Ink jet recording device

Abstract

To prevent cleaning fluid from entering a gap between a supply member and a nozzle plate.SOLUTION: An ink jet recording device includes: a blade 82 which performs a wiping operation along a nozzle surface 14F of a nozzle plate 14; a supply member 41 which is provided on an advancing direction A rear side in the wiping operation of the nozzle plate 14, has a narrower dimension in a width direction crossing the advancing direction A than the blade 82 and supplies cleaning fluid F to the blade 82 by contact with a tip of the blade 82; and a receiving and delivering member 44 projecting to an advancing direction A front side from the supply member 41. The receiving and delivering member 44 has a bottom section 44B which is provided along a lower surface of the supply member 41 and is brought into contact with the nozzle surface 14F when an ink jet head is lowered, and a side section 44W which is provided along a side face 532 in the width direction of the supply member 41 and closes a gap G1 between the nozzle plate 14 and the supply member 41 when the ink jet head is lowered.SELECTED DRAWING: Figure 34

Description

Technical Field

[0001] The present invention relates to an inkjet recording apparatus.

Background Art

[0002] In an inkjet recording apparatus, during a period when an image forming job is not being executed, moisture may evaporate from the ink in the nozzles of the inkjet head, and the nozzles may become clogged due to an increase in the viscosity of the ink. Therefore, a purge process is performed to discharge the ink in the nozzles for the purpose of preventing clogging. However, if the ink remaining on the nozzle surface is left unattended, there are problems such as ink dropping onto the sheet during the execution of an image forming job or the ink adhering to the nozzle surface. Therefore, techniques for removing the ink remaining on the nozzle surface have been studied. For example, in Patent Document 1, a configuration is proposed in which ink is removed from the nozzle surface by sliding a blade that contacts the nozzle surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration disclosed in Patent Document 1, when the blade carries the cleaning liquid forward during the wiping operation, the cleaning liquid pushed to both end sides in the width direction of the blade is pushed up along the side surface of the supply member, and enters the gap between the supply member and the nozzle plate (head portion), and the gap between the nozzle surface and the transfer member (the thin plate-like portion of the cleaning liquid supply surface). When the wiping operation is completed and the inkjet head rises, a part of the cleaning liquid that has entered the gap may remain on the nozzle plate and may drop onto the sheet during image formation.

[0005] In view of the above circumstances, an object of the present invention is to prevent the cleaning liquid from entering the gap between the supply member and the nozzle plate.

Means for Solving the Problems

[0006] To solve the above problems, an inkjet recording apparatus according to the present invention includes an inkjet head having a nozzle plate, a head lifting device for lifting and lowering the inkjet head, a blade that performs a wiping operation along the nozzle surface of the nozzle plate, and a supply member that is provided on the rear side in the advancing direction of the wiping operation with respect to the nozzle plate and has a dimension in the width direction intersecting the advancing direction that is narrower than the blade, and supplies the cleaning liquid to the blade by contact with the tip of the blade, and a delivery member that protrudes forward in the advancing direction from the supply member, the delivery member is provided along the lower surface of the supply member, and includes a bottom portion that contacts the nozzle surface when the inkjet head descends, and a side portion that is provided along the side surface in the width direction of the supply member and closes the gap between the nozzle plate and the supply member when the inkjet head descends.

[0007] The side portion of the delivery member may close the gap between the bottom portion and the nozzle surface when the inkjet head descends.

[0008] The bottom portion of the delivery member may be inclined so that the tip side is higher.

[0009] The delivery member may have flexibility.

Effects of the Invention

[0010] According to the present invention, it is possible to prevent the cleaning liquid from entering the gap between the supply member and the nozzle plate.

Brief Description of the Drawings

[0011]

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Mode for Carrying Out the Invention

[0012] Hereinafter, an inkjet recording apparatus 1 according to an embodiment of the present invention will be described with reference to the drawings.

[0013] FIG. 1 is a perspective view showing the appearance of an image forming system 100. FIG. 2 is a front view schematically showing the internal configuration of the inkjet recording apparatus 1. FIG. 3 is a front view schematically showing the head unit 11 and the maintenance apparatus 30. FIG. 4 is a plan view schematically showing the head unit 11 and the wipe unit 32. FIG. 5 is a plan view schematically showing the cap unit 31. FIG. 6 is a cross-sectional view showing the inkjet head 12. Hereinafter, the front side (front side) of the inkjet recording apparatus 1 will be the front side of the paper surface in FIG. 2, and the left and right directions will be described based on the direction of viewing the inkjet recording apparatus 1 from the front. In each figure, U, Lo, L, R, Fr, and Rr indicate up, down, left, right, front, and rear, respectively.

[0014] The image forming system 100 (see FIG. 1) includes a paper feeding device 110, an inkjet recording apparatus 1, a drying device 120, and a post-processing device 130. The paper feeding device 110 stores thousands of sheets and supplies the sheets to the inkjet recording apparatus 1. The inkjet recording apparatus 1 forms an image on the sheet by an inkjet method. The drying device 120 heats the sheet conveyed from the inkjet recording apparatus 1 to dry the ink. The post-processing device 130 performs post-processing such as punching, stapling, and folding on the sheet conveyed from the drying device 120.

[0015] The inkjet recording apparatus 1 (see Fig. 2) includes a rectangular parallelepiped main body housing 3. A conveyance unit 7 for adsorbing a sheet and conveying it in the Y direction is provided at the central part inside the main body housing 3. An image forming unit 6 for discharging ink to form an image is provided above the conveyance unit 7. A paper feed port 8 for introducing a sheet from a paper feeding device 110 is provided on the right side surface of the main body housing 3. A discharge port 9 for discharging the sheet on which an image has been formed to a drying device 120 is provided on the left side surface of the main body housing 3. A conveyance path 10 is provided inside the main body housing 3, which extends from the paper feed port 8 through the gap between the conveyance unit 7 and the image forming unit 6 to the discharge port 9. A registration roller 18 is provided upstream of the conveyance unit 7 in the conveyance direction Y.

[0016] The conveyance unit 7 includes an endless conveyance belt 21 and a suction unit 24. The conveyance belt 21 has a number of ventilation holes (not shown) and is wound around a driving roller 25 and a driven roller 22. The upper surface of the suction unit 24 has a number of ventilation holes (not shown) and is in contact with the inner surface of the conveyance belt 21. By the suction unit 24 sucking air through the ventilation holes of the conveyance belt 21 and the ventilation holes of the suction unit 24, the sheet is adsorbed to the conveyance belt 21. The driving roller 25 is driven in the counterclockwise direction by a driving unit (not shown) including a motor and a reduction gear, so that the conveyance belt 21 rotates in the counterclockwise direction, and the sheet adsorbed to the conveyance belt 21 is conveyed in the Y direction.

[0017] The image forming unit 6 includes a plurality (four in this embodiment) of head units 11. The head unit 11 (see Figs. 3 and 4) includes one or more (three in this embodiment) inkjet heads 12. Ink containers 20 filled with black, cyan, magenta, and yellow inks are respectively connected to each head unit 11.

[0018] The inkjet head 12 (see FIG. 6) includes a rectangular parallelepiped housing 12H having a longitudinal direction in the front-rear direction, a nozzle plate 14 provided at the bottom of the housing 12H, and a socket 12S to which a pipe for supplying ink is connected. The nozzle plate 14 includes a large number of nozzles 14N arranged in the front-rear direction. The nozzle 14N includes a branch flow path 14B branched from the downstream side of the socket 12S and a discharge port 14A provided on a nozzle surface 14F which is the lower surface of the nozzle plate 14. The diaphragm 14V also serves as a part of the inner wall of the branch flow path 14B. A pressurizing element 14Z is provided on the diaphragm 14V. As the pressurizing element 14Z, a piezoelectric element, an electrostatic actuator, a heater, or the like is used. A drive circuit 12D for driving the pressurizing element 14Z is connected to the pressurizing element 14Z.

[0019] The control unit 2 (see FIG. 2) includes an arithmetic unit and a storage unit (not shown). The arithmetic unit is, for example, a CPU (Central Processing Unit). The storage unit includes storage media such as a ROM (Read Only Memory), a RAM (Random Access Memory), and an EEPROM (Electrically Erasable Programmable Read Only Memory). The arithmetic unit performs various processes by reading and executing a control program stored in the storage unit. Note that the control unit 2 may be realized by an integrated circuit that does not use software.

[0020] A display operation unit 19 is provided on the upper part of the main body housing 3 (see FIGS. 1 and 2). The display operation unit 19 includes a display panel, a touch panel laminated on the display panel, and a keypad (not shown). The control unit 2 causes the display panel to display a screen representing an operation menu, status, etc. of the inkjet recording apparatus 1, and controls each part of the inkjet recording apparatus 1 according to operations detected by the touch panel and the keypad.

[0021] The basic image forming operation of the inkjet recording apparatus 1 is as follows. When an image forming job is input to the inkjet recording apparatus 1 from the display operation unit 19, an external computer, or the like, the paper feeding apparatus 110 feeds a sheet into the conveyance path 10 through the paper feed port 8, and the registration roller 18 whose rotation has been stopped corrects the skew of the sheet. When the registration roller 18 feeds the sheet to the conveyance unit 7 at a predetermined timing, the conveyance unit 7 sucks the sheet onto the conveyance belt 21 and conveys it in the Y direction. Ink is ejected from the inkjet head 12 onto the sheet to form an image. The sheet on which the image has been formed is conveyed to the drying apparatus 120 through the discharge port 9.

[0022] [Maintenance Device] Next, the maintenance device 30 will be described. Since the four head units 11 (see FIG. 2) have the same configuration and the four maintenance devices 30 have the same configuration, hereinafter, one head unit 11 and one maintenance device 30 that performs maintenance on this head unit 11 will be described.

[0023] [Head Base] The head unit 11 includes a head base 11B (see FIGS. 3, 4, and 6) that supports the inkjet head 12. Three inkjet heads 12 are provided on the head base 11B in a staggered manner. The head base 11B is a generally rectangular plate-like member whose longitudinal direction is the front-rear direction. The head base 11B is provided with a through hole (not shown) into which the nozzle plate 14 of the inkjet head 12 is inserted. The lower surface of the head base 11B is a surface parallel to the nozzle surface 14F (hereinafter referred to as the parallel surface 11P). The nozzle surface 14F protrudes downward from the parallel surface 11P.

[0024] The maintenance device 30 (see FIG. 3) is provided on the side of the head unit 11 (in this embodiment, on the upstream side (right side) in the conveyance direction Y). The maintenance device 30 includes a cap unit 31, a wipe unit 32, and a cleaning liquid supply source 13.

[0025] [Cap Unit] The cap unit 31 (see FIGS. 3 and 5) includes the same number of caps 72 (three in this embodiment) as the inkjet head 12 included in the head unit 11. The three caps 72 are arranged staggeredly in the same manner as the inkjet head 12 and are supported by the frame 71.

[0026] [Wiper Unit] The wiper unit 32 (see FIGS. 3 and 4) includes a waste liquid tray 81, a blade 82, and a cleaning liquid supply unit 40. The waste liquid tray 81 includes the same number of recesses 81U as the inkjet head 12 included in the head unit 11. The plurality of recesses 81U are arranged staggeredly in the same manner as the inkjet head 12. The blade 82 and the cleaning liquid supply unit 40 are provided in each of the recesses 81U.

[0027] [Head Lifting Device] FIG. 23 is a front view showing the operation of the maintenance device 30. The head lifting device 11L (see FIG. 4) is provided in front of and behind the head base 11B. The head lifting device 11L is composed of, for example, a ball screw, a belt drive device, etc. The head lifting device 11L raises and lowers the head unit 11 between an image forming position (see FIG. 23(A)) and a retracted position (see FIG. 23(B)). The image forming position is a position where the distance between the conveyance path 10 (the upper surface of the conveyance belt 21) along which the sheet is conveyed and the nozzle surface 14F is a predetermined distance suitable for image formation. The retracted position is a position above the image forming position and is a position where the head unit 11 does not interfere with the wiper unit 32 when the cap slide device 34 described later is used to slide the cap unit 31 and the wiper unit 32 in the horizontal direction.

[0028] [Cap Slide Device] The cap slide device 34 (see Fig. 5) is provided before and after the frame 71 of the cap unit 31. The cap slide device 34 is composed of, for example, a ball screw, a belt drive device, etc. The cap slide device 34 slides the cap unit 31 between a home position (see Fig. 23(A)) and a maintenance position (see Fig. 23(F)). The home position is a position to the right of the head unit 11 located at the image forming position. The maintenance position is a position below the head unit 11 located at the retracted position.

[0029] [Wiper lifting device] The wiper lifting device 35 (see Fig. 4) is provided before and after the waste liquid tray 81 of the wiper unit 32. The wiper lifting device 35 is composed of, for example, a cam mechanism, a ball screw, etc. The wiper lifting device 35 raises and lowers the wiper unit 32 between a contact position (see Fig. 23(B)) and a separated position (see Fig. 23(E)). The contact position is a position where the waste liquid tray 81 contacts the cap 72. The separated position is a position where the waste liquid tray 81 is separated upward from the cap 72 by a predetermined distance.

[0030] When the wiper unit 32 is in the contact position, since the wiper unit 32 is placed on the cap unit 31, by operating the cap slide device 34, the wiper unit 32 slides together with the cap unit 31 between the home position and the maintenance position. That is, the cap slide device 34 also functions as a wiper slide device for sliding the wiper unit 32 between the home position and the maintenance position. When the wiper unit 32 is in the separated position, by operating the cap slide device 34, the cap unit 31 slides between the home position and the maintenance position alone while leaving the wiper unit 32 in the home position.

[0031] [Wiper unit] Next, the configuration of the wiper unit 32 will be described in detail. FIG. 7 is a perspective view showing the wiper unit 32 and the cleaning liquid supply source 13. FIG. 8 is a perspective view showing the wiper unit 32. FIG. 9 is a perspective view showing the blade unit 90. FIG. 10 is a perspective view showing a cross section of the blade unit 90. FIG. 11 is a perspective view showing the protruding member 91 and the blade 82. FIG. 12 is a perspective view showing the protruding member 91.

[0032] The wiper unit 32 (see FIG. 7) includes a plurality (three in this embodiment) of blade units 90, a waste liquid tray 81, and a carriage 83. The blade unit 90 (see FIGS. 11 and 12) includes a blade 82, a protruding member 91, a holder 92, and a first biasing member 93.

[0033] [Blade] The blade 82 (see FIGS. 9 to 11) is a flexible, generally rectangular plate-like member formed of resin or the like. The blade 82 is held by the holder 92 in a slightly rearwardly inclined posture with the front-rear direction as the thickness direction. The width of the blade 82 in the left-right direction is equal to or greater than the width of the nozzle surface 14F. A taper is provided at the upper part of the blade 82 such that the thickness becomes thinner as it approaches the tip.

[0034] [Protruding member] The protruding member 91 (see FIGS. 9 to 12) is integrated with the blade 82. The protruding member 91 includes a base portion 91B parallel to the blade 82, a first bent portion 911 bent rearward from the upper end portion of the base portion 91B, a second bent portion 912 bent upward from the rear end portion of the first bent portion 911, a rearwardly inclined portion 91T inclined more rearwardly than the second bent portion 912, and protruding portions 91P protruding upward from both left and right end portions of the rearwardly inclined portion 91T and inclined at the same inclination angle as the rearwardly inclined portion 91T.

[0035] The width of the base 91B in the left - right direction is equal to the width of the blade 82. The length of the base 91B in the up - down direction is shorter than the length of the blade 82 in the up - down direction. The base 91B is joined to the lower part of the rear surface of the blade 82. The width of the first bent portion 911 and the second bent portion 912 in the left - right direction is equal to the width of the base 91B. The width of the rear - inclined portion 91T in the left - right direction is wider than the width of the base 91B. The left - right position of the protruding portion 91P is determined such that the tip of the protruding portion 91P can contact the left - right parallel planes 11P of the nozzle surface 14F.

[0036] On the rear surface of the base 91B, two wall portions 91C facing each other in the left - right direction are provided (see FIGS. 11 and 12). On the left surface of the left wall portion 91C, a shaft portion 91S protruding leftward is provided. On the right surface of the right wall portion 91C, a shaft portion 91S protruding rightward is provided.

[0037] In the central portion of the first bent portion 911 in the left - right direction, a through - hole 91A penetrating downward is provided (see FIGS. 11 and 12). At least a part of the waste liquid W (a mixture of ink and cleaning liquid) flowing down along the rear surface of the blade 82 falls downward through the through - hole 91A.

[0038] [Fixing member] The fixing member 94 (see FIGS. 9 to 11) fixes the blade 82 to the protruding member 91. The lower part of the blade 82 is sandwiched between the base 91B of the protruding member 91 and the fixing member 94, and the fixing member 94 is fastened to the protruding member 91. The lower edge of the fixing member 94 and the lower edge of the protruding member 91 are provided with a taper (see FIGS. 9 and 12) whose width in the left - right direction becomes narrower downward. The waste liquid flowing down from the front surface of the blade 82 to the front surface of the fixing member 94 gathers at the center in the left - right direction along the lower edge of the fixing member 94 and the lower edge of the protruding member 91, and falls into the recess 81U of the waste - liquid tray 81.

[0039] [Holder] The holder 92 (see FIGS. 9 to 11) holds the blade 82 via the protruding member 91. A shaft hole 92H into which the shaft portion 91S of the protruding member 91 is inserted is provided at the lower part of the holder 92. The protruding member 91 is swingable in the front-rear direction about the shaft portion 91S. The blade 82 swings together with the protruding member 91. The blade 82 and the protruding member 91 are provided on the holder 92 in a posture inclined with respect to the left-right direction so that the waste liquid W flows in either one direction in the left-right direction. In the illustrated example, the left end portion of the blade 82 is inclined so as to be slightly rearward of the right end portion, but it may be inclined in the reverse direction.

[0040] [First biasing member] The first biasing member 93 (see FIGS. 11 and 12) is, for example, a torsion coil spring and is wound around the shaft portion 91S. One end portion of the first biasing member 93 engages with the holder 92, and the other end portion engages with the protruding member 91. The first biasing member 93 biases the protruding member 91 in the counterclockwise direction in FIGS. 9 and 10 and in the clockwise direction in FIG. 11. In other words, the first biasing member 93 biases the blade 82 in the direction of pressing the tip portion of the blade 82 against the nozzle surface 14F. Note that the first biasing member 93 may be a leaf spring, a compression coil spring, or the like.

[0041] [Waste liquid tray] The waste liquid tray 81 (see FIGS. 7 and 8) is formed in a rectangular shape with the longitudinal direction in the front-rear direction as a whole. The waste liquid tray 81 includes three recesses 81U that are open at the upper side. The three recesses 81U are arranged in a staggered pattern similar to the inkjet head 12. The recess 81U is formed in a rectangular shape that is elongated in the front-rear direction when viewed from above. The length of the recess 81U in the front-rear direction is longer than the nozzle surface 14F, and the width of the recess 81U in the left-right direction is wider than the nozzle surface 14F. The recess 81U receives waste liquid containing ink and cleaning liquid.

[0042] [Carriage] The carriage 83 (see FIGS. 7 to 10) is formed in a plate shape with the longitudinal direction being the front-rear direction. A groove 81G extending in the front-rear direction is provided between the left and right concave portions 81U, and the carriage 83 is accommodated in the groove 81G. The length of the carriage 83 in the front-rear direction is shorter than the length of the groove 81G in the front-rear direction. The carriage 83 is slidable in the front-rear direction along the groove 81G.

[0043] The three concave portions 81U each accommodate a blade unit 90. The three blade units 90 are coupled to the carriage 83. The three blade units 90 are arranged on the carriage 83 such that when the carriage 83 is located at the rearmost position, the three blade units 90 are located behind the nozzle surface 14F.

[0044] [Carriage driving device] The waste liquid tray 81 is provided with a carriage driving device 36 (see FIG. 4). The carriage driving device 36 is composed of, for example, a belt driving device, a feed screw, etc., and slides the carriage 83 along the groove 81G to slide the blade 82. By sliding the blade 82 forward (an example of the advancing direction A of the wiping operation), a wiping operation is performed in which the blade 82 scrapes ink from the nozzle surface 14F. FIG. 7 shows the state where the blade 82 is located at the wiping operation start position. FIG. 8 shows the state where the blade 82 is located at the wiping operation end position.

[0045] [Receiving member] FIGS. 13 and 14 are perspective views showing the receiving member 84. The receiving member 84 is supported by the waste liquid tray 81 (see FIGS. 7, 8, and 10). The receiving member 84 is provided at the front end of each of the three concave portions 81U. The receiving member 84 includes a front portion 84F facing the front surface of the blade 82, a ceiling portion 84T provided rearward from the upper end of the front portion 84F, and side wall portions 84W provided rearward from both the left and right ends of the front portion 84F. That is, the receiving member 84 is formed in a box shape with the rear side and the lower side open.

[0046] When the blade 82 reaches the foremost part of the recess 81U, the blade 82 is received by the receiving member 84. At this time, the blade 82 is surrounded by the receiving member 84 from the front, above, and the left and right sides. Note that either one of the ceiling portion 84T and the side wall portion 84W may be provided.

[0047] [Cleaning liquid supply unit] Next, the cleaning liquid supply unit 40 will be described. FIG. 15 is a perspective view showing the cleaning liquid supply unit 40 and the blade unit 90. FIGS. 16 and 17 are right side views showing the cleaning liquid supply unit 40 and the blade unit 90. FIG. 18 is a perspective view showing the cleaning liquid supply unit 40. FIGS. 19 to 22 are perspective views showing cross-sections of the cleaning liquid supply unit 40 and the cleaning liquid supply source 13. The cleaning liquid supply unit 40 includes a supply member 41, a link member 42, and a transfer member 44.

[0048] [Supply member] The supply member 41 includes a base end portion 51, an intermediate portion 52, and a housing portion 53 in order from the rear. The upper surface of the supply member 41 is flat and forms a rectangle when viewed from above. The portion of the parallel surface 11P of the head base 11B behind the nozzle plate 14 faces the upper surface of the supply member 41 and also serves as a pressing portion 11D that presses down the supply member 41. Note that the pressing portion 11D may be provided as a member separate from the head base 11B.

[0049] On the left and right side surfaces of the base end portion 51, arm support portions 51L protruding leftward and rightward are provided respectively (see FIG. 18). On the left and right arm support portions 51L, arm portions 51A protruding forward are provided respectively (see FIGS. 16 to 18). Shaft portions 51S protrude from the left side surface of the left arm portion 51A and the right side surface of the right arm portion 51A. Bosses 51B are provided behind the left and right shaft portions 51S.

[0050] The thickness of the middle part 52 in the vertical direction is thinner than that of the base end part 51 (see FIGS. 16 to 18). The lower surface of the middle part 52 is flat. The lower surface of the accommodating part 53 has a first inclined surface 531 and a second inclined surface 532 provided in front of the first inclined surface 531. The first inclined surface 531 is inclined such that the front side is lower than the rear side (see FIGS. 16 and 17). The second inclined surface 532 is inclined such that the front side is higher than the rear side. The first inclined surface 531 is continuous with the lower surface of the middle part 52. Therefore, a wider space (hereinafter referred to as a non-contact space 52U) is formed below the middle part 52 compared to below the accommodating part 53.

[0051] The accommodating part 53 has a hollow structure having an accommodating space 53V for accommodating a cleaning liquid (see FIGS. 16 and 17). It is desirable that a cleaning liquid holding member 53H (see FIGS. 21 and 22) for holding the cleaning liquid, such as a net-like member or a porous member, is provided in the accommodating space 53V. An inlet 53N (see FIGS. 15, 21, and 22) for taking in the cleaning liquid is provided on the upper surface of the accommodating part 53. An outlet 53E (see FIGS. 16 and 17) for discharging the cleaning liquid is provided on the lower surface of the accommodating part 53. The thickness in the vertical direction of the front end part of the accommodating part 53 (the distance from the front end part of the second inclined surface 532 to the upper surface) is slightly larger than the distance from the lower surface of the head base 11B to the nozzle surface 14F.

[0052] [Link member] The link members 42 are provided on the left and right of the supply member 41 (see FIGS. 15 to 18). The lower parts of the left and right link members 42 are connected using a shaft 42S (see FIG. 18) having a longitudinal direction in the left-right direction. The shaft 42S is rotatably supported by a recess 81U of the waste liquid tray 81. Specifically, in the waste liquid tray 81, cutouts 81K are formed downward from the upper end parts of the left and right side wall parts of the recess 81U (see FIGS. 19 and 20). Both left and right end parts of the shaft 42S are supported by the cutouts 81K. The link member 42 is swingable around the shaft 42S.

[0053] On the upper part of the left and right link members 42, there are provided shaft holes 42H into which the shaft portion 51S of the supply member 41 is inserted (see FIGS. 16 to 18). The shaft holes 42H are arranged in front of the shaft 42S. Behind the shaft holes 42H, there are provided long holes 42L into which the bosses 51B of the supply member 41 are inserted. The supply member 41 can swing with respect to the link member 42 within the range of the longitudinal direction of the long hole 42L around the shaft portion 51S (see FIGS. 16 and 17).

[0054] [Second biasing member] The link member 42 is provided with a second biasing member 43 (see FIG. 18). Specifically, the second biasing member 43 is a torsion coil spring and is wound around the shaft 42S. One end portion of the second biasing member 43 is engaged with the holder 92, and the other end portion is engaged with the link member 42 (see FIGS. 16 and 17). The second biasing member 43 biases the link member 42 in the clockwise direction in FIGS. 16 and 17. In other words, the second biasing member 43 biases the supply member 41 in the direction approaching the inkjet head 12. Note that the second biasing member 43 may be a leaf spring, a compression coil spring, or the like.

[0055] [Delivery member] A delivery member 44 is joined to the second inclined surface 532. The delivery member 44 has the same inclination angle as the second inclined surface 532. The delivery member 44 is a rectangular sheet-like member formed of resin or the like and has flexibility. The front end portion of the delivery member 44 protrudes forward of the front end portion of the accommodating portion 53. In the delivery member 44, a discharge port 44A is provided at a position corresponding to the discharge port 53E of the accommodating portion 53 (see FIG. 18).

[0056] [Cleaning liquid supply source] The cleaning liquid supply source 13 (see Fig. 7) supplies the cleaning liquid to the supply member 41. The cleaning liquid is a liquid mainly composed of water. The cleaning liquid supply source 13 includes a tank 13T, a pump 13P, a supply flow path 13C, and a support plate 13B. The cleaning liquid is stored in the tank 13T. The supply flow path 13C branches into three downstream of the pump 13P. The branched supply flow paths 13C are each connected to a valve 13V. The valve 13V is, for example, a check valve. The three valves 13V are each disposed above the inlet 53N of the supply member 41. The supply flow path 13C and the valve 13V are supported by the support plate 13B. The valve 13V penetrates the support plate 13B, and the outlet of the valve 13V protrudes from the lower surface of the support plate 13B.

[0057] A supply source lifting device 13L (see Fig. 7) is provided before and after the support plate 13B. The supply source lifting device 13L is composed of, for example, a cam mechanism, a ball screw, etc. The supply source lifting device 13L raises and lowers the support plate 13B between a supply position (see Fig. 23(A)) and a retracted position (see Fig. 23(B)). The supply position is the position where the outlet of the valve 13V is inserted into the inlet 53N (see Figs. 20 and 22). The retracted position is the position where the outlet of the valve 13V retracts upward from the inlet 53N (see Figs. 19 and 21).

[0058] A convex portion 13BT protruding downward is provided on the lower surface of the support plate 13B at a position corresponding to the protruding portion 91P of the protruding member 91 (see Figs. 19 to 22). Further, convex portions 13BS protruding downward are provided on the lower surface of the support plate 13B to the left and right of the valve 13V (see Figs. 19 and 20).

[0059] [Outline of the operation of the wiper unit] Next, the outline of the operation of the wiper unit 32 will be described. Fig. 24 is a plan view showing the operation of the wiper unit 32. Figs. 25 to 30 are right side views showing the operation of the wiper unit 32. Here, the outline of the operation of the wiper unit 32 will be described, and the operations of the protruding member 91 and the supply member 41 will be described later.

[0060] Hereinafter, the state shown in FIGS. 23(A) and 24(A) will be described as the initial state. In the initial state, the head unit 11 is positioned at the image forming position (see FIG. 23(A)), the cap unit 31 is positioned at the home position, the wipe unit 32 is positioned at the home position and the contact position, and the cleaning liquid supply source 13 is positioned at the supply position. The blade 82 is positioned at the wipe operation start position (see FIG. 24(A)). A predetermined amount of cleaning liquid is supplied from the cleaning liquid supply source 13 to the cleaning liquid supply unit 40. The control unit 2 executes the following processes at a predetermined timing. The predetermined timing is, for example, the timing when an increase in the viscosity of the ink in the nozzle 14N is expected, specifically, when a period in which no image forming job is executed continues for a predetermined period.

[0061] First, the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see FIG. 23(B)). Further, the control unit 2 operates the supply source lifting device 13L to raise the cleaning liquid supply source 13 to the retracted position.

[0062] Next, the control unit 2 operates the cap slide device 34 to slide the cap unit 31 to the maintenance position (see FIGS. 23(C), 24(B), and 25). At this time, since the wipe unit 32 is placed on the cap unit 31, the wipe unit 32 also slides to the maintenance position together with the cap unit 31. Next, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to the height at which the wiping operation is performed (hereinafter referred to as the wipe position) (see FIGS. 23(D) and 26).

[0063] Next, after the control unit 2 causes the inkjet head 12 to eject a predetermined amount of ink, the control unit 2 activates the carriage drive device 36 to slide the blade 82 forward along the nozzle surface 14F (see FIGS. 24(C), 27, 28, and 29). The blade 82 scrapes off the cleaning liquid F bulging from the discharge port 44A (see FIG. 27) and advances along the nozzle surface 14F (see FIGS. 28 and 29). On the nozzle surface 14F, the residual ink K is diluted by the cleaning liquid F carried by the blade 82. The waste liquid containing the residual ink K and the cleaning liquid F is scraped off by the blade 82 and falls into the recess 81U.

[0064] Next, the control unit 2 activates the head lifting device 11L to raise the head unit 11 to the retracted position (see FIGS. 23(C) and 30). Next, the control unit 2 activates the carriage drive device 36 to return the blade 82 to the wiper operation start position (see FIGS. 24(B) and 25). Next, the control unit 2 activates the cap slide device 34 to slide the cap unit 31 and the wiper unit 32 to the home position (see FIGS. 23(B) and 24(A)).

[0065] Next, the control unit 2 activates the wiper lifting device 35 to raise the wiper unit 32 to the separated position (see FIG. 23(E)). Next, the control unit 2 activates the cap slide device 34 to slide the cap unit 31 to the maintenance position (see FIGS. 23(F) and 24(D)). At this time, since the wiper unit 32 is separated from the cap unit 31, the wiper unit 32 remains in the home position, and only the cap unit 31 slides to the maintenance position.

[0066] Next, the control unit 2 activates the head lifting device 11L to lower the head unit 11 to a height at which the nozzle surface 14F contacts the cap 72 (hereinafter referred to as the cap position) (see FIG. 23(G)). In this way, the cap 72 is attached to the nozzle surface 14F.

[0067] When executing an image forming job, the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see Fig. 23(F)), operates the cap slide device 34 to slide the cap unit 31 to the home position (see Fig. 23(E)), and operates the wiper lifting device 35 to lower the wiper unit 32 to the contact position (see Fig. 23(B)). Then, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to the image forming position (see Fig. 23(A)) and executes the image forming job.

[0068] [Operations of the protruding member and the supply member] Next, the operations of the protruding member 91 and the supply member 41 will be described. Fig. 16 shows a state where the protruding member 91 and the supply member 41 are not pushed down (hereinafter referred to as the non-pushed-down state). On the other hand, Fig. 17 shows a state where the protruding member 91 is pushed down by the parallel surface 11P or the convex portion 13BT and the supply member 41 is pushed down by the push-down portion 11D or the convex portion 13BS (hereinafter referred to as the pushed-down state). The first biasing member 93 biases the protruding member 91 in the counterclockwise direction in Figs. 16 and 17. Also, the second biasing member 43 biases the link member 42 in the clockwise direction.

[0069] [Non-pushed-down state] When the wiper unit 32 is located at the home position and the cleaning liquid supply source 13 is raised to the retracted position, the non-pushed-down state is achieved (see Figs. 19, 21, 23(B), (E), (F), (G)). Also, when the wiper unit 32 is located at the maintenance position and the head unit 11 is raised to the retracted position, the non-pushed-down state is also achieved (see Fig. 23(C)).

[0070] [Pushed-down state] On the other hand, when the wiper unit 32 is located at the home position and the cleaning liquid supply source 13 is lowered to the supply position, it is in the pressed state (see FIGS. 20, 22, and 23(A)). Specifically, when the cleaning liquid supply source 13 descends from the non-pressed state (see FIGS. 16, 19, and 21) (see FIGS. 17, 20, and 22), the convex portion 13BT presses down the protruding portion 91P against the first biasing member 93, and the convex portion 13BS presses down the supply member 41 against the second biasing member 43. At this time, the discharge port of the valve 13V is inserted into the intake port 53N of the supply member 41 (see FIG. 22), and it becomes possible to supply the cleaning liquid from the cleaning liquid supply source 13 to the cleaning liquid supply unit 40.

[0071] Also, when the wiper unit 32 is located at the maintenance position and the head unit 11 is lowered to the wiper position, it is also in the pressed state (see FIG. 23(D)). When the head unit 11 descends from the non-pressed state (see FIG. 16) (see FIG. 17), the parallel surface 11P presses down the protruding portion 91P against the first biasing member 93, and the pressing portion 11D presses down the supply member 41 against the second biasing member 43.

[0072] When transitioning from the non-pressed state to the pressed state, the protruding portion 91P is pushed down, causing the blade 82 to swing in the clockwise direction. Therefore, the inclination angle β of the front surface of the blade 82 with respect to the vertical line V in the pressed state (see FIG. 17) is larger than the inclination angle α in the non-pressed state (see FIG. 16). Also, when the supply member 41 is pushed down, the link member 42 swings in the counterclockwise direction. Therefore, in the pressed state, the supply member 41 moves forward and downward compared to the non-pressed state.

[0073] Here, focusing on the tip of the blade 82, in the non-pressed state, the tip of the blade 82 is located below the first inclined surface 531 of the supply member 41. On the other hand, in the pressed state, relatively, the tip of the blade 82 moves backward and downward, and the supply member 41 moves forward and downward. However, since the tip of the blade 82 enters the non-contact space 52U below the intermediate portion 52 of the supply member 41, interference between the blade 82 and the supply member 41 is avoided.

[0074] [Wiping operation] Next, the wiping operation will be described in detail. When the head unit 11 rises to the retracted position and the wiper unit 32 slides to the maintenance position (see FIGS. 23(C), 24(B), and 25), the protruding member 91 and the supply member 41 are in the non-pressed state (see FIG. 16). At this time, the rear end face of the nozzle plate 14 and the front end face of the supply member 41 are separated from each other in the front-rear direction by a distance D (see FIG. 25). The cleaning liquid F bulges out from the discharge port 44A of the transfer member 44 (see FIG. 25). Residual ink K adheres to the nozzle surface 14F (see FIG. 25).

[0075] Next, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to the wiping position (see FIGS. 23(D) and 26). Then, since the parallel surface 11P presses down the protruding member 91 and the supply member 41, the protruding member 91 and the supply member 41 are in the pressed state (see FIG. 17). At this time, the blade 82 swings from the inclination angle α to the inclination angle β. Also, since the supply member 41 moves forward, the distance between the front end face of the supply member 41 and the rear end face of the nozzle plate 14 is reduced. At this time, the front end face of the supply member 41 and the rear end face of the nozzle plate 14 may come into contact with each other. Further, the transfer member 44 moves below the nozzle surface 14F, and at least the front end portion of the upper surface of the transfer member 44 comes into contact with the nozzle surface 14F, so that the step between the second inclined surface 532 and the nozzle surface 14F is eliminated.

[0076] Next, the control unit 2 discharges a predetermined amount of ink from the inkjet head 12. By this operation, the ink with increased viscosity is discharged from the nozzle 14N. Next, the control unit 2 operates the carriage driving device 36 to slide the blade 82 forward along the nozzle surface 14F (see FIG. 24(C)). The blade 82 scrapes the cleaning liquid F bulging out from the discharge port 44A (see FIG. 27), moves along the lower surface of the transfer member 44 to the nozzle surface 14F, and then advances along the nozzle surface 14F (see FIG. 28). In FIGS. 27 and 28, the tip of the blade 82 overlaps the supply member 41 and the nozzle plate 14, but actually, the tip of the blade 82 is bent backward.

[0077] When the blade 82 advances along the nozzle surface 14F, since the blade 82 advances in a state where the protruding member 91 is in contact with the parallel surface 11P, the inclination angle of the blade 82 is kept constant. Therefore, the blade 82 is pressed against the nozzle surface 14F with a constant load. Further, the blade 82 is pressed against the nozzle surface 14F mainly by the elastic force of the first biasing member 93. The elastic force of the first biasing member 93 is adjusted so as to minimize the deflection of the blade 82.

[0078] On the nozzle surface 14F, the residual ink K is diluted by the cleaning liquid F carried by the blade 82. The waste liquid containing the residual ink K and the cleaning liquid F is scraped off by the blade 82 and flows down along the front and rear surfaces of the blade 82. The waste liquid W flowing down along the rear surface of the blade 82 passes through the through hole 91A of the protruding member 91 and drops into the recess 81U (see FIG. 11). Further, the waste liquid W flowing down along the front surface of the blade 82 is collected in the center in the left - right direction along the lower edge portion of the fixing member 94 and the lower edge portion of the protruding member 91 through the front surface of the fixing member 94 and drops into the recess 81U.

[0079] In parallel with the blade 82 passing through the front end portion of the nozzle surface 14F (see FIG. 29), the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see FIG. 30). At this time, since the head base 11B also rises, the protruding member 91 and the supply member 41 return to the non - pressed state. Further, when the blade 82 is separated from the nozzle surface 14F, the deflection deformation of the blade 82 is eliminated. By this operation, the waste liquid W is discharged from the blade 82 toward the receiving member 84. The waste liquid W received by the receiving member 84 flows down along the inner surface of the receiving member 84 and drops into the recess 81U.

[0080] If the configuration for changing the inclination angle of the blade 82 (such as the protruding member 91, the holder 92, the first biasing member 93, etc.) is not provided, the blade 82 is pressed against the nozzle surface 14F solely by the elastic force due to the flexural deformation of the blade 82 itself. Therefore, when the tip of the blade 82 passes through the front end of the nozzle surface 14F, the flexure of the blade 82 is suddenly eliminated, and there is a possibility that the waste liquid W scatters. On the other hand, in the present embodiment, the flexure of the blade 82 is suppressed to a smaller amount compared to the case where the configuration for changing the inclination angle of the blade 82 is not provided. Further, since the restoration of the inclination of the blade 82 is carried out in parallel with the elimination of the flexural deformation, the waste liquid W is mainly discharged forward and received by the receiving member 84, and the scattering of the waste liquid W is suppressed.

[0081] [Modification Example] FIG. 31 is a right side view showing the behavior of the cleaning liquid during the wiping operation in the above embodiment. FIG. 32 is a front view showing the behavior of the cleaning liquid during the wiping operation in the above embodiment. In the above embodiment, since the dimension in the width direction intersecting the traveling direction A of the supply member 41 is narrower than the blade 82, when the blade 82 transports the cleaning liquid F forward during the wiping operation, the cleaning liquid F pushed to both end sides in the width direction of the blade 82 is pushed up along the side surface 533 of the housing portion 53 of the supply member 41 (see FIGS. 31 and 32), and the cleaning liquid F enters the gap G1 between the supply member 41 and the nozzle plate 14 and the gap G2 between the nozzle surface 14F and the transfer member 44. When the wiping operation is completed and the inkjet head 12 rises, a part of the cleaning liquid F that has entered the gaps G1 and G2 may remain on the nozzle plate 14 and fall onto the sheet during image formation. Therefore, the supply member 41 according to this modification example is configured as follows.

[0082] FIG. 33 is a perspective view showing the supply member 41 according to this modification example. FIG. 34 is a right side view showing the supply member 41 according to this modification example. FIG. 35 is a front view showing the supply member 41 according to this modification example. Hereinafter, differences from the supply member 41 of the above embodiment will be described.

[0083] The transfer member 44 includes a bottom portion 44B and side portions 44W. The bottom portion 44B is provided along the lower surface (second inclined surface 532) of the supply member 41 and contacts the nozzle surface 14F when the inkjet head 12 descends. The bottom portion 44B covers the entire area of the second inclined surface 532 in the left-right direction. The side portions 44W are provided upward from both left and right end portions of the bottom portion 44B. The side portions 44W are provided along the side surface 533 in the width direction of the supply member 41 and block the gap G1 between the nozzle plate 14 and the supply member 41 when the inkjet head 12 descends. Further, the side portions 44W block the gap G2 between the bottom portion 44B and the nozzle surface 14F when the inkjet head 12 descends. The bottom portion 44B of the transfer member 44 is inclined such that the tip side is higher. The transfer member 44 has flexibility.

[0084] The side portions 44W protrude forward of the front end portion of the housing portion 53. The front end portion of the side portions 44W may protrude to the same position as the front end portion of the bottom portion 44B, but at least it may be on the front side of the rear end portion of the nozzle plate 14 when the inkjet head 12 descends. With this configuration, the gap G1 between the nozzle plate 14 and the supply member 41 is blocked by the side portions 44W when the inkjet head 12 descends.

[0085] According to the inkjet recording apparatus 1 according to this modified example described above, an inkjet head 12 having a nozzle plate 14, a head lifting device 11L for lifting and lowering the inkjet head 12, a blade 82 that performs a wiping operation along the nozzle surface 14F of the nozzle plate 14, and a supply member 41 provided on the rear side of the wiping operation progress direction A with respect to the nozzle plate 14 and having a width direction dimension intersecting the progress direction A narrower than that of the blade 82 and supplying the cleaning liquid F to the blade 82 by contact with the tip of the blade 82, and a delivery member 44 protruding forward in the progress direction A from the supply member 41. The delivery member 44 is provided along the lower surface of the supply member 41 and includes a bottom portion 44B that contacts the nozzle surface 14F when the inkjet head 12 descends, and a side portion 44W provided along the side surface 533 in the width direction of the supply member 41 and closing the gap G1 between the nozzle plate 14 and the supply member 41 when the inkjet head 12 descends. According to this configuration, since the gap G1 between the supply member 41 and the nozzle plate 14 is closed by the side portion 44W of the delivery member 44, it is possible to prevent the cleaning liquid F from entering the gap G1 between the supply member 41 and the nozzle plate 14.

[0086] Also, according to the inkjet recording apparatus 1 according to this modified example, the side portion 44W of the delivery member 44 closes the gap G2 between the bottom portion 44B and the nozzle surface 14F when the inkjet head 12 descends. According to this configuration, it is possible to prevent the cleaning liquid F from entering the gap G2 between the delivery member 44 and the nozzle surface 14F.

[0087] Also, according to the inkjet recording apparatus 1 according to this modified example, the bottom portion 44B of the delivery member 44 is inclined so that the tip side is higher. According to this configuration, since the tip portion of the delivery member 44 is in close contact with the nozzle surface 14F, the cleaning liquid F can be smoothly delivered from the supply member 41 to the nozzle surface 14F.

[0088] Also, according to the inkjet recording apparatus 1 according to this modification example, the delivery member 44 has flexibility. According to this configuration, damage to the nozzle surface 14F due to contact with the delivery member 44 can be suppressed. Also, the adhesion of the delivery member 44 to the nozzle surface 14F can be improved.

Explanation of Signs

[0089] 11L Head lifting device 12 Inkjet head 14 Nozzle plate 14F Nozzle surface 41 Supply member 44 Delivery member 44B Bottom 44W Side 82 Blade

Claims

1. An inkjet head having a nozzle plate, A head lifting device for lifting and lowering the inkjet head, A blade that performs a wiping operation along the nozzle surface of the nozzle plate, A supply member that is provided on the rear side in the advancing direction of the wiping operation with respect to the nozzle plate, has a dimension in the width direction that intersects the advancing direction and is narrower than the blade, and supplies a cleaning liquid to the blade by contact with the tip of the blade, A delivery member that protrudes forward in the advancing direction from the supply member, and is provided with: The delivery member is A bottom portion provided along the lower surface of the supply member and contacting the nozzle surface when the inkjet head descends, A side portion provided along the side surface in the width direction of the supply member and closing the gap between the nozzle plate and the supply member when the inkjet head descends. An inkjet recording apparatus characterized by comprising.

2. The inkjet recording apparatus according to claim 1, wherein the side portion of the delivery member closes a gap between the bottom portion and the nozzle surface when the inkjet head descends.

3. The inkjet recording apparatus according to claim 1 or 2, wherein the bottom portion of the delivery member is inclined so that the tip side is higher.

4. The inkjet recording apparatus according to claim 3, wherein the delivery member has flexibility.

Images