JP2016043648A - Inkjet recording device and wiping method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress generation of ink buildup in an ink discharge surface.SOLUTION: The wiping method includes a first wiping step, an ink equalization step and a second wiping step. In the first wiping step, a wiper 20 is used to wipe a range from a first contact position PT1 through an ink adhesion region FA to a first stop position PS1. After the first wiping step, in the ink equalization step, the wiper 20 is moved back by a predetermined distance LB from the first stop position PT1, stopped and separated from an ink discharge surface 17, and then pressed against the first stop position PT1 to be separated again from the ink discharge surface 17. After the ink equalization step, in the second wiping step, the wiper 20 is used to wipe a range from the second contact position PT2 to the second stop position PS2.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an ink jet recording apparatus. The present invention also relates to a wiping method.

  Conventionally, a technique for wiping ink adhering to an ink ejection surface of a recording head with a wiper is known. For example, an ink jet recording apparatus including a plurality of wipers is disclosed (see Patent Document 1).

  Patent Document 1 describes that two wipers (a first wiper and a second wiper) are moved as follows. Here, the second wiper is disposed on the upstream side of the first wiper with respect to the wiping direction of the ink discharge surface. First, the first wiper is brought into pressure contact with the wiping start position outside the nozzle region from a substantially vertical direction, and wipes the ink ejection surface including the nozzle region in a predetermined direction. Next, after the second wiper moves the ink reservoir formed by the ink adhering to the tip of the first wiper during the second and subsequent wiping operations, the ink is discharged on the upstream side of the nozzle area. Separate from the surface.

  As described above, it is described that by causing the two wipers to move, it is possible to suppress the occurrence of ink accumulation on the upstream side from the position at which wiping is started.

JP 2013-49205 A

  However, in the invention described in Patent Document 1, the ink after wiping adheres to the tip of the second wiper, and the ink may reattach to the wiping start position of the second wiper. As a result, the ink that has reattached to the ink ejection surface may dry and fall on the recording paper, resulting in contamination.

  The ink jet recording apparatus and the wiping method according to the present invention have been made in view of the above problems, and an object thereof is to suppress the occurrence of ink accumulation on the ink ejection surface.

  A first inkjet recording apparatus according to the present invention includes a recording head that ejects ink onto a recording medium, a wiper that wipes off ink adhering to the ink ejection surface of the recording head, a moving mechanism that moves the wiper, And a control unit that controls the operation of the wiper via a moving mechanism. The control unit includes a first movement instruction unit and a second movement instruction unit. The first movement instructing unit causes the wiper to perform a first wiping operation and an ink equalizing operation through the moving mechanism. In the first wiping operation, the ink wiper is moved outside the ink adhesion area, which is an area where the ink ejected from the nozzles is adhered, at a first contact position at one end of the recording head. The ink is pressed against the ejection surface and moved to the first stop position at the other end of the recording head along the ink ejection surface via the ink adhesion region. In the ink equalizing operation, after the first wiping operation, the wiper is separated from the ink ejection surface, pressed against the ink ejection surface again at the first stop position, and separated from the ink ejection surface again. . The second movement instruction unit causes the wiper to perform a second wiping operation. In the second wiping operation, after the ink equalizing operation, the wiper is pushed against the ink ejection surface at a second contact position outside the first stop position at the other side end of the recording head. After the contact is moved toward the one end of the recording head along the ink ejection surface, the recording head is stopped at a second stop position outside the recording head from the first contact position. Separate from the ink ejection surface.

  A wiping method according to the present invention is a wiping method for wiping ink adhering to an ink ejection surface of a recording head with a wiper, and a control unit that controls the operation of the wiper is configured to move the wiper through a moving mechanism. It includes a first wiping step, an ink uniformizing step, and a second wiping step for moving the wiper. In the first wiping step, the wiper is placed outside the ink adhesion area, which is an area where the ink ejected from the nozzles is adhered, at a first contact position at one end of the recording head. The ink is pressed against the ejection surface and moved to the first stop position at the other end of the recording head along the ink ejection surface via the ink adhesion region. In the ink uniformizing step, after the first wiping step, the wiper is separated from the ink ejection surface, pressed against the ink ejection surface again at the first stop position, and separated from the ink ejection surface again. . In the second wiping step, after the ink equalization step, the wiper is pushed against the ink ejection surface at a second contact position outside the first stop position at the other side end of the recording head. After the contact is moved toward the one end of the recording head along the ink ejection surface, the recording head is stopped at a second stop position outside the recording head from the first contact position. Separate from the ink ejection surface.

  According to the ink jet recording apparatus and the wiping method of the present invention, it is possible to suppress the occurrence of ink accumulation on the ink ejection surface.

1 is a diagram illustrating a configuration of an ink jet recording apparatus according to an embodiment of the present invention. It is a perspective view which shows the head part of the inkjet recording device shown in FIG. It is a figure which shows the functional structure of the control part of the inkjet recording device shown in FIG. 1, a recording head, and a wiper part. It is a side view which shows the recording head of the inkjet recording device shown in FIG. It is a figure which shows the state which the moving mechanism shown in FIG. 3 lowered | hung the wiper. It is a figure which shows the state which the movement mechanism shown in FIG. 3 raised the wiper. (A)-(e) is a figure which respectively shows the operation | movement (outward path) of the wiper shown in FIG. (A)-(e) is a figure which respectively shows the operation | movement (return way) of the wiper shown in FIG. FIG. 9D is a cross-sectional view comparing the ink reservoirs of FIG. 7D and FIG. It is a flowchart (first half part) which shows operation | movement of the control part shown in FIG. It is a flowchart (second half part) which shows operation | movement of the control part shown in FIG.

  Hereinafter, an inkjet recording apparatus 1 and a wiping method according to an embodiment of the present invention will be described with reference to the drawings (FIGS. 1 to 11). However, the present invention is not limited to the following embodiments. In addition, in order to avoid redundancy, the same or corresponding parts in the drawings will be denoted by the same reference numerals, and description thereof will not be repeated. In the present embodiment, the X axis and the Y axis shown in the figure are parallel to the horizontal plane, and the Z axis is parallel to the vertical line.

  First, an ink jet recording apparatus 1 according to this embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 shows the configuration of the inkjet recording apparatus 1. The ink jet recording apparatus 1 includes a tray 200, a feeding roller 201, a first transport unit 205, a head unit 3, a control unit 50, a wiper unit 60, a second transport unit 212, a discharge roller pair 216, and a cap unit 290. .

  The tray 200 stores the recording medium P, and is provided on the upstream side (right side in FIG. 1) of the recording medium P in the transport direction D0 with respect to the first transport unit 205. A feeding roller 201 is provided at the downstream end (the left end in FIG. 1) of the tray 200 in the transport direction D0. The feeding roller 201 supplies the recording medium P stored in the tray 200 to the first transport unit 205 one by one. The recording medium P is a medium on which an image is formed by the recording head 10, and is, for example, plain paper, copy paper, recycled paper, thin paper, thick paper, glossy paper, and OHP (Overhead Projector). A sheet made of a synthetic resin such as a sheet is included.

  The first transport unit 205 includes a first drive roller 206, a first driven roller 207, and a first transport belt 208. The first transport belt 208 is stretched around the first drive roller 206 and the first driven roller 207. When the first driving roller 206 is driven to rotate counterclockwise by a motor (not shown), the first conveying belt 208 rotates, and the recording medium P placed on the first conveying belt 208 moves in the conveying direction D0 ( It is conveyed in the left direction in FIG.

  The head unit 3 is disposed to face the upper surface of the upper belt in the first transport belt 208. The head unit 3 includes a head housing 18 and line heads 10Y, 10M, 10C, and 10K. The head housing 18 holds the line heads 10Y, 10M, 10C, and 10K. The line heads 10Y, 10M, 10C, and 10K eject yellow ink, magenta ink, cyan ink, and black ink, respectively. The line heads 10Y to 10K are arranged along the conveyance direction D0 of the recording medium P.

  As shown in FIG. 1, the second transport unit 212 is disposed downstream of the first transport unit 205 in the transport direction D <b> 0 (left side in FIG. 1). The second transport unit 212 includes a second drive roller 213, a second driven roller 214, and a second transport belt 215. The second transport belt 215 is stretched around the second drive roller 213 and the second driven roller 214. When the second drive roller 213 is driven to rotate counterclockwise by a motor (not shown), the second transport belt 215 rotates, and the recording medium P placed on the second transport belt 215 moves in the transport direction D0 ( It is conveyed in the left direction in FIG.

  The recording medium P on which an image is formed by the head unit 3 is sent to the second transport unit 212, and the ink attached to the surface of the recording medium P is dried while the recording medium P passes through the second transport unit 212. The A wiper unit 60 and a cap unit 290 are located below the second transport unit 212.

  The control unit 50 controls the overall operation of the inkjet recording apparatus 1. For example, the control unit 50 lowers the first transport unit 205 before causing the wiper unit 60 to wipe off ink adhering to the ink ejection surfaces 17 of the line heads 10Y to 10K, that is, before performing wiping. Then, the control unit 50 horizontally moves the wiper unit 60 disposed below the second transport unit 212 and is positioned below the head unit 3 which is a standby position. As a result, the wiper unit 60 is disposed between the head unit 3 and the first transport unit 205. As will be described later with reference to FIGS. 3 to 11, the wiper unit 60 wipes off the ink adhering to the line heads 10 </ b> Y to 10 </ b> K and collects the wiped ink.

  For example, the control unit 50 moves the cap unit 290 horizontally and positions it below the head unit 3 before capping the ink ejection surfaces 17 (see FIG. 3) of the line heads 10Y to 10K. Further, the control unit 50 moves the cap unit 290 upward. As a result, the cap unit 290 is attached to the ink ejection surface 17 of the line heads 10Y to 10K. The details of the control unit 50 will be described later with reference to FIG.

  The discharge roller pair 216 is disposed on the downstream side (left side in FIG. 1) in the transport direction D0 with respect to the second transport unit 212, and discharges the recording medium P on which an image has been formed to the outside of the inkjet recording apparatus 1.

  FIG. 2 is a perspective view showing the head unit 3 of the inkjet recording apparatus 1 shown in FIG. As shown in FIG. 2, each of the line heads 10Y to 10K includes three recording heads 10 arranged in a staggered manner along a direction (here, the X-axis direction) perpendicular to the transport direction D0.

  Next, the recording head 10, the wiper unit 60, and the control unit 50 will be described with reference to FIG. FIG. 3 is a diagram illustrating a functional configuration of the control unit 50 of the inkjet recording apparatus 1 illustrated in FIG. 1, the recording head 10, and the wiper unit 60. The wiper unit 60 includes the wiper 20 and the moving mechanism 30. The wiper 20 is attached to the moving mechanism 30 at a predetermined angle θ (here, 30 degrees) in the XZ plane so that the upper end portion is located on the right side (the negative direction of the X axis) from the lower end portion. ing.

  The recording head 10 has an ink ejection surface 17 on its lower surface. A large number of nozzles 11 are open at the center of the ink ejection surface 17. The nozzle 11 ejects ink for forming an image on the recording medium P (see FIG. 1). The nozzle 11 discharges the ink Nf together with the unnecessary matter in the recording head 10 in the purge process. The ink Nf is accommodated in a sealed space (an ink tank not shown). Therefore, evaporation of the volatile component contained in the ink Nf is prevented. Volatile components contained in the ink Nf evaporate when exposed to the outside air. As a result, the ink Nf discharged from the nozzles 11 has a lower viscosity than the residual ink Nv (see FIGS. 7C to 7E) that has been in contact with air.

  The control unit 50 moves the wiper 20 via the moving mechanism 30. The moving mechanism 30 moves the wiper 20 in accordance with an instruction from the control unit 50. Specifically, the moving mechanism 30 can move the wiper 20 in the ascending direction D1, can move the wiper 20 in the wiping direction D3 or the wiping direction D4, and moves the wiper 20 in the descending direction D2. Can do. In the present embodiment, the ascending direction D <b> 1 and the descending direction D <b> 2 are along the Z axis and are orthogonal to the ink ejection surface 17. Further, the wiping direction D3 and the wiping direction D4 are along the X axis and the ink ejection surface 17. The ascending direction D1 and the descending direction D2 may be collectively referred to as the vertical direction.

  The moving mechanism 30 moves the wiper 20 in the ascending direction D1, the descending direction D2, the wiping direction D3, and the wiping direction D4 according to an instruction from the control unit 50. For example, when wiping the ink discharge surface 17 with the wiper 20, the moving mechanism 30 moves the wiper 20 along the ink discharge surface 17 while pressing the wiper 20 against the ink discharge surface 17. As a result, the wiper 20 can wipe the ink Nf discharged from the nozzle 11 or the ink Nv discharged from the nozzle 11 and attached to the ink discharge surface 17. In addition, the wiper 20 wipes off unnecessary objects (for example, dust and dirt) adhering to the ink ejection surface 17.

  The wiper 20 has elasticity and is formed in a flat plate shape. The wiper 20 is made of, for example, a synthetic rubber containing EPDM (ethylene-propylene-diene terpolymer) or a synthetic resin. Moreover, the front-end | tip (upper end) of the wiper 20 is flat (flat) in this embodiment. The structure of the moving mechanism 30 will be described later with reference to FIGS.

  A plate-like member 40 that is bent in an L shape is disposed on the lower surface of one end portion (left end portion in FIG. 3) of the recording head 10. The plate member 40 includes a hydrophilic portion 41 and a water repellent portion 42. The hydrophilic portion 41 has higher hydrophilicity than the ink discharge surface 17. The hydrophilic portion 41 is formed of, for example, a highly hydrophilic metal such as stainless steel or a highly hydrophilic synthetic resin. The surface roughness of the hydrophilic portion 41 is rougher than the surface roughness of the ink ejection surface 17. Here, it is sufficient that the hydrophilic portion 41 has higher hydrophilicity than the ink discharge surface 17. Therefore, for example, the hydrophilic portion 41 is formed of a metal or a synthetic resin, and the surface roughness of the hydrophilic portion 41 is made larger than the surface roughness of the ink discharge surface 17, whereby the hydrophilicity of the hydrophilic portion 41 is made to be the ink discharge surface 17. Higher than the hydrophilicity.

  The water repellent part 42 has higher water repellency than the ink ejection surface 17 and the hydrophilic part 41. The water repellent part 42 is made of, for example, a fluororesin. The water repellent part 42 is disposed outside the hydrophilic part 41 with respect to the ink ejection surface 17 (on the left side in FIG. 3). The hydrophilic part 41 and the water repellent part 42 are configured adjacent to each other. The water repellent part 42 is disposed to be inclined obliquely upward (upper left in FIG. 3) with respect to the ink ejection surface 17.

  Next, a functional configuration of the control unit 50 will be described. The controller 50 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The ROM stores a control program for executing the wiping method according to the present invention. The CPU functions as various functional units including the first movement instruction unit 51 and the second movement instruction unit 52 by reading and executing the control program stored in the ROM. The RAM is used as a work area when the CPU executes the control program.

  The first movement instruction unit 51 moves the wiper 20 in the wiping direction D3 along the ink ejection surface 17 via the movement mechanism 30, and causes the ink Nf to move to one end (for example, the left end) of the recording head 10. Accumulate on. Further, the first movement instruction unit 51 spreads the ink uniformly in the width direction (direction perpendicular to the paper surface of FIG. 3: Y-axis direction) by pressing the wiper 20 in the vicinity of the accumulated ink.

  The second movement instruction unit 52 moves the wiper 20 in the wiping direction D4 along the ink ejection surface 17 via the movement mechanism 30, and performs wet wiping of the ink ejection surface 17 using the stored ink Nf. Do. The details of the operations of the first movement instruction unit 51 and the second movement instruction unit 52 will be described later with reference to FIGS.

  Here, the recording head 10 will be described with reference to FIG. FIG. 4 is a side view showing the recording head 10 of the inkjet recording apparatus 1 shown in FIG. The recording head 10 has an inlet 13 and an outlet 15. The inflow port 13 is an opening through which the ink Nf shown in FIG. 3 flows. The outlet 15 is an opening through which the ink Nf flows out. In other words, during the image forming process or the purge process, the ink Nf that has flowed into the inlet 13 from an ink tank (not shown) flows into the recording head 10 and flows out from the outlet 15. The ink Nf that has flowed into the recording head 10 is ejected from the nozzle 11 during the image forming process, and is discharged from the nozzle 11 during the purge process. In the present embodiment, the wiper 20 performs wet wiping using the ink Nf discharged from the nozzle 11 during the purge process and attached to the ink ejection surface 17.

  Next, the moving mechanism 30 will be described with reference to FIGS. 5 and 6. FIG. 5 is a view showing a state where the moving mechanism 30 shown in FIG. 3 lowers the wiper 20. FIG. 6 is a diagram illustrating a state where the moving mechanism 30 illustrated in FIG. 3 raises the wiper 20. 5 and 6, the plate-like member 40, the hydrophilic portion 41, and the water repellent portion 42 are omitted for simplification of the drawing. The control unit 50 moves the wiper unit 60 to face the line heads 10Y, 10M, 10C, and 10K before executing wiping. In FIG. 5, only three wipers 20 corresponding to the three recording heads 10 included in the line head 10K are shown for convenience.

  As shown in FIGS. 5 and 6, the moving mechanism 30 includes a carriage 31, a support frame 35 that supports the carriage 31, a roller 36, a gap roller 37, a lifting member 38, and a bottom 39. The elevating members 38 each include a lift member 38a and a shaft 38b.

  The bottom 39 supports the support frame 35 via the elevating member 38. The elevating member 38 is disposed on the bottom 39 and supports the support frame 35 to move up and down. The shaft 38b is rotationally driven by a motor (not shown), and moves up and down the support frame 35 via the lift member 38a. The lift member 38a is configured integrally with the shaft 38b, and rotates integrally with the shaft 38b when the shaft 38b is driven to rotate. Further, the support frame 35 is moved up and down as the lift member 38a rotates. More specifically, the shaft 38b of the elevating member 38 is rotationally driven by a motor (not shown), and the lift member 38a is raised, whereby the lift member 38a of the elevating member 38 raises the support frame 35. Further, the shaft 38b of the elevating member 38 is rotationally driven by a motor (not shown), and the lift member 38a falls down, so that the lift member 38a of the elevating member 38 lowers the support frame 35.

  The support frame 35 is supported by an elevating member 38 and supports the carriage 31 through the roller 36 so as to be movable in the X-axis direction (wiping direction D3 and wiping direction D4). The roller 36 is supported by the support frame 35, and moves on the support frame 35 to move the carriage 31 in the X-axis direction (wiping direction D3 and wiping direction D4).

  The carriage 31 is supported by the support frame 35 via the roller 36 and moves in the X-axis direction (wiping direction D3 and wiping direction D4). The carriage 31 is provided with a gap roller 37 and a wiper 20. The gap roller 37 is in contact with the head housing 18 when the support frame 35 is lifted by the elevating member 38, so that the vertical position (upper limit position) of the wiper 20 pressed against the ink discharge surface 17 is constant. Hold on. The wiper 20 is attached to the carriage 31 at a predetermined angle θ (here, 30 degrees) in the XZ plane so that the upper end portion is located on the right side (the negative direction of the X axis) from the lower end portion. Yes.

  Here, the operation of the moving mechanism 30 when the wiper 20 is raised will be described with reference to FIGS. 3, 5, and 6. First, the control unit 50 shown in FIG. 3 drives a motor (not shown) to rotate the shaft 38b of the elevating member 38 arranged on the upstream side (right side in FIG. 5) in the wiping direction D3 in the clockwise direction. The shaft 38b of the elevating member 38 disposed on the downstream side in the direction D3 (left side in FIG. 5) is rotated counterclockwise. Then, the lying lift member 38a is changed to the standing state. As a result, as shown in FIG. 6, the carriage 31, the roller 36, the gap roller 37, and the wiper 20 rise together with the support frame 35.

  As shown in FIG. 6, the gap roller 37 abuts against the head housing 18, and as a result, the position of the wiper 20 that is lifted and pressed against the ink ejection surface 17 is held constant. The carriage 31 is supported by a support frame 35 through a roller 36 so as to be movable. As the carriage 31 moves in the wiping direction D3 or wiping direction D4, the wiper 20 also moves in the wiping direction D3 or wiping direction D4.

  The three wipers 20 corresponding to each of the line heads 10Y, 10M, and 10C are operated by the moving mechanism 30 in the same manner as the three wipers 20 corresponding to the line head 10K.

  Next, the operation of the wiper 20 will be described with reference to FIGS. FIG. 7A to FIG. 7E are diagrams showing the operation (outward path) of the wiper 20 shown in FIG. The wiper 20 operates as described below when the moving mechanism 30 operates in accordance with instructions from the control unit 50 (the first movement instruction unit 51 and the second movement instruction unit 52). The wiper 20 is inclined at a predetermined angle θ (here, 30 degrees) in the XZ plane so that the upper end portion is located on the right side (the negative direction of the X axis) from the lower end portion.

  In the initial state, since the nozzle 11 discharges the ink Nf, the ink Nf remains in the ink adhesion area FA. The wiper 20 is at the lower limit position. As shown in FIG. 7A, the wiper 20 is located outside the ink adhering area FA and is at the first contact position at one end of the recording head 10 (the right end in FIG. 7A). It is moved to a position immediately below PT1 and moves (rises) in the rising direction D1. Then, the tip of the wiper 20 is pressed against the ink ejection surface 17, and the wiper 20 stops rising. When the tip of the wiper 20 is pressed against the ink discharge surface 17, the ink Nv attached to the tip of the wiper 20 adheres to the ink discharge surface 17, as shown in FIG.

  Next, as shown in FIG. 7B, the wiper 20 maintains the vertical position at a constant level (still at the upper limit position), and the wiping direction D3 from the first contact position PT1 toward the hydrophilic portion 41. To stop at the first stop position PS1 in the hydrophilic portion 41. Thereafter, as shown in FIG. 7C, the wiper 20 moves a predetermined distance LB (6 mm in this case) in the wiping direction D4 while keeping the position in the vertical direction constant (still at the upper limit position), and becomes hydrophilic. It stops at the stop position PS1a in the section 41. Then, as shown in FIG. 7D, the wiper 20 moves (lowers) in the downward direction D2. As a result, the ink Nf remaining in the ink adhesion area FA is wiped off by the wiper 20, and the ink Nf is stored in the vicinity of the first stop position PS1 in the hydrophilic portion 41.

  Then, as shown in FIG. 7D, the wiper 20 is wiped directly below the first stop position PS1 at the left end of the recording head 10 while keeping the position in the vertical direction constant (still at the lower limit position). It is moved in the direction D3 and moved (raised) in the rising direction D1 at the first stop position PS1. Then, as shown in FIG. 7E, the tip of the wiper 20 is pressed against the ink discharge surface 17, and the wiper 20 stops rising. Thereafter, the wiper 20 moves (lowers) in the downward direction D2.

  As described above, since the wiper 20 is pressed against the first stop position PS1 in the vicinity of the position where the ink Nf is stored, the stored ink Nf is in the width direction (direction perpendicular to the paper surface of FIG. 7: Y axis). Direction).

  FIG. 9 is a cross-sectional view comparing the ink reservoirs of FIG. 7 (d) and FIG. 8 (a). 9A is a diagram (AA sectional view) showing the ink reservoir of FIG. 7D, and FIG. 9B is a diagram showing the ink reservoir of FIG. 8A (BB). FIG. As shown in FIG. 9A, the height of the ink reservoir in FIG. 7D is higher as the distance from the center in the width direction is shorter. When the “second wiping step” shown in FIGS. 8A to 8E is performed in this state, no wiping residue is generated because the wet wiping is performed at the central portion in the width direction, but fresh at the end in the width direction. Ink Nf may be insufficient and unwiping may occur. On the other hand, as shown in FIG. 9B, the height of the ink reservoir in FIG. 8A is substantially uniform. Therefore, since the wet wiping is performed at the end in the width direction similarly to the central portion in the width direction, no wiping residue is generated.

  Further, since the wiper 20 descends after a predetermined distance LB (here, 6 mm) from the first stop position PS1, the amount of ink Nf adhering to the wiper 20 can be reduced. As a result, a large amount of fresh ink Nf can be stored near the first stop position PS1 in the hydrophilic portion 41. Here, the fresh ink Nf is ink immediately after being ejected from the nozzle 11 and is an ink in which volatile components contained in the ink are hardly evaporated. On the other hand, the residual ink Nv is an ink that has passed for a predetermined time (for example, 3 minutes) or more after being discharged from the nozzle 11 and has an increased viscosity due to evaporation of volatile components contained in the ink.

  Further, since the predetermined distance LB that is the back distance is 3 mm or more and 10 mm or less, the fresh ink Nf wiped by the wiper 20 can be effectively separated from the wiper 20. Since the fresh ink Nf can be effectively separated from the wiper 20, the amount of ink Nf adhering to the wiper 20 can be reduced. Accordingly, a large amount of fresh ink Nf can be stored near the first stop position PS1.

  Furthermore, since the wiper 20 is disposed at a predetermined angle θ (here, 30 degrees) from the plane perpendicular to the ink ejection surface 17 (YZ plane), the wiper 20 is moved when the wiper 20 backs up. It is possible to avoid the tip of the buckling.

  Further, since the predetermined angle θ is not less than 5 degrees and not more than 45 degrees (here, 30 degrees), it is possible to more reliably avoid the tip of the wiper 20 from buckling when the wiper 20 is backing. Can do.

  Furthermore, since the first stop position PS1 is a position included in the hydrophilic portion 41, a larger amount of ink Nf can be stored in the vicinity of the first stop position PS1.

  FIGS. 8A to 8E are diagrams showing the operation (return path) of the wiper 20 shown in FIG. As shown in FIG. 8 (a), after the wiper 20 descends at the first stop position PS1, the position in the vertical direction is maintained constant (still at the lower limit position), and the wiper 20 is moved to the second contact position PT2. It is moved in the wiping direction D3 to just below. Ink Nf adheres to the tip of the wiper 20. Next, as shown in FIG. 8B, the wiper 20 moves (rises) toward the water repellent part 42 in the rising direction D <b> 1 and is water repellent at the second contact position PT <b> 2 in the water repellent part 42. It abuts against the portion 42 and stops rising at the upper limit position.

  Next, as shown in FIG. 8C, the wiper 20 moves in the wiping direction D4 via the hydrophilic portion 41 while keeping the position in the vertical direction constant (still at the upper limit position). The ink Nf adhering to 41 is wiped off.

  Next, as shown in FIG. 8D, the wiper 20 is wiped to the second stop position PS2, which is a position near the right end of the recording head 10, while maintaining the position in the vertical direction constant (still at the upper limit position). Move in direction D4.

  Next, as shown in FIG. 8E, after the wiper 20 that has reached the second stop position PS2 stops, it moves (lowers) in the downward direction D2. Then, the wiper 20 returns to the standby position and finishes wiping.

  As described above with reference to FIGS. 7 and 8, a large amount of fresh ink Nf is provided in the vicinity of the first stop position PS1, and the width direction (direction perpendicular to the paper surface of FIGS. 7 and 8: Y-axis direction). ) Can be uniformly stored. Further, by using this fresh ink Nf and performing wet wiping from the second contact position PT2 to the second stop position PS2, the ink attached to the ink ejection surface 17 of the recording head 10 can be wiped off with a simple configuration. Therefore, it is possible to suppress the occurrence of ink accumulation on the ink ejection surface 17.

  Furthermore, since the second contact position PT2 is a position included in the water repellent portion 42, the ink Nf attached to the tip of the wiper 20 can be prevented from attaching to the vicinity of the second contact position PT2.

  Further, the water repellent part 42 is formed to be inclined obliquely upward. Therefore, when the wiper 20 moves from the water repellent part 42 to the hydrophilic part 41, the wiper 20 can enter the hydrophilic part 41 while gradually curving the tip of the wiper 20 according to the inclination of the water repellent part 42. As a result, damage to the tip of the wiper 20 can be reduced as compared with the case where the wiper 20 is raised in the upward direction D1 toward the hydrophilic portion 41 and pressed against the hydrophilic portion 41.

  Next, the operation of the control unit 50 will be described with reference to FIGS. 10 and 11. FIG. 10 is a flowchart (first half) showing the operation of the control unit 50 shown in FIG. FIG. 11 is a flowchart (second half) showing the operation of the control unit 50 shown in FIG. First, as shown in FIG. 7A, the wiper 20 is moved below the first contact position PT1 in accordance with an instruction from the first movement instruction unit 51 shown in FIG. 3 (step S101). Next, according to an instruction from the first movement instruction unit 51, the wiper 20 is moved in the upward direction D1 and pressed against the ink ejection surface 17 as shown in FIG. 7B (step S103).

  Then, according to an instruction from the first movement instruction unit 51, the wiper 20 is moved in the left direction (wiping direction D3) while wiping the ink discharge surface 17 as shown in FIG. 7B (step S105). . Next, as shown in FIG. 7C, the wiper 20 is stopped at the first stop position PS1 by an instruction from the first movement instruction unit 51 (step S107). Then, according to an instruction from the first movement instructing unit 51, as shown in FIG. 7D, the wiper 20 moves to the right (wiping direction D4) from the first stop position PS1 by a predetermined distance LB (here, 6 mm). (Step S109). Next, according to an instruction from the first movement instruction unit 51, the wiper 20 is moved (lowered) in the descending direction D2 and separated from the ink ejection surface 17 (step S111). Then, in accordance with an instruction from the first movement instruction unit 51, the wiper 20 is moved in the left direction (wiping direction D3) to a position immediately below the first stop position PS1 (step S113). Next, according to an instruction from the first movement instruction unit 51, the wiper 20 is moved in the upward direction D1 and pressed against the first contact position PT1 of the ink ejection surface 17 (step S115). Then, as shown in FIG. 7E, the wiper 20 is moved (lowered) in the descending direction D2 by the instruction from the first movement instructing unit 51 and separated from the ink ejection surface 17 (step S117).

  Next, as shown in FIG. 8A, the wiper 20 is moved directly below the second contact position PT2 by an instruction from the second movement instruction unit 52 (step S119). Then, according to an instruction from the second movement instruction unit 52, the wiper 20 is moved (raised) in the ascending direction D1, as shown in FIG. 8B, and the water repellent part, as shown in FIG. 8C. The second abutment position PT2 in the abutment 42 abuts on the water repellent part 42, and the rise is stopped at the upper limit position (step S121). Subsequently, according to an instruction from the second movement instruction unit 52, the wiper 20 is moved in the wiping direction D4 while wiping the ink discharge surface 17 (step S123).

  Next, as shown in FIG. 8D, the wiper 20 is stopped at the second stop position PS2 by an instruction from the second movement instruction unit 52 (step S125). Then, the wiper 20 is moved (lowered) in the descending direction D2 by an instruction from the second movement instructing unit 52, and is separated from the ink ejection surface 17 (step S127) as shown in FIG. 8E. Ends.

  In the flowcharts shown in FIGS. 10 and 11, Steps S101 to S107 correspond to an example of “first wiping process”, and Steps S109 to S117 correspond to an example of “ink equalization process”, and Step S119. To Step S127 corresponds to an example of a “second wiping step”.

  As described above, since the wet wiping from the second contact position PT2 to the second stop position PS2 is performed using the fresh ink Nf stored in the vicinity of the first stop position PS1 and made uniform in the width direction, it is simple. With the configuration, the inks Nf and Nv adhering to the ink ejection surface 17 of the recording head 10 can be wiped off. Therefore, it is possible to suppress the occurrence of ink accumulation on the ink ejection surface 17.

  The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the gist thereof (for example, (1) to (9) shown below). In order to facilitate understanding, the drawings schematically show each component mainly, and the thickness, length, number, etc. of each component shown in the drawings are different from the actual for convenience of drawing. There is a case. Moreover, the shape, dimension, etc. of each component shown by said embodiment are an example, Comprising: It does not specifically limit, A various change is possible in the range which does not deviate substantially from the structure of this invention.

  (1) As described with reference to FIG. 7, in the present embodiment, in the “ink equalization step”, after the wiper 20 stops at the first stop position PS <b> 1, the wiper 20 backs by a predetermined distance LB and discharges ink. Although the case where the ink is separated from the surface 17, pressed against the first stop position PS <b> 1 again, and separated from the ink ejection surface 17 has been described, the “ink equalization step” may be in other forms. For example, the wiper 20 may be stopped at the first stop position PS <b> 1, separated from the ink ejection surface 17, pressed against the first stop position PS <b> 1 again, and separated from the ink ejection surface 17 again. In this case, the process is simplified.

  (2) As described with reference to FIG. 7, the case where the predetermined distance LB that is the back distance is 3 mm or more and 10 mm or less (here, 6 mm) has been described. May be 3 mm or more. The longer the predetermined distance LB, the more reliably the wiper 20 can be separated from the ink Nf. However, an appropriate range of the predetermined distance LB varies depending on the material and size of the wiper 20.

  (3) As described with reference to FIG. 7, in the present embodiment, the wiper 20 is disposed with an inclination of a predetermined angle θ from a plane (XZ plane) perpendicular to the ink ejection surface 17. Although demonstrated, the form where the wiper 20 is not inclined may be used.

  (4) As described with reference to FIG. 7, in the present embodiment, the case where the predetermined angle θ is 5 degrees or more and 45 degrees or less (for example, 30 degrees) has been described. The angle θ may be 5 degrees or more. As the predetermined angle θ is larger, it is possible to more reliably avoid the tip of the wiper 20 from buckling when the wiper 20 is backing. However, the appropriate range of the predetermined angle θ varies depending on the material and size of the wiper 20.

  (5) As described with reference to FIG. 7, in the present embodiment, the case where the first stop position PS <b> 1 is a position within the hydrophilic portion 41 has been described. The position in the ink discharge surface 17 at the left end) may be used.

  (6) As described with reference to FIG. 8, in the present embodiment, the case where the second contact position PT2 is a position in the water repellent portion 42 has been described. However, the second contact position PT2 is the recording head. It may be a position in the ink discharge surface 17 at one end portion (for example, the left end portion) of 10.

  (7) As described with reference to FIG. 8, in the present embodiment, the second stop position PS <b> 2 is near the end of the ink ejection surface 17 at the other end (for example, the right end) of the recording head 10. Although the case of the position has been described, the position may be a position outside the recording head 10 with respect to the first contact position PT1. However, the second stop position PS2 is preferably close to the end of the ink ejection surface 17 at the other end (for example, the right end) of the recording head 10. The closer the second stop position PS2 is to the end of the ink discharge surface 17, the less the amount of ink Nf adhering to the ink discharge surface 17 and the upper end of the wiper 20 after the wiper 20 is separated from the ink discharge surface 17. Can do.

  (8) As described with reference to FIG. 7, in the present embodiment, a plate-like shape having the hydrophilic portion 41 and the water repellent portion 42 at one end portion (left end portion in FIG. 3) of the recording head 10. Although the case where the member 40 is arrange | positioned was demonstrated, another form may be sufficient. For example, the plate-like member 40 may be disposed at both ends of the recording head 10, or the plate-like member 40 may not be disposed on the recording head 10. When the plate-like members 40 are disposed at both ends of the recording head 10, respectively, the second stop position PS2 is set to a position within the water-repellent portion 42 of the plate-like member 40 disposed at the right end. In addition, the amount of ink Nf adhering to the ink ejection surface 17 and the upper surface of the wiper 20 can be further reduced.

  (9) As described with reference to FIG. 7, in the present embodiment, the case where the tip (upper end) of the wiper 20 is flat (flat) has been described, but the tip of the wiper 20 is inclined and processed. It may be a form. In this case, the amount of ink Nf adhering to the ink discharge surface 17 and the tip of the wiper 20 can be further reduced.

  The present invention can be used in the field of an ink jet recording apparatus provided with a recording head for discharging ink onto a recording medium. The present invention can also be used in the field of wiping methods for wiping ink adhering to the ink ejection surface of a recording head with a wiper.

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 10 Recording head 11 Nozzle 17 Ink discharge surface 20 Wiper 30 Movement mechanism 40 Plate member 41 Hydrophilic part 42 Water repellent part 50 Control part 51 1st movement instruction part 52 2nd movement instruction part D1 Ascending direction D2 Descent direction D3 Wiping direction (Left)
D4 Wiping direction (right direction)
FA ink adhesion area LB predetermined distance Nv ink Nf ink PS1 first stop position PT1 first contact position PS2 second stop position PT2 second contact position

Claims (8)

A recording head for discharging ink onto the recording medium;
A wiper for wiping off ink adhering to the ink ejection surface of the recording head;
A moving mechanism for moving the wiper;
An ink jet recording apparatus comprising: a control unit that controls the operation of the wiper via the moving mechanism;
The control unit includes a first movement instruction unit that moves the wiper via the movement mechanism, and a second movement instruction unit,
The first movement instruction unit includes:
The wiper is pressed against the ink ejection surface at a first contact position at one end of the recording head outside an ink adhesion area, which is an area where ink ejected from nozzles is adhered, A first wiping operation for moving to the first stop position at the other end of the recording head along the ink ejection surface via an ink adhesion region;
After the first wiping operation, the ink wiper is moved away from the ink discharge surface, pressed against the ink discharge surface again at the first stop position, and separated from the ink discharge surface again. Done
After the ink equalization operation, the second movement instruction unit pushes the wiper against the ink ejection surface at a second contact position outside the first stop position at the other end of the recording head. After the contact is moved toward the one end of the recording head along the ink ejection surface, the recording head is stopped at a second stop position outside the recording head from the first contact position. An ink jet recording apparatus that performs a second wiping operation for separating from an ink ejection surface.   The first movement instructing unit moves the wiper to the first stop position, moves the wiper a predetermined distance toward the one end of the recording head, and stops the ink in the ink uniform operation. 2. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is separated from the ink ejection surface, is pressed against the ink ejection surface again at the first stop position, and is separated from the ink ejection surface again.   The inkjet recording apparatus according to claim 2, wherein the predetermined distance is 3 mm or more and 10 mm or less.   4. The inkjet recording apparatus according to claim 1, wherein the wiper is disposed at a predetermined angle with respect to a plane perpendicular to the ink ejection surface. 5.   The inkjet recording apparatus according to claim 4, wherein the predetermined angle is not less than 5 degrees and not more than 45 degrees. A hydrophilic portion whose surface is more hydrophilic than other regions of the ink discharge surface is formed on the ink discharge surface at the other end portion of the recording head.
The inkjet recording apparatus according to any one of claims 1 to 5, wherein the first stop position is a position included in the hydrophilic portion. A water-repellent portion having a surface that is more water-repellent than other regions of the ink-discharging surface is formed on the ink-discharging surface outside the other end portion of the recording head.
The ink jet recording apparatus according to claim 1, wherein the second contact position is a position included in the water repellent portion. A wiping method for wiping off ink adhering to an ink ejection surface of a recording head with a wiper,
A control unit that controls the operation of the wiper, a first wiping step of moving the wiper via a moving mechanism that moves the wiper, an ink equalization step,
And including a second wiping step,
In the first wiping step, the ink wiper is placed outside the ink adhesion area, which is an area where the ink ejected from the nozzles is adhered, at a first contact position at one end of the recording head. Press against the ejection surface, and move to the first stop position at the other end of the recording head along the ink ejection surface via the ink adhesion region;
After the first wiping step, in the ink equalization step, the wiper is separated from the ink discharge surface, pressed against the ink discharge surface again at the first stop position, and separated from the ink discharge surface again. ,
After the ink equalization step, in the second wiping step, the wiper is pushed against the ink ejection surface at a second contact position outside the first stop position at the other side end of the recording head. After the contact is moved toward the one end of the recording head along the ink ejection surface, the recording head is stopped at a second stop position outside the recording head from the first contact position. A wiping method for separating from the ink ejection surface.

Images