JP2008062609A - Inkjet recording device and restoration control method of platen absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To minimize the amount of ink used by inhibiting the deposition of ink on a platen absorber, and to reduce the running cost. <P>SOLUTION: The volume of ink required to inhibit the deposition is defined individually for each of inks which are easily deposited on a platen absorber. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a serial scanning type ink jet recording apparatus that performs a recording operation by scanning a recording head in a direction intersecting with a conveyance direction of a recording medium, and particularly includes the area so as not to generate a blank in an area following an edge of the recording medium. The present invention relates to an ink jet recording apparatus that ejects ink onto a platen absorber by protruding the edge of a recording medium during a borderless recording operation in which recording is performed, and a recovery operation control method for the platen absorber.

  In recent years, printers that eject ink from nozzles of a print head have become widespread as output devices for computers, and printers that can print images up to the edge of printing paper have also been realized. As one method for realizing such printing, a method has been proposed in which ink ejected outside the edge of the printing paper is absorbed by an ink absorber. The ink absorber is provided in a groove portion of the platen portion that supports the printing paper during printing, and prevents the platen portion from being soiled by the ink ejected to the outside of the end of the printing paper.

  However, in an ink jet recording apparatus that uses ink that is easy to deposit and has low penetrability as compared with conventional inks, the ink that accumulates easily deposits on the surface of the platen absorber, and the deposit is the backside of the recording medium. There are problems such as fouling, recording medium conveyance failure, deposit overflow, and contact with the ejection port forming surface of the recording head.

  As an apparatus having means for solving such a problem, there has been proposed an ink jet recording apparatus that suppresses the deposition by applying an ink that suppresses the deposition to the ink that is easily deposited deposited on the platen absorber.

For example, Patent Document 1 and Patent Document 2 can be cited as conventional examples.
JP 2001-301201 JP Japanese Patent Laid-Open No. 2002-086760

  The conventional method counts the number of easily deposited inks ejected to the platen absorber for all the easily deposited ink groups by dot count, and when the count exceeds a certain value, a certain amount of deposition suppression ink is counted. Discharging to the platen absorber. This method does not take into account the ease of depositing each ink that tends to deposit, and uses a deposition suppressing ink more than necessary.

  An object of the present invention is to reduce the use amount of the deposition suppressing ink and reduce the running cost.

  In order to achieve the above object, the present invention has the following configuration.

  That is, an apparatus for performing recording by ejecting ink from the recording means to the recording medium while scanning the recording means for ejecting ink in a direction intersecting with the conveyance direction of the recording medium. In an ink jet recording apparatus that includes an absorber and is capable of performing marginless recording in which recording is performed including the area so as not to generate a margin in an area that follows the edge of the recording medium, the recording means is agglomerated and deposited. A first discharge unit that discharges the first ink group that is easy to discharge and a second ink discharge unit that discharges the second ink group that suppresses aggregation and accumulation of the first ink group are arranged along the scanning direction. When the borderless recording is performed, the first ink group ejected onto the platen absorber when the first ink group protrudes from the edge of the recording medium and is ejected onto the platen absorber. The second ink group is ejected onto the platen absorber by an amount obtained by multiplying each ink amount of the ink group by a specified value determined for each ink of the first ink group. .

  Further, the second aspect of the present invention divides the platen absorber into several areas in the first aspect, and determines the discharge amount of the second ink group to the platen absorber for each area. It discharges to each area of the platen absorber.

  The third mode of the present invention is characterized in that, in the first mode or the second mode, the deposition-inhibiting ink is ejected to and around the ink ejection position where the platen absorber easily deposits.

  According to the present invention, it is possible to minimize the use amount of the deposition suppressing ink for suppressing the deposition of the ink that is easily deposited.

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

(First embodiment)
FIG. 1 is a perspective view showing an ink jet recording apparatus applied in the present embodiment in a state where an exterior portion is removed and an internal mechanism is exposed. The recording apparatus main body in the present embodiment includes a paper feed unit, a paper transport unit, a paper discharge unit, a carriage unit, a cleaning unit, a platen unit, an exterior unit, and the like. Hereinafter, the configuration and operation of each unit will be described in order.

  The paper feed unit has a mechanism for separating the recording media stacked on the pressure plate M2010 one by one and feeding them to the platen M3040 side. The paper transport unit includes a roller pair including a transport roller M3060 that sandwiches and transports the fed recording medium toward a recording area by the recording head, and a pinch roller M3070 provided opposite to the transport roller M3060, and a drive source for the transport roller M3060. A transfer motor E0002 and the like. The paper discharge unit includes a paper discharge roller M3110 for discharging the recording medium from the recording area and a plurality of spur rollers cooperating therewith.

  The carriage unit includes a carriage M4000 for mounting a recording head, and the carriage M4000 is supported by a guide shaft M4020 and a guide rail M1011. The guide shaft M4020 is in the recording medium conveyance direction (Y direction). The carriage M4000 is guided and supported so as to reciprocate and scan in the perpendicular direction. The carriage M4000 is driven via a timing belt M4041 by a carriage motor E0001 attached to the chassis M1010.

  When an image is formed on the recording medium in the above configuration, the recording position in the row direction of the image is positioned by conveying a recording medium by a pair of rollers including a conveyance roller M3060 and a pinch roller M3070. For the position in the column direction of the image, the carriage M4000 is moved in the direction perpendicular to the transport direction by the carriage motor E0001, and the recording head is arranged at the target image position. The positioned recording head ejects ink to the recording medium in accordance with a signal from the electric control board E0014. Although the detailed configuration of the recording head will be described later, in the recording arrangement of this embodiment, the recording medium is moved in the row direction by the main scanning in which the carriage M4000 moves in the column direction while performing the recording by the recording head, and the conveyance roller M3060. An image is formed on a recording medium by alternately repeating the transported sub-scanning.

  In marginless recording, which forms an image up to the edge of the recording medium, in order to prevent margins from being generated in the recording medium, in this embodiment, the ink is ejected from the edge of the recording medium by 3 mm and ejected by the platen absorber M3040. Absorbs ink.

Next, the configuration of the head cartridge H1000 applied in the present embodiment will be described with reference to FIG. The head cartridge H1000 in this embodiment has a recording head H1001, means for mounting the ink tank H1900, and means for supplying ink from the ink tank H1900 to the recording head, and is detachable from the carriage M4000. Mounted on. FIG. 2 shows a state where the ink tank H1900 is attached to the head cartridge H1000.

  The recording apparatus of the present embodiment forms an image with eight colors of ink, and therefore, an eight-color ink tank H1900 having an independent configuration is prepared. These ink tanks are detachable from the head cartridge H1000. The ink tank H1900 can be attached and detached while the head cartridge H1000 is mounted on the carriage M4000.

  FIG. 3 shows the arrangement of the nozzle groups of the recording head in the first embodiment of the present invention. The nozzle rows corresponding to the different ink colors are composed of 768 nozzles arranged at an interval of 1200 dpi (dot / inch; reference value) in the recording medium conveyance direction, and each ejects approximately 2 picoliters of ink droplets. A recording head unit 1302 that characterizes high-speed full-color recording is an ejection unit (first ejection unit) that ejects pigments Yellow, Magenta, Cyan ink, and pigment Black, which are three primary color materials for reproducing full color by subtractive color mixing. 1304, 1305, 1306 and 1312. Each discharge unit is arranged in a direction different from the scanning direction (X direction) of the recording head H1001 (for example, the recording medium conveyance direction (Y direction) intersecting substantially perpendicularly), and has two nozzle rows for one color ink. is doing. In addition, between these two nozzle rows, the nozzles are arranged so as to be shifted in the transport direction by ½ pitch. In the drawing, the ejection units (two rows) shown on the left side of the ejection unit 1312 are unused ejection units in the present embodiment.

  On the other hand, the recording head unit 1303 that enables high-quality recording discharges discharge light cyan ink (also referred to as light cyan ink) and light magenta ink (also referred to as light magenta ink), respectively, for enhancing the gradation of the output image. Sections 1307 and 1309, an ejection section 1308 for ejecting dye black ink for increasing the contrast of the output image, and an ejection section 1310 for ejecting dye gray ink for enhancing the gradation of the output image are provided. Further, in the present embodiment, in order to make it possible to reproduce a color gamut that cannot be reproduced only with the three primary colors of Cyan, Magenta, and Yellow, a discharge unit 1311 (second discharge unit) that discharges special color ink is also provided. It is. In the recording head unit 1303 as well, each of the ink discharge units 1307 to 1311 for each color ink is configured by two nozzle rows as in the recording head unit 1302.

Specified value that multiplies each easy-to-deposit amount of ink to determine the amount of deposition-inhibiting ink. Accumulation of ink on the platen absorber means that an aggregate of ink with a height of 0.1 mm or more is generated from the surface of the platen absorber. To do. Experiments have shown that there is a difference in the ease of depositing depending on the type of ink that is easy to deposit. For example, when the four types of inks Cyan, Magenta, Yellow, and Black inks that are easily deposited in this example are compared, the deposition when the same amount of ink is ejected to the platen absorber is Black>Cyan>Magenta> Most in order of Yellow. For this reason, a large amount of ink that suppresses deposition is determined for pigment black ink with a large amount of accumulation, and a small amount of ink that suppresses accumulation is determined for a pigment Yellow with a small amount of accumulation. The amount of ink that suppresses accumulation is determined according to the degree of accumulation. In this embodiment, in order to calculate the accumulation suppression ink amount, each easy ink accumulation amount 1 is multiplied by the specified values of Black = 2, Cyan = 0.5, Magenta = 0.2, Yellow = 0.1, and each easy accumulation ink. The amount of accumulation-inhibiting ink for suppressing accumulation of ink is determined. In this embodiment, the dye black ink and the dye gray ink are used as the deposition suppression ink.

  By defining a prescribed value for determining the amount of accumulation suppression ink for each ink that easily accumulates, the amount of accumulation suppression ink used can be minimized. The discharge operation sequence of the deposition suppressing ink with respect to the platen absorber in consideration of these will be described below.

Discharge Operation Sequence for Platen Absorber A deposition suppression ink discharge amount calculation method and timing for discharging deposition suppression ink according to the first embodiment of the present invention will be described.

  FIG. 4 shows a flowchart of the “deposition suppression ink discharge amount calculation sequence”. The operation for calculating the ejection amount of the deposition suppression ink onto the platen absorber will be described with reference to this flowchart.

  When the printing operation starts in Step 4-1, first, in Step 4-2, information on whether or not the image to be formed is “marginless recording” is acquired. Determine if there is. When it is determined that “marginless recording” is not performed, image recording is performed in the order of Step 4-4 and Step 4-5, and the printing operation ends. On the other hand, if it is determined that “marginless recording” is to be performed, the information on the type of the recording medium is acquired in Step 4-6, and then the amount of deposition suppression ink ejected to the platen absorber is calculated. The calculation method of the deposition suppression ink is as follows.

  First, in Step 4-7, the number of ejections of ink 1 that tends to deposit onto the entire platen absorber is dot-counted, and the ejection amount per dot is determined. Calculate the amount discharged to the body. In this embodiment, since four inks that are easily deposited are used, the same calculation is performed up to ink 4 that is easily deposited. Subsequently, in Step 4-8, the accumulation suppression ink amount for suppressing the accumulation of the ink 1 that easily deposits is multiplied by the specified value of the ink 1 that is easily deposited to the amount of the ink 1 that is easily deposited deposited on the platen absorber. Ask. In this embodiment, four inks that are easy to deposit are used, so that each ink up to ink 4 that is easy to deposit is determined using the prescribed value determined for each ink that is easy to deposit, as in the calculation for ink 1 that is easy to deposit. The amount of accumulation suppression ink for the ink that is likely to accumulate is calculated.

  Next, in Step 4-9, the amount of each accumulation suppression ink ejected to the platen absorber during image recording is calculated from the number of ejections by dot count. Using the above calculated values, platen absorption after image recording is performed by subtracting the sum of the amount of accumulation suppression ink discharged to the platen absorber at the time of image recording from the total amount of accumulation suppression ink amount up to ink 4 that easily deposits in Step 4-10. The amount of deposition-inhibiting ink that is driven into the body is determined.

  The suppression effect of the deposition suppression ink is the same whether it is ejected to the platen absorber during image recording or after the image recording, so the amount of deposition suppression ink that has been struck during image recording is subtracted from the sum.

  Specifically, inks 1 to 4 that are easy to deposit are pigments Cyan, Magenta, Yellow, and Black, and assuming that 10 picoliters of each is ejected to the platen absorber, the amount of deposition suppression ink is the pigment Cyan ink using the above specified value. 10 x 0.5 = 5 picoliters, 10 x 0.2 = 2 picoliters for Pigment Magenta ink, 10 x 0.1 = 1 picoliter for Pigment Yellow ink, 10 x 2 = 20 for Pigment Black ink Calculated as picoliters. When the amount of ink for suppressing deposition discharged to the platen absorber during image recording, in this embodiment, the amount of dye black ink and dye gray ink is 5 picoliters at a time, the amount of ink for suppressing deposition deposited on the platen absorber after image recording is (5 + 2 + 1 + 20)-(5 + 5) = 18 picoliters. The calculated deposition suppression ink discharge amount to the platen absorber is distributed to the dye suppression ink dye black ink and dye gray ink.

  The thus-determined deposition suppression ink ejection amount to the platen absorber is ejected evenly over the entire ejection position to the platen absorber of ink that is likely to accumulate after image recording.

  FIG. 5 is a flowchart showing the timing at which the deposition suppressing ink is discharged to the platen absorber. After the accumulation suppression ink discharge amount calculation sequence in Step 5-2 is completed, the sum of the accumulation suppression ink discharge amounts calculated by this sequence in Step 5-3 is held in a storage unit (not shown). Next, in Step 5-4, it is determined whether or not the ejection amount of the deposition inhibiting ink held in the storage means (not shown) has exceeded a set threshold value. Only when the amount exceeds the limit, the amount of deposition suppression ink held in the storage means (not shown) is discharged to the platen absorber in the order of Step 5-5 and Step 5-6, and the amount of deposition suppression ink is reset to zero. If the threshold is not exceeded, nothing is done. Subsequently, it is determined whether or not there is a next print command within the specific time set in Step 5-7 or Step 5-9. If NO in Step 5-7, the printing operation ends in Step 5-8. If NO in Step 5-9, the ejection amount of the deposition suppression ink held in the storage means (not shown) is ejected to the platen absorber in the order of Step 5-10, Step 5-11 and Step 5-12, and the deposition suppression ink amount is set to 0. To complete the printing operation. If there is a next print command, return to Step 5-1 to start the printing operation and repeat the above sequence.

  As described above, there is an effect of minimizing the use amount of the deposition-inhibiting ink by providing a prescribed value for obtaining the accumulation-inhibiting ink amount for each ink that is easily deposited.

(Second embodiment)
Next, a method for dividing the platen absorber according to the second embodiment of the present invention into several areas and calculating the ejection amount of the deposition suppressing ink in each area will be described.

  FIG. 6 shows a flowchart of the “deposition suppression ink discharge amount calculation sequence” of the second embodiment of the present invention. The sequence from Step 6-1 to Step 6-6 is the same as in the first embodiment. The calculation of the deposition suppression ink discharge amount to the platen absorber is as follows.

  The platen absorber is divided into areas as shown in FIG. First, in Step 6-7, the discharge amount to each area of the platen absorber is calculated from the dot count for the ink 1 that is easily deposited. In the present embodiment, four inks that are easily deposited are used, so the same calculation is performed up to ink 4 that is easily deposited. Next, in Step 6-8, the accumulation suppression ink amount to be ejected for the easily deposited ink 1 ejected in each area is calculated by multiplying the amount of the easily deposited ink 1 by the specified value of the easily deposited ink 1. . In the present embodiment, four inks that are easily deposited are used, so that the deposition suppressing ink that is ejected to each area with respect to each ink that easily deposits up to the ink 4 that easily deposits in the same manner as the calculation for the ink 1 that easily deposits. Calculate the quantity. The specified values of the inks that are easily deposited are the same as those in the first embodiment. Subsequently, in Step 6-9, the ejection amount of each accumulation suppressing ink ejected to each area of the platen portion during image recording is calculated from the dot count. In Step 6-10, for each area, subtract the sum of the accumulation suppression ink amount ejected to the area at the time of image recording from the sum of the accumulation suppression ink amounts up to the easily deposited ink 4 ejected to the area, and then to each area after image recording. The amount of accumulation suppressing ink to be discharged is determined. A specific example is the same as in the first embodiment.

  In this way, the amount of ink for suppressing accumulation in each area of the platen absorber determined in this way is discharged to the discharge position to the platen absorber so that the ink easily deposits in each area of the platen absorber after image recording. .

  The timing of discharging the deposition suppression ink to each area of the platen absorber is the same as that in the first embodiment.

  As described above, a specified value for determining the amount of deposition suppression ink is provided for each ink that is likely to accumulate, and the platen absorber can be divided into several areas so that the required amount of deposition suppression ink can be ejected to the required location. There is an effect that the ink deposition on the surface of the platen absorber can be efficiently suppressed while the amount of the deposition suppressing ink used is minimized.

(Third embodiment)
Next, a description will be given of a third embodiment of the present invention, which is a method of ejecting the deposition-suppressing ink to the platen absorber and the periphery of the ink that is easily deposited.

  The method for calculating the amount of ink for suppressing deposition ejected to the platen absorber is the same as in the first or second embodiment. When the deposition suppression ink is ejected to the platen absorber, it is ejected to and near the ejection position of the ink that is easily deposited. The timing at which the deposition suppression ink is ejected to the platen absorber is the same as in the first embodiment.

  As described above, by depositing ink that tends to deposit on the platen absorber and its surroundings, ink that accumulates easily spreads over a wide area of the platen absorber, thus effectively suppressing ink accumulation. There is an effect that can be done.

1 is a perspective view showing an internal mechanism of an ink jet recording apparatus applied in an embodiment of the present invention. FIG. 3 is a perspective view showing a state where an ink tank is attached to a head cartridge applied to an embodiment of the present invention. FIG. 3 is a diagram illustrating an arrangement configuration of nozzle groups of a recording head according to an embodiment of the invention. FIG. 5 is a flowchart for determining the amount of accumulation suppression ink ejected to the platen portion in the first embodiment of the present invention. FIG. 3 is a flowchart showing timing for discharging the deposition suppression ink to the platen portion in the first embodiment of the present invention. FIG. 10 is a flow chart for determining the amount of accumulation suppression ink ejected to each area of the platen portion in the second embodiment of the present invention. FIG. 10 is a diagram showing an area for dot counting of a platen portion in a second embodiment of the present invention.

Explanation of symbols

M3040 Platen absorber
M5011 Ink receiver
E0001 Carriage motor
H1000 8-color head cartridge
H1001 Recording head
H1900 ink tank
1302 Recording head
1303 Recording head
1304 to 1312 Discharge part

Claims (7)

An apparatus for performing recording by ejecting ink from the recording means to the recording medium while scanning the recording means for ejecting ink in a direction intersecting the conveyance direction of the recording medium, and a platen absorber in a groove of the platen portion In an ink jet recording apparatus capable of performing borderless recording in which recording is performed including the area so as not to generate a blank in an area following the edge of the recording medium.
In the borderless recording, when the first ink group protrudes from the edge of the recording medium and is ejected onto the platen absorber, the ink amount of the first ink group ejected onto the platen absorber An ink jet recording apparatus, wherein a discharge amount of the second ink group is determined according to the discharge amount, and the discharge amount of the ink of the second ink group is discharged onto the platen absorber. The recording means includes a first ejection unit that ejects a first ink group that easily aggregates and accumulates, and a second ink ejection that ejects a second ink group that suppresses aggregation and accumulation of the first ink group. Are sequentially arranged along the scanning direction,
During the borderless recording, each of the first ink groups discharged onto the platen absorber when the first ink group protrudes from the edge of the recording medium and is discharged onto the platen absorber. The amount of the second ink group obtained by multiplying the amount of ink by a specified value determined for each ink of the first ink group is ejected onto the platen absorber. The ink jet recording apparatus described.   The platen absorber is divided into a plurality of areas, and the second ink group having an amount obtained by multiplying each ink amount of the first ink group ejected in each area by a specified value is ejected onto the platen absorber. The inkjet recording apparatus according to claim 2, wherein:   The inkjet recording apparatus according to claim 2, wherein the second ink group is ejected to an ejection position of the first ink group ejected on the platen absorber.   The inkjet recording apparatus according to claim 2, wherein the second ink group is ejected to and around the ejection position of the first ink group ejected on the platen absorber.   When the amount of ink in the second ink group, which is an amount obtained by multiplying the predetermined value determined for each ink in the first ink group, exceeds a threshold value determined after image recording, the image recording Immediately after, the ejection operation of the second ink group is performed, and when the threshold value is not exceeded, the ejection operation of the second ink group is performed after a lapse of a predetermined time after the image recording. The inkjet recording apparatus according to claim 2.   The inkjet recording apparatus according to claim 6, wherein when there is a print command within a predetermined time after the image recording, the print command is given priority over the ejection operation of the second ink group.

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