JP2014100799A - Liquid injection head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid injection head capable of reducing friction speed to follow wiping of a nozzle surface of a liquid injection head.SOLUTION: A wiping device wiping off a nozzle surface 39 of a liquid injection head 22 uses rubber wipers 59 of a first cleaning unit individually to wipe off a nozzle surrounding region 37 in the form of a concave portion exposed to an opening 36a of a head cover 36 on a nozzle surface 39 ((b) and (c) in figure). Next, a cloth wiper 61 of a second cleaning unit is used to wipe off entirely the nozzle surface 39 ((c) and (d) in figure). At this time, a pressing roller 67 constituting the cloth wiper 61 presses a portion of a cloth sheet 50 corresponding to a protruding surface 40. This can prevent the cloth wiper 61 from being strongly struck on the nozzle surrounding region 37.

Description

  The present invention relates to a liquid ejecting apparatus including a cleaning unit (wiping device) that wipes a liquid ejecting head.

  2. Description of the Related Art Conventionally, as a kind of liquid ejecting apparatus, an ink jet printer that prints (records) an image by ejecting ink as an example of liquid from a liquid ejecting head onto a medium such as paper is known (for example, Patent Document 1). etc). Such a printer is usually provided with a maintenance device in order to maintain the ejection characteristics of the liquid from the liquid ejection head.

  For example, the printer described in Patent Document 1 is provided with a cleaner cartridge that wipes the nozzle surface after applying a wet liquid such as a cleaning liquid to the nozzle surface of the liquid ejecting head as a head maintenance device of this type. This cleaner cartridge has a non-absorbent rubber blade (rubber wiper) that wipes off the wet liquid by wiping off the nozzle cover (head cover) that is convex with respect to the nozzle forming surface, and the nozzle mounting surface (nozzle peripheral area) And a wiping web having an absorptivity for recovering the wet liquid from the nozzle arrangement surface by absorption. Since there is a step corresponding to the thickness of the nozzle cover between the nozzle cover part and the nozzle arrangement surface, the nozzle surface is an uneven surface where the nozzle arrangement surface part is a concave part and the nozzle cover part is a convex part. It has become.

Japanese Patent Laying-Open No. 2011-79170 (for example, paragraph [0131], FIG. 15, FIG. 16, etc.)

  By the way, in the printer described in Patent Document 1, a portion of the nozzle cover that becomes a convex portion on the nozzle surface is wiped with a blade, and a nozzle arrangement surface that becomes a concave portion is wiped with a wiping web. When the nozzle arrangement surface (nozzle peripheral area) is wiped with the wiping web, the fibers of the wiping web rub against the nozzle arrangement surface, which causes a problem that the nozzle arrangement surface is easily worn. In particular, in the case of pigment ink, the nozzle arrangement surface is more easily worn by the abrasive effect of pigment particles in the pigment ink absorbed by the wiping web. Normally, a liquid repellent film is formed on the nozzle arrangement surface, and when this liquid repellent film wears and decreases, the liquid repellency of the nozzle arrangement surface decreases and ink mist adhering to the nozzle arrangement surface, etc. The ink becomes wet and spreads easily. When the ink droplets ejected from the nozzle come into contact with the ink that has spread wet to the vicinity of the nozzle, this contact induces the flying bend of the ink droplet, and the landing position (dot position) of the ink droplet on the medium is shifted. As a result, the print quality is degraded. Even if the liquid is dye ink or wet liquid, if the nozzle arrangement surface is rubbed against the fibers of the wiping web, the nozzle arrangement surface is easily worn. In addition, even when the nozzle surface is flat and has no irregularities, it is desirable that the periphery of the nozzle be suppressed from being worn by wiping.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a liquid ejecting apparatus that can reduce the wear rate associated with wiping the nozzle surface of the liquid ejecting head.

  A liquid ejecting apparatus that solves the above-described problem is capable of wiping off a liquid ejecting head that ejects liquid from a plurality of nozzles arranged on a nozzle surface, and liquid adhering to a nozzle peripheral region that is a region including the nozzle on the nozzle surface A first cleaning unit, and a second cleaning unit capable of absorbing liquid adhering to the outer region by contacting an outer region other than the nozzle peripheral region on the nozzle surface.

  According to this configuration, the liquid adhering to the nozzle peripheral region on the nozzle surface is wiped away by the first cleaning unit. Moreover, the liquid adhering to at least the outer region other than the nozzle peripheral region is absorbed by the second cleaning unit. For example, when particles dispersed in the liquid (for example, particles such as pigment) are included, the absorbed particles in the liquid are interposed between the wiping surface and the nozzle peripheral region is formed by the abrasive effect. There is a worry to wear. However, the second cleaning unit comes into contact with the outer region and does not contact the nozzle peripheral region or even makes contact with the nozzle peripheral region. Accordingly, it is possible to reduce the wear of the nozzle peripheral region caused by the second cleaning unit contacting the nozzle peripheral region with the same strength as the outer region.

  In the liquid ejecting apparatus, it is preferable that after the liquid adhering to the nozzle peripheral region is wiped off by the first cleaning unit, the second cleaning unit is brought into contact with the outer region of the nozzle surface.

  According to this configuration, after the liquid adhering to the nozzle peripheral region is wiped by the first cleaning unit, the second cleaning unit is brought into contact with a region other than the nozzle peripheral region on the nozzle surface. For this reason, the liquid remaining in the nozzle peripheral region can be absorbed by the second cleaning unit.

  In the liquid ejecting apparatus, it is preferable that the outer region includes a protruding surface that protrudes from the nozzle peripheral region around the nozzle peripheral region, and the second cleaning unit moves in contact with the protruding surface. .

  According to this configuration, the second cleaning unit absorbs the liquid attached to the outer region by moving in contact with the protruding surface protruding from the nozzle peripheral region around the nozzle peripheral region of the nozzle surface. Even if the nozzle surface has irregularities that are concave in the peripheral area of the nozzle and convex in the protruding surface, the liquid adhering to the nozzle surface can be wiped off to a small extent.

Furthermore, in the liquid ejecting apparatus, it is preferable that the protruding surface has lower liquid repellency than the nozzle peripheral region.
According to this configuration, since the liquid on the projecting surface is easily spread out, the second cleaning unit can easily absorb the liquid on the projecting surface. For example, when the liquid repellency is high and the liquid does not wet and spread, the liquid is absorbed at the same location of the second cleaning unit, so the absorption performance of the second cleaning unit gradually decreases and absorbs the liquid. It becomes difficult. However, since the protruding surface has lower liquid repellency than the peripheral area of the nozzle, the second cleaning unit can efficiently absorb the liquid on the protruding surface.

In the liquid ejecting apparatus, it is preferable that the first cleaning unit includes a rubber wiper and the second cleaning unit includes a belt-shaped cloth that abuts against the outer region.
According to this configuration, the first cleaning unit wipes the nozzle peripheral area with the rubber wiper. The cloth adhering to the outer region can be absorbed by bringing the belt-like cloth of the second cleaning unit into contact with the outer region (projecting surface as an example) other than the nozzle peripheral region.

  In the liquid ejecting apparatus, the second cleaning unit includes a pressing unit that can press the belt-shaped cloth against the nozzle surface side, and the pressing unit has a pressing force against the nozzle peripheral region of the cloth. It is preferable that the pressure is set to be weaker than the pressing force with respect to the outer region.

  According to this configuration, since the second cleaning unit presses the cloth against the outer region other than the region around the nozzle by the pressing force of the pressing unit, the liquid attached to the outer region can be effectively absorbed. Further, since the cloth abuts against the nozzle peripheral region with a pressing force weaker than that of the outer region, the nozzle peripheral region is not easily worn.

In the liquid ejecting apparatus, it is preferable that the wiping direction of the first cleaning unit and the wiping direction of the second cleaning unit are the same.
According to this configuration, since the wiping direction of the first cleaning unit and the wiping direction of the second cleaning unit are the same, after wiping the nozzle peripheral region, the remaining wiping liquid remaining along the wiping direction is It can be effectively absorbed by the second cleaning device.

Furthermore, in the liquid ejecting apparatus, it is preferable that the first cleaning unit includes a rubber wiper having a shape that is convex toward the wiping direction.
According to this configuration, when wiping with a rubber wiper having a convex shape toward the wiping direction, a part of the liquid flowing from the front side of the wiping direction (traveling direction) of the rubber wiper to both sides of the rubber wiper is Remains on both sides. The liquid remaining on both sides tends to be distributed relatively evenly in the wiping direction. For this reason, after that, when the second cleaning unit moves while abutting the outer region (as an example, a protruding surface) and absorbs the liquid adhering to the outer region, the liquid remaining on both sides of the wiping path of the first cleaning unit Is efficiently absorbed even in a wiping manner in which the second cleaning portion moves while contacting the outer region.

1 is a perspective view of a printer according to an embodiment. FIG. 3 is a perspective view of a liquid ejecting head. FIG. 3 is a schematic bottom view of a liquid ejecting head. FIG. 3 is a schematic cross-sectional view of a liquid ejecting head. The schematic side view of a wiping apparatus. The partial perspective view of a wiping apparatus. The schematic bottom view explaining the wiping operation | movement of a rubber wiper. The fragmentary front sectional view which shows the structure of a wiping apparatus. (A) is a schematic side view explaining the wiping operation | movement of a rubber wiper, (b) is a schematic side view explaining the wiping operation | movement of a cloth wiper. (A)-(d) is a partial model bottom view explaining the wiping process of a nozzle surface. (A) is a schematic front view which shows the ink adhesion state after completion | finish of wiping of a rubber wiper, (b) is a typical front sectional view explaining the wiping operation | movement of a cloth wiper. The schematic plan view which shows the wiping system of a modification. The typical front sectional view which shows a part of wiping apparatus of a modification. The schematic side sectional view which shows a part of wiping apparatus of a modification.

Hereinafter, an ink jet printer that is an example of a liquid ejecting apparatus will be described with reference to FIGS.
As shown in FIG. 1, a substantially square plate-like support member 13 extends along the main scanning direction X (left and right direction in FIG. 1) at a lower portion inside a frame 12 having a substantially rectangular box shape whose upper side opens in the printer 11. It is arranged in an extended state. The recording medium P is orthogonal to the main scanning direction X on the support member 13 by a feed roller and a transport roller pair (both not shown) driven by the power of the transport motor 14 provided at the lower rear side of the frame 12. Is transported in the sub-scanning direction Y (conveyance direction). A carriage 17 is supported on a guide shaft 16 installed above the support member 13 in a state where the carriage 17 can reciprocate in the main scanning direction X.

  A drive pulley 18 and a driven pulley 19 are rotatably supported on the frame 12 at positions near both ends of the guide shaft 16. An output shaft of a carriage motor 20 serving as a power source when the carriage 17 is reciprocated is connected to the drive pulley 18. An endless timing belt 21, which is partially connected to the carriage 17, is hung between the pair of pulleys 18 and 19. Therefore, the carriage 17 can reciprocate in the main scanning direction X while being guided by the guide shaft 16 by the timing belt 21 being rotated forward and backward by the power of the carriage motor 20.

  A liquid ejecting head 22 is provided at the lower portion of the carriage 17, and a plurality (five in this embodiment) of ink cartridges 23 for storing ink (liquid) supplied to the liquid ejecting head 22 are detachable on the upper side thereof. It is installed. Then, an ink droplet is ejected from the liquid ejecting head 22 onto the recording medium P fed onto the support member 13, whereby an image or the like is recorded on the recording medium P. Note that the recording medium P to be printed (recorded) by the printer 11 of the present embodiment is, for example, paper, cloth, film, or the like. The printer 11 can also print, for example, towels, clothing (such as shirts), and the like.

  As an example, the five ink cartridges 23 store cyan (C), magenta (M), yellow (Y), black (K), and white (W) inks, respectively. By ejecting the ink supplied from each ink cartridge 23 from the liquid ejecting head 22, it is possible to perform white printing (background printing), color printing, and the like on the dark recording medium P. The mounting method of the ink cartridge 23 is not limited to the so-called on-carriage type in which the ink cartridge 23 is mounted on the carriage 17, but the so-called off-carriage type in which the ink cartridge 23 is detachably mounted on the cartridge holder on the printer body side. Good.

  Further, as shown in FIG. 1, a maintenance device 26 for performing maintenance of the liquid ejecting head 22 is provided below the home position HP in which the carriage 17 stands by when not printing in the frame 12. The maintenance device 26 includes a wiping device 27 for wiping the liquid ejecting head 22, a capping device 28 having a cap 28 a for capping the liquid ejecting head 22, and a viscosity increase from the nozzle of the liquid ejecting head 22 by sucking the inside of the cap 28 a. And a suction pump (not shown) that is driven when sucking and discharging ink or the like. In the flushing in which the liquid ejecting head 22 ejects ink droplets unrelated to printing for the purpose of nozzle cleaning, the cap 28a is used as the ink droplet ejection destination.

  As shown in FIG. 1, a linear encoder 29 that outputs a number of pulses proportional to the amount of movement of the carriage 17 is provided at a position on the back side of the carriage 17 in the frame 12 so as to extend along the guide shaft 16. Yes. Further, the printer 11 is provided with a controller C that controls printing control and maintenance control. The controller C drives and controls the carriage motor 20 based on the output pulse signal of the linear encoder 29, and performs position control and speed control of the carriage 17. The controller C controls the drive of the transport motor 14 and feeds and transports the recording medium P. Further, when the controller C determines that the maintenance execution condition is satisfied, the controller C moves the carriage 17 to a predetermined position on the home position HP side, and then drives at least one of the wiping device 27 and the capping device 28 to perform wiping and cleaning. Perform necessary maintenance.

  The head unit 30 shown in FIG. 2 is attached to the lower surface portion of the carriage 17, and includes a bracket portion 31 for attachment to the carriage 17 and a square columnar liquid jet head 22 protruding downward from the bracket portion 31. The liquid ejecting head 22 includes a quadrangular columnar flow passage forming portion 32 that protrudes downward from the bracket portion 31, and a square plate-like head main body 33 that is fixed to the lower side of the flow passage forming portion 32. A plurality of rows (10 rows in the example of FIG. 2) of nozzle rows 34 are formed on the lower surface of the head body 33 in FIG. Further, on the lower surface side of the head main body 33, a head cover 36 having a plurality of (five in the example of FIG. 2) openings 36a is formed with nozzles 38 (see FIG. 3) constituting the nozzle row 34 formed therein. It is attached so as to partially cover the surface 35 (the lower surface in this example). The plurality of nozzle rows 34 are exposed by a predetermined number of rows (two rows in the example of FIG. 2) from one opening 36a. In this example, a region exposed by the opening 36 a in the nozzle forming surface 35 is a nozzle peripheral region 37.

  The head cover 36 shown in FIG. 3 and FIG. 4 is fixed to the liquid ejecting head 22 by a fixing structure such as locking in a state of covering a portion other than the nozzle peripheral area 37 exposed by the opening 36 a in the nozzle forming surface 35. Yes. The entire bottom surface of the liquid jet head 22 shown in FIG. 3 is a nozzle surface 39 that becomes a surface to be wiped by the wiping device 27. The nozzle surface 39 is a nozzle peripheral region 37 (that is, a region in the opening 36 a) and an outer region other than the nozzle peripheral region 37, and protrudes from the nozzle peripheral region 37 by an amount corresponding to the thickness of the head cover 36. And a projecting surface 40. A step 41 corresponding to the thickness of the head cover 36 exists between the nozzle peripheral region 37 and the protruding surface 40, and the nozzle surface 39 is a concave portion at the nozzle peripheral region 37 portion and a convex portion at the protruding surface 40 portion. It has become an uneven surface. The head cover 36 is made of metal (for example, stainless steel).

  As shown in FIG. 3, the nozzle row 34 includes a large number (for example, 180 or 360) of nozzles 38 arranged at a constant pitch along the sub-scanning direction Y. Each nozzle row 34 corresponds to the ink color of the ink cartridge 23, and for example, ink of any one of cyan (C), magenta (M), yellow (Y), black (K), and white (W) is used. Spray. Of course, colors other than the four colors of CMYK and white (W) can also be adopted. Examples of other ink colors include light magenta, light cyan, light yellow, gray, and orange. Further, the number of colors of the liquid ejecting head 22 may be CMYK 4 colors, CMY 3 colors, black 1 color, or the like. Further, an unused nozzle row in which ink is not ejected may exist in the plurality of nozzle rows 34.

  Further, the nozzle forming surface 35 shown in FIG. 3 is subjected to a liquid repellent treatment (ink repellent treatment) that easily repels ink, and a liquid repellent film 42 (ink repellent film) is formed on the surface. . The ink used in this embodiment is a pigment ink as an example. In pigment ink, a large number of pigment particles are dispersed in a liquid used as a dispersion medium. Organic pigments with an average particle size of about 100 nm as cyan, magenta and yellow pigments, carbon black (inorganic pigment) with an average particle size of about 120 nm as black pigments, and titanium oxide (with an average particle size of about 320 nm as white pigments) Inorganic pigments) can be used. The ink of this example is a water-based ink, and many pigment particles are dispersed in water which is a dispersion medium. Therefore, in this example, the liquid repellent film 42 is a water repellent film having a function of repelling water-based ink. The liquid-repellent film 42 is gradually worn by repeated wiping on the nozzle forming surface 35, and when the liquid-repellent film 42 is worn more than a certain level, its liquid-repellent characteristics are deteriorated.

  In the lowered state of the liquid repellency, the wetting angle of the liquid such as ink mist with respect to the nozzle peripheral region 37 becomes small. For this reason, the plurality of ink mists adhering to the nozzle peripheral region 37 spreads wet and easily grows into one relatively wide ink droplet (attached ink). As a result, this kind of attached ink may be present around the nozzle 38, partially block the opening of the nozzle 38, and further flow into the nozzle 38. If an ink droplet is ejected from the nozzle 38 in this state, the ejected ink droplet comes into contact with the adhering ink and induces a flying bend of the ink droplet. This type of ink droplet flying bend causes the landing position of the ink droplet on the recording medium P (that is, the print dot formation position) to deviate from the assumed position, resulting in a decrease in print image quality. For this reason, it is necessary to suppress the wear of the liquid repellent film 42 due to wiping as much as possible.

  On the other hand, the head cover 36 is manufactured by processing a metal plate into a predetermined shape, and the surface is not subjected to liquid repellent treatment. For this reason, the protruding surface 40 has lower liquid repellency than the nozzle peripheral region 37. That is, the ink wetting angle with respect to the protruding surface 40 is smaller than the ink wetting angle with respect to the nozzle peripheral region 37.

  As shown in FIG. 4, the liquid ejecting head 22 has a plurality (five in the present embodiment) of recording heads 43 (unit heads) arranged in parallel at regular intervals in the main scanning direction X. ing. A peripheral portion of the nozzle forming surface 35 which is the lower surface of the recording head 43 is covered with a head cover 36, and a nozzle peripheral region 37 including nozzles 38 for two rows is exposed from the opening 36a. Each nozzle 38 communicates with each ink flow path 32a that passes through the flow path forming portion 32, and each ink flow path 32a protrudes upward from the upper surface of the flow path forming portion 32 through a flow path (not shown). It communicates with the supply pipe section 30a. Each supply pipe portion 30a communicates with a supply port of each ink cartridge 23 mounted on the carriage 17 or a cartridge holder (not shown) on the printer main body via a flow path (not shown). Accordingly, each color ink corresponding to the nozzle 38 of the corresponding recording head 43 is supplied from each ink cartridge 23 (see FIG. 1) through each supply pipe portion 30a and the ink flow path 32a.

  As shown in FIGS. 3 and 4, the nozzle surface 39 of the liquid jet head 22 is recessed at the projecting surface 40 that is a portion around the opening 36 a on the lower surface of the head cover 36 and the portion of the opening 36 a as described above. And an exposed nozzle peripheral region 37. In FIG. 4, in order to make the uneven shape of the nozzle surface 39 easy to understand, the thickness of the head cover 36 is exaggerated to be larger than the actual thickness.

  Next, the wiping device 27 will be described with reference to FIG. As shown in FIG. 5, the wiping device 27 includes a wiper unit 46 that can reciprocate in the wiping direction, and a rail portion 47 that guides the wiper unit 46 so as to be movable in the wiping direction. The wiper unit 46 includes a wiper cassette 51 on which a cloth sheet 50 as an example of a belt-like cloth that contacts the nozzle surface 39 and absorbs ink is mounted, and a wiper holder 52 to which the wiper cassette 51 is detachably mounted. . The wiper holder 52 is guided along the rail portion 47 via a guide portion 52a fixed to the lower portion thereof, and can reciprocate in the wiping direction (sub-scanning direction Y). On the printer main body side (for example, the frame 12), an electric motor 54 that is a power source and a power transmission mechanism 55 that transmits the power of the electric motor 54 are provided.

  As shown in FIG. 5, a rack and pinion mechanism 56 is provided on the side of the wiper holder 52. The rack and pinion mechanism 56 is fixed to the side surface of the wiper holder 52 in a direction in which the longitudinal direction thereof coincides with the wiping direction, and meshes with the rack gear portion 56a and is transmitted via the power transmission mechanism 55. And a pinion gear portion 56b that rotates with the generated power. When the electric motor 54 is driven to rotate forward, the pinion gear portion 56b rotates forward, and the wiper holder 52, together with the rack gear portion 56a, moves forward from the retracted position shown in FIG. 5 to the downstream side in the transport direction Y (leftward in FIG. 5). When the electric motor 54 stopped after the forward movement is driven in reverse, the pinion gear portion 56b meshing with the rack gear portion 56a is reversely rotated, and the wiper holder 52 is moved backward in the transport direction Y (rightward in FIG. 5). 5 returns to the retracted position shown in FIG.

  As shown in FIG. 5, the wiper unit 46 protrudes upward from the first cleaning portion 60 having a plurality of (for example, five) rubber wipers 59 protruding upward from the upper surface portion of the wiper cassette 51. And a second cleaning unit 62 having a semi-cylindrical cloth wiper 61. The plurality of rubber wipers 59 are disposed at a position that is a predetermined distance ahead of the cloth wiper 61 in the traveling direction of the wiper unit 46 when the wiper unit 46 moves forward. Then, the wiper unit 46 moves in the wiping direction along the rail portion 47 from the retracted position shown in FIG. 5, whereby the rubber wiper 59 and the second cleaning portion of the first cleaning portion 60 with respect to the nozzle surface 39 of the liquid ejecting head 22. Wiping with the 62 cloth wipers 61 is sequentially performed.

  As shown in FIG. 5, in the wiper cassette 51, a feeding shaft 63 and a winding shaft 64 are pivotally supported with a predetermined distance in the wiping direction. A feeding roll 65 around which an unused cloth sheet 50 is wound is mounted on the feeding shaft 63. The take-up shaft 64 is provided with a take-up roll 66 on which the used cloth sheet 50 is taken up. The cloth sheet 50 hung between the two rolls 65 and 66 is an outer peripheral surface of a pressing roller 67 as an example of a pressing portion that partially protrudes upward from an opening 51a (see FIG. 6) at the center of the upper surface of the wiper cassette 51. A semi-cylindrical cloth wiper 61 is formed at the portion wound around the pressure roller 67 from above. The support shaft 67a that supports the pressing roller 67 is biased upward by a spring 68, and the cloth wiper 61 is biased upward. The second cleaning part 62 includes these parts 63 to 68, and has a function of applying a biasing force to the cloth wiper 61 toward the side in contact with the nozzle surface 39 and a part wound around the pressing roller 67 of the cloth sheet 50. It has a sheet exchange function for exchanging used ones to unused ones.

  Here, in the state where the wiper unit 46 shown in FIG. 5 is in the forward movement end position, for example, power transmission to the pinion gear portion 56b is interrupted by a clutch mechanism (not shown) in the power transmission mechanism 55, and the feeding shaft 63 The winding shaft 64 is connected to the power transmission mechanism 55 so as to be able to transmit power. In this state, the feeding shaft 63 and the winding shaft 64 are rotated by the power transmitted from the electric motor 54 via the power transmission mechanism 55, and the unused cloth sheet 50 is fed out from the feeding roll 65, and the winding is performed. The used cloth sheet 50 is wound around the take-up roll 66. During this time, the carriage 17 is retracted from the wiping position. Then, after the wiping operation so far is finished, when the electric motor 54 is driven in reverse, the wiper unit 46 moves backward and returns to the retracted position shown in FIG. The clutch mechanism may be a mechanism capable of releasing the meshing of the pinion gear portion 56b with the rack gear portion 56a and switching to a state where power can be transmitted to the take-up shaft 64. In addition, a known clutch mechanism can be employed.

  As shown in FIG. 6, the plurality of rubber wipers 59 provided in the first cleaning unit 60 holds a strip-like rubber blade 70 and a posture in which the blade 70 can be wiped on the upper surface portion of the wiper cassette 51. A holding member 71. Each blade 70 is held at each position where the pitch in the width direction orthogonal to the wiping direction is the same as the pitch of each nozzle peripheral region 37 on the liquid ejecting head 22 side, and wipes the corresponding nozzle peripheral region 37 respectively. It is possible. The blade 70 according to the present embodiment has a cross-sectional shape that is broken on a surface parallel to the nozzle surface 39 (that is, a surface parallel to the upper surface portion of the wiper cassette 51), and has a curved shape in which the traveling direction (forward movement direction) side during wiping is convex It is held by a holding member 71 so as to have a shape. The blade 70 is held in a curved shape as described above in order to produce a stiffness necessary for wiping although the thickness of the blade 70 is thin, and when the rubber wiper 59 is wiped, the blade 70 flows to both sides of the wiping path. This is because the distribution of the remaining ink in the wiping direction is almost uniform.

  Further, the axial length of the semi-cylindrical cloth wiper 61 shown in FIG. 6 is slightly longer than the length (width) in the main scanning direction X of the nozzle surface 39 on the liquid ejecting head 22 side. For this reason, the entire nozzle surface 39 can be wiped by the cloth wiper 61. A plurality (six in this example) of pressing rollers 67 are arranged in the axial direction with an interval corresponding to the width of the opening 36a (see FIGS. 2 and 3) on the liquid jet head 22 side with respect to the support shaft 67a. With this configuration, the portion of the cloth sheet 50 that is wound around the pressing roller 67 can be selectively pressed against the protruding surface 40 of the nozzle surface 39. The cloth sheet 50 is not strongly pressed against the nozzle peripheral region 37 that is located in the opening 36 a corresponding to the gap between the pressing rollers 67.

  As shown in FIG. 7, the width of each rubber wiper 59 in the direction orthogonal to the wiping direction (the width in the left-right direction in FIG. 7) is set slightly shorter than the width of the nozzle peripheral region 37. Therefore, each rubber wiper 59 falls into the opening 36a of the head cover 36 and wipes the nozzle peripheral region 37 when the wiper unit 46 moves forward from the solid line position in FIG. Is possible.

  That is, when the electric motor 54 shown in FIG. 5 is driven to rotate forward, the wiper unit 46 moves forward in the wiping direction from the retracted position in FIG. In this forward movement process (wiping process), as shown in FIG. 9A, among the nozzle surfaces 39 of the liquid jet head 22 at the wiping position, first, a plurality of rubber wipers 59 respectively correspond to the respective nozzle peripheral regions 37. Next, as shown in FIG. 9 (b), the cloth wiper 61 moves while abutting mainly on the protruding surface 40 to selectively wipe the protruding surface 40. Then, after the wiping operation by the wipers 59 and 61 is completed, for example, the liquid ejecting head 22 is retreated from the wiping position in the main scanning direction X, and after this retraction, the electric motor 54 is driven in reverse and the wiper unit 46 is moved backward. Thus, each rubber wiper 59 returns from the two-dot chain line position in FIG. 7 to the solid line position.

Next, the operation of the printer 11 including the wiping device 27 will be described with reference to FIGS.
In the serial printer 11, a printing operation in which ink droplets are ejected from the nozzles 38 of the liquid ejecting head 22 while the carriage 17 is moving in the main scanning direction X, and recording is performed on the recording medium P. Printing on the recording medium P is advanced by alternately repeating the conveying operation of conveying to the printing position. During this printing, the wiper unit 46 of the wiping device 27 stands by at the retracted position shown in FIG.

  For example, every time printing of the recording medium P is completed, the controller C determines whether or not wiping is necessary. If it is determined that wiping is necessary, the controller 17 drives the carriage motor 20 to control the carriage 17 to the wiping position. Move. When the controller C determines that the carriage 17 has reached the wiping position and stopped based on the count value of a counter (not shown) that counts the output pulses of the linear encoder 29, the controller C drives the electric motor 54 to rotate forward. Then, the wiper unit 46 is guided from the retracted position to the rail portion 47 and moves forward in the wiping direction.

  As shown in FIG. 10A, the nozzle surface 39 of the liquid jet head 22 before wiping is in a state where ink mist M generated during printing is attached. Then, as the wiper unit 46 moves forward, as shown in FIG. 10B, the rubber wiper 59 first wipes the corresponding nozzle peripheral region 37. As a result, the ink mist M on the nozzle peripheral region 37 is scraped by the rubber wiper 59 along the wiping direction (the arrow direction in FIG. 5B). In particular, since the rubber wiper 59 has a curved shape that is convex in the wiping direction, a part of the ink swept by the rubber wiper 59 flows to both sides during the movement, and the remaining ink shown in black in FIG. R remains in a line shape at both ends (side edges) in the width direction of the nozzle peripheral region 37. The remaining ink R having such a line shape is substantially evenly distributed in the wiping direction (nozzle row direction).

  Next, as shown in FIG. 10C, the cloth wiper 61 moves in the wiping direction in contact with the nozzle surface 39 and wipes the entire nozzle surface 39. At this time, since the cloth sheet 50 is selectively pressed against the protruding surface 40 by the plurality of pressing rollers 67, the ink mist M on the protruding surface 40 is reliably absorbed by the cloth wiper 61.

  At this time, before wiping with the cloth wiper 61, as shown in FIGS. 10B and 10C, the line-like remaining ink R remaining on the peripheral edge of the nozzle peripheral region 37 is shown in FIG. Thus, it exists along the inner wall surface of the opening 36a. As a result, as shown in FIG. 11B, when the cloth wiper 61 is pressed against the nozzle surface 39, the remaining ink R is absorbed by the cloth wiper 61 along the inner wall surface of the opening 36a by a kind of capillary action. .

  For example, if the rubber wiper has a flat plate shape or a curved shape that is concave toward the wiping direction, the remaining ink tends to accumulate particularly in the wiping direction end area in the peripheral area of the nozzle. In this case, when the cloth wiper wipes the nozzle surface at a constant speed, the remaining ink accumulated in the wiping direction end area cannot be absorbed by the moving process. However, in the present embodiment, since the remaining ink R remains so as to be distributed substantially evenly in the wiping direction at the periphery of the nozzle peripheral region 37, most of the remaining ink R is absorbed by the cloth wiper 61 that moves at a constant speed. It is removed (FIG. 10 (d)).

  Further, as shown in FIG. 11B, since the pressing roller 67 does not exist at a position corresponding to the opening 36a, the cloth sheet 50 is prevented from being pushed deeply into the opening 36a. As a result, the cloth wiper 61 does not hit the nozzle peripheral region 37 or only hits it lightly. Since pigment particles are present in the ink absorbed by the cloth wiper 61, when the cloth sheet 50 being wiped moves while being pressed against the nozzle peripheral region 37, the nozzle peripheral region 37 is caused by the abrasive effect of the pigment particles. Takes damage. While such wiping is repeatedly performed, the liquid repellent film 42 in the nozzle peripheral region 37 gradually wears, and the liquid repellency of the nozzle peripheral region 37 decreases. When the ink spreads in the vicinity of the nozzle 38 due to the decrease in the liquid repellency, the ink droplets ejected from the nozzle 38 come into contact with each other to induce the flying bend of the ink droplets, resulting in a decrease in print image quality.

  However, in this embodiment, since the cloth sheet 50 is prevented from sliding on the nozzle peripheral region 37 in a pressed state, the liquid repellency of the nozzle peripheral region 37 is relatively high even if wiping is repeated. Maintained. As a result, the flying bend of the ink droplets ejected from the nozzle 38 hardly occurs, and a high print image quality can be obtained over a relatively long period.

  Further, since the protruding surface 40 has a lower liquid repellency than the nozzle peripheral region 37, the ink adhering to the protruding surface 40 is relatively easy to spread. For example, even if the remaining ink moves over the inner wall surface of the opening 36a toward the protruding surface 40 when the rubber wiper 59 is wiped off, the remaining ink that has moved onto the protruding surface 40 spreads wet. For this reason, this kind of ink on the protruding surface 40 is easily absorbed by the cloth wiper 61. If the liquid repellency of the projecting surface 40 is high, the ink that protrudes onto the projecting surface 40 when wiped with a rubber wiper does not spread out and exists on the periphery of the opening 36a. In this case, since the amount of ink absorbed by the portion corresponding to the periphery of the opening 36a of the cloth wiper 61 increases, the ink absorption performance of this portion gradually decreases as the cloth wiper 61 moves, and the remaining ink wiping performance decreases. To do.

  However, in this example, the ink on the protruding surface 40 having a lower liquid repellency than the nozzle peripheral region 37 easily spreads and the cloth wiper 61 can absorb the spread ink in a wide range. As a result, even if ink protrudes from the opening 36a toward the protruding surface 40 when the rubber wiper 59 is wiped, the remaining ink that protrudes can be effectively absorbed and removed.

According to the above embodiment, the following effects can be obtained.
(1) The wiping device 27 moves in contact with the first cleaning unit 60 having the non-absorbent rubber wiper 59 capable of wiping off ink adhering to the nozzle peripheral region 37 and the nozzle surface 39 and moves to the nozzle peripheral region 37. And a second cleaning unit 62 having a cloth wiper 61 capable of absorbing ink adhering to the protruding surface 40 which is an outer region other than the first cleaning unit 62. The ink on the nozzle peripheral region 37 is wiped off by the non-absorbing rubber wiper 59, and the ink on the protruding surface 40 is absorbed by the cloth wiper 61. As a result, it is possible to avoid ink dropping (dropping) from the projecting surface 40, ink transfer to the recording medium P approaching the projecting surface 40, and the like. Further, since the pigment is contained in the ink absorbed by the cloth wiper 61, there is a concern that the nozzle surface 39 is worn due to the abrasive effect of the pigment interposed between the cloth wiper 61 and the nozzle surface 39. However, although the cloth wiper 61 is pressed against the protruding surface 40 and efficiently absorbs ink, the cloth wiper 61 does not contact the nozzle peripheral area 37 or does not touch the nozzle peripheral area 37. It is hard to damage. For this reason, it is possible to suppress the occurrence of flying bends of ink droplets due to wear of the liquid repellent film 42 and to perform high-quality printing on the recording medium P.

  (2) After the ink on the nozzle peripheral region 37 is wiped with the rubber wiper 59, the cloth wiper 61 is brought into contact with the nozzle surface 39 to absorb the ink on the protruding surface 40. Therefore, the ink on the protruding surface 40 can be absorbed and removed, and the remaining ink R on the nozzle peripheral region 37 can be absorbed.

  (3) The periphery of the nozzle peripheral region 37 in the nozzle surface 39 is a protruding surface 40, and the cloth wiper 61 moves in contact with the protruding surface 40, thereby absorbing ink adhering to the protruding surface 40. Even if there are such irregularities on the nozzle surface, the adhered liquid can be wiped off with little remaining.

  (4) Since the protruding surface 40 has a lower liquid repellency than the nozzle peripheral region 37, the remaining ink that has moved from the nozzle peripheral region 37 over the step 41 to the protruding surface 40 when the rubber wiper 59 is wiped is left on the protruding surface 40. It is easy to spread with wet. For this reason, the cloth wiper 61 can absorb the ink on the protruding surface 40 efficiently.

  (5) The first cleaning unit 60 includes a rubber wiper 59, and the second cleaning unit 62 includes a belt-like cloth sheet 50 that abuts against the protruding surface 40. Therefore, the first cleaning unit 60 wipes the nozzle peripheral region 37 with the rubber wiper 59, and the second cleaning unit 62 brings the cloth sheet 50 into contact with the protruding surface 40 so that the ink attached to the protruding surface 40 is removed. Can be absorbed.

  (6) The second cleaning unit 62 includes a pressing roller 67 that presses the cloth sheet 50, and the pressing roller 67 is configured such that the pressing force on the nozzle peripheral region 37 of the cloth sheet 50 is weaker than the pressing force on the protruding surface 40. Is set to In particular, in this example, the cloth roller 50 is selectively pressed against the protruding surface 40 by providing the pressing roller 67 at a position corresponding to the protruding surface 40, so that the nozzle adhering to the protruding surface 40 can be absorbed efficiently. Damage to the peripheral region 37 can be reduced.

  (7) Since the wiping direction of the 1st cleaning part 60 and the wiping direction of the 2nd cleaning part 62 are the same, after the 1st cleaning part 60 wipes off the nozzle peripheral area, the remainder which exists along the wiping direction The second cleaning unit 62 can effectively wipe and absorb the ink.

  (8) Since the first cleaning unit 60 includes a rubber wiper having a convex shape in the wiping direction, the remaining ink R existing along the wiping path of the rubber wiper after the wiping is substantially uniform in the wiping direction. Distributed. Therefore, after that, when the second cleaning unit 62 moves while contacting the protruding surface 40 and absorbs ink adhering to the protruding surface 40, the ink remaining on both sides of the wiping path of the first cleaning unit 60 is Even if the second cleaning part 62 moves in contact with the protruding surface 40, it is absorbed efficiently.

The present invention is not limited to the above-described embodiment, and can be implemented in the following manner.
-It is good also as a wiping system by which the rubber wiper and the cloth wiper were comprised by the separate apparatus. For example, as shown in FIG. 12, the first cleaning device 81 (rubber wiper unit) having a plurality of rubber wipers 59 is different in the main scanning direction X with respect to the second cleaning device 82 (cloth wiper unit) (see FIG. 12). In the adjacent position). The first cleaning device 81 includes a slider 83 that holds the same number and the same number of rubber wipers 59 as the upper surface of the nozzle peripheral region 37 in a state of being movable in the wiping direction. The rubber wiper 59 has a curved shape that is convex toward the wiping direction. The first cleaning device 81 is driven using the electric motor 54 of the second cleaning device 82 as a common power source or a dedicated electric motor (not shown) as a power source. In a state where the liquid ejecting head 22 is disposed at the solid line position in the drawing, first, the plurality of rubber wipers 59 are moved in the wiping direction (nozzle row direction) by the power of the power source, so that the nozzle peripheral region 37 is wiped off. . After the wiping operation of the rubber wiper 59 is completed, the liquid ejecting head 22 moves to the two-dot chain line position in the figure, and then the wiper unit 46 moves in the wiping direction. 40 is wiped away. Even in this configuration, the nozzle peripheral region 37 can be wiped off by the rubber wiper 59 as in the above embodiment, and the ink on the protruding surface 40 is removed along with the ink remaining on the peripheral edge of the nozzle peripheral region 37 after the wiping. 61 can effectively absorb and remove.

  -You may comprise the press roller in the 2nd cleaning part 62 or the 2nd cleaning apparatus 82 with one roller. For example, as shown in FIG. 13, a single pressing roller 85 is used, and the pressing roller 85 is a step roller in which cylindrical large diameter portions 85a (convex portions) and small diameter portions 85b (concave portions) are alternately arranged in the axial direction. And The pressure roller 85 has a portion corresponding to the protruding surface 40 of the head cover 36 as a large diameter portion 85a and a portion corresponding to the nozzle peripheral region 37 as a small diameter portion 85b. It is supported. According to the cloth wiper 61, the cloth sheet 50 can be wiped while being pressed against the protruding surface 40, and the cloth sheet 50 is lightly applied to the nozzle peripheral region 37 with a small force that prevents contact or wear.

  The cloth wiper 61 of the second cleaning unit 62 or the second cleaning device 82 may have a non-movable configuration in which the cloth sheet 50 is pressed against the nozzle surface 39 to absorb ink. For example, as shown in FIG. 14, the cloth wiper 61 makes the cloth sheet 50 abut on the nozzle surface 39 and wipes the pressing roller 87 pressed against the surface of the cloth sheet 50 opposite to the nozzle surface 39 side. Move in the direction of the arrow in the figure. The support shaft 87a that rotatably supports the pressing roller 87 is supported in a state where it is biased toward the nozzle surface 39 via a spring (not shown) on a slider (not shown) that can move in a direction parallel to the wiping direction. Is done. The pressing roller 87 has the same multi-roller structure as that shown in FIGS. 6 and 8, or the same step roller as that shown in FIG. The cloth wiper 61 holds a region that can be in contact with the entire nozzle surface 39 of the cloth sheet 50 at a time in a posture parallel to the nozzle peripheral region 37, and moves the holding mechanism toward and away from the nozzle surface 39. A mechanism capable of moving up and down as much as possible, and a mechanism capable of feeding and winding to change the portion of the cloth sheet 50 held by the holding mechanism from a used one to an unused one.

  The liquid ejecting head may have a head structure having no step between a nozzle peripheral area wiped with a rubber wiper and an outer area other than the nozzle area. In this way, even if the surface to be wiped (nozzle surface) is a flat surface with the entire nozzle forming surface exposed and not uneven, the area around the nozzle can be wiped with the rubber wiper of the first cleaning unit, and the cloth wiper of the second cleaning unit The outer region other than the nozzle peripheral region can be wiped off while suppressing damage to the nozzle peripheral region.

The pressing unit may be a non-rotatable pressing member having a pressing surface corresponding to the nozzle surface instead of a rotatable pressing roller.
-The cloth wiper may be configured without a pressing roller. The ink adhering to the projecting surface can be absorbed and removed simply by bringing the cloth sheet into contact with the projecting surface. Alternatively, the ink may be absorbed and removed by using capillary force while contacting the ink adhering to the protruding surface without contacting the protruding surface.

  -In the said embodiment and the modification of FIG. 12, the order which drives a 1st cleaning part and a 2nd cleaning part for wiping may be reverse to the said embodiment. That is, first, the second cleaning unit may wipe the outer region (projecting surface as an example) other than the nozzle peripheral region on the nozzle surface with a cloth wiper, and then the first cleaning unit may wipe the nozzle peripheral region with a rubber wiper. .

  The wiping direction of the first cleaning unit and the second cleaning unit may be set equal to the main scanning direction X. Further, the nozzle surface 39 may be wiped off in the process in which the wiper unit 46 moves from the downstream side in the transport direction Y to the upstream side.

  -The wiping direction of the rubber wiper of the 1st cleaning part and the wiping direction of the cloth wiper of the 2nd cleaning part may differ. For example, it may be wiped in the nozzle row direction with a rubber wiper and wiped in a direction intersecting the nozzle row direction with a cloth wiper. The wiping direction between the rubber wiper and the cloth wiper may be reversed. For example, if the head cover opening is a single opening that exposes all nozzle rows, or if the head cover is not provided, ink residue will be generated even if wiped in the direction intersecting the nozzle rows with a rubber wiper. Hateful.

  The wiper unit of the second cleaning unit may be a fixed type fixed to the printer body, and the carriage may pass through the wiping position so that the nozzle surface slides on the wiper unit waiting at the wiping position.

  -The 2nd cleaning part which can absorb a liquid should just be cloth. The cloth refers to a large number of fibers processed into a plate shape, and may be a woven fabric, a knitted fabric, a lace, a felt, a non-woven fabric, or the like. Further, as the material of the cloth, for example, it is preferable to employ, for example, a polyester fiber that is a kind of relatively strong fiber material or a cupra that is a kind of fiber material having a low frictional resistance. The second cleaning unit may be other than cloth as long as it has liquid absorbability, and may be a porous resin material having absorbency such as sponge.

  -The rubber wiper of a 1st cleaning part is not limited to the curved shape which becomes convex toward a wiping direction, For example, flat form may be sufficient. In addition, it is not necessary to provide the same number of rubber wipers as the nozzle peripheral area. It may be made of any rubber. The rubber wiper can be made of urethane rubber or chloroprene rubber, but the first cleaning part may be made of a material other than rubber, such as an elastomer resin, as long as it does not absorb liquid. Further, the first cleaning unit can be adopted as long as it has a lower liquid absorbency than the second cleaning unit.

  Further, the cloth wiper may be brought into contact with the ink adhering to the nozzle peripheral region without being brought into contact with the nozzle peripheral region and absorbed and removed by using capillary force. In this case, the first cleaning unit may not be provided.

-It is not limited to a serial printer, but may be applied to a line printer and a page printer.
In each of the above embodiments, the medium is not limited to cloth or paper, and a resin film, a resin sheet, a metal sheet, or the like may be employed.

  The liquid ejecting apparatus is not limited to the printer 11 that ejects ink in the embodiment, and may be a liquid ejecting apparatus that ejects or ejects liquid other than ink. Note that the state of the liquid ejected as a minute amount of liquid droplets from the liquid ejecting apparatus includes a granular shape, a tear shape, and a thread-like shape. The liquid here may be any material that can be ejected from the liquid ejecting apparatus. 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 ). Further, not only a liquid as one state of a substance but also a substance in which particles of a functional material made of a solid such as a pigment or a metal particle are dissolved, dispersed or mixed in a solvent is included. Typical 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 ejecting apparatus, 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, or a color filter in a dispersed or dissolved form. There is a liquid ejecting apparatus for ejecting the liquid. Further, it may be a liquid ejecting apparatus that ejects a bio-organic matter used for biochip manufacturing, a liquid ejecting apparatus that ejects liquid as a sample that is used as a precision pipette, a printing apparatus, a micro dispenser, or the like. In addition, transparent resin liquids such as UV curable resin to form liquid injection devices that pinpoint lubricant oil onto precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. May be a liquid ejecting apparatus that ejects the liquid onto the substrate. Further, it may be a liquid ejecting apparatus that ejects an etching solution such as acid or alkali in order to etch a substrate or the like.

  DESCRIPTION OF SYMBOLS 11 ... Printer as an example of a liquid ejecting apparatus, 14 ... Conveyance motor, 20 ... Carriage motor, 22 ... Liquid ejecting head, 27 ... Wiping apparatus, 34 ... Nozzle row, 35 ... Nozzle formation surface, 38 ... Nozzle, 36 ... Head cover 36a ... Opening, 37 ... Nozzle peripheral region, 38 ... Nozzle, 39 ... Nozzle surface, 40 ... Projecting surface as an example of the outer region, 41 ... Step, 42 ... Liquid repellent film, 43 ... Recording head, 50 ... Strip shape Cloth sheet as an example of cloth, 54 ... electric motor, 59 ... rubber wiper, 60 ... first cleaning part, 61 ... cloth wiper, 62 ... second cleaning part, 67 ... pressing roller as an example of pressing part, 81 ... A first cleaning device as an example of the first cleaning unit, 82 ... a second cleaning device as an example of the second cleaning unit, 85 ... a pressing roller as an example of the pressing unit, 87 ... one of the pressing unit The pressing roller, P ... recording medium as.

Claims (8)

A liquid ejecting head that ejects liquid from a plurality of nozzles arranged on the nozzle surface;
A first cleaning unit capable of wiping off the liquid adhering to a nozzle peripheral region which is a region including the nozzle on the nozzle surface;
A second cleaning unit that is in contact with an outer region other than the nozzle peripheral region on the nozzle surface and is capable of absorbing liquid adhering to the outer region;
A liquid ejecting apparatus comprising:   The liquid ejecting apparatus according to claim 1, wherein after the liquid adhering to the nozzle peripheral region is wiped off by the first cleaning unit, the second cleaning unit is brought into contact with the outer region of the nozzle surface. .   The outer region includes a protruding surface protruding from the nozzle peripheral region around the nozzle peripheral region, and the second cleaning unit moves in contact with the protruding surface. The liquid ejecting apparatus described.   The liquid ejecting apparatus according to claim 3, wherein the protruding surface has lower liquid repellency than the peripheral area of the nozzle.   5. The liquid ejecting apparatus according to claim 1, wherein the first cleaning unit includes a rubber wiper, and the second cleaning unit includes a belt-shaped cloth that abuts against the outer region. 6. . The second cleaning unit includes a pressing unit capable of pressing the belt-shaped cloth against the nozzle surface side,
The liquid ejecting apparatus according to claim 5, wherein the pressing portion is set so that a pressing force of the cloth against the nozzle peripheral region is weaker than a pressing force with respect to the outer region.   The liquid ejecting apparatus according to claim 1, wherein a wiping direction of the first cleaning unit and a wiping direction of the second cleaning unit are the same.   The liquid ejecting apparatus according to claim 1, wherein the first cleaning unit includes a rubber wiper having a convex shape in a wiping direction.