JP2013049205A - Wiping mechanism and inkjet recording apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiping mechanism that prevents damage and breakage of a wiper and can control generation of accumulated ink at an upstream side more than a wiping start position, and to provide an inkjet recording apparatus including the same.SOLUTION: The wiping mechanism 30 has a first wiper 33 and a second wiper 34. The first wiper 33 is in pressure contact with a wiping start position S outside of a nozzle region R from a nearly vertical direction, and wipes off an ink ejection surface 13a including a nozzle region R in a predetermined direction. The second wiper 34 is arranged at the upstream side of the first wiper 33 relative to the wiping direction of the ink ejection surface 13a, and is separated from the ink ejection surface 13a at the upstream side of the nozzle region R, after the accumulated ink 22a formed with the ink adhered to the tip of a first wiper 33 at wiping operation since the second times is moved to the wiping direction downstream side.

Description

  The present invention relates to an ink jet recording apparatus that performs recording by ejecting ink onto a recording medium such as paper, and more particularly to a wiping mechanism that cleans an ink ejection surface of a recording head.

  Recording devices such as facsimiles, copiers, and printers are configured to record an image on a recording medium such as paper or an OHP sheet. Depending on the recording method, ink jet, wire dot, thermal, etc. Can be classified. The ink jet recording method can be classified into a serial type in which recording is performed while the recording head scans a recording medium, and a line head type in which recording is performed by a recording head fixed to the apparatus main body.

  For example, in a line head type ink jet recording apparatus, each of the line heads having a recording area equal to or larger than the width of the recording medium while conveying the recording medium such as paper at high speed by a conveying means such as a conveying belt provided in the apparatus main body An image is formed on the recording medium by ejecting ink from the ink ejection nozzle. This enables high-speed printing as compared with a serial type ink jet head in which the recording head reciprocates in the width direction of the recording medium.

  In such an ink jet recording apparatus, in general, in order to prevent ink drying and nozzle clogging in an ink discharge nozzle provided with an opening on the ink discharge surface of a recording head, after discharging ink from the nozzle, The recording head is recovered by wiping off ink adhering to the ink ejection surface.

  For example, Patent Document 1 has at least two wipers that can sequentially come into contact with the ejection surface of a recording head, perform liquid application for the head and stir and mix with ink residues with the preceding wiper, and then with the subsequent wiper. An inkjet head cleaning device is disclosed which scrapes the mixture.

  Japanese Patent Application Laid-Open No. 2004-228867 discloses that the contact angle of the first wiper that first comes into sliding contact with the discharge surface of the recording head is smaller than the contact angle of the subsequent second wiper with respect to the discharge surface. There has been disclosed a wiping device capable of efficiently wiping ink leaking from the ejection surface of the head.

  By the way, in the methods of Patent Documents 1 and 2, when wiping the ink discharge surface of the recording head with a wiper, the wiper is disposed outside the ink discharge surface, and the wiper is moved from there to wipe the ink discharge surface. ing. However, in this configuration, the side surface of the wiper comes into contact with the corner of the recording head, and the wiper may be damaged or damaged.

  Therefore, Patent Documents 3 and 4 disclose a method of wiping the ink discharge surface by bringing a wiper into contact with a portion of the ink discharge surface of the recording head where there is no nozzle at a predetermined contact pressure. Specifically, as shown in FIG. 18A, the wiper 103 is placed substantially vertically on the ink ejection surface 101a of the recording head 101 outside the nozzle area 102 where the ink ejection nozzles are arranged (wiping start position). Press. Next, as shown in FIGS. 18B and 18C, the wiper 103 is horizontally moved in the direction of the arrow A along the ink discharge surface 101a to wipe off the ink 104 of the discharge nozzle portion 102, as shown in FIG. Thus, after the wiper 103 is separated from the ink discharge surface 101a, it is returned to the wiping start position by horizontally moving in the arrow A 'direction. According to this configuration, since the side surface of the wiper 103 does not contact the corner portion of the recording head 101, the wiper 103 can be prevented from being damaged or damaged.

JP 2006-205715 A JP 2006-312261 A JP 2002-283581 A JP 2009-56707 A

  However, in the method shown in FIG. 18, as shown in FIG. 19A, the inks 104a and 104b are attached to the side surface and the tip of the wiper 103 at the second wiping. The ink 104b adhering to the tip of the wiper 103 adheres to the upstream side of the wiper 103 with respect to the wiping direction (arrow A direction) due to the deflection of the wiper 103, as shown in FIG. Therefore, as shown in FIG. 19C, the ink 104a adhering to the side surface of the wiper 103 is wiped again, but the ink 104b adhering to the tip of the wiper 103 remains upstream from the wiping start position.

  By repeating the wiping operation as described above, the ink 104b gradually accumulates upstream from the wiping start position, resulting in a large ink reservoir. There is a problem in that this ink reservoir falls on or touches the recording medium passing below the ink discharge surface 101a, thereby contaminating the print surface.

  In view of the above-described problems, the present invention provides a wiping mechanism that can prevent the wiper from being damaged or damaged, and that can suppress the occurrence of ink accumulation upstream of the wiping start position, and an ink jet recording apparatus including the wiping mechanism. For the purpose.

  In order to achieve the above object, the present invention provides a recording head wiping mechanism for wiping the ink ejection surface of a recording head provided with a nozzle region in which an ejection nozzle for ejecting ink opens on a recording medium with a wiper, After being wiped in a predetermined direction by wiping the wiping start position outside the nozzle region in a substantially vertical direction, the ink discharge surface including the nozzle region is moved away from the ink discharge surface and moved in a direction opposite to the wiping direction, The first wiper that is pressed against the wiping start position again, and is pressed from the direction substantially perpendicular to the upstream side of the wiping start position with respect to the wiping direction, from the downstream side of the wiping start position to the upstream side of the nozzle region. Is wiped in the same direction as the first wiper, separated from the ink discharge surface, and again pressed against the upstream side of the wiping start position. It is characterized by having a second wiper, and.

  According to the present invention, in the wiping mechanism configured as described above, a reciprocating movement is possible along the ink discharge surface, and the first wiper is fixed to the first carriage, and the first carriage approaches the ink discharge surface. Alternatively, the second carriage is supported so as to be swingable in a separating direction and to which the second wiper is fixed, the urging member that urges the second carriage in a direction approaching the ink ejection surface, and the first carriage A support frame for reciprocally supporting one carriage; a guide rail fixed substantially parallel to the ink ejection surface; a drive mechanism for reciprocating the first carriage along the support frame; and the support frame. An elevating mechanism that elevates and lowers in the direction approaching or separating from the ink ejection surface together with the first carriage; By the second carriage with the movement of the come-up direction rides on the guide rail, and wherein the second wiper is separated from the ink ejection surface upstream of the nozzle region.

  According to the present invention, in the wiping mechanism configured as described above, the driving mechanism and the elevating mechanism simultaneously reciprocate and elevate the plurality of first carriages and second carriages provided corresponding to the plurality of recording heads. Accordingly, the ink discharge surfaces of the plurality of recording heads are simultaneously wiped by the first wiper and the second wiper.

  The present invention also provides an ink jet recording apparatus provided with the wiping mechanism having the above-described configuration.

  According to the first configuration of the present invention, the ink pool generated on the upstream side of the wiping start position on the ink discharge surface by the ink adhering to the tip of the first wiper is moved downstream of the wiping start position by the second wiper. As a result, even when the wiping operation is repeated, only an ink reservoir for one wiping operation is always generated. Further, since the second wiper is separated from the ink discharge surface on the upstream side of the nozzle region, excess ink does not adhere to the tip of the second wiper. For this reason, it is possible to effectively suppress the problem that the ink pool collects and drops as a large ink pool, or contacts the recording medium passing under the ink ejection surface and soils the recording medium. .

  According to the second configuration of the present invention, in the wiping mechanism of the first configuration, the second carriage rides on the guide rail as the first carriage to which the first wiper is fixed moves in the wiping direction. Thus, since the second wiper is separated from the ink ejection surface upstream of the nozzle region, there is no need to separately provide a drive source for separating the second wiper, and the same drive source as the reciprocating movement of the first wiper is used. Thus, the second wiper can be separated from the ink discharge surface with a simple configuration.

  According to the third configuration of the present invention, in the wiping mechanism of the second configuration, the plurality of first carriages and second carriages provided corresponding to the plurality of recording heads are simultaneously reciprocated and moved up and down. By simultaneously wiping the ink ejection surfaces of the plurality of recording heads with the first wiper and the second wiper, the maintenance time of each recording head can be shortened, and the drive control during maintenance can be simplified.

  Further, according to the fourth configuration of the present invention, by including the wiping mechanism having any one of the first to third configurations, the wiper can be wiped by wiping the wiper in pressure contact with the ink ejection surface from a substantially vertical direction. In addition, the ink jet recording apparatus can improve the durability of the recording medium and suppress the occurrence of ink accumulation on the upstream side of the wiping start position of the ink ejection surface, thereby effectively suppressing contamination of the recording medium.

1 is a side view schematically showing a schematic structure of an inkjet recording apparatus 100 according to an embodiment of the present invention. A plan view of the conveyance belt 5 of the inkjet recording apparatus 100 shown in FIG. Perspective view of line heads 11C, 11M, 11Y and 11K arranged above the conveyor belt 5 The perspective view of the recording head 13 which comprises each line head 11C-11K. The figure which shows typically the ink flow path from the ink tank 20 of the inkjet recording device 100 of this invention to the recording head 13. FIG. The perspective view which looked at the wiping mechanism 30 of this invention which wipes off the ink discharge surface 13a of the recording head 13 from diagonally upward. FIG. 4 is a perspective view of the wiping mechanism 30 as viewed obliquely from below, and shows a state where both the first wiper and the second wiper are pressed against the ink ejection surface. FIG. 4 is a perspective view of the wiping mechanism 30 as viewed obliquely from below, showing a state in which the second wiper is separated from the ink ejection surface. The front view which looked at the raising / lowering mechanism 50 which raises / lowers the wiping mechanism 30 from the paper discharge direction downstream side (left front side of FIG. 3). FIG. 6 is a diagram illustrating a wiping operation of the recording head 13 using the wiping mechanism 30 of the present invention, and a side view illustrating a state in which the first wiper 33 and the second wiper are pressed against the ink ejection surface during the first wiping operation. 10 is a side view showing a state in which the first wiper 33 and the second wiper 34 have moved in the wiping direction from the state of FIG. 10 and the wiping of the ink 22 by the first wiper 33 has started. 11 is a side view showing a state in which the first wiper 33 and the second wiper 34 have moved in the wiping direction from the state of FIG. 11 and the second wiper 34 has been separated from the ink ejection surface 13a. Side view showing a state in which the first wiping operation has been completed and the first wiper 33 has returned to the wiping start position S and the second wiper 34 has returned to the upstream side of the wiping start position S. The side view which shows the state in which the 1st wiper 33 and the 2nd wiper 34 were press-contacted to the ink discharge surface at the time of the 2nd wiping operation | movement. The first wiper 33 and the second wiper 34 move in the wiping direction from the state shown in FIG. 14, and the wiping of the ink 22 by the first wiper 33 is started and the ink reservoir 22a is moved by the second wiper 34. Side view 15 is a side view showing a state in which the first wiper 33 and the second wiper 34 have moved in the wiping direction from the state of FIG. 15 and the second wiper 34 has been separated from the ink ejection surface 13a. The side view which shows the state which the 2nd wiper returned to the upstream of the wiping start position S and the 2nd wiper 34 returned to the wiping start position S after the 2nd wiping operation | movement was complete | finished. Side view showing a conventional wiping mechanism that wipes the ink discharge surface of a recording head by bringing the wiper into contact with the ink discharge surface from a substantially vertical direction at a predetermined contact pressure. FIG. 18 is a side view showing a state where an ink pool is generated when the second wiping is performed using the conventional wiping mechanism shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view schematically showing a schematic configuration of an ink jet recording apparatus 100 having a wiping mechanism of the present invention, and FIG. 2 is a plan view of the conveyance belt 5 of the ink jet recording apparatus 100 shown in FIG. 3 is a perspective view of line heads 11C, 11M, 11Y, and 11K disposed above the conveyor belt 5, and FIG. 4 is a perspective view of the recording head 13 that constitutes each of the line heads 11C to 11K. 3 shows a state viewed from the back side of FIG. 1 (upper side of FIG. 2), and the arrangement of the line heads 11C to 11K is opposite to that of FIGS.

  As shown in FIG. 1, a paper feed tray 2 that accommodates paper P is provided on the left side of the ink jet recording apparatus 100, and the paper P accommodated at one end of the paper feed tray 2 is placed at the uppermost position. A sheet feeding roller 3 for conveying and feeding one sheet at a time to a conveying belt 5 to be described later, and a driven roller 4 that is in pressure contact with the sheet feeding roller 3 and driven to rotate are provided.

  A transport belt 5 is rotatably disposed on the downstream side (right side in FIG. 1) of the paper feed roller 3 and the driven roller 4 with respect to the paper transport direction (arrow X direction). The conveying belt 5 is stretched between a belt driving roller 6 disposed on the downstream side in the sheet conveying direction and a belt roller 7 disposed on the upstream side and rotated by the belt driving roller 6 via the conveying belt 5. As the belt driving roller 6 is driven to rotate in the clockwise direction, the paper P is conveyed in the direction of the arrow X.

  Here, since the belt driving roller 6 is arranged on the downstream side in the sheet conveying direction, the sheet feeding side (the upper side in FIG. 1) of the conveying belt 5 is pulled by the belt driving roller 6. The tension on the sheet feeding side can be increased, and the sheet P can be stably conveyed. In addition, a sheet made of dielectric resin is used for the transport belt 5, and a (seamless) belt mainly having no seam is used.

  Further, on the downstream side of the conveyance belt 5 with respect to the sheet conveyance direction, a discharge roller 8 that is driven clockwise in FIG. 1 and discharges the sheet P on which an image is recorded to the outside of the apparatus main body, A driven roller 9 that is pressed against the upper part and driven to rotate is provided, and a discharge tray 10 on which the paper P discharged out of the apparatus main body is stacked is provided on the downstream side of the discharge roller 8 and the driven roller 9. It has been.

  An image is recorded on the paper P that is supported above the conveyor belt 5 at a height such that a predetermined interval is formed with respect to the upper surface of the conveyor belt 5. Line heads 11C, 11M, 11Y and 11K are disposed. These line heads 11C to 11K are respectively supplied with four colors (cyan, magenta, yellow and black) of ink stored in the ink tank 20 (see FIG. 5). A color image is formed on the paper P by ejecting ink.

  As shown in FIG. 2, these line heads 11 </ b> C to 11 </ b> K have a plurality of (in this case, three) recording heads 13 arranged in a staggered manner in a direction orthogonal to the paper conveyance direction, and the width of the paper P being conveyed. Having the above recording area, the image for one line can be recorded collectively on the paper P conveyed on the conveying belt 5. In addition, each recording head 13 is arranged so that a part of the ink discharge nozzles 15 provided in each recording head 13 overlap in the transport direction.

  As the ink ejection method of the line heads 11C to 11K, for example, a piezo method that pushes out ink using a piezo element (not shown), or a thermal ink jet method that generates air bubbles by a heating element and ejects ink by applying pressure. Various methods can be applied.

  The recording heads 13 of the line heads 11 </ b> C to 11 </ b> K eject ink from the recording head 13 toward the paper P placed on the surface of the transport belt 5 in accordance with image data information received from an external computer or the like. As a result, a color image is formed on the paper P on the transport belt 5 by superimposing four colors of ink of cyan, magenta, yellow, and black. The paper P on which the color image is formed is discharged to the discharge tray 10 provided outside the right side surface of the inkjet recording apparatus 100 via the discharge roller 8 and the driven roller 9.

  In addition, in order to prevent ink discharge failure due to drying or clogging of the recording head 13, the ink discharge amount is a specified value from all the recording heads 13 at the start of printing after a long-term stop and between printing operations. In order to prepare for the next printing operation, the following purge is performed to eject ink with increased viscosity in the nozzle from the nozzles of the recording head 13.

  Next, ink supply from the ink tank 20 to the recording head 13 during printing and ink ejection from the recording head 13 during purging will be described. FIG. 5 is a diagram schematically showing an ink flow path from the ink tank 20 to the recording head 13 of the ink jet recording apparatus 100 of the present invention. Note that the ink flow paths shown in FIG. 5 are provided between the ink tanks 20 for the respective colors and the recording head 13, but here, the ink flow paths for any one color will be described.

  As shown in FIG. 5, a syringe pump 21 is disposed between the ink tank 20 and the recording head 13. The ink tank 20 and the syringe pump 21 are connected by a first supply path 23 made of a tube member, and the syringe pump 21 and the ink discharge nozzle 15 in the recording head 13 are connected by a second supply path 25 made of a tube member. Yes.

  The first supply path 23 is provided with an inflow side valve 27, and the second supply path 25 is provided with an outflow side valve 29. By opening and closing the inflow side valve 27, the movement of ink in the first supply path 23 is permitted or restricted, and by opening and closing the outflow side valve 29, the movement of ink in the second supply path 25 is permitted or restricted. .

  The syringe pump 21 includes a cylinder 21a and a piston 21b. The cylinder 21 a is connected to the first supply path 23 and the second supply path 25, and the ink 22 in the ink tank 20 flows into the cylinder 21 a through the first supply path 23. Further, ink is discharged from the cylinder 21a through the second supply path 25, and the discharged ink is supplied to the recording head 13 and discharged from the nozzle region R of the ink discharge surface 13a.

  The piston 21b can be moved up and down by a drive device (not shown). A packing (not shown) such as an O-ring is mounted on the outer periphery of the piston 21b to prevent ink leakage from the cylinder 21a, and the piston 21b can slide smoothly along the inner peripheral surface of the cylinder 21a. It is like that.

  During normal printing (during printing), as shown in FIG. 5, the inflow side valve 27 and the outflow side valve 29 are both in an open state, and the piston 21b is stopped at a preset position so that the inside of the cylinder 21a Is filled with a substantially constant amount of ink. Ink 22 is supplied from the cylinder 21 a to the recording head 13 by the surface tension (meniscus) between the cylinder 21 a and the recording head 13.

  FIG. 6 is a perspective view of the wiping mechanism 30 for wiping the ink discharge surface 13a of the recording head 13 as viewed obliquely from above, and FIGS. 7 and 8 are perspective views of the wiping mechanism 30 as viewed from obliquely below. The wiping mechanism 30 includes a first wiper 33 fixed to the first carriage 31 and a second wiper 34 fixed to the second carriage 32. For convenience of explanation, in FIG. 7 and FIG. 8, only the portion where the first carriage 31 is fixed to the first wiper 33 is shown, and the support frame 40 is not shown. 7 shows a state in which the first wiper 33 and the second wiper 34 are both in pressure contact with the ink discharge surface 13a, and FIG. 8 shows a state in which the second wiper 34 is separated from the ink discharge surface 13a. .

  The first carriage 31 is supported by a support frame 40 disposed below the recording head 13. The second carriage 32 is held so as to be movable in the vertical direction with respect to the first carriage 31. Below the second carriage 32, a pair of arm members 35 are swingably supported by the first carriage 31 with a substantially central portion in the longitudinal direction as a fulcrum. One end (left end in FIGS. 7 and 8) of each arm member 35 is in contact with the lower surface of the second carriage 32, and a projection 35a is formed on the other end (right end in FIGS. 7 and 8).

  A lower end portion of the coil spring 36 is extrapolated to the protrusion 35 a of each arm member 35, and the upper end portion of the coil spring 36 is fixed to a spring receiving portion 31 a formed at the end portion of the first carriage 31. With this configuration, the second carriage 32 is urged upward by the arm member 35 and the coil spring 36.

  At the lower end of the first carriage 31, rack teeth 31 b that mesh with the input gear 37 (see FIG. 4) held by the support frame 40 are formed. When the input gear 37 rotates in the forward and reverse directions, the first carriage 31 and the second carriage 32 reciprocate in the horizontal direction along the support frame 40. Note that the support frames 40 arranged below a plurality of (in this case, 12) recording heads 13 constituting the line heads 11C to 11K are connected (integrated).

  The first wiper 33 is in pressure contact with the wiping start position S outside the nozzle region R (see FIG. 5) where the nozzle surface of the ink discharge nozzle 15 is exposed from the substantially vertical direction, and the nozzle region R is moved by the movement of the first carriage 31. The ink discharge surface 13a that is included is wiped off in a predetermined direction (the direction of arrow A in FIG. 7). Thereafter, the first wiper 31 is moved away from the ink ejection surface 13a in the reverse direction (in the direction of arrow A ′ in FIG. 7), and is again brought into pressure contact with the wiping start position S.

  The second wiper 34 is arranged on the upstream side of the first wiper 33 with respect to the wiping direction (arrow A direction) of the ink discharge surface 13a. The second wiper 34 is in pressure contact with the upstream side of the wiping start position S from a substantially vertical direction, and wipes between the downstream side of the wiping start position S and the upstream side of the nozzle region R in the same direction as the first wiper 33. . After that, as shown in FIG. 8, the boss portion 32a of the second carriage 32 rides on the guide rail 42 formed on the recording head side frame 41 (see FIG. 3) to which the recording head 13 is fixed, whereby the second wiper 34 is separated from the ink ejection surface 13a. Then, after moving to the downstream end of the ink ejection surface 13a in the wiping direction, it moves in the reverse direction (in the direction of arrow A 'in FIG. 7) together with the first wiper 33, and is pressed against the upstream side of the wiping start position S again. . 7 and 8, the recording head side frame 41 is not shown, and only the guide rail 42 is shown.

  Returning to FIG. 4, an elevating mechanism 50 including a lift member 50 a and a shaft 50 b is disposed below the support frame 40. FIG. 9 is a front view of the lifting mechanism 50 as viewed from the downstream side in the paper discharge direction (the left front side in FIG. 3). In FIG. 9, the description of the central recording head 13 among the three recording heads 13 constituting each of the line heads 11C to 11K is omitted.

  The elevating mechanism 50 is provided in the maintenance unit 51 disposed below the recording head side frame 41 when the recovery operation of the recording head 13 is executed, and both ends in the width direction of the recording head side frame 41 (left and right in FIG. 9). It is arrange | positioned in the position facing both ends. The lower end portion of the lift member 50a is fixed to the shaft 50b, and a roller 53 is rotatably attached to the upper end portion of the lift member 50a. The roller 53 is engaged with the rail portion 40a of the support frame 40, and is rotatable along the rail portion 40a.

  9, when the right shaft 50b is rotated in the counterclockwise direction and the left shaft 50b is rotated in the clockwise direction, the lift member 50a falls inward (in the direction of arrow B) of the maintenance unit 51, and the roller 53 is moved. It moves to the inner end of the rail portion 40a. Accordingly, the lift member 50a is switched from the standing state (the state shown in FIG. 9) to the horizontal state, and the first carriage 31 and the second carriage 32 are lowered together with the support frame 40.

  Next, when the right shaft 50b is rotated in the clockwise direction and the left shaft 50b is rotated in the counterclockwise direction, the lift member 50a that has fallen into the inside of the maintenance unit 51 rises in the outer direction (arrow B ′ direction), 53 moves to the outer end of the rail portion 40a. Thereby, the lift member 50a is switched from the horizontal state to the standing state (the state shown in FIG. 9), and the first carriage 31 and the second carriage 32 are raised together with the support frame 40.

  As shown in FIG. 9, two first wipers 33 are fixed to both ends of the first carriage 31, one in total. The second carriage 32 to which the second wiper 34 is fixed is also supported at both ends of the first carriage 31 so as to be swingable. That is, in the configuration shown in FIG. 9, the wiping mechanism 30 is provided at both ends of the first carriage 31, and the inks of the two recording heads 13 are moved by the reciprocating movement of the first carriage 31 and the raising / lowering operation by the lifting mechanism 50. The discharge surface 13a can be wiped simultaneously.

  10 to 17 are side views showing the behavior of the first wiper 33 and the second wiper 34 during the wiping operation of the recording head 13. The wiping operation of the recording head 13 using the wiping mechanism 30 of the present invention will be described with reference to FIGS. 10 to 17, similarly to FIGS. 7 and 8, the first carriage 31 shows only one side portion to which the first wiper 33 is fixed, and the support frame 40 is not shown. Further, only the guide rail 42 is shown in the recording head side frame 41.

  When performing the recovery operation of the recording head 13, first, prior to the wiping operation, in a state where printing is not being performed by the recording head 13, the inflow side valve 27 (see FIG. 5) is closed, and the syringe pump 21 (see FIG. 5). ) Is supplied, the ink 22 in the cylinder 21 a is supplied to the recording head 13 through the second supply path 25. The supplied ink 22 is forcibly ejected (purged) from the ink ejection nozzle 15 to the ink ejection surface 13a. By this purge operation, the thickened ink, foreign matter, and bubbles in the ink discharge nozzle 15 are discharged, and the recording head 13 can be recovered.

  Next, a wiping operation for wiping off the ink 22 ejected onto the ink ejection surface 13a is performed. Specifically, by lifting the support frame 40 and the wiping mechanism 30 using the elevating mechanism 50 (see FIG. 9), as shown in FIG. 10, the first wiper 33 from a direction substantially perpendicular to the ink ejection surface 13a. And the second wiper 34 are pressed against the upstream side of the wiping start position S (on the right side of the wiping start position S in FIG. 10).

  Then, by rotating the input gear 37 (see FIG. 4) forward and moving the first carriage 31 and the second carriage 32 in the direction of arrow A as shown in FIG. The ink 22 discharged to the surface is wiped off. The ink wiped off by the first wiper 33 is collected in a disposal tank (not shown). In the middle of moving the second carriage 32 in the direction of arrow A, as shown in FIG. 12, the boss portion 32a of the second carriage 32 rides on a guide rail 42 provided substantially parallel to the ink ejection surface 13a. .

  As a result, the second carriage 32 moves downward by a predetermined distance while pressing the end of the arm member 35 on the carriage side and compressing the coil spring 36. As a result, the second wiper 34 is also separated from the ink ejection surface 13a by a predetermined distance on the upstream side of the nozzle region R (see FIG. 10), and moves in the direction of arrow A together with the first wiper 33.

  After the first wiper 33 and the second wiper 34 have moved to the downstream end of the ink ejection surface 13a, the support frame 40 and the wiping mechanism 30 are lowered using the lifting mechanism 50, whereby the first carriage 31 and the second wiper 34 are moved downward. The carriage 32 is retracted downward from the ink ejection surface 13a. At this time, since the boss portion 32a of the second carriage 32 falls off from the guide rail 42, the compressed coil spring 36 extends and pushes down the end portion of the arm member 35 on the coil spring 36 side, so that the arm member 35 on the carriage side. The end lifts the second carriage 32. As a result, the second carriage 32 moves upward (in the direction of the ink ejection surface 13a) by a fixed distance, and the first carriage 31 and the second carriage 32 return to the positional relationship before the boss portion 32a rides on the guide rail 42.

  Thereafter, by rotating the input gear 37 in the reverse direction, the first carriage 31 and the second carriage 32 are moved in the direction of the arrow A ′, and the first wiper 33 is again moved to the wiping start position S as shown in FIG. The wiper 34 returns to the upstream side of the wiping start position S. At this time, the ink 22 is attached to the tip and side surfaces of the first wiper 33.

  In this state, when the second recovery operation and wiping operation of the recording head 13 are performed, when the first wiper 33 is pressed against the wiping start position S, as shown in FIG. The ink 22 adheres to the upstream side of the wiping start position S due to the bending of the first wiper 33, and the ink reservoir 22a is generated. As shown in FIG. 15, the ink reservoir 22a moves to the downstream side when the second wiper 34 pressed against the upstream side of the wiping start position S moves in the wiping direction (arrow A direction). As shown in FIG. 16, the ink reservoir 22a remains in the vicinity of the upstream side of the nozzle region R where the second wiper 34 is separated from the ink ejection surface 13a.

  After the second wiping operation, as shown in FIG. 17, the first wiper 33 returns to the wiping start position S and the second wiper 34 returns to the upstream side of the wiping start position S again. Since the ink reservoir 22a generated by the second wiping operation is shifted downstream from the wiping start position S by the second wiper 34, it can be wiped by the first wiper 33 during the third wiping operation.

  Even during the third wiping operation, the ink 22 adhering to the tip of the first wiper 33 adheres adjacent to the upstream side of the wiping start position S, and an ink reservoir 22a is generated. This ink reservoir 22a Since it moves downstream by the second wiper 34, it can be wiped off by the first wiper 33 during the fourth wiping operation.

  That is, even when the wiping operation is repeated, only the ink reservoir 22a corresponding to one wiping operation is always generated, so there is no possibility that the ink reservoir 22a collects to form a large ink reservoir. Therefore, it is possible to effectively suppress the problem that the ink reservoir falls on or contacts the paper P passing under the ink ejection surface 13a and soils the paper P.

  In addition, since the second wiper 34 is separated from the ink discharge surface 13 a on the upstream side of the nozzle region R, excess ink 22 does not adhere to the tip of the second wiper 34. Therefore, when the second wiper 34 is brought into pressure contact with the ink ejection surface 13a during the second and subsequent wiping operations, there is no possibility that the ink reservoir 22a is generated unlike the first wiper 33.

  The wiping operation by the first wiper 33 and the second wiper 34 described above is simultaneously performed on the plurality of recording heads 13 constituting the line heads 11C to 11K. Specifically, using the lifting mechanism 50 (see FIG. 9), the plurality of first carriages 31 and second carriages 32 arranged corresponding to the respective recording heads 13 are simultaneously lifted and lowered together with the support frame 40 to support the support frame. By simultaneously rotating a plurality of input gears 37 (see FIG. 4) provided in 40 in the same direction, the plurality of first carriages 31 and second carriages 32 are simultaneously moved horizontally in the same direction along the support frame 40. . Thereby, the maintenance time of the recording head 13 can be shortened, and the drive control during the maintenance can be simplified.

  In addition, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, the second wiper 34 (second carriage 32) moves together with the first wiper 33 (first carriage 31) to the downstream end of the ink ejection surface 13a in the wiping direction. The second wiper 34 only needs to have a function of moving the ink reservoir 22a generated by the pressure contact of the first wiper 33 during the second and subsequent wiping operations to the downstream side. Accordingly, the second wiper 34 (second carriage 32) is driven separately from the first wiper 33 (first carriage 31), and immediately after the second wiper 34 is separated from the ink ejection surface 13a on the upstream side of the nozzle region R. You may make it return to the upstream of the wiping start position S.

  Further, as for the driving mechanism of the first carriage 31 and the second carriage 32 configured by the rack teeth 31a and the input gear 37, or the lifting mechanism 50 configured by the lift member 50a and the shaft 50b, other conventionally known driving mechanisms are also used. Can be used.

  Further, the number of ink discharge nozzles 15 and the nozzle interval of the recording head 13 can be appropriately set according to the specifications of the ink jet recording apparatus 100. Further, the number of the recording heads 13 is not particularly limited. For example, one recording head 13 can be arranged for each of the line heads 11C to 11K.

  The present invention is applicable to an ink jet recording apparatus that performs recording by ejecting ink from a recording head. By utilizing the present invention, when the wiper is brought into pressure contact with the ink ejection surface from a substantially vertical direction, a large ink pool due to repeated wiping operations does not occur. The ink jet recording apparatus can prevent sticking and breakage and improve durability.

11C to 11K Line head 13 Recording head 13a Ink discharge surface 15 Ink discharge nozzle 20 Ink tank 21 Syringe pump 22 Ink 22a Ink reservoir 30 Wiping mechanism 31 First carriage 31b Rack teeth (drive mechanism)
32 Second carriage 32a Boss portion 33 First wiper 34 Second wiper 35 Arm member (biasing member)
36 Coil spring (biasing member)
37 Input gear (drive mechanism)
40 Support Frame 41 Recording Head Side Frame 42 Guide Rail 50 Elevating Mechanism 100 Inkjet Recording Device S Wiping Start Position R Nozzle Area

Claims (4)

A recording head wiping mechanism for wiping the ink discharge surface of a recording head provided with a nozzle area where an ejection nozzle for discharging ink is opened on a recording medium with a wiper,
After wiping the ink discharge surface including the nozzle region in a predetermined direction, the ink is wiped away from the ink discharge surface and moved in the direction opposite to the wiping direction. A first wiper pressed against the wiping start position again,
After wiping in the same direction as the first wiper between the downstream side of the wiping start position and the upstream side of the nozzle region, the pressure wiped from the direction substantially perpendicular to the upstream side of the wiping start position relative to the wiping direction, A second wiper that is separated from the ink ejection surface and is pressed against the upstream side of the wiping start position again;
A wiping mechanism comprising: A first carriage that is reciprocally movable along the ink ejection surface and to which the first wiper is fixed;
A second carriage supported by the first carriage so as to be swingable in a direction approaching or separating from the ink ejection surface, and the second wiper being fixed thereto;
A biasing member that biases the second carriage in a direction approaching the ink ejection surface;
A support frame for reciprocally supporting the first carriage;
A guide rail fixed substantially parallel to the ink ejection surface;
A drive mechanism for reciprocating the first carriage along the support frame;
An elevating mechanism that elevates and lowers the support frame together with the first carriage in a direction approaching or separating from the ink ejection surface;
Further comprising
The second wiper is separated from the ink ejection surface upstream of the nozzle region by the second carriage riding on the guide rail as the first carriage moves in the wiping direction. Item 2. A wiping mechanism according to Item 1.   The driving mechanism and the lifting mechanism are configured to simultaneously reciprocate and lift the plurality of first carriages and second carriages provided corresponding to the plurality of recording heads, thereby causing the first wiper and the second lifting mechanism to move up and down. The wiping mechanism according to claim 2, wherein the ink discharge surfaces of the plurality of recording heads are simultaneously wiped by a wiper.   An ink jet recording apparatus comprising the wiping mechanism according to any one of claims 1 to 3.

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