JP2016150555A - Liquid discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid discharge device that can suppress the device from increasing in size and improve maintainability of the device.SOLUTION: The liquid discharge device comprises: a plurality of liquid discharge heads for discharging liquid arranged with proper gaps; a housing member that covers the plurality of liquid discharge heads while exposing at least the gaps and nozzle surfaces of the liquid discharge heads; and gas supplying means that supplies gas to a space communicated with the gaps in the housing member so as to blow out the gas from the space through the gaps toward outside of the housing member. The liquid discharge device comprises a wiper for wiping the nozzle surfaces.SELECTED DRAWING: Figure 14

Description

  The present invention relates to a liquid discharge apparatus including a liquid discharge head that discharges liquid, represented by an ink jet printer.

  A line printer as an example of a liquid ejection apparatus is provided with nozzles over a length corresponding to the entire width of a recording sheet as an example of a medium to be ejected. Some line printers constitute a line head by connecting a plurality of heads (head units, head modules, etc.) provided with the nozzles.

  In this line head, when connecting the plurality of heads, a gap as an adjustment margin for adjusting the position of each head is provided between the heads. In the line head configured as described above, when the nozzle surface is wiped by the wiper member, a part of the ink removed from the nozzle surface by the wiper member may enter the gap. Further, mist generated when ink is ejected may enter the gap. If the ink that has entered the gap falls onto the recording paper, the recording surface may be soiled and the recording quality may be impaired.

  Therefore, a line printer that can remove ink that has entered the gap is known (Patent Document 1).

JP2013-193431A

  In this line printer, the line head is configured by connecting a plurality of heads in the longitudinal direction of the line head. A gap is formed between the line heads adjacent to each other. A tube support member is attached to the side of the gap opposite to the liquid discharge surface of the head so as to fill the gap. A tube is inserted into the tube support member. One end of the tube is located in the gap, and the other end is connected to a gas supply means for supplying gas to the gap between the heads.

  In a line printer having this line head, when ink enters the gap when the nozzle surface is cleaned with a wiper member, the gas is supplied from the gas supply means to the gap through the tube. The ink is discharged from the gap.

  By the way, since the gap between the line heads is an adjustment margin in the head assembly, the gap is not uniform. Thereby, the tube support member needs to prepare a plurality of the tube support members having different dimensions of the portion filling the gap in order to cope with the non-uniform gap. As a result, the manufacturing cost of the printer increases. In addition, since gas is supplied from each tube to each gap, a plurality of tubes extend from the gas supply means toward the line head, and the path is provided in the apparatus and in the line head. There is a possibility that the apparatus becomes large.

  Further, when the head is replaced due to a failure or a lifetime in the line head, the tube and the tube support member must be detached, and the workability of the replacement work is inferior.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a liquid ejection apparatus that can suppress the enlargement of the apparatus and improve the maintainability of the apparatus.

  In order to achieve the above object, a liquid ejection apparatus according to the first aspect of the present invention includes a plurality of liquid ejection heads that eject liquid, with an appropriate gap, and at least the gap and nozzles of the liquid ejection head. A housing member that covers the plurality of liquid discharge heads in a state where the surface is exposed; and a gas is supplied to the space that communicates with the gap in the housing member, so that the housing member passes through the gap from the space. And a gas supply means for blowing out gas toward the outside.

  According to this aspect, since the gas is blown out from the space toward the outside of the housing member via the gap, the liquid can be prevented from entering the gap, or the liquid that has entered the gap can be prevented. It is possible to discharge the liquid, and it is possible to eliminate problems caused by liquid entering the gap. And the structure of such an apparatus can be simplified and the enlargement of an apparatus can be suppressed. Moreover, since the configuration of the apparatus can be simplified, the maintainability of the apparatus can be improved.

  In addition, the space in this aspect is not limited to the case where it is formed in the housing member as a dedicated space for supplying gas from the gas supply means to the gap in the housing member. It means that a space formed in the housing member by containing the liquid discharge head or the like in the member is also included. Further, the space does not mean a space having a certain size or more in the housing member, and the housing member and the liquid discharge head in a state where the liquid discharge head is accommodated in the housing member. A narrow space formed between the gas supply means, for example, a flow path for supplying the gas from the gas supply means to the gap.

  The liquid ejection apparatus according to a second aspect of the present invention is characterized in that, in the first aspect, a wiper for wiping the nozzle surface is provided.

  The liquid ejection apparatus according to a third aspect of the present invention is characterized in that, in the first or second aspect, the air pressure in the space is higher than the air pressure outside the housing member.

  According to this aspect, since the air pressure in the space is higher than the air pressure outside the housing member, the gas surely flows from the inside of the housing member to the outside of the housing member in the gap. Therefore, the liquid can be reliably prevented from entering the gap, and the liquid that has entered the gap can be reliably discharged.

  The liquid ejection apparatus according to a fourth aspect of the present invention is characterized in that, in any one of the first to third aspects, the gap increases from the nozzle surface side toward the space side.

  According to this aspect, even if the liquid enters the nozzle surface side in the gap, the gap becomes larger from the nozzle surface side toward the space side, so that the capillary phenomenon hardly occurs, and the liquid does not It can suppress entering to the said space side of a clearance gap.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the gas supply means intermittently supplies the gas to the space.

  According to this aspect, since the gas supply means intermittently supplies the gas to the space, the gas is intermittently blown out from the space toward the outside of the housing member through the gap. . As a result, for example, even if a highly viscous liquid enters the gap, the gas is intermittently blown to the liquid to give vibration, so that the discharge of the liquid from the gap can be improved.

  The liquid ejection device according to a sixth aspect of the present invention is characterized in that, in any one of the first to fourth aspects, the gas supply means periodically increases or decreases the supply amount of the gas to the space. To do.

  According to this aspect, since the gas supply means periodically increases or decreases the supply amount of the gas to the space, the flow rate of the gas blown out from the space through the gap toward the outside of the housing member is Increase or decrease periodically. As a result, for example, even if a highly viscous liquid enters the gap, the liquid is vibrated by periodically increasing or decreasing the flow rate of the gas sprayed on the liquid, so that the liquid is discharged from the gap. Can be improved.

  In the liquid ejection device according to a seventh aspect of the present invention, in any one of the first to sixth aspects, a gap is further formed between the liquid ejection head and the housing member, and the gas supply means is By supplying gas to the space, the gas is blown out from both the gap between the adjacent liquid discharge heads and the gap between the liquid jet head and the housing member. .

  According to this aspect, gas is blown out from both the gap between the adjacent liquid discharge heads and the gap between the liquid jet head and the housing member. Not only the liquid that has entered the gap but also the discharge of the liquid that has entered the gap between the liquid ejecting head and the housing member can be promoted. In addition, entry of liquid into the gap between the liquid ejecting head and the housing member can be suppressed.

  According to an eighth aspect of the present invention, in the liquid ejection device according to any one of the first to seventh aspects, the gas supply means is disposed in the space during the flushing operation of ejecting the liquid from the liquid ejection head. It is characterized by supplying gas.

  According to this aspect, during the flushing operation, the gas supply means supplies the gas to the space, so that a gas flow can be formed along the liquid discharge direction, and the liquid discharged from the liquid discharge head Can be suppressed from rising as a mist.

  The liquid ejection apparatus according to a ninth aspect of the present invention is characterized in that, in the second aspect, the wiper wipes the nozzle surface in a state where the gas is blown out from the gap.

  According to this aspect, since the wiper wipes the nozzle surface in a state where the gas is blown out from the gap, the liquid wiped by the wiper from the nozzle surface enters the gap. It can be reliably suppressed.

  According to a tenth aspect of the present invention, in the ninth aspect, the liquid ejecting apparatus according to the ninth aspect is a cap means capable of taking a sealed state pressed against the nozzle surface of the liquid ejecting head and a separated state spaced apart from the nozzle surface. In a sealed state in which the cap means is pressed against the nozzle surface, a negative pressure is generated in the cap means, the liquid is sucked from the nozzle on the nozzle surface, and after the liquid is sucked, the sealing is performed The wiping is performed by changing the cap means in a state to a separated state separated from the nozzle surface.

  For example, when wiping is executed in a state where the gas is not blown out, the liquid may enter the gap due to the wiping. Then, it is necessary to blow out the gas into the gap to discharge the liquid from the gap, and then perform wiping again. That is, an extra operation occurs in the maintenance operation. According to this aspect, since the nozzle surface is wiped by the wiper in a state where the gas is blown out from the gap, the liquid can be prevented from entering the gap. Therefore, wiping while blowing out the gas does not cause an extra operation in the maintenance operation, so that the workability of the maintenance of the liquid discharge head can be improved.

1 is an external perspective view showing a printer according to the present invention. FIG. 3 is a side sectional view showing a paper conveyance path of the printer according to the invention. FIG. 2 is a block diagram illustrating a configuration of a printer according to the invention. The perspective view which looked at the line head concerning the present invention from the upper part side. The perspective view which looked at the line head concerning the present invention from the nozzle surface side. The disassembled perspective view of the line head which concerns on this invention. FIG. 3 is an external perspective view of a head unit. The figure explaining attachment of the head unit to a housing member. The figure explaining the attachment state of the head unit to a housing member. The elements on larger scale which show the relationship between the head unit and housing member in the line head which concerns on this invention. FIG. 4 is a side sectional view showing a relationship between a head unit and a housing member in the line head according to the present invention. The figure which shows the 1st state of the maintenance operation | movement in a line head. The figure which shows the 2nd state of the maintenance operation | movement in a line head. The figure which shows the 3rd state of the maintenance operation | movement in a line head. The figure which shows the 4th state of the maintenance operation | movement in a line head. The figure which shows the 5th state of the maintenance operation | movement in a line head. The maintenance operation flowchart figure in a line head. The figure which shows the flushing operation | movement in a line head.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, about the same structure in each Example, the same code | symbol is attached | subjected and it demonstrates only in the first Example, The description of the structure is abbreviate | omitted in a subsequent Example.

  FIG. 1 is an external perspective view showing a printer according to the present invention, FIG. 2 is a side sectional view showing a paper conveyance path of the printer according to the present invention, and FIG. 3 is a block diagram showing the configuration of the printer according to the present invention. 4 is a perspective view of the line head according to the present invention as viewed from above, FIG. 5 is a perspective view of the line head according to the present invention as viewed from the nozzle surface side, and FIG. It is a disassembled perspective view of the line head which concerns.

  7 is an external perspective view of the head unit, FIG. 8 is a diagram for explaining the attachment of the head unit to the housing member, and FIG. 9 is a diagram for explaining the attachment state of the head unit to the housing member. 10 is a partially enlarged view showing the relationship between the head unit and the housing member in the line head according to the present invention, and FIG. 11 is a side sectional view showing the relationship between the head unit and the housing member in the line head according to the present invention. FIG. 12 is a diagram showing a first state of the maintenance operation in the line head.

  13 is a diagram showing a second state of the maintenance operation in the line head, FIG. 14 is a diagram showing a third state of the maintenance operation in the line head, and FIG. 15 is a fourth state of the maintenance operation in the line head. FIG. 16 is a diagram showing a fifth state of the maintenance operation in the line head, FIG. 17 is a flowchart of the maintenance operation in the line head, and FIG. 18 is a diagram showing the flushing operation in the line head. It is.

  In the XYZ coordinate system shown in each figure, the X direction (device width direction) is the full paper width direction, the Y direction is the paper transport direction, and the Z direction is the distance (gap) between the recording head and the paper. The direction of the change, that is, the height direction of the apparatus is shown. In each figure, the −X direction is the front side of the apparatus, and the + X direction side is the back side of the apparatus.

<<< Printer overview >>>
An ink jet printer 10 (hereinafter referred to as a printer 10) as an example of a liquid ejection apparatus will be described with reference to FIG. The printer 10 is configured as a multifunction machine including an apparatus main body 12 and a scanner unit 14. The apparatus main body 12 includes a plurality of paper storage cassettes 16 for storing paper. Each sheet storage cassette 16 is detachably attached from the front side (the −X axis direction side in FIG. 1) of the apparatus main body 12. In this specification, the paper P refers to paper such as plain paper, cardboard, and photographic paper as an example.

  Further, in the apparatus height direction (Z-axis direction) in the apparatus main body 12, a sheet receiving tray 20 that receives the sheet P on which recording is performed by a line head 18 described later is provided between the scanner unit 14 and the sheet storage cassette 16. Is provided.

<<< About the paper transport path >>>
Next, the conveyance path of the paper P in the printer 10 will be described with reference to FIG. In FIG. 2, reference numerals are given only to the main components of the transport path of the paper P, and in particular, reference numerals are omitted for a plurality of spurs.

  The printer 10 in this embodiment includes a paper transport path 22. The sheet conveyance path 22 includes a straight path 24, a switchback path 26, a reverse path 28, a face-down discharge path 30, and a feeding path 32 connected to the straight path 24 from the sheet storage cassette 16.

  In the feeding path 32, a feeding roller 34, a separation roller pair 36, and a first conveying roller pair 38 are provided in order along the conveyance direction of the paper P. The feed roller 34 is driven to rotate by a drive motor (not shown). The separation roller pair 36 separates the paper P by nipping the paper P. The first transport roller pair 38 is configured as a drive roller in which one roller is rotated by a drive motor (not shown), and the other roller is configured as a driven roller.

  In the following description, it is assumed that one roller in each pair of transport rollers appearing in this specification is configured as a drive roller that is driven to rotate by a drive motor (not shown), and the other roller is configured as a driven roller. explain.

  The paper P stored in the paper storage cassette 16 is fed to the downstream side of the feeding path 32 by the feeding roller 34. The paper P fed by the feed roller 34 is sequentially nipped by the separation roller pair 36 and the first transport roller pair 38 and fed toward the downstream side of the feed path 32. A second transport roller pair 40 is provided on the downstream side of the first transport roller pair 38 in the transport direction.

  In the present embodiment, the feeding path 32 and the straight path 24 are connected at the position of the second transport roller pair 40. That is, the feeding path 32 is set as a path from the sheet storage cassette 16 to the second transport roller pair 40.

  The straight path 24 is configured as a linearly extending path, and the second transport roller pair 40, the third transport roller pair 42, the line head 18, the fourth transport roller pair 44, and the first flap 46 are sequentially arranged along the transport direction. Is provided. In this embodiment, the straight path 24 is set as a path from the second conveying roller pair 40 to the first flap 46. That is, the straight path 24 is set as a path that passes through the line head 18 and extends upstream and downstream of the line head 18.

  The line head 18 is configured to perform recording by ejecting ink as “liquid” onto the recording surface of the paper P when the paper P is conveyed to an area facing the line head 18. The line head 18 in this embodiment is a recording head provided so that nozzles that eject ink cover the entire area in the sheet width direction as an example, and recording is performed on the entire sheet width without moving in the sheet width direction. It is configured as a possible recording head. The configuration of the line head 18 will be described in detail later.

  Subsequently, the first flap 46 is positioned downstream of the line head 18 in the transport direction. The first flap 46 is configured to be swingable by a drive mechanism controlled by a control unit 74 (see FIG. 3) provided in the apparatus main body 12. The first flap 46 can switch between a posture (state of FIG. 2) connecting the straight path 24 and the switchback path 26 and a posture (not shown) connecting the straight path 24 and the face-down discharge path 30. It is configured. In this embodiment, the drive mechanism for driving the first flap 46 is constituted by a solenoid. The posture switching operation of the first flap 46 is controlled by the control unit 74 (see FIG. 3).

  When the first flap 46 is in a posture (not shown) that connects the straight path 24 and the face-down discharge path 30, the paper P is sent from the straight path 24 to the face-down discharge path 30 by the fourth transport roller pair 44.

  The face-down discharge path 30 is curved and inverted while extending upward from the straight path 24 in the apparatus height direction. The face-down discharge path 30 includes a fifth transport roller pair 48, a sixth transport roller pair 50, a seventh transport roller pair 52, an eighth transport roller pair 54, a ninth transport roller pair 56, and a tenth transport roller pair 58. It has.

  The face-down discharge path 30 is routed from the first flap 46 to the outlet 60 located downstream in the transport direction of the tenth transport roller pair 58. That is, the face-down discharge path 30 is a conveyance path that is connected to the straight path 24, and is a path that discharges the paper P that has passed through the line head 18 after being bent and inverted.

  The sheet P on which recording is performed on the recording surface by the line head 18 is sequentially performed from the first flap 46 along the transport direction in the face-down discharge path 30 in the order of the fifth transport roller pair 48, the sixth transport roller pair 50, and the seventh. A pair of transport rollers 52, an eighth transport roller pair 54, a ninth transport roller pair 56, and a tenth transport roller pair 58 are sequentially nipped and transported. Then, the paper P is discharged from the outlet 60 toward the paper receiving tray 20.

  Here, when the sheet P is conveyed along the face-down discharge path 30, the sheet P is finally conveyed with the recording surface recorded by the line head 18 facing upward, and then the recording surface is transferred to the curved portion of the face-down discharge path 30. The sheet is curved inward and conveyed, and discharged from the outlet 60 toward the sheet receiving tray 20 with the recording surface facing downward.

<<< Conveying path of paper in double-sided recording >>>
When the first flap 46 is in a posture for connecting the straight path 24 and the switchback path 26 (see FIG. 2), the paper P is sent from the straight path 24 to the switchback path 26 by the fourth transport roller pair 44.

  The switchback path 26 and the reverse path 28 are paths through which the sheet P passes when recording on the second side after recording on the first side of the sheet P, that is, when executing double-sided recording. Similarly, when recording is performed on the second side although recording is not performed on the first side, the paper P passes through the switchback path 26 and the reverse path 28. That is, in this specification, double-sided recording means that paper P is reversed and recording is performed on the second side regardless of whether recording is performed on the first side.

  The switchback path 26 is located inside the face-down discharge path 30 that is curved and inverted upward in the apparatus height direction, and extends along the face-down discharge path 30. The switchback path 26 includes an eleventh transport roller pair 62.

  In this embodiment, the switchback path is set as a path from the second flap 64 provided above the first flap 46 to the opening 66 provided at the tip of the switchback path 26. When the switchback path 26 is connected to the straight path 24 by the first flap 46 (see FIG. 2), the paper P passes through the first flap 46 from the region facing the line head 18 by the fourth transport roller pair 44. It is sent to the switchback path 26. The paper P is fed to a position where the rear end portion in the transport direction is nipped by the eleventh transport roller pair 62 in the switchback path 26.

  Here, the second flap 64 will be described. The second flap 64 is provided above the first flap 46 in the apparatus height direction (Z-axis direction). The second flap 64 is swung by an interlocking mechanism (not shown) in conjunction with the operation of the first flap 46. That is, the second flap 64 is controlled by the control unit 74 via the first flap 46 and the interlocking mechanism.

  The second flap 64 is configured to block the connection between the switchback path 26 and the reversing path 28 in a state where the first flap 46 connects the straight path 24 and the switchback path 26 (see FIG. 2). On the other hand, in a state where the first flap 46 connects the straight path 24 and the face-down discharge path 30, the second flap 64 is in a posture to connect the switchback path 26 and the reverse path 28.

  When the second flap 64 takes a posture to connect the switchback path 26 and the reversing path 28, the control unit 74 rotates the eleventh transport roller pair 62 in the direction opposite to the direction in which the paper P is fed to the switchback path 26. The paper P is sent out to the reversing path 28 with the rear end side of the paper P as the front end side. That is, the paper P is switched back.

  The inversion path 28 is set as a path from the second flap 64 to the second transport roller pair 40 of the straight path 24 through the line head 18. The reverse path 28 includes a twelfth transport roller pair 68, a thirteenth transport roller pair 70, and a fourteenth transport roller pair 72.

  The exit side of the reversing path 28 is configured to join the straight path 24 at a position upstream of the second transport roller pair 40 in the straight path 24. Then, the paper P is fed again into the straight path 24. In other words, the reverse path 28 is a transport path connected to the switchback path 26, and reverses the sheet P transported in the reverse direction, that is, the switched back sheet P by bypassing the upper side of the line head 18, so Is set as a path to be joined by the second transport roller pair 40 located at the upstream position of the line head 18.

  Then, when the paper P is transported through the reversing path 28, the first surface and the second surface are reversed, transported to an area facing the line head 18 in the straight path 24, and recording is performed on the second surface. Is done. Thereafter, the paper P is discharged to the paper receiving tray 20 through the face-down discharge path 30.

<<< About the control unit >>>
The apparatus main body 12 includes a control unit 74 (see FIG. 3) as an electric circuit composed of a plurality of electronic components. The control unit 74 includes the scanner unit 14, the line head 18, the first flap 46, the second flap 64, the motor driver 76, the gas supply means 94, and the paper P feeding, conveying, discharging, recording operation, and document reading in the wiper 116. Operations necessary for recording and image reading of the printer 10 such as operations and maintenance operations are controlled.

  Further, the control unit 74 may control operations necessary for execution of recording and image reading of the printer 10 such as a document reading operation by an instruction from the outside (PC or the like). Further, the control unit 74 controls the ejection of ink in the line head 18.

  A plurality of motor drivers 76 controlled by the control unit 74 are arranged in the apparatus main body 12 and control a plurality of drive motors (not shown). That is, the control unit 74 drives the transport roller pairs from the feed roller 34, the separation roller pair 36, and the first transport roller pair 38 to the fourteenth transport roller pair 72 via the motor driver 76 and the plurality of drive motors. Is controlling.

■■■ Example ■■■■
<<< About the configuration of the line head >>>
The configuration of the line head 18 will be described with reference to FIGS. The line head 18 is housed in a housing member 78 and includes a plurality of head units 80 as “liquid ejection heads” covered with the housing member 78. Referring to FIG. 6, in this embodiment, the housing member 78 includes an upper housing member 82 and a lower housing member 84. 5 and 6, some symbols are omitted for explanation.

  A plurality of head units 80 are attached to the lower housing member 84 so that the nozzle surface 80a is exposed outside the housing member 78 (see FIG. 5). In addition, on the side opposite to the nozzle surface 80a in the head unit 80, that is, the upper surface, ink connectors 86 for supplying ink into the head unit 80 are provided corresponding to the number of ink colors. In this embodiment, the ink colors are black, magenta, yellow, and cyan, for example, so that four ink connectors 86 are provided.

  An ink supply member 88 is provided on the upper surface 80 b of the plurality of head units 80. In the present embodiment, four ink supply members 88 are provided corresponding to the ink colors. Each ink supply member 88 is connected to an ink connector 86 having the same color as the ink to be supplied. In the present embodiment, the ink supply member 88 is connected to the ink connectors 86 of the respective colors provided in the six head units 80.

  One end of the ink supply member 88 is connected to an ink tube 90 that penetrates the upper housing member 82. The ink tube 90 is provided in the apparatus main body 12 and is connected to an ink tank (not shown) that stores ink of the same color as the color of the ink connector 86.

  Therefore, the ink stored in the ink tank (not shown) is supplied to each head unit 80 via the ink tube 90, the ink supply member 88, and the ink connector 86. The ink supplied to the head unit 80 is ejected toward the recording surface of the paper P from the nozzle corresponding to the ink color among the plurality of nozzles provided on the nozzle surface 80a.

  A gas supply tube 92 is provided on the upper surface 82 a of the upper housing member 82. Referring to FIG. 15, one end of the gas supply tube 92 is connected to the gas supply means 94, and the other end passes through the upper surface 82 a of the upper housing member 82 and is formed in the housing member 78. 96 protrudes. Further, the gas supply means 94 is controlled by the controller 74 with respect to the supply amount, supply timing, supply pattern, and the like of the gas supplied to the space 96.

  In addition, the space 96 in the present embodiment includes the head unit 80 and the ink supply member 88 in the housing member 78 in addition to the case where the housing member 78 is formed as a dedicated space for storing gas in the housing member 78. Thus, a space formed in the housing member 78 is also included.

<< Gap between head unit and gap between head unit and housing member >>
Next, with reference to FIG. 7 to FIG. 11, the step of attaching the head unit to the housing member, the gap between the head units, and the gap between the head unit and the housing member will be described.

  Referring to FIG. 7, the head unit 80 includes a head portion 98 provided with a nozzle surface 80a and a main body portion 100. The lower surface of the head portion 98 forms a nozzle surface 80a. In the present embodiment, the head portion 98 is formed in a prismatic shape as an example, and has side portions 98a, 98b, 98c, and 98d. Further, a mounting portion 102 is formed on the main body portion 100. In the present embodiment, the mounting portion 102 is provided with a plurality of holes 104. Note that the dots (black dots) drawn on the nozzle surface 80a in FIG. 7 are examples of a plurality of nozzles provided on the nozzle surface 80a, and the position, arrangement, etc. of the nozzles are changed as appropriate according to the specifications. Is done.

Referring to FIG. 8, the lower housing member 84 is provided with a head opening 84a.
The head opening portion 84 a corresponds to the shape of the head portion 98, and is opened so that the nozzle surface 80 a is exposed to the outside of the housing member 78 when the head unit 80 is attached to the lower housing member 84. Further, the upper surface 84 b of the lower housing member 84 engages with the attachment portion 102 of the head unit 80 when the head unit 80 is attached to the lower housing member 84. A plurality of fastening holes 106 are provided on the upper surface 84b. In this embodiment, the fastening hole 106 is configured as a screw hole.

  FIG. 9 shows a state where a plurality of head units 80 are attached to the lower housing member 84. The lower housing member 84 is provided with a reference surface 84c in the X-axis direction and a reference surface 84d in the Y-axis direction in FIG.

  Each head unit 80 is positioned with respect to the lower housing member 84 while confirming the positions of a plurality of nozzles provided on the nozzle surface 80a with respect to the reference surface 84c and the reference surface 84d by an optical observation means such as a camera. Each head unit 80 is attached to the lower housing member 84 by fastening the fastening member 105 (see FIG. 11) with the fastening hole 106 of the lower housing member 84 through the hole 104 of the head unit 80. In this embodiment, the fastening member 105 is configured as a screw.

  In this embodiment, the diameter of the hole 104 is set larger than the diameter of the fastening portion of the fastening member 105. As a result, the mounting portion 102 of the head unit 80 is engaged with the upper surface 84b of the lower housing member 84, the screw as the fastening member 105 is passed through the hole 104, and the fastening member 105 is temporarily tightened into the fastening hole 106 as the screw hole. In this state, the position of the head unit 80 with respect to the lower housing member 84 can be finely adjusted.

  Here, FIG. 10 shows, as an example, a head unit 80A and a head unit 80B that are positioned with respect to the lower housing member 84 and attached to the lower housing member 84, respectively. In FIG. 10, a gap 108 is formed between the head unit 80A and the head unit 80B. Specifically, a gap 108 having a width D3 is formed between the side portion 98a of the head unit 80A and the side portion 98c of the head unit 80B. As shown in FIG. 15, the gap 108 extends from the nozzle surface 80 a side of the head unit 80 to the upper surface 80 b and communicates with a space 96 in the housing member 78. The width D3 of the gap 108 is defined when the head unit 80 is attached to the lower housing member 84.

  Further, gaps 110 are also formed between the lower housing member 84 and the side portions 98b, 98c, 98d of the head unit 80A and the side portions 98b, 98d of the head unit 80B. In the present embodiment, as an example, the gap 110 between the lower housing member 84 and the side portion 98b of the head unit 80A is formed with a width D2, and the gap 110 between the lower housing member 84 and the side portion 98c of the head unit 80A has a width D1. The gap 110 between the lower housing member 84 and the side portion 98d of the head unit 80A is formed with a width D4, and the gap 110 between the lower housing member 84 and the side portion 98b of the head unit 80B is formed with a width D5. A gap 110 between the housing member 84 and the side portion 98d of the head unit 80B is formed with a width D6.

  In this embodiment, the widths D 1, D 2, D 4, D 5, and D 6 of the gap 110 are defined when the head unit 80 is attached to the lower housing member 84. Further, in this embodiment, of the gap 110, the gap 110 between the lower housing member 84 and the side portion 98 c of the head unit 80 A extends from the nozzle surface 80 a side of the head unit 80 to the upper surface 80 b, and is a space 96 in the housing member 78. Communicating with Further, the gap 110 between the lower housing member 84 and the side portions 98b and 98d of the head unit 80A is a space through the gap 108 between the head units 80 and the gap 110 between the lower housing member 84 and the side portion 98c of the head unit 80A. 96.

  Further, the gap 108 and the gap 110 are exposed to the outside of the housing member 78 in a state where the head unit 80 is attached to the lower housing member 84. That is, the space 96 in the housing member 78 communicates with the outside of the housing member 78 through the gap 108 and the gap 110. Therefore, when the gas supply means 94 supplies gas to the space 96 via the gas supply tube 92, the supplied gas blows out toward the outside of the housing member 78 through the gap 108 and the gap 110. The gas in a present Example is air as an example. In this embodiment, the air pressure in the space 96 is set higher than the air pressure outside the housing member 78.

<<< About the maintenance operation of the line head >>>
Next, the maintenance operation of the line head 18 will be described with reference to FIGS. For the sake of explanation in FIGS. 12 to 17, some reference numerals are omitted. In addition, the housing member 78 is not shown in FIGS.

  In FIG. 12, cap means 112 is provided in the apparatus main body 12. The cap means 112 is configured to be able to switch between a state located below each head unit 80 of the line head 18 and a state retracted from below the head unit 80. Further, the cap means 112 is configured to be able to contact and separate from the nozzle surface 80 a of each head unit 80 while being positioned below the line head 18. Specifically, the cap unit 112 can take a sealed state pressed against the nozzle surface 80a of the head unit 80 and a separated state separated from the nozzle surface 80a.

  Further, as shown in FIG. 13, the cap unit 112 can be made to have a negative pressure in the cap unit 112 by a pump (not shown) in a state of being in close contact with the nozzle surface 80a of the head unit 80, and is provided on the nozzle surface 80a. Ink remaining in the nozzles can be sucked. The sucked ink is stored in a waste ink storage unit 114 connected to the cap unit 112. The waste ink container 114 is provided in the apparatus main body 12.

  Also, as shown in FIGS. 12 to 16, a flexible wiper 116 is provided in the apparatus main body 12. A waste ink receiver 118 is provided below the wiper 116. In this embodiment, the wiper 116 and the waste ink receiver 118 are configured to be movable relative to the line head 18. In this embodiment, the wiper 116 and the waste ink receiver 118 are configured to be movable in the paper width direction (X-axis direction in FIGS. 15 and 16).

  Here, the flow of the maintenance operation of the line head 18 will be described based on the flowchart shown in FIG. In step S1, the cap means 112 provided in the apparatus main body 12 is moved below the line head 18 (see FIG. 12). In step S <b> 2, the control unit 74 confirms whether or not the cap unit 112 is positioned below the line head 18.

  If the movement of the cap unit 112 has not ended, the control unit 74 continues the movement of the cap unit 112 as step S3. When the downward movement of the cap unit 112 of the line head 18 is completed, the cap unit 112 is moved to the nozzle surface 80a side of the head unit 80 in step S4, and the cap unit 112 is brought into close contact with the nozzle surface 80a (FIG. 13).

  In step S5, a pump (not shown) is driven to bring the cap means 112 into a negative pressure state, and the ink remaining in the nozzles provided on the nozzle surface 80a is sucked (see FIG. 13). In step S6, the cap means 112 is separated from the nozzle surface 80a (FIG. 14). Then, the ink accumulated in the cap unit 112 is sent to the waste ink storage unit 114 and the waste ink is stored in the waste ink storage unit 114. The waste ink can be sent from the cap unit 112 to the waste ink storage unit 114 simultaneously with the suction operation in step S5.

  In step S7, the cap means 112 is retracted from the position below the line head 18 (see FIG. 15). In step S8, gas is supplied from the gas supply means 94 to the space 96 in the housing member 78 through the gas supply tube 92 (see FIG. 15). As a result, the gas supplied to the space 96 passes through the gap 108 and the gap 110 and blows out from the gap 108 and the gap 110 toward the outside of the housing member 78, that is, in the ink discharge direction of the head unit 80. In this embodiment, the gas supply means 94 is controlled by the control unit 74 so as to supply a constant amount of gas continuously to the space 96.

  Next, in step S9, the wiper 116 and the waste ink receiver 118 are moved in the paper width direction, that is, the longitudinal direction of the line head 18 in a state where they are in contact with the nozzle surface 80a, and wiping is performed (see FIG. 16). Thereby, the ink remaining on the nozzle surface 80 a is scraped off by the wiper 116. A part of the ink scraped off by the wiper 116 is accommodated in a waste ink receiver 118 located below the wiper 116.

  Further, during the wiping operation of the wiper 116, the gas is blown out from the gap 108 and the gap 110, so that the ink scraped by the wiper 116 can be prevented from entering the gap 108 and the gap 110.

  As step S10, the control unit 74 confirms whether or not the movement of the wiper 116, that is, the wiping operation is completed. If the control unit 74 determines that the wiping operation of the wiper 116 has not ended, the movement of the wiper 116 is continued in step S11.

  When the control unit 74 determines that the wiping operation of the wiper 116 has been completed, the control unit 74 controls the gas supply unit 94 to stop the supply of gas to the space 96 in step S12.

<<< About flushing action >>>
The flushing operation will be described with reference to FIG. In this embodiment, as an example, the ink receiver for the flushing operation uses the cap unit 112.

  In a state where the cap unit 112 is positioned below the line head 18, the control unit 74 supplies gas from the gas supply unit 94 to the space 96. The gas supplied to the space 96 passes through the gap 108 and the gap 110 and blows out from the gap 108 and the gap 110 toward the outside of the housing member 78. At this time, the gas blown out from the gap 108 and the gap 110 blows out toward the ink discharge direction of the head unit 80 and forms a gas flow along the ink discharge direction. In this embodiment, as an example, gas is blown out from the entire circumference of the head portion 98 of the head unit 80.

  Next, the control unit 74 discharges ink from the nozzles provided on the nozzle surface 80 a of the head unit 80 in a state where gas is blown out from the gap 108 and the gap 110. The ink ejected from the nozzles is accommodated in the cap unit 112 located below the head unit 80.

  In the present embodiment, the gas blown from the gap 108 and the gap 110 forms a flow along the liquid discharge direction during the flushing operation, so that the ink discharged from the head unit 80 can be suppressed from rising as a mist. .

  Further, when the above description is summarized, since the gas is blown out from the space 96 to the outside of the housing member 78 through the gaps 108 and 110 in the printer 10, it is possible to prevent ink from entering the gaps 108 and 110. Alternatively, since the ink that has entered the gaps 108 and 110 can be discharged, it is possible to eliminate problems caused by the ink entering the gaps. And the structure of such a printer 10 can be simplified and the enlargement of the printer 10 can be suppressed. In addition, since the configuration of the printer 10 can be simplified, the maintainability of the printer 10 can be improved.

  In this embodiment, the air pressure in the space 96 is set higher than the air pressure outside the housing member 78, so that the gas surely flows from the inside of the housing member 78 to the outside of the housing member 78 in the gaps 108 and 110. Therefore, it is possible to reliably suppress the ink from entering the gaps 108 and 110, and it is possible to reliably discharge the ink that has entered the gaps 108 and 110.

  Further, in this embodiment, gas blows out from both the gap 108 between the adjacent head units 80 and the gap 110 between the head unit 80 and the lower housing member 84, so that the gap between the adjacent head units 80 is Not only ink that has entered the gap 108 but also discharge of ink that has entered the gap 110 between the head unit 80 and the lower housing member 84 can be urged. Further, ink can be prevented from entering the gap 110 between the head unit 80 and the lower housing member 84.

  Further, in the present embodiment, the wiper 116 wipes the nozzle surface 80a in a state where gas is blown out from the gaps 108 and 110. Therefore, the ink wiped by the wiper 116 from the nozzle surface 80a enters the gaps 108 and 110. This can be suppressed more reliably.

  In the present embodiment, the nozzle surface 80a is wiped by the wiper 116 in a state where gas is blown out from the gaps 108 and 110. For example, when wiping is executed in a state where gas is not blown out from the gaps 108 and 110 Then, ink may enter the gaps 108 and 110 by wiping. Then, it is necessary to blow gas into the gaps 108 and 110 to discharge the ink from the gaps 108 and 110, and then perform wiping again. On the other hand, in this embodiment, it is possible to prevent ink from entering the gaps 108 and 110. Therefore, wiping while blowing gas from the gaps 108 and 110 does not cause an extra operation in the maintenance operation of the line head 18, so that the maintenance workability of the head unit 80 can be improved.

■■■ Example changes ■■■■
(1) In this embodiment, the width of the gap 108 is configured to be a constant width from the nozzle surface 80a side to the upper surface 80b of the head unit 80 (see FIG. 15), but instead of this configuration, the gap 108 is formed on the nozzle surface 80a side. It is good also as a structure which becomes large as it goes to the space 96 side from. With this configuration, even if ink enters the nozzle surface 80a side in the gap 108, the gap 108 increases from the nozzle surface 80a side to the space 96 side, so that capillary action is unlikely to occur, and the ink is not in the gap. Intrusion to the space 96 side of 108 can be suppressed.

(2) In the present embodiment, the gas supply means 94 is controlled so as to supply a constant amount of gas continuously to the space 96, but may be controlled to supply gas intermittently to the space 96. . Thus, by intermittently supplying the gas to the space 96, the gas is intermittently blown out of the housing member 78 through the gap 108. As a result, for example, even when a highly viscous liquid enters the gap 108, the gas is intermittently blown to the ink to give vibration, so that the ink dischargeability from the gap 108 can be improved.

(3) In this embodiment, the gas supply means 94 is controlled so as to supply a constant amount of gas continuously to the space 96, but the amount of gas supplied to the space 96 is periodically increased or decreased. You may control. Thus, by periodically increasing or decreasing the amount of gas supplied to the space 96, the flow rate of the gas blown out from the space 96 toward the outside of the housing member 78 through the gap 108 is periodically increased or decreased. As a result, for example, even when highly viscous ink enters the gap 108, the ink is vibrated by periodically increasing and decreasing the flow rate of the gas blown to the ink, so that the ink discharge performance from the gap 108 is improved. be able to.

(4) In this embodiment, the gas supplied from the gas supply means 94 is air, but it may be a gas such as nitrogen gas or oxygen gas.
(5) In this embodiment, the wiping operation is performed in a state where gas is blown out from the gaps 108 and 110. Instead of this configuration, the wiping operation is performed in a state where gas is not blown out from the gaps 108 and 110. In this case, after the wiping operation, gas may be blown out from the gaps 108 and 110 to discharge the liquid that has entered the gaps 108 and 110, and then rewiping may be performed.

(6) In the flushing operation in this embodiment, the gas is blown out from the entire circumference of the head portion 98 of the head unit 80, that is, the gaps 108 and 110. It is good also as a structure which blows off gas from one part clearance gap.
(7) In the present embodiment, the plurality of head units 80 are arranged in a staggered pattern on the housing member 78. However, the head units 80 may be arranged in a line in the longitudinal direction of the line head 18, and other appropriate cases. A configuration may be adopted in which the orientation, arrangement pattern, outer shape, and the like of the plurality of head units 80 are changed.

(8) In this embodiment, the wiping operation is performed in a state where gas is blown out from the gaps 108 and 110. However, instead of this configuration, the gaps 108 and 110 are always provided when the printer 10 is turned on. It is good also as a structure which blows off gas from.
(9) In this embodiment, the wiping operation is performed in a state where the gas is blown out from the gaps 108 and 110. However, instead of this configuration, the gap is changed according to the number of recording sheets P and the operation time of the printer 10. It is good also as a structure which blows off gas from 108,110.

(10) In this embodiment, the wiping operation is performed in a state where gas is blown out from the gaps 108 and 110. However, instead of this configuration, the gas is supplied from the gaps 108 and 110 before the suction operation of the cap unit 112. It is good also as a structure made to blow out.
(11) Ink repellent treatment may be applied to the surfaces of the head unit 80 and the housing member 78 constituting the gaps 108 and 110 in this embodiment.

  To summarize the above description, the printer 10 includes a plurality of head units 80 that are arranged with a suitable gap 108 and that eject ink, and at least the gap 108 and the nozzle surface 80a of the head unit 80 are exposed. Gas that blows gas from the space 96 to the outside of the housing member 78 through the gap 108 by supplying the gas to the housing member 78 that covers 80 and the space 96 that communicates with the gap 108 in the housing member 78. Supply means 94.

  In addition, the printer 10 includes a wiper 116 that wipes the nozzle surface 80 a of the head unit 80. Further, the pressure in the space 96 is higher than the pressure outside the housing member 78.

Further, the gap 108 becomes larger from the nozzle surface 80a side toward the space 96 side.
Further, the gas supply means 94 may supply the gas intermittently to the space 96, and may periodically increase or decrease the amount of gas supplied to the space 96.

  In the printer 10, a gap 110 is further formed between the head unit 80 and the lower housing member 84. The gas supply means 94 supplies gas to the space 96 so that the gas blows out from both the gap 108 between the adjacent head units 80 and the gap 110 between the head unit 80 and the lower housing member 84. It has.

  During the flushing operation of ejecting ink from the head unit 80 in the printer 10, the gas supply means 94 supplies the gas to the space 96. The wiper 116 wipes the nozzle surface 80a in a state where gas is blown out from the gaps 108 and 110.

  The printer 10 includes a cap unit 112 that can take a sealed state pressed against the nozzle surface 80a of the head unit 80 and a separated state separated from the nozzle surface 80a. In the maintenance operation of the printer 10, in a sealed state in which the cap unit 112 is pressed against the nozzle surface 80 a, a negative pressure is generated in the cap unit 112, the ink is sucked from the nozzles on the nozzle surface 80 a, and the ink is sucked and sealed. Wiping is performed by changing the cap means 112 in the stopped state to a separated state separated from the nozzle surface 80a.

  In the above embodiment, the line head 18 as a liquid discharge head is a type that discharges liquid in a fixed state without moving. However, the present invention is not limited to this, and the liquid discharge head moves while moving in a predetermined direction. The present invention can also be applied to a type in which ink is ejected from the nozzles of the head.

In this embodiment, the line head 18 according to the present invention is applied to a recording apparatus as an example of a liquid ejection apparatus, and further to an ink jet printer as an example of the liquid ejection apparatus. However, the present invention can be applied to other liquid ejection apparatuses in general.
Here, the liquid ejecting apparatus uses an ink jet recording head, and ejects ink from the recording head to perform recording on a recording medium as an example of a medium to be ejected (medium on which liquid is ejected). It is not limited to printers, copiers and facsimiles to be performed. That is, instead of ink, a liquid corresponding to the application is ejected from a liquid ejection head corresponding to the ink jet recording head to a ejection medium corresponding to a recording medium, and the liquid is attached to the ejection medium. Including the device.

  In addition to the recording head, as a liquid ejecting head, a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, and an electrode material (conductive paste) used for forming an electrode such as an organic EL display or a surface emitting display (FED) Examples thereof include an ejection head, a bioorganic matter ejection head used for biochip production, and a sample ejection head as a precision pipette.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

10 Printer, 12 Main body, 14 Scanner unit,
16 paper cassette, 18 line head, 20 paper tray,
22 paper transport path, 24 straight path, 26 switchback path,
28 Reverse path, 30 Face down discharge path, 32 Feed path, 34 Feed roller,
36 pair of separation rollers, 38 first transport roller pair, 40 second transport roller pair,
42 3rd conveyance roller pair, 44 4th conveyance roller pair, 46 1st flap,
48 5th conveyance roller pair, 50 6th conveyance roller pair, 52 7th conveyance roller pair,
54 eighth transport roller pair, 56 ninth transport roller pair, 58 tenth transport roller pair,
60 outlet, 62 eleventh conveying roller pair, 64 second flap, 66 opening,
68 12th transport roller pair, 70 13th transport roller pair,
72 14th conveying roller pair, 74 control unit, 76 motor driver,
78 Housing member, 80, 80A, 80B Head unit, 80a Nozzle surface,
80b, 82a, 84b upper surface, 82 upper housing member, 84 lower housing member,
84a Head opening, 84c, 84d Reference plane, 86 Ink connector,
88 ink supply member, 90 ink tube, 92 gas supply tube,
94 gas supply means, 96 spaces, 98 heads,
98a, 98b, 98c, 98d side part, 100 body part, 102 mounting part, 104 holes,
105 fastening members, 106 fastening holes, 108, 110 gaps, 112 cap means,
114 waste ink container, 116 wiper, 118 waste ink receiver,
D1, D2, D3, D4, D5, D6 width, P paper,
Steps S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11, S12

Claims (10)

A plurality of liquid ejection heads that eject liquid, with a plurality of appropriate gaps therebetween;
A housing member that covers the plurality of liquid ejection heads with at least the gaps and the nozzle surfaces of the liquid ejection heads exposed;
A gas supply means for blowing gas from the space toward the outside of the housing member via the gap by supplying gas to the space communicating with the gap in the housing member;
A liquid ejection device comprising: The liquid ejection apparatus according to claim 1, further comprising a wiper that wipes the nozzle surface.
A liquid discharge apparatus characterized by that. 3. The liquid ejection apparatus according to claim 1, wherein an air pressure in the space is higher than an air pressure outside the housing member.
A liquid discharge apparatus characterized by that. The liquid ejection device according to any one of claims 1 to 3, wherein the gap increases from the nozzle surface side toward the space side.
A liquid discharge apparatus characterized by that. 5. The liquid ejection device according to claim 1, wherein the gas supply unit intermittently supplies the gas to the space.
A liquid discharge apparatus characterized by that. 5. The liquid ejection device according to claim 1, wherein the gas supply unit periodically increases or decreases the supply amount of the gas to the space.
A liquid discharge apparatus characterized by that. 7. The liquid ejection apparatus according to claim 1, wherein a gap is further formed between the liquid ejection head and the housing member, and the gas supply unit supplies gas to the space. By this, gas is blown out from both the gap between the adjacent liquid discharge heads and the gap between the liquid jet head and the housing member,
A liquid discharge apparatus characterized by that. 8. The liquid ejection apparatus according to claim 1, wherein the gas supply unit supplies the gas to the space during a flushing operation in which the liquid is ejected from the liquid ejection head.
A liquid discharge apparatus characterized by that. The liquid ejecting apparatus according to claim 2, wherein the wiper wipes the nozzle surface in a state where the gas is blown out from the gap.
A liquid discharge apparatus characterized by that. The liquid ejection apparatus according to claim 9, further comprising a cap unit that can take a sealed state pressed against the nozzle surface of the liquid ejection head and a separated state separated from the nozzle surface.
In the sealed state in which the cap means is pressed against the nozzle surface, a negative pressure is generated in the cap means, and the liquid is sucked from the nozzle on the nozzle surface,
After the suction of the liquid, the cap means in the sealed state is changed to a separated state separated from the nozzle surface, and the wiping is performed.
A liquid discharge apparatus characterized by that.

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