JP2010214593A - Liquid delivering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid delivering apparatus capable of avoiding stain of a conveying guide for guiding an object to be delivered, and of avoiding changing of the relative height between a liquid delivering head and a liquid tank. <P>SOLUTION: The liquid delivering apparatus includes (a) a first conveying guide 141 for guiding a sheet of paper in a paper conveying direction between a first driving roller 111 and a second driving roller 121. (b) In the first conveying guide 141, (b1) an opening part 141a into which a line type inkjet head 150 can go in and out in the vertical direction is formed on a thin plate extending from closely nearby first driving roller 111 to closely nearby second driving roller 121, and (b2) the first conveying guide 141 can move from a position just below each line type inkjet head 150 to a position above the nozzle face of each line type inkjet head 150 in a first head row 151. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid ejection apparatus that ejects liquid onto an ejection target, and in particular, can prevent the conveyance guide that guides the ejection target from becoming dirty, and the relative height between the liquid ejection head and the liquid tank can be changed. The present invention relates to a liquid ejection device that can avoid this.

  2. Description of the Related Art Conventionally, inkjet printers, microdispensers, and the like are widely known as devices that discharge liquid onto discharge objects (hereinafter referred to as liquid discharge devices). In recent years, devices that discharge electrode materials and color materials to flat panel displays have been developed by applying these technologies. A wide variety of apparatuses exist as liquid ejection apparatuses.

  For example, in an inkjet printer, the discharge target is paper, and the liquid discharged onto the discharge target is ink. Here, as the ink, water-based ink containing almost no oil component is mainly used. For this reason, if the state in which the ink is not ejected continues for a long time, the moisture of the ink spontaneously evaporates, resulting in nozzle clogging.

  Therefore, in an ink jet printer, in order to maintain and recover the performance of the ink jet head, an operation of ejecting a certain amount of ink not related to printing (hereinafter referred to as flushing) is performed immediately before printing or between printings. ), An operation of wiping off ink adhering to the tip of the nozzle (hereinafter referred to as wiping), and the like. Further, when printing is not performed, an operation of covering the nozzle surface of the inkjet head with a cap (hereinafter referred to as capping) is performed so that the ink is not dried.

  For example, the following inkjet printers have been proposed for performing maintenance (for example, flushing, wiping, capping, etc.) of the inkjet head (see, for example, Patent Document 1).

  As shown in FIG. 15A, the ink jet printer 10 raises the cap 16 with the first lifting device and raises the ink jet head 15 with the second lifting device during maintenance of the line type inkjet head 15. Flushing is performed with the nozzle surface of the line-type inkjet head 15 and the cap 16 being spaced apart. Further, as shown in FIG. 15B, the line type inkjet head 15 is lowered to a position below the conveyor belt 14 by the second lifting device. Ink suction is performed with the cap 16 in close contact with the nozzle surface of the line-type inkjet head 15. When the ink suction is completed, as shown in FIG. 15C, the cap 16 is separated from the nozzle surface of the line-type inkjet head 15, and the wiper 17 is positioned above the cap 16 until the wiper 17 is positioned. The cap 16 is lowered. As shown in FIG. 15D, wiping is performed with the upper end of the wiper 17 in contact with the nozzle surface of the line-type inkjet head 15. When the wiping is completed, as shown in FIG. 15E, the line type inkjet head 15 is lifted by the second lifting device, and the cap 16 is lifted by the first lifting device.

JP 2007-313816 A

  However, in the inkjet printer 10 described above, ink is ejected from the opening formed in the conveyance guide 14 during flushing. At this time, a part of the ejected ink becomes countless minute droplets (hereinafter referred to as ink mist). For this reason, ink mist adheres to the conveyance guide 14 and the conveyance guide 14 is soiled by the ink mist.

  In the inkjet printer 10 described above, the line inkjet head 15 moves up and down during maintenance of the line inkjet head 15. For this reason, the position of the line-type inkjet head 15 at the time of printing is easy to shift, and the relative height between the ink tank (not shown) and the line-type inkjet head 15 changes.

  Of course, these problems can occur in the same manner for liquid ejection devices other than inkjet printers. That is, even in the liquid ejecting apparatus, when maintaining the liquid ejecting head that ejects liquid onto the ejection target, the transport guide that guides the ejection target may become dirty. Further, the liquid discharge head may move up and down, and the relative height between the liquid discharge head and the liquid tank may change.

  Therefore, in view of the above problems, the present invention can avoid contamination of the conveyance guide that guides the discharge target, and can prevent the relative height of the liquid discharge head and the liquid tank from changing. It is an object of the present invention to provide a liquid ejection device that can be used.

In order to achieve the above object, a liquid ejection apparatus according to the present invention has the following characteristics.
(CL1) A liquid ejection apparatus according to the present invention is (a) a liquid ejection apparatus that ejects liquid onto an ejection object, and (b) the direction in which the ejection object is conveyed is defined as a first direction, In the case where the direction orthogonal to the first direction is the second direction and the direction orthogonal to the first direction and the second direction is the third direction on the discharge target surface of the discharge object, (C) a liquid discharge head in which a plurality of nozzles for discharging liquid are arranged; (d) a first transport roller disposed on one side in the first direction across the liquid discharge head; A second conveying roller disposed on the other side in the first direction; and (e) guiding the discharge target in the first direction between the first conveying roller and the second conveying roller. And (f) the conveyance guide (f1). The thin plate extending from the immediate vicinity of the first conveying roller to the immediate vicinity of the second conveying roller is formed with an opening through which the liquid discharge head can enter and exit in the third direction, (f2) It is movable from a position directly below the liquid discharge head to above the nozzle surface of the liquid discharge head.

  (CL2) In the liquid ejection device according to (CL1), (a) when ejecting liquid onto the ejection object, the transport guide is disposed directly below the liquid ejection head, and (b) the liquid When maintaining the ejection head, the conveyance guide moves in the third direction until the conveyance guide is retracted above the nozzle surface of the liquid ejection head.

  (CL3) In the liquid ejection device according to (CL1) or (CL2), (a) a cap that covers a nozzle surface of the liquid ejection head is disposed immediately below the liquid ejection head, and (b) the transport guide The opening formed in the cap allows the cap to enter and exit.

  (CL4) In the liquid ejection device according to (CL3), when the nozzle surface of the liquid ejection head is covered with the cap, the liquid guide is retracted above the nozzle surface of the liquid ejection head. The nozzle surface of the discharge head is covered with the cap.

  (CL5) In the liquid ejection device according to (CL3), (a) a wiper that wipes the nozzle surface of the liquid ejection head is installed on the cap, and (b) when the nozzle surface of the liquid ejection head is wiped The wiper comes into contact with the nozzle surface of the liquid ejection head in a state where the transport guide is retracted above the nozzle surface of the liquid ejection head.

  According to the present invention, when the liquid is discharged onto the discharge target, the transport guide is disposed below the nozzle surface of the liquid discharge head. Here, an opening having an opening width wider than the second direction dimension of the smallest discharge target that can be conveyed is not formed in the conveyance guide. That is, there is nothing that interferes with the conveyance of the discharge target object between the first conveyance roller and the second conveyance roller. For this reason, a discharge target object can be conveyed with a stable posture.

  When performing maintenance on the liquid discharge head, the transport guide is retracted above the nozzle surface of the liquid discharge head. That is, there is no mist generated due to the liquid ejected from the liquid ejection head, liquid that has scattered or leaked from the cap, etc. attached below the nozzle surface of the liquid ejection head. For this reason, it can avoid that a conveyance guide gets dirty.

Further, since the liquid discharge head does not move in the third direction and only the transport guide moves in the third direction, the relative height between the liquid discharge head and the liquid tank does not change.
Further, when the conveyance guide is retracted, the first conveyance roller, the second conveyance roller, and the like do not move. Instead, the conveyance guide (thin plate) moves in the third direction. For this reason, the drive part in a conveyance guide is realizable with simple structures like the mechanism which raises / lowers a thin plate. In addition, since the component to be retracted is only the transport guide (thin plate), the retracting operation becomes quick.

It is a side view which shows the liquid discharge apparatus in embodiment. It is a perspective view which shows the printing mechanism in embodiment. It is a top view which shows the printing mechanism in embodiment. It is sectional drawing which cut | disconnected the printing mechanism in embodiment along the A1-A1 line | wire, and was seen in the arrow direction. It is a schematic diagram which shows arrangement | positioning of the line-type inkjet head in embodiment. It is a perspective view which shows the state in which the conveyance guide part in embodiment is closed. It is a perspective view which shows the state in which the conveyance guide part in embodiment is open. It is a side view which shows the drive part of the conveyance guide part in embodiment. It is a schematic diagram which shows the operation | movement at the time of the printing of the printing mechanism in embodiment. It is a schematic diagram which shows the operation | movement at the time of the flushing of the printing mechanism in embodiment. It is a schematic diagram which shows the operation | movement at the time of wiping of the printing mechanism in embodiment. It is a schematic diagram which shows the operation | movement at the time of capping of the printing mechanism in embodiment. It is a schematic diagram which shows the operation | movement at the time of the flushing of the printing mechanism in the modification of embodiment. It is a schematic diagram which shows the operation | movement at the time of capping of the printing mechanism in the modification of embodiment. (A)-(E) is a front view which shows the inside at the time of the maintenance in the conventional inkjet printer.

(Embodiment)
Embodiments according to the present invention will be described below.
<Overview>
The liquid ejection apparatus according to the present embodiment has the features shown in the following (1) to (5).

  (1) The liquid ejection device is (a) a liquid ejection device that ejects liquid onto an ejection object, and (b) a direction in which the ejection object is conveyed is defined as a first direction, and the ejection target is ejected. In the case where the direction orthogonal to the first direction on the surface is the second direction and the direction orthogonal to the first direction and the second direction is the third direction, (c) a plurality of liquid ejecting liquids A liquid discharge head in which nozzles are arranged; (d) a first transport roller disposed on one side in the first direction across the liquid discharge head; and a first transport roller disposed on the other side in the first direction. 2 transport rollers, and (e) a transport guide for guiding an ejection target object in the first direction between the first transport roller and the second transport roller, and (f) the transport guide is (f1) Can be transported to a thin plate extending from the immediate vicinity of the first transport roller to the immediate vicinity of the second transport roller The opening dimension in the second direction is narrower than the dimension in the second direction in the smallest discharge target, and an opening through which the liquid ejection head can enter and exit in the third direction is formed (f2 ) It can move from a position directly below the liquid discharge head to above the nozzle surface of the liquid discharge head.

  (2) In the liquid ejection device, (a) when ejecting liquid onto the ejection target, a transport guide is disposed directly below the liquid ejection head, and (b) when maintaining the liquid ejection head, the liquid ejection head The conveyance guide moves in the third direction until the conveyance guide retracts above the nozzle surface.

  (3) In the liquid ejection device, (a) a cap that covers the nozzle surface of the liquid ejection head is disposed directly below the liquid ejection head, and (b) an opening formed in the transport guide is capable of entering and exiting the cap. It is.

  (4) In the liquid ejection device, when the nozzle surface of the liquid ejection head is covered with the cap, the nozzle surface of the liquid ejection head is covered with the cap in a state where the transport guide is retracted above the nozzle surface of the liquid ejection head.

  (5) In the liquid ejection device, (a) a wiper is installed on the cap to wipe the nozzle surface of the liquid ejection head, and (b) when the nozzle surface of the liquid ejection head is wiped, the transport guide is the nozzle surface of the liquid ejection head. The wiper comes into contact with the nozzle surface of the liquid ejection head in the state of being retracted upward.

  Based on the above points, the liquid ejection apparatus according to the present embodiment will be described using an inkjet printing apparatus as an example. Note that in an inkjet printing apparatus, a discharge target is paper, and a liquid discharged to the discharge target is ink.

<Configuration>
Here, as an example, as shown in FIG. 1, the liquid ejecting apparatus 100 is a printing apparatus that ejects aqueous ink onto a sheet by an inkjet method. One or more sheets 50 stacked on the sheet feeding table 101 are supplied to the printing mechanism 103 by the sheet feeding mechanism 102 one by one. A raster image is printed on the paper 50 supplied to the printing mechanism 103. The paper 50 on which the raster image is printed is discharged to the paper receiving tray 105 via the paper discharge mechanism 104.

Hereinafter, the surface of the paper 50 is referred to as a printing surface. When the printing mechanism 103 is viewed from the paper discharge side, the left side is the front and the right side is the back.
<Printing mechanism 103>
As shown in FIG. 2 to FIG. 4, the printing mechanism 103 includes a first conveying roller unit 110, a second conveying roller unit 120, and a third conveying roller unit 130 in order from the paper feeding side. Installed on the frame 106. A plurality of line-type inkjet heads 150 are installed above the conveyance guide unit 140. A single raster image is printed by a plurality of line-type inkjet heads 150 on a sheet conveyed from the sheet feeding side to the sheet discharging side.

<First conveying roller unit 110>
The first transport roller unit 110 includes a first drive roller 111 and a first driven roller 112 that forms a pair with the first drive roller 111. The first drive roller 111 is disposed on the back side of the paper being transported and actively rotates in the direction of feeding the paper in the paper transport direction. The first driven roller 112 is disposed on the front side of the paper being transported, and passively rotates in the direction of feeding the paper in the paper transport direction following the rotation of the first drive roller 111. .

<Second conveying roller unit 120>
The second conveying roller unit 120 includes a second driving roller 121 and a second driven roller 122 that forms a pair with the second driving roller 121. The second drive roller 121 is disposed on the back side of the sheet being conveyed and actively rotates in the direction of feeding the sheet in the sheet conveyance direction. The second driven roller 122 is disposed on the front surface side of the paper being transported, and passively rotates in the direction of feeding the paper in the paper transport direction following the rotation of the second drive roller 121. .

<Third conveying roller unit 130>
The third transport roller unit 130 includes a third drive roller 131 and a third driven roller 132 that forms a pair with the third drive roller 131. The third drive roller 131 is disposed on the back side of the sheet being conveyed, and actively rotates in the direction of feeding the sheet in the sheet conveyance direction. The third driven roller 132 is disposed on the front side of the sheet being conveyed, and passively rotates in the direction of feeding the sheet in the sheet conveyance direction following the rotation of the third drive roller 131. .

<Conveyance guide unit 140>
The conveyance guide unit 140 includes a first conveyance guide 141 and a second conveyance guide 142 that forms a pair with the first conveyance guide 141. The first transport guide 141 guides the paper supplied from the upstream to the second transport roller unit 120. The second conveyance guide 142 guides the sheet sent out from the second conveyance roller unit 120 to the downstream side.

<Line-type inkjet head 150>
As shown in FIGS. 2 to 4, three printing mechanisms 103 are provided in a portion between the first conveyance roller unit 110 and the second conveyance roller unit 120 (hereinafter referred to as a pre-stage portion). The line-type inkjet head 150 is installed. Three line-type inkjet heads 150 are installed in a portion between the second conveyance roller unit 120 and the third conveyance roller unit 130 (hereinafter referred to as a subsequent portion). The maximum printable range is shared and printed by a total of six line-type inkjet heads 150.

  Here, the maximum printable range is the maximum range that can be printed by the printing mechanism 103. For each of the front part and the rear part, the length (size in the paper conveyance direction) is longer than the length (size in the paper conveyance direction) of the smallest size paper (hereinafter referred to as the smallest paper that can be conveyed). short. The width (size in the paper width direction) is wider than the width (size in the paper width direction) of the maximum size paper that can be carried (hereinafter referred to as the maximum carryable paper).

  Each line type inkjet head 150 ejects a plurality of colors by one. A plurality of nozzles (not shown) of the same color are arranged above the conveyance guide unit 140 so that a plurality of nozzles (not shown) of each color are arranged in the paper conveyance direction. During printing, it is used in a state of being fixed above the conveyance guide section 140. Here, as an example, it is assumed that the maximum printable range is divided in the paper width direction in units of partial print areas as viewed from the paper discharge side.

  In this case, as shown in FIG. 5, three line-type ink jet heads 150 (hereinafter referred to as first head rows 151) installed in the preceding stage are individually arranged above the odd-numbered areas. Responsible for printing odd areas. Three line-type inkjet heads 150 (hereinafter referred to as second head rows 152) installed in the rear stage are individually arranged above the even area and are responsible for printing the even area.

  Here, the partial printing region is a range that can be printed by one line-type inkjet head 150 on the printing surface. The odd area is an odd-numbered partial print area (partial print area 1, partial print area 3, partial print area 5, etc. in the figure) of the maximum printable range counted from the front. The even-numbered area is an even-numbered partial print area (partial print area 2, partial print area 4, partial print area 6, etc. in the figure) of the maximum printable range counted from the front.

<Cap 160>
In the printing mechanism 103, a rectangular opening (hereinafter referred to as a pre-stage opening 106a) is formed in a portion of the frame 106 between the first conveyance roller unit 110 and the second conveyance roller unit 120. Has been. A rectangular opening (hereinafter referred to as a rear-stage opening 106b) is formed in a portion of the frame 106 between the second conveyance roller unit 120 and the third conveyance roller unit 130. Three caps 160 are installed in the front opening 106a. Three caps 160 are installed in the rear opening 106b. At this time, three caps 160 (hereinafter referred to as first cap rows 161) installed in the front opening 106 a are individually provided directly below each line-type inkjet head 150 in the first head row 151. Be placed. Three caps 160 (hereinafter referred to as a second cap row 162) installed in the rear opening 106b are individually arranged directly below each line-type inkjet head 150 in the second head row 152. .

  Here, the front opening 106a has a length (a dimension in the paper conveyance direction) longer than a depth of the line-type inkjet head 150 (a dimension in the paper conveyance direction). The width (size in the paper width direction) is wider than the entire width (size in the paper width direction) of the first head row 151. The rear opening 106b has a length (size in the paper conveyance direction) longer than the depth (size in the paper conveyance direction) of the line-type inkjet head 150. The width (size in the paper width direction) is wider than the entire width (size in the paper width direction) of the second head row 152.

  Each cap 160 fulfills a moisturizing function. At the time of printing, it is arranged below the conveyance guide unit 140 so as to face each line-type inkjet head 150. It is disposed below each line-type inkjet head 150. At the time of flushing and wiping, it rises to the vicinity of the nozzle surface of each line-type inkjet head 150. During capping, the nozzle surface of each line-type inkjet head 150 is covered.

<Specific example of conveyance guide unit 140>
Next, the conveyance guide unit 140 will be described in detail.
As shown in FIGS. 6 and 7, the transport guide unit 140 has a first transport guide 141 installed in the front part and a second transport guide 142 installed in the rear part.

6 and 7 are shown in a state where a part of the printing mechanism 103 is removed in order to make the structure of the conveyance guide unit 140 easy to see.
<First transport guide 141>
Specifically, the first conveyance guide 141 is provided with wall portions 141b that stand individually in the short direction and extend straight downward on both sides of one rectangular thin plate in which the opening portion 141a is formed. It is. The width of the rectangular thin plate (longitudinal dimension) is wider than the width of the largest sheet that can be conveyed (dimension in the paper width direction). The length of the rectangular thin plate (dimension in the short direction) is substantially the same as the distance from the closest downstream side of the first drive roller 111 to the immediate upstream side of the second drive roller 121. Three openings 141a extending in the short direction are formed in the longitudinal direction.

  Here, the opening shape of each opening 141a is rectangular. The width (dimension in the longitudinal direction) is wider than the width of the line-type inkjet head 150 (dimension in the paper width direction). The length (dimension in the short direction) is longer than the depth (dimension in the paper conveyance direction) of the line-type inkjet head 150.

  Further, the length (vertical dimension) of each wall 141b is longer than the distance between the surface of the first conveyance guide 141 and the lower surface of the line-type inkjet head 150 during printing. The width (longitudinal dimension) is substantially the same as the width (longitudinal dimension) of the rectangular thin plate. Further, at least one of the wall portions 141b is subjected to gear cutting to form teeth along the vertical direction. Here, as an example, teeth are formed on the edge portion in front of the wall portion 141b arranged on the first drive roller 111 side.

  Further, the first conveyance guide 141 is arranged in the front stage portion with the short side direction aligned with the sheet conveyance direction and the long side direction aligned with the sheet width direction. It is installed on the frame 106 of the printing mechanism 103 with the surface maintained horizontal. At this time, each wall part 141b is arrange | positioned in the back surface side of the 1st conveyance guide 141 in the state which can raise / lower vertically. That is, when viewed from the front of the printing mechanism 103, the first conveyance guide 141 that looks like an inverted U-shape is installed on the frame 106 of the printing mechanism 103 in a state where it can be raised and lowered in the vertical direction.

<Second transport guide 142>
On the other hand, the second conveyance guide 142 is provided with wall portions 142b that stand individually in the short-side direction and extend straight downward on both sides of one rectangular thin plate in which the opening 142a is formed. The width of the rectangular thin plate (longitudinal dimension) is wider than the width of the largest sheet that can be conveyed (dimension in the paper width direction). The length of the rectangular thin plate (dimension in the short direction) is substantially the same as the distance from the closest upstream side of the third drive roller 131 to the closest downstream side of the second drive roller 121. Three openings 142a extending in the short direction are formed in the longitudinal direction.

  Here, the opening shape of each opening 142a is rectangular. The width (dimension in the longitudinal direction) is wider than the width of the line-type inkjet head 150 (dimension in the paper width direction). The length (dimension in the short direction) is longer than the depth (dimension in the paper conveyance direction) of the line-type inkjet head 150.

  Further, the length (vertical dimension) of each wall 142b is longer than the distance between the surface of the second conveyance guide 142 and the lower surface of the line-type inkjet head 150 during printing. The width (longitudinal dimension) is substantially the same as the width (longitudinal dimension) of the rectangular thin plate. Further, at least one of the wall portions 142b is subjected to gear cutting to form teeth along the vertical direction. Here, as an example, teeth are formed on the edge portion in front of the wall portion 142b arranged on the third drive roller 131 side.

  Further, the second conveyance guide 142 is arranged in the rear stage portion with the short side direction aligned with the sheet conveyance direction and the long side direction aligned with the sheet width direction. It is installed on the frame 106 of the printing mechanism 103 with the surface maintained horizontal. At this time, each wall part 142b is arrange | positioned in the back surface side of the 2nd conveyance guide 142 in the state which can raise / lower vertically. That is, when viewed from the front side of the printing mechanism 103, the second conveyance guide 142 that looks like an inverted U-shape is installed on the frame 106 of the printing mechanism 103 in a state where it can be raised and lowered in the vertical direction.

<Drive unit of conveyance guide unit 140>
Next, the drive part of the conveyance guide part 140 is demonstrated.
As shown in FIG. 8, the transport guide unit 140 is provided with a first drive unit 143 below the first transport guide 141 and in front of the printing mechanism 103. In addition, a second drive unit 144 is installed below the second conveyance guide 142 and before the printing mechanism 103.

<First driving unit 143>
The first drive unit 143 includes a motor 143a controlled by a control unit (not shown) provided in the printing mechanism 103, and a small-diameter circular gear 143b attached to the shaft tip of the motor 143a.

Here, as for the small-diameter circular gear 143b, teeth that mesh with teeth formed on the wall 141b of the first conveyance guide 141 are formed on the outer periphery.
The first driving unit 143 has a small-diameter circular gear 143b disposed in front of the printing mechanism 103 below the first conveyance guide 141 with the axial direction of the shaft aligned with the paper width direction. The motor 143a is installed on the frame 106 of the printing mechanism 103 in a state where the teeth formed on the wall 141b and the small-diameter circular gear 143b mesh with each other. The first conveyance guide 141 moves in the vertical direction by driving the motor 143a.

<Second driving unit 144>
The second drive unit 144 includes a motor 144a controlled by a control unit (not shown) provided in the printing mechanism 103, and a small-diameter circular gear 144b attached to the shaft tip of the motor 144a.

Here, as for the small-diameter circular gear 144b, teeth that mesh with teeth formed on the wall 142b of the second conveyance guide 142 are formed on the outer periphery.
In the second drive unit 144, the small-diameter circular gear 144 b is arranged in front of the printing mechanism 103 below the second conveyance guide 142 so that the axial direction of the shaft is aligned with the paper width direction. The motor 144a is installed on the frame 106 of the printing mechanism 103 with the teeth formed on the wall 142b and the small-diameter circular gear 144b meshing with each other. The second conveyance guide 142 moves in the vertical direction by driving the motor 144a.

<Operation>
Next, the operation of the printing mechanism 103 will be described. Here, operations during printing, operations during flushing, operations during wiping, and operations during capping will be described.

  When the first conveyance guide 141 is retracted outside the area below each nozzle surface in the first head row 151, the nozzle surface of the line-type inkjet head 150 protrudes downward from the back surface of the first conveyance guide 141. Until this is done, the first conveyance guide 141 is raised. Furthermore, when the first conveyance guide 141 returns to the area below each nozzle surface in the first head row 151, a predetermined distance (for example, about 0.8 mm) upward from the surface of the first conveyance guide 141. ) Until the upper portion of the first drive roller 111 protrudes.

  Similarly, when the second conveyance guide 142 is retracted outside the area below each nozzle surface in the second head row 152, the nozzle surface of the line-type inkjet head 150 is downward from the back surface of the second conveyance guide 142. The second conveyance guide 142 is raised until it protrudes. Furthermore, when the second conveyance guide 142 returns to the area below each nozzle surface in the second head row 152, the distance from the surface of the second conveyance guide 142 is a predetermined distance (for example, about 0.8 mm). ) Until the upper portion of the third drive roller 131 protrudes.

9 to 12 are displayed with the frame 106 removed in order to make the structure of the printing mechanism 103 easier to see.
<When printing>
As shown in FIG. 9, the printing mechanism 103 is arranged below the first head row 151 so as to extend from the immediate downstream side of the first drive roller 111 to the immediate upstream side of the second drive roller 121 during printing. A first transport guide 141 is disposed. The sheet fed from the first drive roller 111 is guided to the second drive roller 121 by the first transport guide 141.

  Similarly, the second conveyance guide 142 is disposed below the second head row 152 so as to extend from the immediate upstream side of the third drive roller 131 to the immediate downstream side of the second drive roller 121. The sheet fed from the second drive roller 121 is guided to the third drive roller 131 by the second transport guide 142.

  At this time, the upper portion of the first drive roller 111 protrudes upward from the surface of the first conveyance guide 141 by a predetermined distance (for example, about 0.8 mm). The upper portion of the third drive roller 131 protrudes upward from the surface of the second conveyance guide 142 by a predetermined distance (for example, about 0.8 mm).

<During flushing>
As shown in FIG. 10, during the flushing, the printing mechanism 103 is driven by the motor 143 a until the nozzle surface of the line-type inkjet head 150 projects downward from the back surface of the first conveyance guide 141. The guide 141 rises. A fixed amount of ink is ejected from the first head row 151 toward the first cap row 161.

  Similarly, the second conveyance guide 142 is raised until the motor 144 a is driven and the nozzle surface of the line-type inkjet head 150 protrudes downward from the back surface of the second conveyance guide 142. A certain amount of ink is ejected from the second head row 152 toward the second cap row 162.

<When wiping>
As shown in FIG. 11, during the wiping, the printing mechanism 103 is driven by the motor 143 a until the nozzle surface of the line-type inkjet head 150 protrudes downward from the back surface of the first conveyance guide 141. The guide 141 rises. The first cap row 161 is raised until the wiper 160a provided in each cap 160 in the first cap row 161 contacts each nozzle surface in the first head row 151. Each wiper 160a in the first cap row 161 moves in the paper width direction in a state of being in contact with each nozzle surface in the first head row 151. Ink adhering to each nozzle surface in the first head row 151 is wiped off by each wiper 160 a in the first cap row 161.

  Similarly, the second conveyance guide 142 is raised until the motor 144 a is driven and the nozzle surface of the line-type inkjet head 150 protrudes downward from the back surface of the second conveyance guide 142. The second cap row 162 is raised until the wiper 160 a provided in each cap 160 in the second cap row 162 contacts each nozzle surface in the second head row 152. Each wiper 160a in the second cap row 162 moves in the paper width direction while being in contact with each nozzle surface in the second head row 152. Ink adhering to each nozzle surface in the second head row 152 is wiped off by each wiper 160 a in the second cap row 162.

<When capping>
As shown in FIG. 12, the printing mechanism 103 performs the first conveyance until the nozzle surface of the line-type inkjet head 150 protrudes downward from the back surface of the first conveyance guide 141 when the motor 143 a is driven during capping. The guide 141 rises. The first cap row 161 is raised, and each nozzle surface in the first head row 151 is covered with each cap 160 in the first cap row 161.

  Similarly, the second conveyance guide 142 is raised until the motor 144 a is driven and the nozzle surface of the line-type inkjet head 150 protrudes downward from the back surface of the second conveyance guide 142. The second cap row 162 rises and each nozzle surface in the second head row 152 is covered with each cap 160 in the second cap row 162.

<Summary>
As described above, according to the present embodiment, the first transport guide 141 is disposed below each nozzle surface in the first head row 151 during printing. Here, an opening having an opening width wider than the width of the smallest transportable sheet (the dimension in the sheet width direction) is not formed in the first transport guide 141. That is, there is no obstacle between the first conveyance roller unit 110 and the second conveyance roller unit 120 that interferes with the conveyance of the sheet. For this reason, the leading edge of the sheet does not go from the first conveying roller section 110 to the second conveying roller section 120, and the sheet is guided in a stable posture. As a result, the posture of the paper is stabilized, so that jamming is less likely to occur.

  Further, during maintenance of the line-type inkjet head 150 (for example, during flushing, wiping, capping, etc.), the first transport guide 141 is retracted above each nozzle surface in the first head row 151. In other words, there is no ink mist or ink scattered or leaked from the cap 160 on the lower surface of each nozzle in the first head row 151. For this reason, it can avoid that the 1st conveyance guide 141 becomes dirty.

  Further, each line type ink jet head 150 does not move in the vertical direction, and only the first transport guide 141 moves in the vertical direction, so that the relative height between the ink jet head 150 and the ink tank (not shown) does not change.

  Further, when the first conveyance guide 141 is retracted, the first conveyance roller unit 110, the second conveyance roller unit 120, and the like do not move. Instead, the first conveyance guide 141 (thin plate) moves in the vertical direction. For this reason, the drive part in the 1st conveyance guide 141 is realizable with simple structures like the mechanism which raises / lowers a thin plate. In addition, since the component to be retracted is only the first transport guide 141 (thin plate), the retracting operation becomes quick.

  Further, when each nozzle surface in the first head row 151 is covered with each cap 160 in the first cap row 161 as in capping, an ink film is formed between each nozzle surface and each cap 160. May be formed. When the caps 160 are separated from the nozzle surfaces with the ink film formed, the ink film is broken and scattered. However, even in such a case, the front wheel side of the first conveyance guide 141 is prevented from becoming dirty by retracting the first conveyance guide 141 above each nozzle surface in the first head row 151. be able to. Furthermore, since each nozzle surface is sandwiched between the wall portions 141b, even if the ink film is broken and scattered, it is only necessary to stain the back surface side of the first conveyance guide 141. It is also possible to avoid contamination of the second transport roller unit 120 and the like.

The same applies to the second transport guide 142.
<Modification>
(1) As shown in FIG. 13, the printing mechanism 103 is configured so that each cap 160 positioned immediately below each line-type inkjet head 150 is close to the nozzle surface of each line-type inkjet head 150 during flushing. Each cap 160 may rise.

  (2) As shown in FIG. 14, the printing mechanism 103 is configured so that the first head extends from the position closest to the downstream side of the first drive roller 111 to the position close to the upstream side of the second drive roller 121 during capping. A first transport guide 141 is disposed below the row 151. The first cap row 161 may rise so that each nozzle surface in the first head row 151 is covered with each cap 160 in the first cap row 161.

At this time, the upper portion of the first drive roller 111 protrudes upward from the surface of the first conveyance guide 141 by a predetermined distance (for example, about 0.8 mm).
Thus, even if each cap 160 is moved up and down without retracting the first conveyance guide 141, it is possible to avoid interference with the first conveyance guide 141, and the nozzle surface of each line-type inkjet head 150. Can be covered with each cap 160.

Further, even when ink mist is not generated as in capping, the first conveyance guide 141 can be avoided from being retracted, and the number of retracts can be reduced.
The same applies to the second conveyance guide 142.

  (3) Each line-type inkjet head 150 realizes a plurality of colors by combining a plurality of line-type inkjet heads 150 that discharge a single color with a single line-type inkjet head 150 and discharge different colors. It may be. Further, two or more stages may be arranged in the sheet conveyance direction, or three or more stages may be arranged in the sheet width direction. Moreover, it may be arranged in a staggered arrangement.

  (4) Note that one of the first conveyance guide 141 and the second conveyance guide 142 may be formed of a low friction member. Alternatively, the surface may be coated with a low friction agent. Further, a plurality of ribs along the transport direction may be formed on the surface.

(5) In addition to the common water-based ink, examples of the ink include various liquid compositions such as oil-based ink, gel ink, and hot melt ink.
(6) The liquid ejection device 100 may eject other liquids in addition to ink as long as it is a material that can be ejected. For example, as the other liquid, the substance may be in a liquid phase, (a) a liquid having high or low viscosity, (b) liquid crystal, (c) sol, (d) gel water, (e) an inorganic solvent, (F) Organic solvents, (g) solutions, (h) liquid resins, (i) molten metals, and the like. Further, (j) a functional material made of a solid such as a pigment or metal particles is dissolved in a solvent, (k) a functional material made of a solid such as a pigment or metal particles is dispersed in a solvent, (l And a mixture of two or more kinds of functional materials made of solid materials such as pigments and metal particles in a solvent.

(7) It should be noted that the liquid may be discharged from the liquid discharge device 100 so as to draw a tail in a drop shape, a granular shape, a tear shape, or a thread shape.
(8) The liquid ejection device 100 may be, for example, (a) a textile printing device, (b) a micro-dispenser, in addition to the ink jet printing device. In addition, (c) as an apparatus for discharging a liquid containing a material in which a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an electroluminescence display, a surface emitting display, a color filter, or the like is dispersed or dissolved. Also good. Moreover, (d) It is good also as an apparatus which discharges the bioorganic matter used for manufacture of a biochip. Moreover, (e) It is good also as an apparatus which discharges the liquid used as the sample used as a precision pipette. Moreover, (f) It is good also as an apparatus which discharges lubricating oil pinpoint to precision machines, such as a timepiece and a camera. (G) In order to form a micro hemispherical optical lens used for an optical communication element or the like, a device that discharges a transparent resin liquid such as an ultraviolet curable resin onto a substrate may be used. (H) In order to etch a substrate or the like, an apparatus for discharging an etchant such as acid or alkali may be used.

  (9) In addition to the paper, the discharge target includes a substrate, a color filter, a fiber material, a three-dimensional object, and the like.

  The present invention can avoid contamination of a transport guide that guides a discharge target, particularly as a liquid discharge device that discharges liquid onto a discharge target, and the relative height between the liquid discharge head and the liquid tank is reduced. It can be used as a liquid ejecting apparatus that can avoid the change.

DESCRIPTION OF SYMBOLS 10 Liquid discharge apparatus 14 Conveyance guide 15 Line type inkjet head 16 Cap 17 Wiper 50 Paper 100 Liquid discharge apparatus 101 Paper feed stand 102 Paper feed mechanism 103 Printing mechanism 104 Paper discharge mechanism 105 Paper receiving stand 106 Frame 106a Front opening 106b Rear opening Unit 110 first transport roller unit 111 first drive roller 112 first driven roller 120 second transport roller unit 121 second drive roller 122 second driven roller 130 third transport roller unit 131 third transport roller unit 131 Driving roller 132 Third driven roller 140 Conveying guide portion 141 First conveying guide 141a Opening portion 141b Wall portion 142 Second conveying guide 142a Opening portion 142b Wall portion 143 First driving portion 143a Motor 143b Small-diameter circular gear 144 Second drive unit 144a Motor 144b Small Apertured circular gear 150 Line-type inkjet head 151 First head row 152 Second head row 160 Cap 160a Wiper 161 First cap row 162 Second cap row

Claims (5)

A liquid ejection device that ejects liquid onto an ejection object,
The first direction is the first direction, and the second direction is the direction orthogonal to the first direction on the surface to be discharged of the discharge target object. In the case where the direction orthogonal to the direction is the third direction,
A liquid discharge head in which a plurality of nozzles for discharging liquid are arranged;
A first transport roller disposed on one side in the first direction across the liquid ejection head; a second transport roller disposed on the other side in the first direction;
A conveyance guide for guiding the discharge object in the first direction between the first conveyance roller and the second conveyance roller;
The conveyance guide is formed in a thin plate extending from a position near the first conveyance roller to a position near the second conveyance roller, and an opening through which the liquid discharge head can enter and exit in the third direction is formed. The liquid ejecting apparatus is capable of moving from a position directly below the liquid ejecting head to above the nozzle surface of the liquid ejecting head. When discharging the liquid onto the discharge target, the transport guide is disposed directly below the liquid discharge head,
2. When the maintenance of the liquid discharge head is performed, the transport guide moves in the third direction until the transport guide is retracted above the nozzle surface of the liquid discharge head. Liquid ejection device. A cap that covers the nozzle surface of the liquid discharge head is disposed directly below the liquid discharge head,
The liquid ejecting apparatus according to claim 1, wherein the opening formed in the transport guide allows the cap to enter and exit. When the nozzle surface of the liquid discharge head is covered with the cap, the nozzle surface of the liquid discharge head is covered with the cap in a state where the transport guide is retracted above the nozzle surface of the liquid discharge head. The liquid ejection device according to claim 3. The cap is provided with a wiper that wipes off the nozzle surface of the liquid discharge head,
The wiper contacts the nozzle surface of the liquid ejection head when the nozzle surface of the liquid ejection head is wiped off, with the transport guide retracted above the nozzle surface of the liquid ejection head. 4. The liquid ejection device according to 3.

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