JP2013132851A - Liquid ejecting apparatus and liquid ejecting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a defect in printing due to deposition of a liquid ejected from a nozzle by flushing.SOLUTION: There is provided a liquid ejecting method that uses a liquid ejecting apparatus 1 including a head unit 30 having the nozzle ejecting the liquid, a cylindrical pipe as a liquid reception part which receives the liquid ejected from the nozzle by the flushing by the head, a scraper as a scraping part which abuts against the cylindrical pipe to scrape the liquid off, a flushing unit having a rotary unit 120 including a rotary part rotating the cylindrical pipe, and a controller 60 as a control part controlling the rotary unit 120. The method includes drawing operation for drawing by ejecting the liquid from the nozzle toward a recording medium while relatively moving the head and recording medium, flushing operation for placing the head in flushing operation, and scraping operation for scraping off the liquid which the cylindrical pipe has received by the scraper; and the writing operation is intermittently performed.

Description

  The present invention relates to a liquid ejection apparatus and a liquid ejection method.

A liquid ejecting apparatus that performs maintenance called flushing that forcibly and continuously ejects ink from a nozzle in order to remove foreign matters attached to the nozzle surface is known (for example, Patent Document 1).
In such a liquid ejecting apparatus, when performing flushing, the ink ejected toward the flushing box is absorbed by an absorbent material disposed in the flushing box.

JP-A-8-150722

  However, in the liquid ejection device described in Patent Document 1, when the ink absorbed in the absorbent material is an ink having low re-dissolvability or re-dispersibility, when the ink is dried, the gap of the absorbent material is filled with the dry ink. Therefore, the absorbing material cannot absorb ink. For this reason, the ink discharged toward the flushing box is not absorbed and accumulates on the absorbent material. Then, there is a problem that the accumulated ink may come into contact with the nozzle surface to cause a printing failure.

  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 A liquid ejection apparatus according to this application example includes a head having a nozzle that ejects a liquid, a liquid receiving unit that receives liquid ejected from the nozzle when the head performs flushing, and the liquid receiver. A rotating unit that rotates the rotating unit, a control unit that controls the rotating unit, a scraping unit that scrapes the liquid received by the liquid receiving unit by contacting the rotating liquid receiving unit, It is provided with.

  According to this application example, the liquid discharged from the nozzle at the time of flushing is received by the liquid receiving portion, and drips along the outer periphery of the liquid receiving portion. As a result, excess liquid does not stay on the surface of the liquid receiving portion on which the liquid discharged from the nozzles reaches during flushing, so that the liquid itself that is dried and deposited can be reduced. In addition, the liquid that is still deposited is scraped by the scraping unit that is in contact with the liquid receiving unit by controlling the rotation amount, the rotation speed, and the rotation timing by the control unit and rotating the liquid receiving unit by the rotating unit. I was able to take it. As a result, the liquid deposited on the surface of the liquid receiving portion on which the liquid ejected from the nozzles land during flushing can be removed, so that it is possible to prevent printing defects due to liquid accumulation.

  Application Example 2 In the liquid ejection apparatus according to the application example, it is preferable that the control unit intermittently operates the rotating unit.

According to this application example, since the rotation unit is intermittently operated by the control unit, wear of the liquid receiving unit and the scraping unit can be reduced as compared with the case where the rotation unit is always operated.
Therefore, the effect of reducing the wear of the liquid receiving portion and the scraping portion can be obtained.

  Application Example 3 In the liquid ejecting apparatus according to the application example described above, it is preferable that the liquid receiving portion is formed in a cylindrical shape and receives the liquid discharged downward from the nozzle on a curved surface.

According to this application example, since the liquid receiving portion has a cylindrical shape, the falling distance of the liquid discharged from the nozzle can be kept constant at any position after the rotation, and the liquid is misted. The liquid can be stably adhered to the liquid receiving portion while reducing (fogging).
Therefore, the effect of reducing the mist formation of the discharged liquid can be obtained.

  Application Example 4 A liquid discharge method according to this application example includes a head having a nozzle that discharges a liquid, a liquid receiving unit that receives the liquid discharged from the nozzle when the head performs flushing, and the liquid receiver. A rotating unit that rotates the rotating unit, a control unit that controls the rotating unit, a scraping unit that scrapes the liquid received by the liquid receiving unit by contacting the rotating liquid receiving unit, A liquid ejection method using a liquid ejection apparatus comprising: a drawing operation for performing drawing by ejecting the liquid from the nozzle toward the recording medium while relatively moving the head and the recording medium; and A flushing operation for flushing the head, and a scraping operation for scraping off the liquid received by the liquid receiver by bringing the scraper into contact with the rotating liquid receiver. And wherein the Mukoto.

According to this application example, the liquid ejected from the nozzle at the time of flushing is received by the liquid receiving portion and dropped along the outer periphery of the liquid receiving portion, so that the liquid ejected from the nozzle at the time of flushing is landed. Since excess liquid does not remain on the surface of the liquid receiving portion, it is possible to reduce the liquid itself that accumulates by drying.
For the liquid that still accumulates, the controller controls the amount of rotation, rotation speed, and rotation timing, and the liquid receiver is rotated by the rotating unit, thereby scraping the liquid contacted with the liquid receiving unit. By being scraped off by the portion, it is possible to remove the liquid deposited on the surface of the liquid receiving portion on which the liquid discharged from the nozzle lands during flushing.
Therefore, it is possible to provide a liquid ejection method that can prevent printing defects due to liquid deposition.

  Application Example 5 In the liquid ejection method described in the application example, it is preferable that the scraping operation is performed intermittently.

  According to this application example, since the liquid discharge method performs the scraping operation intermittently, it is possible to reduce wear of the liquid receiving portion and the scraping portion rather than always performing the scraping operation. And wear of the scraping portion can be suppressed.

  Application Example 6 In the liquid ejection method according to the application example described above, it is preferable that the scraping operation is performed before the liquid deposit received by the liquid receiving unit comes into contact with the head.

In the liquid discharge method using the liquid discharge apparatus described in the above application example, when the deposit deposited by the liquid deposited on the liquid receiving portion comes into contact with the head, the head is soiled to cause nozzle clogging and the like, thereby causing discharge failure. A specific problem occurs such as.
According to this application example, the flushing is performed with a minimum frequency that does not cause a specific problem, so that the wear of the liquid receiving portion and the scraping portion can be further reduced.

  Application Example 7 In the liquid ejection method according to the application example described above, it is preferable that the scraping operation is performed after the drawing operation.

According to this application example, by performing the scraping operation after the drawing operation, a long time elapses between the drawing operation and the next drawing operation, so that the liquid adhering to the liquid receiving unit It will not stick to.
In addition, when the scraping operation is performed after the drawing operation, since the liquid flushed and received in the liquid receiving portion is in a soft state, the load of the liquid scraping by the scraping portion is light and easy to scrape. It is possible to reduce wear on the part and the scraping part.

Schematic which shows the structure of a liquid discharge apparatus. The block diagram which shows the structure of a liquid discharge apparatus. The figure explaining the structural example of a flushing unit.

(Embodiment 1)
FIG. 1 is a schematic cross-sectional view of a liquid ejection apparatus 1 according to an embodiment. FIG. 2 is a block diagram of the liquid ejection apparatus 1.
First, a schematic configuration of the liquid ejection apparatus 1 according to the embodiment will be described.
In the following description, when referring to “up and down direction” and “left and right direction”, the direction indicated by the arrow in FIG. 1 is used as a reference. In addition, the “front-rear direction” refers to a direction orthogonal to the paper surface in FIG.
In the present embodiment, a description will be given using roll paper (continuous paper) as a recording medium on which the liquid ejecting apparatus 1 records an image.

  As shown in FIGS. 1 and 2, the liquid ejection apparatus 1 according to the present embodiment includes a transport unit 20 as an example of a transport unit, and a transport path along which the transport unit 20 transports the roll paper 2. A head unit 30 having a feeding unit 10, a platen 29 as an example of a medium support unit, and a winding unit 90, and further performing printing (drawing) in a printing region R on the conveyance path; A carriage unit 40 as an example of a head moving unit, a heater unit 70 as an example of a heat supply unit, a blower unit 80 for sending air to the roll paper 2 on the platen 29, and a flushing unit 35 for flushing the head In the flushing unit 35, a turning unit as a turning part for turning a cylindrical pipe 36 (see FIG. 3) as a liquid receiving part. 20, and a controller 60 as a control unit which controls these units, etc. controls the operation of the liquid discharging apparatus 1, a detector group 50, a.

The feeding unit 10 feeds the roll paper 2 to the transport unit 20. The feeding unit 10 includes a winding shaft 18 around which the roll paper 2 is wound and rotatably supported, a relay roller 19 for winding the roll paper 2 fed from the winding shaft 18 and guiding the roll paper 2 to the transport unit 20; have.
The transport unit 20 transports the roll paper 2 sent by the feeding unit 10 along a preset transport path. As shown in FIG. 1, the transport unit 20 includes a relay roller 21 that is positioned horizontally to the right of the relay roller 19, a relay roller 22 that is positioned obliquely downward to the right when viewed from the relay roller 21, and the relay roller 22. 1st conveyance roller 23 located in the upper right direction as viewed from the platen 29 (upstream side in the conveyance direction) and a right side as viewed from the first conveyance roller 23 (downstream in the conveyance direction as viewed from the platen 29). The second transport roller 24, the reverse roller 25 positioned vertically downward as viewed from the second transport roller 24, the relay roller 26 positioned rightward as viewed from the reverse roller 25, and upward as viewed from the relay roller 26. And a delivery roller 27 which is positioned.

The relay roller 21 is a roller that winds the roll paper 2 sent from the relay roller 19 from the left side and loosens it downward.
The relay roller 22 is a roller that winds the roll paper 2 sent from the relay roller 21 from the left side and conveys it obliquely upward to the right.
The first transport roller 23 includes a first drive roller 23a driven by a motor (not shown), and a first driven roller 23b arranged to face the first drive roller 23a with the roll paper 2 interposed therebetween. have. The first transport roller 23 is a roller that pulls up the roll paper 2 slacked downward and transports it to the printing region R facing the platen 29. The first transport roller 23 is configured to temporarily stop transport during a period in which image printing is performed on a portion of the roll paper 2 on the print region R. In addition, when the first driven roller 23b rotates as the first drive roller 23a rotates by the drive control of the controller 60, the transport amount of the roll paper 2 positioned on the platen 29 (the length of the portion of the roll paper) Is adjusted).

  As described above, the transport unit 20 has a mechanism that transports the portion of the roll paper 2 wound between the relay rollers 21 and 22 and the first transport roller 23 by slacking downward. The slackness of the roll paper 2 is monitored by the controller 60 based on a detection signal from a slack detection sensor (not shown). Specifically, when a portion of the roll paper 2 slackened between the relay rollers 21 and 22 and the first transport roller 23 is detected by the slack detection sensor, a tension of an appropriate magnitude is applied to the portion. Therefore, the transport unit 20 can transport the roll paper 2 in a relaxed state. On the other hand, when the part of the roll paper 2 that has been loosened is not detected by the slack detection sensor, an excessive amount of tension is applied to the part, so that the roll paper 2 is transported by the transport unit 20. It is temporarily stopped and the tension is adjusted to an appropriate magnitude.

  The second transport roller 24 includes a second drive roller 24a driven by a motor (not shown), and a second driven roller 24b disposed so as to face the second drive roller 24a with the roll paper 2 interposed therebetween. have. The second transport roller 24 is a roller that transports the portion of the roll paper 2 on which the image is recorded by the head unit 30 in the horizontal right direction along the support surface of the platen 29 and then transports it vertically downward. Thereby, the conveyance direction of the roll paper 2 is changed. The second driven roller 24b rotates as the second drive roller 24a is driven to rotate by the drive control of the controller 60, whereby a predetermined amount given to the portion of the roll paper 2 located on the platen 29 is obtained. Tension is adjusted.

The reversing roller 25 is a roller that wraps the roll paper 2 sent from the second conveying roller 24 from the upper left side and conveys it diagonally upward to the right.
The relay roller 26 is a roller that winds the roll paper 2 sent from the reversing roller 25 from the lower left side and conveys it upward.
The delivery roller 27 winds the roll paper 2 sent from the relay roller 26 from the lower left side and sends it to the take-up unit 90.
As described above, the roll paper 2 moves sequentially through the rollers, whereby a transport path for transporting the roll paper 2 is formed. The roll paper 2 is intermittently conveyed along the conveyance path by the conveyance unit 20 in units of areas corresponding to the printing areas R.

The head unit 30 is for ejecting ink onto a portion of the roll paper 2 that has been fed into the printing region R on the transport path (on the platen 29) by the transport unit 20. The head unit 30 has a head 31 and a valve unit 34.
The head 31 has a nozzle row composed of a plurality of nozzles # 1 to # 180 for each color such as yellow (Y), magenta (M), cyan (C), and black (K) on the lower surface thereof. . The head 31 performs flushing for each nozzle row during flushing.
The nozzles # 1 to # 180 of each nozzle row are arranged in a straight line along the direction intersecting the transport direction of the roll paper 2. Each nozzle row is arranged in parallel with a space between each other along the moving direction (scanning direction) of the head 31. Each nozzle # 1 to # 180 is provided with a piezo element (not shown) as a drive element for ejecting ink. When a voltage having a predetermined time width is applied between the electrodes provided at both ends of the piezoelectric element, the piezoelectric element expands according to the voltage application time and deforms the side wall of the ink flow path. As a result, the volume of the ink flow path contracts according to the expansion and contraction of the piezo element, and the ink corresponding to the contraction is ejected from the nozzles # 1 to # 180 of the respective colors as droplets.

  The valve unit 34 is for temporarily storing ink, and is connected to the head 31 via an ink supply tube (not shown). For this reason, the head 31 can perform image printing by discharging the ink supplied from the valve unit 34 toward the portion of the roll paper 2 that has been transported from the nozzle onto the platen 29 and stopped. .

The carriage unit 40 is for moving the head 31. The carriage unit 40 includes a guide rail 41 extending in the left-right direction (indicated by a two-dot chain line in FIG. 1), a carriage 42 supported so as to reciprocate in the left-right direction (movement direction) along the guide rail 41, The carriage motor shown in the figure.
The carriage 42 is configured to move integrally with the head 31 by driving a carriage motor (not shown). The position of the carriage 42 (head 31 or each nozzle row) on the guide rail 41 (the position in the left-right direction) is determined by the rising edge and the falling edge in the pulse signal output from the encoder provided by the controller 60 to the motor (not shown). It can be obtained by detecting and counting this edge.
Then, when cleaning the head 31 after image printing, the carriage 42 moves together with the head 31 along the guide rail 41 to the upstream side in the transport direction (upstream in the transport direction as viewed from the platen 29). It stops at the home position HP for cleaning (see FIG. 1).

  A cleaning unit (not shown) is provided at the home position HP. This cleaning unit has a cap, a suction pump, and the like. When the carriage 42 is positioned at the home position HP, a cap (not shown) is in close contact with the lower surface (nozzle surface) of the head 31. When the suction pump (not shown) is operated with the cap in close contact, the ink in the head 31 is sucked together with the thickened ink and paper powder. In this way, the clogged nozzle recovers from the non-ejection state, thereby completing the head cleaning.

  Further, when flushing the head 31 after printing an image, the carriage 42 moves together with the head 31 from the platen 29 side toward the home position HP side. At this time, the head 31 performs a flushing operation in the flushing unit 35 disposed between the platen 29 and the home position HP while moving together with the carriage 42. The flushing unit 35 will be described in detail later.

The platen 29 supports the part of the roll paper 2 located in the printing region R on the conveyance path and heats the part. As shown in FIG. 1, the platen 29 is provided in correspondence with the printing region R on the conveyance path, and in a region along the conveyance path between the first conveyance roller 23 and the second conveyance roller 24. Has been placed. The platen 29 can heat the portion of the roll paper 2 by receiving supply of heat generated by the heater unit 70.
The heater unit 70 is for heating the roll paper 2 and has a heater (not shown). This heater has a nichrome wire, and the nichrome wire is arranged inside the platen 29 so as to be at a fixed distance from the support surface of the platen 29. For this reason, when the heater is energized, the nichrome wire itself generates heat, and heat can be conducted to the portion of the roll paper 2 located on the support surface of the platen 29. Since this heater is configured by incorporating a nichrome wire in the entire area of the platen 29, heat can be uniformly conducted to the portion of the roll paper 2 on the platen 29. In this embodiment, the part of the roll paper 2 is uniformly heated so that the temperature of the part of the roll paper 2 on the platen is 45 ° C. Thereby, the ink landed on the part of the roll paper 2 can be dried.

  The blower unit 80 includes a fan 81 as an example of a blower and a motor (not shown) that rotates the fan 81. The fan 81 rotates to send wind to the roll paper 2 on the platen 29 and dry the ink landed on the roll paper 2. As shown in FIG. 1, a plurality of fans 81 are provided on an openable / closable cover (not shown) provided on the main body. Each fan 81 is positioned above the platen 29 when the cover is closed, and faces the support surface of the platen 29 (the roll paper 2 on the platen 29).

  The winding unit 90 is for winding the roll paper 2 (image-printed roll paper) sent by the transport unit 20. This take-up unit 90 is fed from the relay roller 91 that is rotatably supported by the relay roller 91 for winding the roll paper 2 sent from the feed roller 27 from the upper left side and conveying it to the lower right side. And a take-up drive shaft 92 for taking up the roll paper 2.

  The rotation unit 120 is a rotation unit that rotates the cylindrical pipe 36 that is a part of the flushing unit 35. By the control drive of the controller 60, the cylindrical pipe 36 is rotated at a specified rotation amount, rotation speed, and rotation timing.

The controller 60 is a control unit for controlling the liquid ejection apparatus 1. As shown in FIG. 2, the controller 60 includes an interface unit 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface unit 61 is for transmitting and receiving data between the host computer 110 which is an external device and the liquid ejecting apparatus 1. The CPU 62 is an arithmetic processing device for controlling the entire liquid ejection device 1. The memory 63 is for securing an area for storing a program of the CPU 62, a work area, and the like. The CPU 62 controls each unit by a unit control circuit 64 according to a program stored in the memory 63.
The detector group 50 is for monitoring the state in the liquid ejection apparatus 1. For example, the detector group 50 is attached to a transport roller and is used for control such as transport of a medium, and detects the presence or absence of a transported medium. And a linear encoder for detecting the position of the carriage 42 (or head 31) in the moving direction (left-right direction).

In the liquid ejection apparatus 1 according to the embodiment, flushing is performed in the flushing unit 35.
Flushing refers to the inside of a nozzle to prevent the nozzle from becoming clogged due to thickening of the ink in the nozzle or bubbles from being mixed into the nozzle and preventing an appropriate amount of ink from being discharged. This is maintenance to keep it normal. Specifically, this is an operation for forcibly ejecting ink by applying a drive signal unrelated to the image to be printed to the drive element (piezo element). While ink is ejected from the nozzles selected based on the image data during normal printing, ink that is not related to printing is ejected during flushing, so many nozzles (all nozzles or defective ejection) A large amount of ink is discharged from the nozzle) toward the flushing unit 35. For this reason, ink mist is most likely to occur during flushing.

Here, in the conventional liquid ejecting apparatus, when the flushing is performed, the ink ejected toward the flushing box by the head is absorbed by the absorbent material disposed in the flushing box. As a result, it was possible to prevent contamination of the nozzle surface (nozzle plate) and the medium due to the occurrence of ink mist during flushing.
However, when the ink absorbed in the absorbent material is an ink with low re-dissolvability or re-dispersibility, when the ink is dried, the voids of the absorbent material are filled with the dry ink, so that the absorbent material can absorb the ink. Disappear. For this reason, the absorbing material does not perform its function, and the ink ejected toward the flushing box is not absorbed but accumulates on the absorbing material.
When ink is thus deposited on the absorbent material, the deposited ink may come into contact with the nozzle surface (nozzle plate) to stain or block the nozzle. This may cause printing defects such as missing dots.
On the other hand, in the liquid ejection apparatus 1 according to the present embodiment, ink ejected from the nozzles during flushing is received by the liquid receiving portion and dripped down along the outer periphery of the liquid receiving portion. As a result, excess ink does not remain on the surface of the liquid receiving portion on which the ink ejected from the nozzles during flushing lands, so that the amount of ink that is dried and deposited can be reduced. Still further, the ink that accumulates is scraped by the scraping section that is in contact with the liquid receiving section by controlling the rotation amount, rotation speed, and rotation timing by the control section and rotating the liquid receiving section by the rotating section. I was able to take it. As a result, it is possible to remove ink deposited on the surface of the liquid receiving portion on which ink ejected from the nozzles is landed during flushing, thereby preventing printing defects due to ink accumulation.

A configuration example of the flushing unit 35 will be described with reference to FIGS. 1 and 3. FIG. 3 is a diagram illustrating a configuration example of the flushing unit 35.
As shown in FIG. 3, the flushing unit 35 includes a cylindrical pipe 36 as an example of a liquid receiving portion and a scraper 38 as an example of a scraping portion. As shown in FIG. 1, the flushing unit 35 is provided on the upstream side in the transport direction as viewed from the platen 29.
The cylindrical pipe 36 is formed in a cylindrical shape and receives the ink ejected from the nozzles during flushing with a curved surface. Moreover, the rotation part of the cylindrical pipe 36 rotates by control of the controller 60 as a control part. Although it is preferable to use a dedicated motor for the drive mechanism of the rotating portion, the present invention is not limited to this. As another example, a belt / pulley mechanism may be used. Specifically, pulleys are fitted to the rotating shaft (cylindrical shaft) of the cylindrical pipe 36 and the drive shaft of the motor, respectively, and a belt is bridged between the pulleys. And by the rotational drive of a motor, the driving force is transmitted to the cylindrical pipe 36 via a belt, and the cylindrical pipe 36 rotates.

The scraper 38 scrapes ink received by the cylindrical pipe 36 (ink adhering to the curved surface) by contacting the surface (curved surface) of the rotating cylindrical pipe 36. The scraper 38 according to the present embodiment is made of an elastic member such as rubber and is in contact with the surface below the cylindrical pipe 36 as shown in FIG.
As shown in FIG. 3, when the cylindrical pipe 36 with the ink attached to the surface rotates while the scraper 38 is in contact with the surface of the cylindrical pipe 36, the ink attached to the surface is moved by the scraper 38. It is scraped off and comes off from the surface. The cylindrical pipe 36 can return to the state before the ink attached to the surface is removed and the ink is attached to the surface. The ink peeled from the surface is stored in a box (not shown).
Since the scraper 38 is detachably attached, when the scraper 38 deteriorates, it can be replaced with another new scraper 38. Further, an urging mechanism (not shown) for urging the scraper 38 toward the cylindrical pipe 36 is provided. When the urging mechanism urges the scraper 38, the tip of the scraper 38 comes into close contact with the surface of the cylindrical pipe 36. Note that the urging mechanism may include a mechanism for moving the scraper 38 in a stepwise manner between the contact position and the standby position where the scraper 38 is not urged. In this case, the amount of adhesion of the scraper 38 to the cylindrical pipe 36 can be changed by controlling the biasing mechanism according to the hardness of the accumulated ink attached to the surface of the cylindrical pipe 36, so that the accumulated ink is removed with appropriate adhesion. In addition, wear of the scraper 38 can be reduced.
As described above, the liquid receiving portion in this embodiment is the cylindrical pipe 36 formed in a cylindrical shape, and is configured to be rotatable by the rotating portion. However, the falling distance of the ink ejected from the nozzle can be kept constant, and the mist formation of the ink can be reduced.

Next, the flushing operation when the flushing unit 35 is used will be described with reference to FIG. For convenience, the flushing operation will be described using the head 31 having two nozzle rows (A row and B row) on the lower surface.
Various operations of the liquid ejection apparatus 1 are mainly realized by the controller 60. In particular, this embodiment is realized by the CPU 62 processing the program stored in the memory 63. And this program is comprised from the code | cord | chord for performing the various operation | movement demonstrated below.

When a control signal for the flushing operation from the host computer 110 is input to the controller 60 via the interface unit 61, the carriage 42 positioned in the printing region R is moved along the guide rail 41 under the control of the unit control circuit 64. Then, the platen 29 moves to the home position HP side. Since the carriage 42 moves integrally with the head 31, the head 31 also moves from the platen 29 side to the home position HP side. The head 31 repeats the flushing operation for each nozzle row while moving in the flushing unit 35 disposed between the platen 29 and the home position HP under the control of the unit control circuit 64.
Specifically, first, as shown in FIG. 3, the moving head 31 is arranged such that the nozzle in the A row is located at the position where the linear distance from the nozzle forming the A row to the cylindrical axis of the cylindrical pipe 36 is the shortest. Flush the column. That is, the head 31 forcibly ejects ink downward from each nozzle forming the A row at the position. The ink ejected from each nozzle lands on the curved surface of the cylindrical pipe 36. Subsequently, the head 31 that continues to move also performs flushing on the nozzle rows of the B row, and the ink ejected from each nozzle lands on the curved surface of the cylindrical pipe 36, and the flushing operation is completed.
When this flushing operation is repeated, ink accumulates on the surface of the cylindrical pipe 36, but this ink drips along the outer periphery of the cylindrical pipe 36 by the curved surface of the cylindrical pipe 36 before contacting the nozzle surface. A thin liquid ink layer is formed on the trajectory through which the dropped ink passes, and eventually changes to a thin dry ink layer. When the flushing operation is further repeated, a thin dry ink layer is laminated, and ink deposited on the surface of the cylindrical pipe 36 is formed.

The rotation of the cylindrical pipe 36 under the control of the controller 60 as the control unit can always be operated. However, the wear of each of the cylinder pipes 36 and the scraper 38 is caused to advance by the amount of rotation of the cylindrical pipe 36 by contacting the cylinder pipe 36 and the scraper 38.
The problem to be solved by the present invention is that the accumulated ink comes into contact with the nozzle surface and causes printing failure. If this is interpreted from the opposite side, if the accumulated ink is removed before the accumulated ink contacts the nozzle surface, no printing failure will occur. Therefore, it is not always necessary to rotate the cylindrical pipe 36, and even when the accumulated ink is removed by the intermittent rotating operation, printing defects can be eliminated and the cylindrical pipe 36 and the scraper 38 are worn. Can be suppressed.
The controller 60 as a control unit controls this intermittent rotation operation.

Here, as the timing of the intermittent flushing operation, for example, in the rotation during the printing (drawing) operation, it is possible to perform printing according to the number of flushing to the cylindrical pipe 36 by grasping the ink deposition speed. By interrupting the operation and rotating the cylindrical pipe 36, it is possible to prevent printing failure.
Further, if the cylindrical pipe 36 is rotated at a high speed by the driving mechanism of the rotating unit and the rotating operation is completed at least by the time interval between the flushing operation and the flushing operation, the printing operation is interrupted and the production efficiency is lowered. Since there is nothing, it is more preferable.
Further, the part of the roll paper 2 on which the image is recorded is transported along the transport path in units corresponding to the printing region R, and is rotated by the time interval until the image is recorded on the part of the roll paper 2 again. If the operation is finished, it is more preferable because the printing operation is not interrupted and the production efficiency is not lowered.

  In addition, for example, if there is little ink accumulation on the cylindrical pipe 36 in one printing operation, and it takes a long time until the next printing operation, the ink deposited on the cylindrical pipe 36 is dried and solidified. Resulting in. Particularly when the scraper 38 is soft like rubber, it is difficult to remove the solidified ink. If this phenomenon is repeated, solidified ink that cannot be removed by the rotating operation accumulates, and causes contact with the nozzle surface to cause printing failure. Therefore, every time one printing operation is completed, that is, by rotating the cylindrical pipe 36 immediately after the printing operation (drawing operation), it may take a long time until the next printing operation. Since the ink is not attached to the surface of the cylindrical pipe 36, the ink is not solidified, and it is possible to prevent printing failure.

As described above, in the liquid ejection device 1 in the present embodiment, the following effects can be obtained.
The ink ejected from the nozzles during flushing is received by the cylindrical pipe 36 so as to sag along the outer periphery of the cylindrical pipe 36. As a result, excess ink does not remain on the surface of the cylindrical pipe 36 on which the ink ejected from the nozzles is landed during flushing, so that the ink itself that is dried and accumulated can be reduced. In addition, the accumulated ink is still scraper abutted on the cylindrical pipe 36 by controlling the rotation amount, rotation speed, and rotation timing by the controller 60 as the control unit and rotating the cylindrical pipe 36 by the rotation unit. 38 so that it can be scraped off. As a result, the ink deposited on the surface of the cylindrical pipe 36 on which the ink ejected from the nozzles land during flushing can be removed, so that it is possible to prevent printing defects due to ink accumulation.
Since the rotation unit is intermittently operated by the controller 60 as the control unit, wear of the cylindrical pipe 36 and the scraper 38 can be reduced as compared with the case where the rotation unit is always operated.

  In addition, by using the cylindrical pipe 36 as the liquid receiving portion, it is possible to keep the falling distance of the ink ejected from the nozzles at any position after the rotation, and to make the ink mist (mist-like). The ink can be stably attached to the cylindrical pipe.

  Although the embodiments of the present invention made by the inventor have been specifically described above, the present invention is not limited to the above-described embodiments and modifications thereof, and various modifications can be made without departing from the spirit of the present invention. It is possible to make changes.

  For example, in the above embodiment, an ink jet printer has been described as an example of the liquid ejection device, but the present invention is not limited to this. For example, a liquid ejection device that ejects liquid other than ink may be used. The present invention can be used for various liquid ejecting apparatuses including a liquid ejecting head that ejects a minute amount of liquid droplets. In addition, a droplet means the state of the liquid discharged from the said liquid discharge apparatus, and also includes what pulls a tail in granular shape, tear shape, and a thread form. The liquid here may be any material that can be discharged by the liquid discharge device. For example, it may be in a state in which the substance is in a liquid phase, such as a liquid with high or low viscosity, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts ) And a liquid as one state of a substance, as well as a material in which particles of a functional material made of a solid such as a pigment or metal particles are dissolved, dispersed or mixed in a solvent. Further, representative examples of the liquid include ink and liquid crystal as described in the above embodiment. Here, the ink includes general water-based inks and oil-based inks, and various liquid compositions such as gel inks and hot melt inks. As a specific example of the liquid ejection device, for example, a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, a color filter or the like in a dispersed or dissolved form. It may be a liquid ejecting apparatus for ejecting, a liquid ejecting apparatus for ejecting a bio-organic material used for biochip manufacturing, a liquid ejecting apparatus for ejecting liquid as a sample used as a precision pipette, a textile printing apparatus, a micro dispenser, or the like.

  In addition, a transparent resin liquid such as UV curable resin is used to form a liquid ejection device that ejects lubricating oil pinpoint to precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. A liquid discharge apparatus that discharges an acid or alkali or the like to etch the substrate or the like may be employed. The present invention can be applied to any one of these liquid ejection devices.

  DESCRIPTION OF SYMBOLS 1 ... Liquid discharge apparatus, 2 ... Roll paper as a recording medium, 10 ... Feed unit, 18 ... Winding shaft, 19 ... Relay roller, 20 ... Conveyance unit, 21 ... Relay roller, 22 ... Relay roller, 23 ... 1st Transport roller, 24 ... second transport roller, 25 ... reversing roller, 26 ... relay roller, 27 ... feed roller, 29 ... platen, 30 ... head unit, 31 ... head, 34 ... valve unit, 35 ... flushing unit, 36 ... Cylindrical pipe as a liquid receiving part, 38 ... Scraper as a scraping part, 40 ... Carriage unit, 41 ... Guide rail, 42 ... Carriage, 50 ... Detector group, 60 ... Controller as control part, 70 ... Heater unit, 80 ... Air blow unit, 81 ... Fan, 90 ... Winding unit, 91 ... Relay roller, 2 ... winding drive shaft, 110 ... host computer, 120 ... rotating unit.

Claims (7)

A head having a nozzle for discharging liquid;
A liquid receiving portion for receiving the liquid discharged from the nozzle by the head performing flushing;
A rotating part for rotating the liquid receiving part;
A control unit for controlling the rotating unit;
A scraping part for scraping off the liquid received by the liquid receiving part by contacting the rotating liquid receiving part;
A liquid ejection apparatus comprising: The liquid ejection device according to claim 1,
The liquid ejecting apparatus according to claim 1, wherein the control unit intermittently operates the rotating unit. The liquid ejection device according to claim 1 or 2,
The liquid receiver is formed in a cylindrical shape and receives a liquid discharged downward from the nozzle by a curved surface. A head having a nozzle for discharging liquid;
A liquid receiving portion for receiving the liquid discharged from the nozzle by the head performing flushing;
A rotating part for rotating the liquid receiving part;
A control unit for controlling the rotating unit;
A scraping part for scraping off the liquid received by the liquid receiving part by contacting the rotating liquid receiving part;
A liquid discharge method using a liquid discharge apparatus comprising:
A drawing operation for drawing by discharging the liquid from the nozzle toward the recording medium while relatively moving the head and the recording medium;
A flushing operation for flushing the head;
A liquid discharge method comprising: a scraping operation for scraping the liquid received by the liquid receiving portion by bringing the scraping portion into contact with the rotating liquid receiving portion. The liquid discharge method according to claim 4,
The liquid ejection method, wherein the scraping operation is performed intermittently. A liquid ejection method according to claim 4 or 5,
The liquid discharging method according to claim 1, wherein the scraping operation is performed before the liquid deposit received by the liquid receiving portion comes into contact with the head. A liquid ejection method according to any one of claims 4 to 6,
The liquid ejection method, wherein the scraping operation is performed after the drawing operation.

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