary time is set for each row,
2. The micro-vibration start timing determining unit is configured to determine a micro-vibration start timing of the micro-vibration unit in consideration of a predetermined micro-vibration necessary time for each column. 4. The liquid ejecting apparatus according to any one of 3. In the plurality of nozzle openings arranged in a plurality of rows, a predetermined number of times of fine vibration is set for each row,
2. The micro-vibration start timing determining unit is configured to determine a micro-vibration start timing of the micro-vibration unit in consideration of a predetermined number of necessary micro-vibrations for each column. 4. The liquid ejecting apparatus according to any one of 3. 6. The fine vibration start timing determining means determines the fine vibration start timing of the fine vibration means in consideration of the liquid ejection start position for each column. The liquid ejecting apparatus according to any one of the above. The scanning mechanism for scanning the head member relative to the liquid ejection medium is based on the fine vibration start timing of the fine vibration means determined by the fine vibration start timing determining means. The liquid ejecting apparatus according to claim 1, wherein: A head member having a plurality of nozzle openings arranged in a plurality of rows;
Liquid ejecting means for ejecting the liquid of the nozzle opening portion for each selected nozzle opening;
An apparatus for controlling a liquid ejecting apparatus comprising:
A fine vibration means for finely vibrating the liquid in the nozzle opening portion;
A fine vibration start timing determining means for determining a fine vibration start timing of the fine vibration means;
With
The fine vibration start timing determining means determines the fine vibration start timing of the fine vibration means in consideration of the relative position of each row of the nozzle openings with respect to the liquid ejectable region. Control device. In the plurality of nozzle openings arranged in a plurality of rows, a predetermined minute vibration necessary time is set for each row,
9. The micro-vibration start timing determining unit determines a micro-vibration start timing of the micro-vibration unit in consideration of a predetermined micro-vibration necessary time for each column. The control device described. In the plurality of nozzle openings arranged in a plurality of rows, a predetermined number of times of fine vibration is set for each row,
9. The micro-vibration start timing determining unit is configured to determine a micro-vibration start timing of the micro-vibration unit in consideration of a predetermined number of necessary micro-vibrations for each column. The control device described. 11. The fine vibration start timing determining means determines the fine vibration start timing of the fine vibration means in consideration of the liquid ejection start position for each column. The control device described.   A program that is executed by a computer system including at least one computer to cause the computer system to implement the control device according to any one of claims 8 to 11. Instructions for controlling a second program running on a computer system including at least one computer,
A program that is executed by the computer system to control the second program to cause the computer system to implement the control device according to any one of claims 8 to 11.

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