JP5994289B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an ink jet recording apparatus that ejects ink of different colors from one ink jet head.

  Patent Document 1 discloses an ink jet recording apparatus that includes four ink jet heads that eject inks of different colors and two wipers that wipe each of the ejection surfaces of two different ink jet heads of the four ink jet heads. Is described. In this ink jet recording apparatus, each wiper wipes the ejection surfaces of the two heads after ink is forcibly discharged from the two heads, and removes ink adhering to the ejection surfaces.

JP 2009-248430 A

The present inventor has studied to adopt an ink jet head having an ejection surface on which a first ejection port and a second ejection port for ejecting different colors of ink are formed, and has found the following problems.
If one head forcibly discharges different colors of ink from the first and second ejection ports simultaneously, the inks are mixed on the ejection surface. In this state, when the ejection surface is wiped with a wiper (wiping member), the mixed color ink is pushed into the ejection port by the wiper. That is, ink color mixture occurs in the first and second ejection openings.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an ink jet recording apparatus capable of suppressing color mixing in each of the ejection ports on the ejection surface where the first ejection port and the second ejection port for ejecting different colors of ink are formed. Is to provide.

In the first aspect , the inkjet recording apparatus of the present invention is different from the plurality of first ejection ports that eject ink arranged at equal intervals in one direction and the ink ejected from the plurality of first ejection ports. An inkjet head having a discharge surface on which a plurality of second discharge ports arranged at equal intervals in the one direction are formed, and a first discharge formed by the plurality of first discharge ports A wiping member extending so as to straddle an outlet row and a second discharge port row formed by the plurality of second discharge ports, and the wiping member in contact with the discharge surface and along the discharge surface A moving mechanism that moves at least one of the wiping member and the ink jet head so as to move in one direction, and a plurality of first ejection ports by feeding ink to the ink jet head And a forced discharge mechanism capable of forcibly discharging ink from the plurality of second discharge ports, a first discharge operation for forcibly discharging ink only from the plurality of first discharge ports, and A first sequence that includes a first wiping operation that is performed after the first discharging operation and is an operation that wipes the ejection surface by relatively moving the wiping member, and ink from only the plurality of second ejection ports. A second discharge operation forcibly discharging, and a second sequence including a second wiping operation executed after the second discharging operation, which is an operation of wiping the ejection surface by relatively moving the wiping member. Control means for controlling the forcible discharge mechanism and the moving mechanism so that the relative movement direction of the wiping member with respect to the ejection surface in the first wiping operation is the second Pay Ru opposite der the direction of the relative movement in operation.
Further, according to a second aspect, the inkjet recording apparatus of the present invention includes a plurality of first ejection ports that eject ink arranged at equal intervals in one direction, and an ink ejected from the plurality of first ejection ports. Is formed by an inkjet head having an ejection surface that ejects ink of different colors and has a plurality of second ejection openings arranged at equal intervals in the one direction, and the plurality of first ejection openings. A wiping member extending so as to straddle one ejection port array and a second ejection port array formed by the plurality of second ejection ports, and the wiping member along the ejection surface while contacting the ejection surface And moving the at least one of the wiping member and the inkjet head so as to move in the one direction, and feeding the ink to the inkjet head. A forcible discharge mechanism capable of selectively discharging ink from an outlet and the plurality of second discharge ports; a first discharge operation for forcibly discharging ink only from the plurality of first discharge ports; and , A first sequence that includes a first wiping operation that is performed after the first discharging operation, and an operation that wipes the ejection surface by relatively moving the wiping member, and ink from only the plurality of second ejection ports. A second sequence that includes a second discharge operation that forcibly discharges the liquid and a second wiping operation that is performed after the second discharge operation by wiping the discharge surface by relatively moving the wiping member. Control means for controlling the forced discharge mechanism and the moving mechanism. The inkjet head is connected to each of the plurality of first ejection ports and the plurality of second ejection ports, and applies ejection energy to the plurality of pressure chambers filled with ink and the ink in the pressure chambers. And an energy applying unit that ejects ink from the plurality of first ejection ports and the plurality of second ejection ports, and the control unit performs the first wiping operation when the first wiping operation is performed. A second flushing operation for ejecting ink from the plurality of first ejection ports when the second wiping operation is performed so that a first flushing operation for ejecting ink from the plurality of second ejection ports is performed. The energy applying means is controlled so that
Further, according to a third aspect, the inkjet recording apparatus of the present invention includes a plurality of first ejection ports that eject ink arranged at equal intervals in one direction, and an ink ejected from the plurality of first ejection ports. Is formed by an inkjet head having an ejection surface that ejects ink of different colors and has a plurality of second ejection openings arranged at equal intervals in the one direction, and the plurality of first ejection openings. A wiping member extending so as to straddle one ejection port array and a second ejection port array formed by the plurality of second ejection ports, and the wiping member along the ejection surface while contacting the ejection surface And moving the at least one of the wiping member and the inkjet head so as to move in the one direction, and feeding the ink to the inkjet head. A forcible discharge mechanism capable of selectively discharging ink from an outlet and the plurality of second discharge ports; a first discharge operation for forcibly discharging ink only from the plurality of first discharge ports; and , A first sequence that includes a first wiping operation that is performed after the first discharging operation, and an operation that wipes the ejection surface by relatively moving the wiping member, and ink from only the plurality of second ejection ports. A second sequence that includes a second discharge operation that forcibly discharges the liquid and a second wiping operation that is performed after the second discharge operation by wiping the discharge surface by relatively moving the wiping member. Control means for controlling the forced discharge mechanism and the moving mechanism, and a first pressure on the first discharge port of the wiping member is a second pressure on the second discharge port of the wiping member. 2 pressures A posture changing mechanism that changes the posture of at least one of the inkjet head and the wiping member so that a first state larger than the first pressure and a second state in which the second pressure is larger than the first pressure can be taken. And. And the said control means controls the said attitude | position change mechanism so that it may take the said 1st state in the said 1st wiping operation | movement, and to take the said 2nd state in the said 2nd wiping operation | movement.

  According to the ink jet recording apparatus of the present invention, after the ink is forcibly discharged only from the first or second discharge port, the discharge surface is wiped off. For this reason, ink color mixing on the ejection surface is suppressed. As a result, in each wiping operation, the mixed ink is hardly pushed into the first and second ejection ports, and the color mixture can be suppressed in each ejection port.

It is a schematic side view which shows the internal structure of the inkjet printer by one Embodiment of this invention. It is a top view which shows the head main body of the head contained in the printer of FIG. FIG. 3 is an enlarged view showing a region surrounded by an alternate long and short dash line in FIG. 2. (A) is the fragmentary sectional view along the IV-IV line shown in FIG. 3, (b) is an enlarged view which shows the area | region enclosed with the dashed-dotted line of FIG. 4 (a). It is a top view of a head, a wiping mechanism, and a cleaning member. It is the elements on larger scale of a discharge surface. (A) is a situation figure when a wiper takes a 1st state, (b) is a situation figure when a wiper takes a 2nd state. It is a functional block diagram of the control part shown in FIG. FIG. 2 is a flowchart relating to an example of a maintenance operation executed by a control unit of the printer in FIG. 1. It is an operation | movement condition figure for demonstrating an example of a maintenance operation | movement. It is a figure which shows the ink wiping condition of the discharge surface in 1st wiping operation | movement. It is a flowchart regarding the maintenance operation when a jam occurs.

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

  First, an overall configuration of an inkjet printer 101 according to an embodiment of the present invention will be described with reference to FIG.

  The printer 101 has a rectangular parallelepiped housing 101a. A paper discharge unit 4 is provided on the top of the casing 101a. The internal space of the housing 101a can be divided into spaces A, B, and C in order from the top. In the spaces A and B, a paper conveyance path from the paper supply unit 23 toward the paper discharge unit 4 is formed, and the paper P is conveyed along the thick black arrows shown in FIG. In the space A, image recording on the paper P and conveyance of the paper P to the paper discharge unit 4 are performed. In the space B, the paper P is fed to the conveyance path. From the space C, ink is supplied to the two inkjet heads 1 in the space A, and the pretreatment liquid is supplied to the treatment liquid application mechanism 2 in the space A.

  In the space A, two ink head heads (hereinafter referred to as heads) 1, a treatment liquid application mechanism 2, a transport mechanism 40, two guide portions 10a and 10b for guiding the paper P, two paper sensors 26 and 27, A head lifting mechanism 33 (see FIG. 8), a wiping mechanism 50 (see FIG. 5), two sets of cleaning members (cleaning means: see FIG. 5) 70, a cleaner unit 37, a control unit 100, and the like are arranged.

  From each head 1, two colors of ink are ejected. Yellow and magenta inks are ejected from the head 1 on the upstream side in the paper transport direction. Cyan and black inks are ejected from the downstream head 1. These two heads 1 have the same structure, are arranged at a predetermined interval in the sub-scanning direction, and are supported by the casing 101a via the head holder 5. The lower surface of each head 1 is a discharge surface 1a in which a plurality of discharge ports 108 (see FIG. 3) are arranged.

  The head 1 includes a reservoir unit (not shown), a flexible printed wiring board (FPC: not shown), and a control board (not shown) in addition to the head body 3 (see FIG. 2) including the flow path unit 9 and the actuator unit 21. Etc. are laminated bodies. The signal adjusted by the control board is converted into a drive signal by the driver IC on the FPC and output to the actuator unit 21. When the actuator unit 21 is driven, the ink supplied from the reservoir unit is ejected from the ejection port 108.

  Next, the head 1 will be described in detail with reference to FIGS. In FIG. 3, for convenience of explanation, the pressure chamber 110, the aperture 112, and the discharge port 108 that are to be drawn by broken lines below the actuator unit 21 are drawn by solid lines.

  As shown in FIG. 4A, the flow path unit 9 is a laminated body in which nine stainless steel plates 122 to 130 are laminated. A total of ten ink supply ports 105b are opened on the upper surface of the flow path unit 9, as shown in FIG. As shown in FIGS. 2 to 4, a manifold channel 105 having an ink supply port 105 b as one end and a plurality of sub-manifold channels 105 a are formed inside the channel unit 9. The sub-manifold channel 105a branches from the manifold channel 105 and extends along the main scanning direction, and connects the manifold channels 105 connected to the ink supply ports 105b adjacent to each other in the main scanning direction. That is, the five ink supply ports 105b arranged in the main scanning direction communicate with each other and do not communicate with the other five ink supply ports 105b belonging to other columns. Thus, in the present embodiment, the ink supply port 105b of the flow path unit 9 is divided for each column, and different colors of ink are supplied from the reservoir unit to each column.

  As shown in FIG. 4A, a plurality of individual ink channels 132 are connected to each sub-manifold channel 105a. The individual ink channel 132 extends from the outlet of the sub-manifold channel 105 a to the ejection port 108 through the aperture 112 and the pressure chamber 110. The lower surface of the flow path unit 9 is a discharge surface 1a, and a large number of discharge ports 108 are arranged in a matrix.

  As shown in FIGS. 5 and 6, two ejection regions 91 and 92 are defined on the ejection surface 1a. In FIG. 6, an ejection area 91 is an area in which a plurality of ejection openings 108 for ejecting ink (first ejection opening: indicated by black circles) are gathered (area including the ejection openings 108 indicated by black circles). Is a region where a plurality of ejection ports 108 (second ejection ports: indicated by white circles) that eject ink of a different color from the ejection region 91 are gathered (a region including the ejection ports 108 indicated by white circles). As shown in FIG. 2, each of the discharge regions 91 and 92 is configured by a plurality of discharge port groups gathered in a trapezoidal outer shape and arranged in a staggered arrangement in the main scanning direction. In addition, in the ejection areas 91 and 92, part of the areas 91a and 92a overlap each other in the sub-scanning direction. In other words, the ejection port arrays 109a and 109b in the portions 91a and 92a of the ejection regions 91 and 92 are arranged close to each other. Further, most of the discharge area 91 is downstream of the discharge area 92 in the transport direction D on the discharge surface 1a.

  As shown in FIG. 6, the discharge ports 108 in the discharge regions 91 and 92 are arranged at a predetermined distance in the main scanning direction. In the present embodiment, they are arranged at a distance corresponding to 300 dpi. In the sub-scanning direction, one ejection port 108 in the ejection region 91 is disposed so as to overlap with one ejection port 108 in the ejection region 92. The printer 101 is a color printer, and when another head 1 is also added, one ejection port 108 overlaps with the three ejection ports 108 in the sub-scanning direction, and ejects ink of different colors.

  The plurality of ejection openings 108 belonging to the ejection area 91 are arranged so as to constitute 16 ejection opening arrays 109a. The ejection port array 109a extends along the main scanning direction. The plurality of ejection openings 108 belonging to the ejection area 92 are also arranged to form 16 ejection opening arrays 109b. The ejection port array 109b extends along the main scanning direction.

  Two reservoirs 22a are connected to the reservoir unit via a pump 38, and two colors of ink are supplied. The reservoir unit is a channel member in which an ink channel is formed for each color. Ink for the flow path unit 9 is stored in the reservoir of the ink flow path. As shown in FIGS. 2 to 4, the ink in the reservoir unit is supplied to the flow path unit 9 from the ink supply port 105 b. At this time, ink of the same color is supplied from the reservoir unit to the ink supply port 105b for each column.

  The pump 38 is disposed for each cartridge 22a and forcibly supplies ink to the flow path unit 9 via the reservoir unit. In FIG. 8, one of the pumps 38 is shown.

  Next, the actuator unit 21 will be described. The actuator unit 21 is fixed to the upper surface of the flow path unit 9. As shown in FIG. 2, each of the four actuator units 21 has a trapezoidal planar shape, and is arranged in a staggered manner in the main scanning direction so as to avoid the ink supply ports 105b.

  The actuator unit 21 is made of lead zirconate titanate (PZT) ceramic having ferroelectricity, and is composed of three piezoelectric layers 161 to 163 as shown in FIG. 4B. The uppermost piezoelectric layer 161 is polarized in the thickness direction and sandwiched between the individual electrodes 135 on the upper surface and the common electrode 134 on the entire lower surface. Most of the individual electrode 135 faces the pressure chamber 110, and a part of the outside of the pressure chamber is connected to the individual land 136 in a plan view. This form is formed for each pressure chamber 110, and each serves as an individual actuator. That is, the actuator unit 21 has a number of actuators corresponding to the pressure chambers 110, and each selectively applies ejection energy to the ink in the pressure chambers 110.

  Here, a driving method of the actuator unit 21 will be described. Each actuator is a so-called unimorph type actuator. A portion sandwiched between both electrodes 134 and 135 of the piezoelectric layer 161 contracts in a direction (plane direction) perpendicular to the polarization direction when an electric field is applied in the polarization direction. At this time, since a strain difference is generated between the lower piezoelectric layers 162 and 163, a portion sandwiched between the individual electrode 135 and the pressure chamber 110 protrudes toward the pressure chamber 110 side. Along with this, pressure (discharge energy) is applied to the ink in the pressure chamber 110, and ink droplets are discharged from the discharge ports 108.

  The treatment liquid application mechanism 2 includes a roller 2a, a support portion 2b that rotatably supports the roller 2a, and a solenoid 2c. The solenoid 2c has a movable iron core, and the movable iron core and the support portion 2b are fixed. The movable iron core is configured to be movable in the vertical direction. The roller 2a includes a shaft and a cylindrical sponge that covers the outer peripheral surface of the shaft, and the pretreatment liquid of the cartridge 22b is supplied to the sponge by a treatment liquid supply mechanism (not shown). The roller 2 a is usually disposed away from the transport belt 43. When printing is performed on the paper P, the solenoid 2 c is driven by the control unit 100, and the roller 2 a comes into contact with the transport belt 43. As a result, the paper P supported by the transport belt 43 and the roller 2a come into contact with each other, and the pretreatment liquid is applied to the printing surface of the paper P. In the present embodiment, the pretreatment liquid is applied to the entire surface of the paper P.

  The transport mechanism 40 includes two belt rollers 41 and 42, a transport belt 43, a platen 46, a nip roller 47, and a peeling plate 45. The conveyor belt 43 is an endless belt wound between the rollers 41 and 42. The platen 46 is disposed to face the roller 2a and the two heads 1, and supports the upper loop of the conveyor belt 43 from the inside. The belt roller 42 is a driving roller and causes the transport belt 43 to travel. The belt roller 42 is rotated clockwise in FIG. 1 by a motor (not shown). The belt roller 41 is a driven roller and is rotated by the travel of the transport belt 43. The nip roller 47 presses the paper P transported from the paper feeding unit 23 against the outer peripheral surface of the transport belt 43. The paper P is held on the transport belt 43 by the silicon layer (weakly adhesive outer peripheral surface coating layer) and transported toward the head 1. The peeling plate 45 peels the conveyed paper P from the transport belt 43 and guides it to the paper discharge unit 4 on the downstream side.

  The two guide portions 10a and 10b are arranged with the transport mechanism 40 interposed therebetween. The guide unit 10a on the upstream side in the transport direction includes two guides 31a and 31b and a feed roller pair 32, and connects the paper feed unit 23 and the transport mechanism 40. The image recording paper P is transported toward the transport mechanism 40. The guide unit 10b on the downstream side in the transport direction has two guides 33a and 33b and two feed roller pairs 34 and 35, and connects the transport mechanism 40 and the paper discharge unit 4. The paper P after image recording is conveyed toward the paper discharge unit 4.

  As shown in FIG. 1, the two paper sensors 26 and 27 are arranged at positions where the two heads 1 are sandwiched from both sides in the transport direction. The upstream sensor 26 detects the leading edge of the paper P, and the ink ejection timing is determined by the detection signal. The downstream sensor 27 also detects the leading edge of the paper P, and constitutes a jam detection mechanism (described later) together with the sensor 26.

  The head lifting mechanism 33 moves the head holder 5 up and down. As a result, the two heads 1 move between the printing position and the retracted position. At the printing position, as shown in FIG. 1, the two heads 1 are positioned at the lower end of the moving range, and face the conveying belt 43 at an interval suitable for printing. In the retracted position, the two heads 1 are positioned at the upper end of the moving range and are greatly separated from the transport belt 43. The wiping position is between the printing position and the retracted position (see FIG. 10B), and the ejection surface 1a is wiped by the wiper 51 described later. In the wiping position and the retracted position, the wiper 51 can move in the space between the two heads 1 and the conveyor belt 43.

  As shown in FIGS. 5 and 7, the wiping mechanism 50 includes a wiper unit 55 and a wiper unit moving mechanism 56 that moves the wiper unit 55. The wiper unit moving mechanism 56 reciprocates the wiper unit 55 in the main scanning direction. The wiper unit 55 wipes the ejection surface 1a as it moves. The wiping mechanism 50 is provided for each head 1.

  The wiper unit 55 includes a wiper (wiping member) 51 and a support portion 52. The wiper 51 is made of a plate-like elastic member (for example, rubber). The wiper 51 is slightly longer than the ejection surface 1a in the sub scanning direction. The wiper 51 extends across the ejection port array in the ejection region 91 and the ejection port array in the ejection region 92 in the sub-scanning direction.

  As shown in FIG. 5, the wiper 51 extends in a direction crossing the main and sub-scanning directions. In other words, the wiper 51 is disposed to be inclined with respect to the main and sub scanning directions. The wiper 51 has a first surface 51a along the extending direction of the wiper, and a second surface 51b opposite to the first surface 51a. Further, the wiper 51 moves the wiper unit 55 by the wiper unit moving mechanism 56 so that the first standby position (home position) (the position shown in FIGS. 5 and 10A) and the second standby position (FIG. 10 (c)). The wiper unit 55 is moved downward (wiping direction Y1) in FIG. 5 from the first standby position toward the second standby position in a first wiping operation described later. Then, after passing through the ejection surface 1a, it is temporarily waited at the second standby position. In the first wiping operation, the wiper 51 is moved while the tip of the wiper 51 is in contact with the discharge surface 1 a, so that the discharge surface 1 a is wiped by the wiper 51. Note that, as shown in FIG. 11, in the first wiping operation, the first surface 51a of the wiper 51 is located downstream of the second surface 51b in the wiping direction Y1. That is, in the first wiping operation, the ink attached to the ejection surface 1 a is wiped off by the first surface 51 a of the wiper 51. In the first wiping operation, the wiper 51 is in contact with (opposed to) the discharge port array 109a formed by the discharge port (first discharge port) 108 in the discharge region 91 (in the sub-scanning direction in FIG. The right portion) extends so as to be upstream of the wiping direction Y1 from the portion facing the discharge port array 109b formed by the discharge port (first discharge port) 108 of the discharge region 92. Moreover, in the 2nd wiping operation | movement mentioned later, it moves to upper direction in FIG. 5 (wiping direction Y2) toward a 1st standby position from a 2nd standby position. Also in this second wiping operation, the wiper 51 is moved while its tip is in contact with the discharge surface 1 a, so that the discharge surface 1 a is wiped by the wiper 51. In the second wiping operation, the second surface 51b of the wiper 51 is located downstream of the first surface 51a in the wiping direction Y2. That is, in the second wiping operation, the ink attached to the ejection surface 1 a is wiped off by the second surface 51 b of the wiper 51. In the second wiping operation, the wiper 51 is in contact with (opposed to) the discharge port array 109b formed by the discharge port (second discharge port) 108 in the discharge region 92 (in the sub-scanning direction, more than the center of the wiper 51. The left portion in FIG. 5 extends so as to be upstream in the wiping direction Y2 from the portion facing the discharge port array 109a formed by the discharge ports 108 in the discharge region 91.

  Further, the wiper 51 has two projecting portions 53a and 53b. The protruding portion 53a is formed to protrude from the first surface 51a in the wiping direction Y1. The protrusion 53b is formed to protrude from the second surface 51b in the wiping direction Y2. These protrusions 53a and 53b extend in the vertical direction from the upper end to the lower end of the wiper 51 on each surface 51a and 51b, as shown in FIG. With respect to the sub-scanning direction, as shown in FIG. 5, the tip of the protruding portion 53 a is slightly outside the outermost end of the discharge region 91 on the discharge region 92 side (discharge region 92 side). That is, in FIG. 6, the tip of the protrusion 53a is the discharge port row 109a at the outermost end of the discharge region 91 on the discharge region 92 side, and of the two discharge port rows 109b adjacent to the discharge port row 109a. It is arranged so as to be able to come into contact with the discharge surface 1a region between the discharge port array 109b separated from the discharge region 91. With respect to the sub-scanning direction, the distal end of the protrusion 53b is slightly outside the outermost end of the discharge region 92 on the discharge region 91 side (discharge region 91 side). That is, in FIG. 6, the discharge port array 109b located at the outermost end of the discharge region 92 on the discharge region 91 side and the discharge port away from the discharge region 92 of the two discharge port columns 109a adjacent to the discharge port column 109b. The region of the discharge surface 1a between the outlet row 109a and the tip of the protruding portion 53b are arranged so as to be in contact with each other.

  The support part 52 has a rectangular parallelepiped shape, and the wiper 51 is erected on the upper surface. The support part 52 is slightly longer than the wiper 51 in the sub-scanning direction. As shown in FIG. 5, a hole 54a penetrating in the main scanning direction is formed at both ends of the support portion 52, and a female screw is formed in one hole 54a.

  The wiper unit moving mechanism 56 includes a pair of guides (for example, round bars) 57 extending in the main scanning direction, a drive motor 59 (see FIG. 8), and a guide support mechanism (contact pressure changing mechanism) 58. The pair of guides 57 are inserted into the holes 54a and sandwich the head 1 from both sides in the sub-scanning direction. One guide 57 has a male screw formed on the outer peripheral surface thereof and is screwed into the female screw of the hole 54a. This guide 57 receives the rotational force of the drive motor 59. The inner peripheral surface of the other hole 54a slides on the other guide 57.

  As shown in FIG. 10, the wiper unit 55 reciprocates along the guide 57 by forward and reverse rotations of the drive motor 59. As shown in FIG. 10B, in the first wiping operation, the wiper 51 moves from the first standby position (position shown in FIG. 10A) to the right in the drawing with respect to the head 1 in the wiping position. Then, the ejection surface 1a is wiped off. As shown in FIG. 10D, in the second wiping operation, the wiper 51 moves from the second standby position (position shown in FIG. 10C) to the left in the figure with respect to the head 1 in the wiping position. Then, the ejection surface 1a is wiped off.

  The guide support mechanism (posture changing mechanism) 58 includes four support portions 58a that support both ends of the pair of guides 57 in the main scanning direction, and four solenoids 58b. The solenoid 58b has a movable iron core, and the movable iron core and the support portion 58a are fixed. The movable iron core is configured to be movable in the vertical direction. The guide support mechanism 58 changes the vertical height of the guide 57 to change the pressure on the discharge surface 1a of the wiper 51 in each wiping operation.

  Specifically, when the wiper unit 55 is in the first standby position, as shown in FIG. 7A, the guide 57 on the right side is disposed at a position slightly higher than the guide 57 on the left side and protrudes. The four solenoids 58b are controlled by the control unit 100 so that the upper end of the part 53a is just in contact with the discharge surface 1a. As a result, the straight line connecting the centers of the pair of guides 57 forms an acute angle θ with respect to the horizontal line, and the tip of the wiper 51 is tilted to the left (first state). For this reason, in the first wiping operation, the pressure (second pressure) applied to the discharge port 108 in the discharge region 92 of the wiper 51 is lower than the pressure (first pressure) applied to the discharge port 108 in the discharge region 91 of the wiper 51. . More specifically, at the tip end portion of the wiper 51 (the upper end portion of the first surface 51a), the region on the right side in FIG. 7A from the protrusion 53a (the region facing the discharge region 91) is in contact with the discharge surface 1a. At the same time, it is inclined so as to approach the ejection surface 1a as it goes to the right side in the figure. On the other hand, the region on the left side in FIG. 7A from the protrusion 53a (the region facing the discharge region 92) moves away from the discharge surface 1a toward the left side in the drawing. In other words, the amount of deflection of the wiper 51 when the wiper 51 comes into contact with the ejection surface 1a increases toward the right side in FIG.

  When the wiper unit 55 is in the second standby position, as shown in FIG. 7B, the guide 57 on the left side is disposed at a position slightly higher than the guide 57 on the right side, and the upper end of the protrusion 53b is The four solenoids 58b are controlled by the control unit 100 so as to be in contact with the discharge surface 1a. As a result, the straight line connecting the centers of the pair of guides 57 forms an acute angle θ with respect to the horizontal line, and the tip of the wiper 51 is tilted to the right (second state). For this reason, in the second wiping operation, the pressure (second pressure) on the discharge port 108 in the discharge region 91 of the wiper 51 is lower than the pressure (second pressure) on the discharge port 108 in the discharge region 92 of the wiper 51. . More specifically, in the front end portion of the wiper 51 (the upper end portion of the second surface 51b), the region on the left side in FIG. 7B (region facing the discharge region 92) from the protrusion 53b is in contact with the discharge surface 1a. At the same time, it approaches the ejection surface 1a as it goes to the left in the figure. On the other hand, the region on the right side in FIG. 7B from the protrusion 53b (the region facing the discharge region 91) moves away from the discharge surface 1a toward the right side in the drawing. In other words, the amount of deflection of the wiper 51 when the wiper 51 comes into contact with the ejection surface 1a increases toward the left side in FIG. 7B.

  As shown in FIG. 5, the cleaning member 70 is disposed for each head 1 and has a pair of absorbers 70a and 70b. The pair of absorbers 70a and 70b sandwich the corresponding head 1 in the main scanning direction. Each absorber 70a, 70b has substantially the same length as the wiper 51 in the sub-scanning direction. Moreover, each absorber 70a, 70b is comprised from the porous member (for example, sponge). The lower surfaces of the absorbers 70a and 70b are disposed slightly lower than the ejection surface 1a of the head 1 at the wiping position. As a result, the wiper 51 passes under the absorbers 70a and 70b, so that the entire tip of the wiper 51 comes into contact with the ink and the ink attached thereto can be cleaned.

  The cleaner unit 37 includes a blade 37b and a moving mechanism 37c (see FIG. 8), and cleans the outer peripheral surface of the transport belt 43. As shown in FIG. 1, the cleaner unit 37 is disposed on the lower right side of the conveyor belt 43 and is opposed to the belt roller 42. The blade 37b is composed of a plate-like elastic member (for example, rubber), and can contact the conveyor belt 43 over the entire width. The moving mechanism 37 c brings the blade 37 b into contact with the outer peripheral surface of the conveyor belt 43. In the cleaning operation, dirt is scraped off from the outer peripheral surface by the blade 37b.

  In the space B, a paper feeding unit 23 is arranged. The paper feed unit 23 includes a paper feed tray 24 and a paper feed roller 25. Among these, the paper feed tray 24 is detachable from the housing 101a. The paper feed tray 24 is a box that opens upward, and can store a plurality of papers P. The paper feed roller 25 sends out the uppermost paper P in the paper feed tray 24.

  Here, the sub-scanning direction is a direction parallel to the paper transport direction D transported by the transport mechanism 40, and the main scanning direction is a direction parallel to the horizontal plane and perpendicular to the sub-scanning direction.

  In the space C, five cartridges 22a and 22b are detachably arranged with respect to the housing 101a. The four cartridges 22a contain any one of magenta, cyan, yellow, and black ink. Each cartridge 22a is connected to the head 1 via a tube (not shown) and a pump 38 (see FIG. 8). Each pump 38 is in a stopped state except when the ink is forcibly sent to the head 1, and does not hinder ink supply to the head 1. The cartridge 22b contains a colorless and transparent pretreatment liquid. The cartridge 22b is connected to the roller 2a via a tube and a pump as a processing liquid supply mechanism. The processing liquid supply mechanism supplies a predetermined amount of pretreatment liquid to the roller 2 a when printing is performed under the control of the control unit 100.

  In general, a pretreatment liquid for aggregating pigment pigments is used for pigment inks, and a pretreatment liquid for precipitating dye pigments is used for dye inks. The material of the pretreatment liquid can be appropriately selected from a liquid containing a polyvalent metal salt such as a cationic polymer or a magnesium salt. When such a pretreatment liquid and ink are mixed, a polyvalent metal salt or the like acts on a dye or pigment that is a colorant of the ink, and a hardly soluble metal complex (lumps) or the like is formed by aggregation or precipitation.

  Next, the control unit 100 will be described with reference to FIG. The control unit 100 includes a CPU (Central Processing Unit), a program executed by the CPU and a ROM (Read Only Memory) that stores data used for these programs in a rewritable manner, and temporarily stores data when the program is executed. RAM (Random Access Memory). Each functional unit constituting the control unit 100 is constructed by cooperation of these hardware and software in the ROM. As shown in FIG. 8, the control unit 100 includes a transport control unit 141, an image data storage unit 142, a head control unit 143, a jam detection unit 144, a processing liquid control unit 145, and a maintenance control unit 150. Have.

  The transport control unit 141 is configured so that the paper P is transported at a predetermined speed along the transport direction based on the print command received from the external device, and the pair of feed rollers 32, 34, 35, and Each operation of the transport mechanism 40 is controlled. The image data storage unit 142 stores image data (ink ejection data) included in a print command from an external device.

  The head controller 143 controls the head 1 so as to eject ink in the recording operation and the flushing operation. In the recording operation, the head control unit 143 controls ink ejection from the head 1 so as to eject ink onto the paper P based on the image data stored in the image data storage unit 142. The ink ejection timing is determined based on detection of the leading edge of the paper P by the paper sensor 26, and is a time when a predetermined time has elapsed after the paper P is detected. The predetermined time referred to here is the distance along the transport path from the leading edge of the paper P to the discharge port 108 at the most upstream when the paper sensor 26 detects the leading edge of the paper P for each head 1. The time divided by the conveyance speed of the paper P.

  In the flushing operation, the head controller 143 controls ink ejection from the head 1 so that ink is ejected toward the transport belt 43 based on pre-stored flushing data. The flushing operation includes first to third flushing operations. In the first flushing operation, the actuator is driven and ink is ejected only from the ejection port 108 in the ejection region 92. That is, in the first flushing operation, ink is not ejected from the ejection port 108 in the ejection area 91. In the second flushing operation, the actuator is driven and ink is ejected only from the ejection port 108 of the ejection area 91. That is, in the second flushing operation, ink is not ejected from the ejection port 108 in the ejection region 92. These first and second flushing operations are executed such that ink is ejected in order from the ejection port 108 immediately after the wiper 51 passes in each wiping operation. The ink ejection timings in the first and second flushing operations are set based on actually measured values (time data) obtained by executing the wiping operation a plurality of times in advance. Specifically, the time for the wiper 51 to move from each standby position at a predetermined speed and pass through each ejection port 108 is measured. This time measurement is performed a plurality of times. In each ejection port 108, the ink ejection timing is set so that ink is ejected when the longest time has elapsed among the time until the wiper 51 passes through the ejection port 108. As a result, ink is not discharged until the wiper 51 passes through the discharge port 108, and ink is reliably discharged immediately after passing through the discharge port 108. In the third flushing operation, the actuator is driven and ink is ejected from all the ejection ports 108. Ink ejection by each flushing operation is performed based on flushing data (data different from image data).

  The jam detection unit 144 detects that a jam has occurred between the ejection surface 1a and the conveyor belt 43 when the detection interval of the leading edge of the paper P by the two paper sensors 26 and 27 exceeds a predetermined time. The predetermined time here is a time obtained by dividing the transport distance between the two paper sensors 26 and 27 by the transport speed of the paper P. When a jam is detected by the jam detection unit 144, the head control unit 143 and the conveyance control unit 141 stop the ejection of ink and the conveyance of the paper P. When the jam detection unit 144 detects a jam, the control unit 100 controls the buzzer 28 (see FIG. 8) so as to emit a sound. The jam detecting unit 144 and the paper sensors 26 and 27 constitute a jam detecting mechanism.

  The processing liquid control unit 145 controls the processing liquid coating mechanism 2 based on the print command received from the external device, and controls the separation / contact operation of the roller 2 a with respect to the transport belt 43. Further, the processing liquid control unit 145 controls a pump (processing liquid supply mechanism) (not shown) based on a print command received from an external device, and supplies a predetermined amount of preprocessing liquid to the roller 2a.

  The maintenance control unit 150 controls the transport mechanism 40, the head lifting mechanism 33, the wiper unit moving mechanism 56, the moving mechanism 37c, and the pump 38 in maintenance operations such as each purge operation, each wiping operation, and cleaning operation. . In the maintenance operation, preparation for recovery of ink ejection characteristics of the head 1 and recording is performed. The purge operation includes first to third purge operations. In the first purge operation, the pump 38 is driven and ink is forcibly discharged only from the discharge port 108 of the discharge region 91. In the second purge operation, the pump 38 is driven and ink is forcibly discharged only from the discharge port 108 of the discharge region 92. In the third purge operation, all the pumps 38 are driven and ink is forcibly discharged from all the ejection ports 108. The wiping operation includes a first wiping operation and a second wiping operation. The first wiping operation is performed after the first purge operation, and the ejection surface 1 a is wiped by the wiper 51. The second wiping operation is performed after the second purge operation, and the ejection surface 1 a is wiped by the wiper 51. In this way, ink and foreign matters remaining on the ejection surface 1a are removed. In the cleaning operation, the conveyor belt 43 is wiped by the cleaner unit 37.

  Next, an example of the maintenance operation of the printer 101 will be described with reference to FIGS.

  First, as shown in FIG. 9, the control unit 100 receives a purge command other than jam detection (for example, when the print standby time is a predetermined time or more) (F1). When the purge command is received, the maintenance control unit 150 controls the head lifting mechanism 33 to position the head 1 at the printing position. Next, the maintenance control unit 150 executes the first sequence, and subsequently executes the second sequence. The first sequence refers to performing the first wiping operation and the first flushing operation after executing the first purge operation, and cleaning the wiper 51 with the absorber 70a before shifting to the second sequence. The second sequence refers to performing the second wiping operation and the second flushing operation after performing the second purge operation, and then cleaning the wiper 51 with the absorber 70b.

  Specifically, in the first sequence, the maintenance control unit 150 controls the pump 38 to discharge ink onto the transport belt 43 only from the ejection openings 108 in the ejection area 91 (see FIG. 10A). F2: First purge operation). In the purge operation in the present embodiment, the two pumps 38 corresponding to each head 1 are selectively driven, a predetermined amount of ink in the cartridge 22a is forcibly sent to the head 1, and ink is ejected from the ejection port 108. Is discharged. At this time, the ink discharged from the discharge port 108 in the discharge region 91 has a lightness smaller than the ink discharged from the discharge port 108 in the discharge region 92. That is, in the first purge operation, magenta ink is discharged from the head 1 upstream in the transport direction, and black ink is discharged from the downstream head 1.

  Next, as shown in FIG. 10B, the maintenance control unit 150 controls the head lifting mechanism 33 to move the head 1 to the wiping position. Thereafter, the maintenance control unit 150 controls the drive motor 59 to move the wiper unit 55 from the first standby position in the wiping direction Y1 as shown in FIG. 10B (F3: first wiping operation). . Accordingly, the wiper 51 moves in the wiping direction Y1 while being in contact with the discharge surface 1a, and the discharge surface 1a is wiped by the wiper 51. Here, as shown in FIG. 11, since the wiper 51 is inclined with respect to the direction of relative movement with respect to the ejection surface 1a, in the first wiping operation, the ink discharged by the first purge operation (hatching in the figure). ) Is easily moved in a direction away from the discharge region 92, and is difficult to move on the region 92. For this reason, it is possible to suppress color mixing of ink in the ejection port 108 in the ejection region 92. Further, since the protrusion 53 a is formed on the wiper 51, the ink discharged by the first purge operation is difficult to move onto the ejection region 92. For this reason, it is possible to further suppress the color mixing of the ink in the ejection port 108 in the ejection region 92. Further, since the wiper 51 takes the first state at the first standby position, the wiper 51 wipes the ejection surface 1a in the first state during the first wiping operation. That is, in the first wiping operation, the pressure on the ejection port 108 is changed by changing the vertical inclination of the wiper 51, thereby suppressing damage to the ejection port 108 in the ejection region 92 where ink is not discharged. Is possible. For example, if the ejection surface 1a is wiped without discharging ink, the frictional force between the wiper 51 and the ejection surface 1a becomes very large. At this time, if a water repellent film or the like is formed on the ejection surface 1a, the water repellent film may be damaged. When the ejection surface 1a is wiped after the ink is discharged, the ink adheres to the ejection surface 1a, so that the frictional force is reduced by this ink and damage to the water repellent film can be suppressed. In the present embodiment, since the ink is not discharged from the ejection region 92 side in the first purge operation, the water-repellent film is easily damaged by the wiping operation after the first purge operation. However, as described above, the wiper By partially lowering the pressure on the ejection surface 1a of 51, damage to the water repellent film can be suppressed even on the side where the ink is not purged.

  In step F3, a first flushing operation is also performed. That is, the maintenance control unit 150 controls the head 1 via the head control unit 143 during the first wiping operation, and starts flushing at the ejection port 108 in the ejection region 92. That is, as shown in FIG. 10B, ink is ejected from the ejection port 108 in the order of passage of the wiper 51 and immediately after the wiper 51 has passed. For this reason, even if inks of different colors enter the ejection port 108 during wiping, they are discharged by flushing.

  When the wiper 51 reaches a predetermined position (a position indicated by a two-dot chain line in FIG. 10B) where the wiper 51 has passed through the absorber 70a, the maintenance control unit 150 controls the drive motor 59 to temporarily stop the movement. Let By this time, the first flushing operation is also finished. Then, the maintenance control unit 150 reversely rotates the drive motor 59 to return the wiper 51 to the second standby position (see FIG. 10C) between the head 1 and the absorber 70a. Thereby, the tip of the wiper 51 comes into contact with the lower surface of the absorber 70a twice, and the ink attached to the tip of the wiper 51 is effectively removed. At this time, the maintenance control unit 150 controls the guide support mechanism 58 so that the wiper 51 is in the second state.

  Next, as shown in FIG. 10C, the maintenance control unit 150 controls the head lifting mechanism 33 to move the head 1 to the printing position. Thereafter, the pump 38 is controlled to discharge ink from the ejection port 108 in the ejection area 92 onto the transport belt 43 (F4: second purge operation).

  Next, the maintenance control unit 150 controls the head lifting mechanism 33 to move the head 1 to the wiping position. Thereafter, the maintenance control unit 150 controls the drive motor 59 to move the wiper unit 55 from the second standby position in the wiping direction Y2 as shown in FIG. 10D (F5: second wiping operation). . Accordingly, the wiper 51 moves in the wiping direction Y2 while being in contact with the discharge surface 1a, and the discharge surface 1a is wiped by the wiper 51. Here, as shown in FIG. 11, since the wiper 51 is inclined with respect to the relative movement direction with respect to the ejection surface 1a, in the second wiping operation, the ink discharged in the second purge operation is ejected in the ejection region 91. It becomes easy to move away from the area, and it becomes difficult to move on the area 91. For this reason, it is possible to suppress the color mixture of the ink in the ejection port 108 in the ejection region 91. Further, both the first and second wiping operations are completed by merely reciprocating the inclined wiper 51, and color mixing in the discharge port can be suppressed in both wiping operations. Furthermore, since the wiping directions Y1 and Y2 of the first and second wiping operations are opposite to each other, the surfaces for wiping the ejection surface 1a in each wiping operation are different from each other. That is, the ejection surface 1a is wiped by the first surface 51a in the first wiping operation, and the second surface 51b in the second wiping operation. For this reason, it is possible to suppress color mixing in the wiper 51. In addition, since the protruding portion 53 b is formed on the wiper 51, the ink discharged by the second purge operation is difficult to move onto the ejection region 91. For this reason, it is possible to further suppress the color mixture of the ink in the ejection port 108 in the ejection region 91. Further, since the wiper 51 takes the second state at the second standby position, the wiper 51 wipes the ejection surface 1a in the second state in the second wiping operation. That is, in the second wiping operation, the pressure in the ejection port 108 is changed by changing the inclination of the wiper 51 in the vertical direction, thereby suppressing damage to the ejection port 108 in the ejection region 91 where ink is not discharged. Is possible. In the second purge operation, since the ink is not discharged from the discharge region 91 side, the water-repellent film is easily damaged by the wiping operation after the second purge operation. However, as described above, the discharge surface 1a of the wiper 51 By partially lowering the pressure on the water repellent film, damage to the water repellent film can be suppressed even on the side where the ink is not discharged.

  In step F5, a second flushing operation is also performed. That is, the maintenance control unit 150 controls the head 1 via the head control unit 143 during the second wiping operation, and starts flushing at the discharge port 18 of the discharge region 91. That is, as shown in FIG. 10D, ink is ejected from the ejection port 108 in the order of passage of the wiper 51 and immediately after the wiper 51 has passed. For this reason, inks of different colors that have entered during wiping are discharged by flushing.

  When the wiper 51 reaches a predetermined position (a position indicated by a two-dot chain line in FIG. 10D) where the wiper 51 has passed through the absorber 70b, the maintenance control unit 150 controls the drive motor 59 to temporarily stop the movement. Let By this time, the second flushing operation is also finished. Then, the maintenance control unit 150 rotates the drive motor 59 in the forward direction so that the wiper 51 is disposed at the first standby position (see FIG. 10E) between the head 1 and the absorber 70b. Thereby, the tip of the wiper 51 comes into contact with the lower surface of the absorber 70b twice, and the ink attached to the tip of the wiper 51 is effectively removed. At this time, the maintenance control unit 150 controls the guide support mechanism 58 so that the wiper 51 is in the first state.

  Next, as shown in FIG. 11E, the maintenance control unit 150 controls the head lifting mechanism 33 to move the head 1 to the printing position. Thereafter, the head controller 143 controls each head 1 to eject ink from all the ejection ports 108 (F6: third ejection flushing operation).

  Subsequently, the transport belt 43 is cleaned with a cleaning liquid. The maintenance control unit 150 controls the moving mechanism 37c to move the blade 37b to the contact position, and also controls the transport mechanism 40 via the transport control unit 141 to run the transport belt 43 (F7: cleaning operation). . Thereby, the discharged ink on the outer peripheral surface of the conveyance belt 43 is scraped off by the blade 37b. In this way, a series of maintenance operations are completed.

  Next, with reference to FIG. 12, a maintenance operation when a jam of the paper P occurs during printing will be described.

  First, the printer 101 receives a print command from an external device (G1). At this time, the image data storage unit 142 stores the image data included in the print command as ink ejection data from the head 1. Next, in step G <b> 2, the transport control unit 141 controls the paper feed unit 23, the guide units 10 a and 10 b, and the transport mechanism 40 to transport the paper P from the paper feed unit 23 toward the paper discharge unit 4. To start. At this time, the processing liquid control unit 145 controls the processing liquid application mechanism 2 to bring the roller 2a into contact with the transport belt 43, and also controls a processing liquid supply mechanism (not shown) so that the preprocessing liquid is supplied by a predetermined amount. Supply to roller 2a. At this time, the head control unit 143 controls each head 1 based on the image data stored in the image data storage unit 142 and starts image recording on the paper P.

  In step G3, the jam detection unit 144 determines whether or not a jam has occurred. If a jam has not occurred, the process proceeds to step G4. If a jam has occurred, the process proceeds to step G5. In step G4, the control unit 100 determines whether or not printing has ended. If not, the control unit 100 returns to step G3. When printing is completed, the processing liquid control unit 145 controls the processing liquid application mechanism 2 to separate the roller 2 a from the transport belt 43. Thus, the print flow is finished.

  In step G5, the control unit 100 controls the buzzer 28 to notify the user that a jam has occurred. When a jam is detected by the jam detection unit 144, the head control unit 143 and the conveyance control unit 141 stop the ink ejection from each head 1 and the conveyance of the paper P.

  When the user notices the buzzer sound, a jam process is performed on the printer 101. For example, when a jam occurs on the paper P between the head 1 and the conveyance belt 43, the user removes the jammed paper P. Thereafter, the user presses the push button 29. The push button 29 is provided on the top plate of the housing 101a and is pushed by the user after removing the jammed paper P. The push button 29 is pressed by the user and outputs a jam processing completion signal corresponding to the recovery from the jam to the control unit 100. As a result, a jam processing completion signal is received (step G6). When the control unit 100 receives the jam processing completion signal, the control unit 100 controls the buzzer 28 so as to stop the sound.

  Next, in step G7, a third purge operation and a wiping operation are performed. At this time, the head 1 is in the printing position. In the third purge operation, the maintenance control unit 150 controls each pump 38 to discharge ink from all the ejection ports 108 of the head 1. Then, the maintenance control unit 150 controls the head lifting mechanism 33 to move the head 1 to the wiping position. Then, the maintenance control unit 150 controls the guide support mechanism 58 so that the upper end of the wiper 51 is parallel to the ejection surface 1a. Thereafter, the maintenance control unit 150 controls the drive motor 59 to move the wiper unit 55 from the first standby position to the second standby position. Thereby, the ejection surface 1a is wiped by the wiper 51, and the ink adhering to the wiper 51 is also removed by the absorber 70a. When a jam occurs, the pretreatment liquid adhering to the paper may adhere to the ejection surface 1a. When the pretreatment liquid adheres to the ejection surface 1a, the pretreatment liquid and the ink are mixed to form a hardly soluble metal composite or the like, and the ejection port 108 may be clogged. For this reason, if the first sequence and the second sequence are performed when a jam occurs, ink is not discharged from the ejection ports 108 in the ejection region 92 in the first sequence, and the ejection ports 108 may be clogged. . In the present embodiment, when a jam occurs, the third purge operation is performed, and the wiping operation is performed after the third purge operation. That is, in the third purge operation, since the ink is discharged from the discharge areas 91 and 92, clogging of the discharge port 108 can be suppressed.

  Thereafter, the maintenance control unit 150 controls the head lifting mechanism 33 to move the head 1 to the retracted position. The maintenance control unit 150 controls the drive motor 59 to move the wiper unit 55 from the second standby position to the first standby position. At this time, since the head 1 is in the retracted position, the ejection surface 1 a is not wiped by the wiper 51. Further, when the wiper 51 is disposed at the first standby position, the maintenance control unit 150 controls the guide support mechanism 58 so that the wiper 51 is in the first state.

  Next, in step G8, the same cleaning operation as in step F7 described above is performed. Thereafter, the maintenance control unit 150 controls the head lifting mechanism 33 to move the head 1 to the printing position, and returns to Step G2. Thus, the printing that could not be performed due to the jam is resumed under the control of the transport control unit 141, the head control unit 143, and the processing liquid control unit 145.

  In this way, after the jam processing by the user is completed, the processing as described above is performed, and in step G4, when printing is completed, the flow ends.

  As described above, according to the printer 101 of the present embodiment, when the purge command other than the jam detection is received, the ejection surface 1a is wiped after the ink is purged only from the ejection area 91 or the ejection area 92. Is possible. For this reason, immediately before wiping, only single color ink is adhered to the ejection surface 1a, and ink color mixing on the ejection surface 1a is suppressed. As a result, in each wiping operation, the mixed color ink is less likely to be pushed into the ejection port 108, and color mixing can be suppressed in the ejection port 108 in each of the regions 91 and 92.

  Further, since the wiping direction Y1 in the first wiping operation and the wiping direction Y2 in the second wiping operation are opposite to each other, these wiping operations can be performed by a reciprocating operation. Further, when one purge command is received in step F1, the second sequence is performed after the first sequence, so that the time required for wiping the ejection surface 1a is shortened.

  In addition, since the wiper 51 is inclined with respect to the main and sub-scanning directions, it is difficult for the ink discharged in each purge operation to move to a region where the ink is not discharged in the first and second wiping operations. Therefore, it is possible to suppress color mixing at the discharge port. Further, since the first surface 51a wipes the ejection surface 1a in the first wiping operation and the second surface 51b in the second wiping operation, color mixture in the wiper 51 can be suppressed. Further, since the protrusions 53a and 53b are provided, in the first and second wiping operations, the ink discharged in each purge operation becomes more difficult to move to the region where the ink is not discharged. Color mixing in can be suppressed.

  Further, since the cleaning member 70 is provided, the ink adhered in each sequence can be cleaned from the wiper 51. For this reason, when the next wiping operation is performed, the ink discharged from the discharge region 91 (or the discharge region 92) becomes more difficult to enter through the discharge port 108 of the discharge region 92 (or the discharge region 91).

  Further, the ink discharged from the discharge port 108 in the discharge region 91 has a lightness smaller than that of the ink discharged from the discharge port 108 in the discharge region 92. Thereby, in the second purge operation, ink having a higher brightness than in the first purge operation is discharged. For this reason, in the second wiping operation, even if the ink discharged from the discharge port 108 of the discharge region 92 enters the discharge port 108 of the discharge region 91, the color of the ink that enters into the discharge port 108 has a high brightness, and therefore, there is an influence of color mixing. small. Even in the first wiping operation, even if ink with low brightness enters the ejection port 108 of the ejection region 92, the entered ink is discharged to the outside by the second purge operation.

  In addition, since the first flushing operation is performed during the first wiping operation and the second flushing operation is performed during the second wiping operation, even if inks of different colors enter the discharge ports 108 by each wiping operation. The ink that has permeated is discharged from the ejection port 108 by each flushing operation. For this reason, it is possible to further suppress ink color mixing in the ejection port 108.

  As a modified example, flushing may be performed from the discharge ports 108 of the discharge regions 91 and 92 that are not purged when each wiping operation is performed. The timing of the flushing at this time may be before the wiper 51 passes, or the wiper 51 may pass and the flushing may be performed at random from the discharge port 108. Also in this case, since ink is ejected from the ejection port 108, it is possible to suppress color mixing of the ink in the ejection port 108.

  In addition, since the third flushing operation is performed after the second wiping operation of the second sequence is performed, the ink meniscus of the ejection port 108 is stabilized. For this reason, the print quality does not deteriorate. Further, it is possible to further suppress the color mixture in the discharge port 108.

  As another modification, the third flushing operation may be performed after the first wiping operation until the second sequence is performed. This further stabilizes the ink meniscus at the discharge port 108. Further, it is possible to further suppress the color mixture in the discharge port 108.

  As another modification, the discharge regions 91 and 92 may not be overlapped with each other and may be close to each other through a gap. In this case, the protrusions 53a and 53b may be arranged at positions facing the gap.

  As another modification, the upper end portion of the wiper 51 may be formed with two inclined portions that are inclined downward from the center toward the outside in the sub-scanning direction. Of these inclined portions, one inclined portion is in a state that is exactly parallel to the ejection surface 1a when the wiper 51 takes the first state, and the other inclined portion is when the wiper 51 takes the second state. Then, the discharge surface 1a is in parallel. For this reason, even when the wiper 51 is in the first or second state, the contact pressure between the wiper 51 and the ejection surface 1a becomes uniform (particularly, the contact pressure on the outside does not become excessively high). For this reason, the discharge surface 1 a is less likely to be damaged by the wiper 51.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. For example, the wiper 51 may extend in parallel along the sub-scanning direction. In this case, each wiping operation may be performed by moving in the same direction.

  Further, the guide support mechanism 58 may not be provided. In this case, the pressure on the discharge surface 1a of the wiper 51 cannot be changed, but the apparatus configuration is simplified and the control is also simplified. In the guide support mechanism 58, the pressure on the discharge surface 1a of the wiper 51 is changed by changing the height of the guide 57. However, the posture changing mechanism changes the height of both ends of the discharge surface 1a in the sub-scanning direction. Thus, the posture of the head 1 may be changed, or the postures of both the head 1 and the wiper 51 may be changed.

  Further, the first and second sequences may not be performed continuously, or the first sequence may be performed after the second sequence. Further, the cleaning member 70 may not be provided. Further, the protrusions 53 a and 53 b may not be formed on the wiper 51.

  Further, the ink discharged from the discharge port 108 in the discharge region 91 may be lighter than the ink discharged from the discharge port 108 in the discharge region 92. In addition, at least one of the first to third flushing operations may not be performed.

  In the wiper unit moving mechanism 56 of the above-described embodiment, the wiper unit 55 is moved in the main scanning direction. However, the moving mechanism may move the head 1 or the wiper unit 55 and the head 1. You may move both relatively.

  The present invention is not limited to a printer, but can be applied to a facsimile, a copier, and the like. The recording medium is not limited to the paper P, and may be various recording media. Furthermore, the present invention can be applied regardless of the ink ejection method. For example, although a piezoelectric element is used in this embodiment, a resistance heating method or a capacitance method may be used.

1 head (inkjet head)
1a Discharge surface 21 Actuator unit (energy applying means)
38 Pump (Forced discharge mechanism)
51 Wiper (wiping member)
51a First surface 51b Second surface 56 Wiper unit moving mechanism (moving mechanism)
58 Guide support mechanism (posture change mechanism)
70 Cleaning member (cleaning means)
100 Control unit (control means)
101 Inkjet printer (inkjet recording device)
108 Discharge port (first and second discharge ports)
109a Discharge port array (first discharge port array)
109b Discharge port array (second discharge port array)
110 Pressure chamber

Claims (12)

A plurality of first ejection ports that eject ink arranged at equal intervals in one direction, and ink of a different color from the ink ejected from the plurality of first ejection ports, and at equal intervals in the one direction An inkjet head having an ejection surface on which a plurality of arranged second ejection ports are formed;
A wiping member extending across the first discharge port array formed by the plurality of first discharge ports and the second discharge port array formed by the plurality of second discharge ports;
A moving mechanism for relatively moving at least one of the wiping member and the inkjet head so that the wiping member moves in the one direction along the ejection surface while being in contact with the ejection surface;
A forced discharge mechanism capable of selectively discharging ink from the plurality of first discharge ports and the plurality of second discharge ports by feeding ink to the inkjet head;
A first discharge operation for forcibly discharging ink only from the plurality of first discharge ports; and an operation for wiping the discharge surface by relatively moving the wiping member, which is performed after the first discharge operation. A first sequence including a first wiping operation, a second discharge operation forcibly discharging ink only from the plurality of second discharge ports, and an operation of wiping the discharge surface by relatively moving the wiping member as a second sequence comprising a second wiping operation is selectively performed a be performed after the second discharge operation, and a control means for controlling the forced discharge mechanism and the moving mechanism ,
The relative movement direction with respect to the ejection surface of the wiping member in the first wiping operation, the inkjet recording apparatus characterized opposite der Rukoto and the relative movement direction in the second wiping operation. The wiping member has a first surface and a second surface opposite to the first surface,
In the first wiping operation, the control means is configured so that the first surface is located downstream of the second surface in the relative movement direction, and in the second wiping operation, the second surface is an ink jet recording apparatus according to claim 1, than the first face, wherein the controller controls the moving mechanism so that the downstream side of the relative movement direction. In the first wiping operation, the wiping member is configured such that a portion of the first surface facing the first discharge port array is more in a relative movement direction than a portion of the first surface facing the second discharge port array. The inkjet recording apparatus according to claim 2 , wherein the inkjet recording apparatus extends in a direction intersecting with the one direction and an orthogonal direction orthogonal to the one direction so as to be disposed upstream of the first direction. In the second wiping operation, the wiping member is configured such that a portion of the second surface facing the second ejection port array is more in a relative movement direction than a portion of the second surface facing the first ejection port array. The inkjet recording apparatus according to claim 3 , wherein the inkjet recording apparatus extends in a direction intersecting the one direction and the orthogonal direction so as to be disposed upstream of the first direction. Wherein said control means is a continuation of the first sequence, the ink jet recording apparatus according to any one of claims 1 to 4, characterized in that the second sequence. A cleaning means for cleaning the wiping member;
The control means controls at least one of the cleaning means and the moving mechanism so that the wiping member is cleaned after the first wiping operation in the first sequence. The ink jet recording apparatus according to any one of 1 to 5 . The control means controls at least one of the cleaning means and the moving mechanism so that the wiping member is cleaned after the second wiping operation in the second sequence. The inkjet recording apparatus according to 6 . The ink jet recording apparatus according to claim 5 , wherein the ink discharged from the plurality of first discharge ports has a lightness smaller than that of the ink discharged from the plurality of second discharge ports. The first discharge port array and the second discharge port array are arranged close to each other in an orthogonal direction orthogonal to the one direction,
The wiping member has a protruding portion protruding in the one direction at a position facing the region between the first discharge port array and the second discharge port array on the discharge surface in the orthogonal direction. The ink jet recording apparatus according to any one of claims 1 to 8 , wherein the ink jet recording apparatus is characterized. A plurality of first ejection ports that eject ink arranged at equal intervals in one direction, and ink of a different color from the ink ejected from the plurality of first ejection ports, and at equal intervals in the one direction An inkjet head having an ejection surface on which a plurality of arranged second ejection ports are formed;
A wiping member extending across the first discharge port array formed by the plurality of first discharge ports and the second discharge port array formed by the plurality of second discharge ports;
A moving mechanism for relatively moving at least one of the wiping member and the inkjet head so that the wiping member moves in the one direction along the ejection surface while being in contact with the ejection surface;
A forced discharge mechanism capable of selectively discharging ink from the plurality of first discharge ports and the plurality of second discharge ports by feeding ink to the inkjet head;
A first discharge operation for forcibly discharging ink only from the plurality of first discharge ports; and an operation for wiping the discharge surface by relatively moving the wiping member, which is performed after the first discharge operation. A first sequence including a first wiping operation, a second discharge operation forcibly discharging ink only from the plurality of second discharge ports, and an operation of wiping the discharge surface by relatively moving the wiping member And a control means for controlling the forced discharge mechanism and the moving mechanism so that the second sequence including the second wiping operation executed after the second discharge operation is selectively performed. ,
The inkjet head is
A plurality of pressure chambers connected to each of the plurality of first ejection ports and the plurality of second ejection ports and filled with ink;
Energy application means for applying discharge energy to the ink in the pressure chamber and discharging ink from the plurality of first discharge ports and the plurality of second discharge ports;
The control means performs the second wiping operation so that the first flushing operation of discharging ink from the plurality of second ejection ports is performed when the first wiping operation is performed. when, as a second flushing operation for discharging ink is performed from the plurality of the first discharge port, wherein the to Louis inkjet recording apparatus to control the energizing means. The control means performs a third flushing operation for ejecting ink from the plurality of first ejection ports and the plurality of second ejection ports after at least one of the first wiping operation and the second wiping operation is performed. The inkjet recording apparatus according to claim 10 , wherein the energy applying unit is controlled so as to be performed. A plurality of first ejection ports that eject ink arranged at equal intervals in one direction, and ink of a different color from the ink ejected from the plurality of first ejection ports, and at equal intervals in the one direction An inkjet head having an ejection surface on which a plurality of arranged second ejection ports are formed;
A wiping member extending across the first discharge port array formed by the plurality of first discharge ports and the second discharge port array formed by the plurality of second discharge ports;
A moving mechanism for relatively moving at least one of the wiping member and the inkjet head so that the wiping member moves in the one direction along the ejection surface while being in contact with the ejection surface;
A forced discharge mechanism capable of selectively discharging ink from the plurality of first discharge ports and the plurality of second discharge ports by feeding ink to the inkjet head;
A first discharge operation for forcibly discharging ink only from the plurality of first discharge ports; and an operation for wiping the discharge surface by relatively moving the wiping member, which is performed after the first discharge operation. A first sequence including a first wiping operation, a second discharge operation forcibly discharging ink only from the plurality of second discharge ports, and an operation of wiping the discharge surface by relatively moving the wiping member And a control means for controlling the forced discharge mechanism and the moving mechanism so that a second sequence including a second wiping operation executed after the second discharge operation is selectively performed,
A first state in which the first pressure of the wiping member with respect to the first discharge port is greater than the second pressure of the wiping member with respect to the second discharge port, and a second state in which the second pressure is greater than the first pressure. as possible states, and a posture changing mechanism for changing at least one of the posture of the inkjet head and the wiping member,
The control means to assume said first state in said first wiping operation, and to assume the second state in the second wiping operation, shall be the controls said posture changing mechanism Lee ink jet recording apparatus.