Inkjet recording apparatus

Abstract

An inkjet recording apparatus is provided. The inkjet recording apparatus has a holding member, a blade, and a force applying member. The holding member faces a nozzle face of an inkjet head and moves toward a prescribed traveling direction along the nozzle face. The blade is provided to the holding member and swings around an axis that intersects the traveling direction. The force applying member is provided to the holding member and applies a force to the blade toward a direction in which a tip end portion of the blade is pressed against the nozzle face. Accordingly, the blade is pressed against the nozzle face with a proper load.

Description

Technical Field

[0001] This invention relates to an inkjet recording device. Background Technology

[0002] In inkjet recording devices, it is believed that during periods when no image forming task is being performed, water evaporates from the ink inside the nozzles of the printhead, causing the nozzles to become clogged due to increased ink viscosity. Therefore, a purging process is performed to expel ink from the nozzles to the cover to prevent clogging. However, if ink residue remains on the nozzle surface, there is a problem that ink may fall onto the sheet during image forming tasks or adhere to the nozzle surface. Therefore, techniques for removing ink residue from the nozzle surface are being researched. For example, a structure is being developed that removes ink adhering to the nozzle surface by sliding a doctor blade in contact with the nozzle surface in a predetermined direction.

[0003] Furthermore, the nozzle surface is covered by a highly waterproof membrane. If the load applied to the nozzle surface by the doctor blade is too great, the waterproof membrane will be scraped off. Therefore, the load on the doctor blade needs to be optimized. However, in the prior art, the load is applied by the deflection of the doctor blade, thus the range of load adjustment is narrow. In addition, when an inkjet recording device has multiple inkjet heads, it has a doctor blade with the same number of inkjet heads. However, due to dimensional errors or assembly errors of components, deviations in positioning accuracy during lifting and lowering, etc., it is not easy to apply an equal load to all doctor blades.

[0004] To address this issue, in structures where multiple doctor blades are fixed to a rotating shaft and their angles are adjusted uniformly via gears, individual angle adjustments corresponding to the inkjet head are not possible. Furthermore, the need for gear control complicates the structure. Additionally, in structures where a swingably supported doctor blade is pressed against the nozzle surface by a spring, the problem of existing structures relying on doctor blade deflection is not solved because the blade's flexing deformation is limited to a predetermined range. Moreover, when changing the doctor blade angle by moving the position of the doctor blade's support shaft, the doctor blade angle may become unstable because the support shaft is not fixed. Summary of the Invention

[0005] In view of the above, the object of the present invention is to provide an inkjet recording apparatus capable of pressing a doctor blade against the nozzle surface with an appropriate load.

[0006] The inkjet recording apparatus of the present invention includes a retainer, a doctor blade, and a force-applying member. The retainer faces the nozzle face of the inkjet head and moves in a predetermined direction of travel along the nozzle face. The doctor blade is disposed on the retainer and oscillates about an axis intersecting the direction of travel. The force-applying member is disposed on the retainer and applies force to the doctor blade in a direction that pushes the tip of the doctor blade towards the nozzle face. Attached Figure Description

[0007] Figure 1 This is a schematic front view of the interior of an inkjet recording apparatus according to an embodiment of the present invention.

[0008] Figure 2 This is a top view showing an imaging unit according to an embodiment of the present invention.

[0009] Figure 3 This is a cross-sectional view of an imaging unit according to an embodiment of the present invention.

[0010] Figure 4 This is a schematic diagram illustrating the ink supply path according to one embodiment of the present invention.

[0011] Figure 5 This is a cross-sectional view showing an inkjet head according to an embodiment of the present invention.

[0012] Figure 6 This is a perspective view showing a maintenance device according to an embodiment of the present invention.

[0013] Figure 7 This is a perspective view showing the state in which the cover unit according to one embodiment of the present invention is moved to the right.

[0014] Figure 8 This is a perspective view showing the state in which the wiping unit and the cover unit according to an embodiment of the present invention are moved to the right.

[0015] Figure 9 This is a perspective view showing a wiping unit according to an embodiment of the present invention.

[0016] Figure 10 This is a perspective view showing a wiping unit according to an embodiment of the present invention.

[0017] Figure 11 This is a perspective view showing a scraper unit according to an embodiment of the present invention.

[0018] Figure 12 This is a perspective view showing a cross-section of a scraper unit according to an embodiment of the present invention.

[0019] Figure 13 This is a perspective view showing a protruding component according to an embodiment of the present invention.

[0020] Figure 14 This is a perspective view showing a protruding component according to an embodiment of the present invention.

[0021] Figure 15This is a cross-sectional view showing the operation of the maintenance device and head unit according to an embodiment of the present invention.

[0022] Figure 16 This is a cross-sectional view showing the operation of the maintenance device and head unit according to an embodiment of the present invention.

[0023] Figure 17 This is a cross-sectional view showing the operation of the maintenance device and head unit according to an embodiment of the present invention.

[0024] Figure 18 This is a cross-sectional view showing the operation of the maintenance device and head unit according to an embodiment of the present invention.

[0025] Figure 19 This is a cross-sectional view showing the operation of the maintenance device and head unit according to an embodiment of the present invention.

[0026] Figure 20 This is a cross-sectional view showing the operation of the maintenance device and head unit according to an embodiment of the present invention.

[0027] Figure 21 This is a side view schematically illustrating the operation of a scraper unit according to an embodiment of the present invention.

[0028] Figure 22 This is a side view schematically illustrating the operation of a scraper unit according to an embodiment of the present invention.

[0029] Figure 23 This is a side view schematically illustrating the operation of a scraper unit according to an embodiment of the present invention.

[0030] Figure 24 This is a side view schematically illustrating the operation of a scraper unit according to an embodiment of the present invention.

[0031] Figure 25 This is a side view schematically illustrating the operation of a scraper unit according to an embodiment of the present invention. Detailed Implementation

[0032] Below, refer to the appendix. Figure 1 The inkjet recording apparatus 1 according to one embodiment of the present invention will be described below.

[0033] First, the overall structure of the inkjet recording device 1 will be explained. Figure 1 This is a schematic front view showing the interior of the inkjet recording device 1. Figure 2 This is a top view of imaging unit 6. Figure 3 This is a cross-sectional view representing imaging unit 6. Figure 4 This is a schematic diagram showing the ink supply path 60. Figure 5This is a cross-sectional view showing the inkjet head 12. The following will... Figure 1 The front side of the paper is designated as the main viewing side (front side) of the inkjet recording device 1, and the left and right orientations are explained based on the direction from which the inkjet recording device 1 is viewed from the main viewing side. In each figure, U, Lo, L, R, Fr, and Rr represent up, down, left, right, front, and back, respectively.

[0034] Inkjet recording device 1 (reference) Figure 1 The device has a rectangular outer casing 3. A paper feed cassette 4 and a paper feed roller 5 are located in the lower part of the outer casing 3. The paper feed cassette 4 holds single sheets of paper S, such as plain paper or coated paper; the paper feed roller 5 feeds the sheets S from the paper feed cassette 4. Above the paper feed cassette 4 is a conveying unit 7 that absorbs the sheets S and conveys them in the Y direction. Above the conveying unit 7 is an imaging unit 6 that discharges ink to form an image. In the upper left part of the outer casing 3 are a discharge roller 8 and a discharge tray 9. The discharge roller 8 discharges the sheet S with the image formed on it; the discharge tray 9 holds the discharged sheet S.

[0035] The main housing 3 has an internal conveying passage 10 that allows the paper feed roller 5 to pass through the gap between the conveying unit 7 and the imaging unit 6 to reach the discharge roller 8. The conveying passage 10 is mainly formed by plate-shaped components facing each other, separated by the gap through which the sheet S passes. A conveying roller 17 is provided on the conveying passage 10 to hold and convey the sheet S. An alignment roller 18 is provided upstream of the imaging unit 6 in the conveying direction Y.

[0036] The conveying unit 7 includes an annular conveyor belt 21, a support plate 23, and a suction unit 24. The conveyor belt 21 has multiple vent holes (not shown) and is wound around a drive roller 25 and a driven roller 22. The support plate 23 has multiple vent holes, and its upper surface contacts the inner surface of the conveyor belt 21. The suction unit 24 draws air through the vent holes of the support plate 23 and the conveyor belt 21, causing the sheet S to adhere to the conveyor belt 21. The drive roller 25 is driven counterclockwise by a drive unit (not shown) including a motor and a reduction gear, causing the conveyor belt 21 to rotate counterclockwise, and the sheet S adhered to the conveyor belt 21 is conveyed in the Y direction.

[0037] Imaging unit 6 (reference) Figure 2 , 3 The device has head units 11Y, 11Bk, 11C, and 11M (collectively referred to as head unit 11). Head unit 11 has one or more inkjet heads 12, for example, three inkjet heads 12 arranged in an alternating configuration. Ink cartridges 20Y, 20Bk, 20C, and 20M (collectively referred to as ink cartridge 20), respectively filled with yellow, black, cyan, and magenta inks, are supplied via ink supply path 60 (see reference). Figure 4 It is connected to the head units 11Y, 11Bk, 11C, and 11M.

[0038] exist Figure 4 The diagram shows an ink supply path 60 corresponding to one color of ink, but in this embodiment, since four colors of ink are used, there are actually four ink supply paths 60 for each system. The inkjet recording apparatus 1 includes: an ink cartridge mounting section 61 for mounting the ink cartridge 20; a filter 62 for filtering ink; a pump 63 for drawing ink from the ink cartridge 20 via the filter 62; and an auxiliary ink reservoir 64 for storing the ink pumped out by the pump 63. Furthermore, in... Figure 4 The figure shows one inkjet head 12, but in reality, three inkjet heads 12 belonging to one head unit 11 are connected to one auxiliary ink reservoir 64.

[0039] Inkjet head 12 (reference) Figure 5 , 6 The device has a rectangular housing 12H extending longitudinally and a nozzle plate 12P located at the bottom of the housing 12H. The nozzle plate 12P has multiple nozzles 12N arranged longitudinally and a sleeve 12S connecting to a pipe from an auxiliary ink reservoir 64. Each nozzle 12N includes a branch flow path 12B branching off from the downstream side of the sleeve 12S and an outlet 12A located on the lower surface of the nozzle plate 12P, i.e., the nozzle face 12F. A vibrating plate 12V also serves as part of the inner wall of the branch flow path 12B. A pressure element 12Z is ​​provided on the vibrating plate 12V. The pressure element 12Z can be a piezoelectric element, an electrostatic actuator, a heater, etc. A drive circuit (not shown) for driving the pressure element 12Z is ​​connected to the pressure element 12Z. The liquid level in the auxiliary ink reservoir 64 is adjusted to be slightly lower than the nozzle face 12F. By making the liquid level lower than the nozzle surface 12F, a negative pressure is generated in the nozzle 12N, forming a concave meniscus that curves upward.

[0040] Control Unit 2 (refer to) Figure 1 The control unit 2 has an arithmetic unit and a storage unit (illustrations omitted). The arithmetic unit is, for example, a CPU (Central Processing Unit). The storage unit includes storage media such as ROM (Read Only Memory), RAM (Random Access Memory), and EEPROM (Electrically Erasable Programmable Read Only Memory). The arithmetic unit performs various processes by reading and executing control programs stored in the storage unit. Furthermore, the control unit 2 can also be implemented using an integrated circuit without using software.

[0041] A display and operation unit 19 is provided on the upper part of the main body shell 3 (see reference). Figure 1The display operation unit 19 includes a display panel, a touch panel overlaid on the display panel, and a key area (not shown). The control unit 2 displays a screen indicating the operation menu or status of the inkjet recording device 1 on the display panel, and controls various parts of the inkjet recording device 1 in response to operations detected by the touch panel and the key area.

[0042] The basic image forming operation of the inkjet recording device 1 is as follows. When an image forming task is input to the inkjet recording device 1 from the display operation unit 19 or an external computer, the paper feed roller 5 feeds the sheet S from the paper feed tray 4 to the transport path 10, and the alignment roller 18, which stops rotating, corrects the skewness of the sheet S. When the alignment roller 18 feeds the sheet S to the transport unit 7 at a predetermined time, the transport unit 7 absorbs the sheet S onto the conveyor belt 21 and transports it in the Y direction. When the control unit 2 supplies image data in the form of a raster to the drive circuit synchronously with the transport of the sheet S, the drive circuit supplies an ejection signal corresponding to the grayscale of the image data to the pressure element 12Z, causing ink to be ejected from the nozzle 12N, thereby forming an image on the sheet S. The discharge roller 8 discharges the sheet S with the image formed onto the discharge tray 9.

[0043] [Maintenance Device]

[0044] Next, the structure of the maintenance device 30 will be explained. Figure 6 This is a perspective view of the maintenance device 30. Figure 7 This is a perspective view showing the state in which the cover unit 70 moves to the right. Figure 8 This is a perspective view showing the state in which the wiping unit 80 and the cover unit 70 are moved to the right.

[0045] The maintenance device 30 is positioned on the left side (downstream side of the conveying direction Y) of each head unit 11 (see reference). Figure 2 , 3 Additionally, a maintenance device 30 may be installed on the right side (upstream side in the conveying direction Y) of each head unit 11. The maintenance device 30 includes: a cover unit 70 having a cover 72 mounted on the nozzle surface 12F; a wiping unit 80 having a scraper 82 for removing ink residue from the nozzle surface 12F; and a housing 31 housing the cover unit 70 and the wiping unit 80. The housing 31 is formed as a cuboid with its length along the rear-rear direction and has an opening on the right side. The maintenance device 30 includes a cover moving mechanism (not shown) for moving the cover unit 70 in the left-right direction and a wiping moving mechanism (not shown) for moving the wiping unit 80 in the left-right direction. The cover moving mechanism and the wiping moving mechanism may be, for example, driven by a belt drive, a rack and pinion mechanism, or a feed screw.

[0046] [Cover Unit]

[0047] Cover unit 70 (reference) Figure 8The device has a frame 71 and a cover 72 disposed on top of the frame 71. The frame 71 is rectangular in shape with the longitudinal direction as its length. On the frame 71, the same number of covers 72 as the inkjet heads 12 are staggered in the same manner as the inkjet heads 12. The cover 72 has an upwardly opening recess. The recess has a size that surrounds the nozzle surface 12F of one inkjet head 12. The bottom of the recess slopes down in one direction (rear in this example). An outlet (not shown) is provided at the end of the lower side of the bottom of the recess. Waste liquid storage tank 69 (see reference) Figure 4 It is connected to the nozzle.

[0048] [Wiping Unit]

[0049] Wiping unit 80 (reference) Figure 9 The device includes: a frame 81; a carriage 83 disposed above the frame 81; a doctor blade 82 protruding upward from the carriage 83; and a carriage moving mechanism (not shown) that moves the carriage 83 in a front-to-back direction. The frame 81 is formed as a rectangle with the front-to-back direction as its length. On the carriage 83, the same number of doctor blades 82 as the inkjet heads 12 are staggered in the same manner as the inkjet heads 12.

[0050] [Lifting Mechanism]

[0051] The inkjet recording apparatus 1 includes a lifting mechanism (not shown) for raising and lowering the head unit 11. The lifting mechanism may be, for example, a belt drive, a rack and pinion mechanism, or a feed screw. The lifting mechanism raises and lowers the head unit 11 between an image forming position and a retracted position above the image forming position during image forming. In the image forming position, the head unit 11 is positioned such that the distance between the conveyor belt 21 and the nozzle surface 12F is a predetermined distance. In the retracted position, a space is formed between the conveyor belt 21 and the nozzle surface 12F, allowing the cover unit 70 and the wiping unit 80 to move.

[0052] [Cleaning Fluid Supply Department]

[0053] The inkjet head 12 has a cleaning fluid supply section 13 that supplies cleaning fluid to the nozzle surface 12F (see reference). Figure 4 , 5The cleaning fluid supply unit 13 includes a cleaning fluid storage tank (not shown), a pump (not shown), an auxiliary cleaning fluid storage tank 13T, and a connecting component 13C. The cleaning fluid storage tank stores a cleaning fluid primarily composed of water. The pump is connected to the bottom of the auxiliary cleaning fluid storage tank 13T, supplying cleaning fluid from the main cleaning fluid storage tank to the auxiliary cleaning fluid storage tank 13T. The connecting component 13C is located behind the nozzle plate 12P. The connecting component 13C has a sleeve 13S for connecting a pipe from the auxiliary cleaning fluid storage tank 13T. A cleaning fluid supply port 13A is provided at the bottom of the connecting component 13C. The liquid level in the auxiliary cleaning fluid storage tank 13T is adjusted to be slightly higher than the bottom surface of the connecting component 13C. By making the liquid level higher than the bottom surface, positive pressure is generated in the cleaning fluid supply port 13A, forming a downwardly bulging convex meniscus.

[0054] Next, the wiping unit 80 will be described in detail. Figure 9 , 10 This is a three-dimensional view representing the wiping unit 80. Figure 11 This is a three-dimensional view representing scraper unit 90. Figure 12 This is a perspective view showing a cross-section of the wiping unit 80. Figure 13 This is a perspective view showing the protruding component 91 and the scraper 82. Figure 14 This is a perspective view showing the protruding component 91.

[0055] The inkjet recording apparatus 1 according to this embodiment includes: a retainer 92 facing the nozzle surface 12F of the inkjet head 12 and moving in a predetermined travel direction D along the nozzle surface 12F; a doctor blade 82 disposed on the retainer 92 and pivoting about an axis intersecting the travel direction D; and a force-applying member 93 disposed on the retainer 92 and applying force to the doctor blade 82 in a direction that pushes the tip of the doctor blade 82 toward the nozzle surface 12F. Specifically, it is described below.

[0056] Wiping unit 80 (reference) Figure 9 , 10 It has multiple (three in this embodiment) scraper units 90, a frame 81, and a carriage 83. Scraper unit 90 (refer to...) Figure 11 , 12 It has a scraper 82, a protruding part 91, a retainer 92 and a force-applying part 93.

[0057] [scraper]

[0058] Scraper 82 (reference) Figures 11 to 13 It is a flexible, plate-shaped component formed of resin or the like. The scraper 82 is held in the holder 92 with its thickness direction along the front-to-back direction. The width of the scraper 82 in the left-to-right direction is greater than or equal to the width in the left-to-right direction of the area on the nozzle surface 12F where the nozzle 12N is provided.

[0059] [Protruding Components]

[0060] Protruding component 91 (refer to) Figures 11 to 14 The protruding member 91 is integral with the scraper 82. It includes: a base 91B parallel to the scraper 82; a first bend 911 bending rearward from the upper end of the base 91B; a second bend 912 bending upward from the rear end of the first bend 911; a rearward-inclined portion 91S more rearward than the second bend 912; and a protrusion 91P protruding upward from the upper end of the rearward-inclined portion 91S. The width of the base 91B in the left-right direction is equal to the width of the scraper 82. The length of the base 91B in the vertical direction is approximately half the length of the scraper 82 in the vertical direction. The base 91B engages with the lower part of the rear surface of the scraper 82. A shaft 91H (see reference) with the left-right direction as its axis is provided on the base 91B. Figure 13 , 14 ).exist Figure 11 In this example, the scraper 82 is clamped and fixed with screws by the base 91B and the sheet metal part 94. The widths of the first bend 911 and the second bend 912 in the left-right direction are equal to the width of the base 91B.

[0061] The width of the backward-tilting portion 91S in the left-right direction is wider than the width of the doctor blade 82. A protrusion 91P is provided at both ends of the upper portion of the backward-tilting portion 91S. Furthermore, the protrusion 91P is located on the outer side of the doctor blade 82 in the left-right direction. In other words, the protrusion 91P is located on the nozzle surface 12F and on the outer side of the area where the nozzle 12N is located in the left-right direction. The protrusion 91P tilts backward at the same angle as the backward-tilting portion 91S. A through hole 91A extending downward is provided at the center of the first bend 911 in the left-right direction. At least a portion of the waste liquid W (a mixture of ink i and cleaning liquid F) flowing down the rear surface of the doctor blade 82 passes through the through hole 91A and is discharged downward.

[0062] [Retaining component]

[0063] Retainer 92 (refer to) Figure 11 , 12 The retainer 92 has a hole 92H at its lower part for inserting the shaft 91H of the protruding member 91 (see reference). Figure 11 , 12 Two wall portions 91C facing each other in the left-right direction are provided on the rear surface of the base 91B. A shaft 91H protruding to the left is provided on the left surface of the left wall portion 91C. A shaft 91H protruding to the right is provided on the right surface of the right wall portion 91C. The protruding member 91 is hinged to the retainer 92, allowing the protruding member 91 to swing relative to the retainer 92 in the front-back direction. The scraper 82 swings together with the protruding member 91. Alternatively, the shaft 91H may also be provided on the scraper 82.

[0064] The scraper 82 and the protruding part 91 are positioned in a tilted manner relative to the left and right directions, so that the waste liquid W flows in either the left or right direction. In the illustrated example, the scraper 82 is tilted so that the left end is positioned slightly behind the right end, but it can also be tilted in the opposite direction.

[0065] [Force-applying component]

[0066] Force-applying component 93 (refer to) Figure 13 , 14 For example, a torsion coil spring is wound around shaft 91H. One end of the force-applying member 93 engages with the retainer 92, and the other end engages with the protruding member 91. The force-applying member 93 is... Figure 11 , 12 A force is applied to the protruding part 91 in a counterclockwise direction. Figure 13 The force is applied to the protruding member 91 in a clockwise direction. In other words, the force-applying member 93 applies force to the scraper 82 in the direction that pushes the tip of the scraper 82 toward the nozzle surface 12F. Furthermore, the force-applying member 93 can be a leaf spring, a compression coil spring, or the like.

[0067] [frame]

[0068] Frame 81 (Reference) Figure 9 , 10 The overall shape is a cuboid with the longitudinal direction as its length. The frame 81 has three upward-opening recesses 81U. The three recesses 81U face the three inkjet heads 12 of the head unit 11. That is, the three recesses 81U include two recesses 81U arranged in the longitudinal direction and one recess 81U staggered to the left of the two recesses 81U. When viewed from above, the recesses 81U are elongated rectangles in the longitudinal direction. The length of the recess 81U in the longitudinal direction is slightly longer than the nozzle surface 12F, and the width of the recess 81U in the lateral direction is slightly wider than the nozzle surface 12F.

[0069] [Slide Cart]

[0070] Carriage 83 (reference) Figures 9 to 12 It is formed into a plate shape with the longitudinal direction as its length. A groove 81G along the longitudinal direction is provided between the left and right recesses 81U, and the slide 83 is received in the groove 81G. The longitudinal length of the slide 83 is shorter than the longitudinal length of the groove 81G. Therefore, the slide 83 can move along the groove 81G in the longitudinal direction.

[0071] Each of the three recesses 81U houses one scraper unit 90. The three scraper units 90 are coupled to the carriage 83. The three scraper units 90 are configured such that, with the carriage 83 at its rearmost position, the three scraper units 90 are located behind the nozzle surface 12F.

[0072] A drive unit (not shown) is provided on the frame 81. The drive unit may be, for example, a belt drive, a gear rack, a feed screw, etc., which causes the carriage 83 to move along the groove 81G in the front-to-back direction. The carriage 83, the groove 81G, and the drive unit constitute the carriage moving mechanism described above.

[0073] [Supporting Components]

[0074] Component 84 (refer to) Figure 9 , 10 12) It is provided at the front end of the recess 81U. The receiving member 84 is formed in the shape of a box with openings at the rear and bottom. When the scraper 82 reaches the front of the recess 81U, the scraper 82 is received in the receiving member 84. At this time, the scraper 82 is covered by the receiving member 84 from the front, top, and left and right sides.

[0075] Next, the operation of the maintenance device 30 will be explained. Figures 15 to 20 This is a cross-sectional view showing the operation of the maintenance device 30 and the head unit 11. Figures 21 to 25 This is a side view schematically showing the operation of the scraper unit 90.

[0076] Here, the parallel plane 11P is described. The inkjet head 12 consists of the head base 11B (see reference). Figure 21 The head base 11B has a through hole for inserting the nozzle plate 12P of the inkjet head 12. The lower surface of the head base 11B is a plane parallel to the nozzle surface 12F, and is therefore referred to as the parallel surface 11P. When the nozzle plate 12P is inserted into the head base 11B, the nozzle surface 12F protrudes downward from the parallel surface 11P by a few millimeters (mm), forming a step between the parallel surface 11P and the nozzle surface 12F. Furthermore, the parallel surface 11P may differ from this embodiment in addition to being parallel to the nozzle surface 12F. For example, the parallel surface 11P and the nozzle surface 12F may be at the same height. Alternatively, the parallel surface 11P may be a part of the nozzle surface 12F, that is, the left and right surfaces of the area in the nozzle surface 12F where the nozzle 12N is formed.

[0077] The following describes the state of the head unit 11 at the image forming position (refer to...). Figure 15 The following description assumes the initial state. The actions shown below are performed by the control unit 2, which controls the lifting mechanism, the cover moving mechanism, the wiping moving mechanism, and the carriage moving mechanism.

[0078] First, the control unit 2 activates the lifting mechanism, raising the head unit 11 to the retracted position (see reference). Figure 16 Next, the control unit 2 activates the cover moving mechanism, moving the cover unit 70 below the head unit 11 (see reference). Figure 17Next, the control unit 2 activates the lifting mechanism, causing the head unit 11 to descend to the height where the nozzle surface 12F contacts the cover 72 (see reference). Figure 18 Next, the control unit 2 controls the inkjet head 12 to blow ink onto the cover 72.

[0079] Next, the control unit 2 activates the lifting mechanism, raising the head unit 11 to the retracted position (see reference). Figure 17 Next, the control unit 2 activates the wiping movement mechanism, moving the wiping unit 80 to below the head unit 11 (see reference). Figure 19 At this time, in the wiping unit 80, the scraper unit 90 is located at the rearmost position (see reference). Figure 21 The doctor blade 82 is tilted backward at an angle α relative to the vertical (line segment V). α is, for example, about 5°. Ink i remains on the nozzle surface 12F.

[0080] Next, the control unit 2 activates the lifting mechanism, causing the head unit 11 to descend to a predetermined position (see reference). Figure 20 In the designated location (refer to...) Figure 22 By pushing the protrusion 91P downwards from the parallel plane 11P, the protrusion 91 and the scraper 82 swing clockwise, and the scraper 82 tilts further backward. At this time, the scraper 82 is in a posture with a backward tilt angle β (α < β) relative to the vertical. β is, for example, about 15°.

[0081] Next, the control unit 2 activates the cleaning fluid supply unit 13, causing the cleaning fluid F to bulge out from the cleaning fluid supply port 13A of the connecting member 13C (see reference). Figure 5 , 22 This causes the carriage moving mechanism to actuate, causing the scraper 82 to move forward (in one example of the specified travel direction D) (see reference). Figure 23 The doctor blade 82 scrapes cleaning fluid F from the cleaning fluid supply port 13A and then moves while scraping ink i from the nozzle surface 12F. Since the protruding member 91 moves in contact with the parallel surface 11P, the tilt angle of the doctor blade 82 changes little, allowing it to be pressed against the nozzle surface 12F with a constant load. Furthermore, because the doctor blade 82 is flexible, it undergoes slight bending deformation when pressed against the nozzle surface 12F, but the force-applying member 93 absorbs excess load, thus allowing the doctor blade 82 to be pressed against the nozzle surface 12F with an appropriate load.

[0082] As the doctor blade 82 moves, the ink i is diluted by the cleaning fluid F and falls along the doctor blade 82. Waste liquid W, a mixture of ink i and cleaning fluid F, flows down the front and rear surfaces of the doctor blade 82. The waste liquid W flowing down the rear surface of the doctor blade 82 passes through the through-hole 91A of the protruding member 91 and flows downwards. The waste liquid W falling from the doctor blade 82 and the protruding member 91 passes through the nozzle (not shown) provided in the recess 81U and falls into the cover 72.

[0083] At the end of wiping, that is, when the scraper 82 passes the front end of the nozzle face 12F (see reference). Figure 24 The control unit 2 activates the lifting mechanism, causing the head unit 11 to rise to the retracted position (see reference). Figure 19 Furthermore, as the head base 11B also rises, the protruding member 91 swings counterclockwise, and the tilt of the scraper 82 returns to angle α. Additionally, as the scraper 82 moves away from the nozzle surface 12F, the deflection deformation of the scraper 82 is eliminated. Through this action, waste liquid is discharged from the scraper to the receiving member. The waste liquid W collected by the receiving member 84 flows downward along the inner surface of the receiving member 84, passes through the spray outlet (not shown) provided in the recess 81U, and falls into the cover 72.

[0084] Assuming that the tilt of the scraper 82 is not restored, when the tip of the scraper 82 passes the front end of the nozzle surface 12F, the deflection of the scraper 82 is eliminated, which could cause the waste liquid W to be released obliquely upward from the tip of the scraper 82, colliding with the head base 11B and scattering. In contrast, in this embodiment, since the tilt of the scraper 82 is restored simultaneously with the elimination of the deflection deformation, the waste liquid W is released forward and caught by the receiving member 84, thereby suppressing the scattering of the waste liquid W.

[0085] Next, the control unit 2 activates the wiping movement mechanism to house the wiping unit 80 in the housing 31 (see reference). Figure 17 Next, the control unit 2 activates the lifting mechanism, causing the head unit 11 to descend to the height where the nozzle surface 12F contacts the cover 72 (see reference). Figure 18 ).

[0086] When image formation is being performed, the control unit 2 activates the lifting mechanism, causing the head unit 11 to rise to the retracted position (see reference). Figure 17 Next, the control unit 2 activates the cover moving mechanism to house the cover unit 70 within the outer casing 31 (see reference). Figure 16 This causes the lifting mechanism to operate, lowering the head unit 11 to the image forming position (see reference). Figure 15 ).

[0087] The inkjet recording apparatus 1 according to the above-described embodiment includes: a retainer 92 facing the nozzle surface 12F of the inkjet head 12 and moving in a predetermined travel direction D along the nozzle surface 12F; a doctor blade 82 disposed on the retainer 92 and oscillating about an axis 91H intersecting the travel direction D; and a force-applying member 93 disposed on the retainer 92 and applying force to the doctor blade 82 in a direction that pushes the tip of the doctor blade 82 toward the nozzle surface 12F. According to this structure, compared to the case where the doctor blade 82 does not oscillate, since the force-applying member 93 absorbs excess load, the doctor blade 82 can be pressed against the nozzle surface 12F with an appropriate load. Furthermore, since the force-applying member 93 is provided for each doctor blade 82, the load can be optimized for each inkjet head 12 when multiple inkjet heads 12 are provided.

[0088] Furthermore, the inkjet recording apparatus 1 according to this embodiment has a protruding member 91 integrally provided with the doctor blade 82, which protrudes rearward in the travel direction D from the shaft 91H. The doctor blade 82 is tilted rearward in the travel direction D by being pushed towards the retainer 92 by the nozzle surface 12F or a parallel surface 11P parallel to the nozzle surface 12F. With this structure, since the doctor blade 82 tilts rearward when the protruding member 91 is pressed against the nozzle surface 12F or the parallel surface 11P, the doctor blade 82 can be pressed against the nozzle surface 12F with the minimum required load. Furthermore, since the protruding member 91 moves in contact with the nozzle surface 12F or the parallel surface 11P, the change in the tilt angle of the doctor blade 82 is small, and the doctor blade 82 can be pressed against the nozzle surface 12F with a constant load.

[0089] Furthermore, in the inkjet recording apparatus 1 according to this embodiment, the parallel surface 11P is provided on the outside of the nozzle surface 12F in the width direction intersecting the travel direction D, and the protruding member 91 contacts the parallel surface 11P. With this structure, since the protruding member 91 does not contact the nozzle surface 12F, damage to the nozzle surface 12F can be prevented.

[0090] Furthermore, according to the inkjet recording apparatus 1 of this embodiment, the protruding member 91 has a through hole 91A, which discharges liquid flowing down along the doctor blade 82. With this structure, it is possible to prevent ink-containing waste liquid W removed from the nozzle surface 12F from remaining and becoming fixed to the protruding member 91. In particular, since the opening of the through hole 91A on the side for the waste liquid W to flow into is located above the shaft 91H, it is less likely to obstruct the oscillating motion caused by the drained liquid W being fixed near the shaft 91H. Moreover, it is less likely for the waste liquid W passing through the through hole 91A to come into contact with the shaft 91H. Specifically, since the path of the waste liquid W flowing through the through hole 91A and the shaft 91H are separated by the wall portion 91C, it is less likely for the waste liquid W to come into contact with the shaft 91H. It is also possible to prevent the waste liquid W from coming into contact with the shaft 91H by arranging the discharge side opening of the through hole 91A below the shaft 91H.

[0091] Furthermore, the inkjet recording apparatus 1 according to this embodiment includes a receiving member 84, which is positioned forward of the moving end position of the retaining member 92 in the traveling direction D, for receiving liquid discharged from the doctor blade 82. With this structure, the scattering of waste liquid W discharged from the doctor blade 82 can be suppressed.

[0092] Furthermore, the inkjet recording apparatus 1 according to this embodiment includes a lifting mechanism that raises or lowers the inkjet head 12 or the holder 92. This lifting mechanism separates the inkjet head 12 from the holder 92 when the wiping operation of the doctor blade 82 on the nozzle surface 12F is completed. With this structure, since the doctor blade 82 is smoothly raised at the end of wiping, the waste liquid W adhering to the doctor blade 82 can be directed towards the receiving member 84. Additionally, since the waste liquid W remaining on the doctor blade 82 is easily directed downwards, liquid residue on the doctor blade 82 is less likely to remain.

[0093] The above implementation method can be modified as follows.

[0094] In the above embodiment, an example is shown where the inkjet head 12 is separated from the holder 92 at the end of erasure. However, the step between the front end of the nozzle surface 12F and the parallel surface 11P can also be eliminated by tilting the portion of the parallel surface 11P of the head base 11B that is forward of the front end of the nozzle surface 12F (illustration omitted). According to this structure, since the doctor blade 82 is smoothly erected at the end of erasure, the waste liquid W adhering to the doctor blade 82 can also be directed towards the receiving member 84.

[0095] In addition to the structure described above, a roller (not shown) that rotates about an axis parallel to shaft 91H can also be provided. This structure reduces the frictional resistance between the protruding member 91 and the parallel surface 11P.

Claims

1. An inkjet recording device, characterized in that, It has a retainer, a scraper, a force-applying component, and a protruding component, among which, The retainer faces the nozzle face of the inkjet head and moves in a predetermined direction of travel along the nozzle face; The scraper is flexible, is disposed in the retainer, and oscillates about an axis that intersects the direction of travel; The force-applying component is disposed on the retainer and applies force to the scraper in the direction of pushing the tip of the scraper toward the nozzle surface, so that the scraper swings in a predetermined posture; The protruding component is integrally formed with the scraper and protrudes rearward beyond the axis of travel. By being pushed towards the retainer by the nozzle surface or a parallel surface parallel to the nozzle surface, the scraper is tilted rearward in the direction of travel. When the protruding member is pushed by the nozzle surface or a parallel surface parallel to the nozzle surface towards the retainer, the scraper swings in a tilting posture that is more inclined than the predetermined posture. Subsequently, as the retainer moves in the direction of travel, the protruding member moves in contact with the nozzle surface or the parallel surface, and the scraper undergoes flexural deformation by being pushed by the nozzle surface, accompanied by elastic deformation of the force-applying member.

2. The inkjet recording device according to claim 1, characterized in that, The parallel surface is positioned on the outer side of the nozzle surface in a width direction intersecting the direction of travel. The protruding component is in contact with the parallel surface.

3. The inkjet recording device according to claim 2, characterized in that, During the movement of the retainer along the travel direction, the protruding member moves in contact with the parallel surface.

4. The inkjet recording device according to claim 2, characterized in that, The protruding parts are located on both outer sides in the width direction of the scraper.

5. The inkjet recording device according to claim 1, characterized in that, The protruding component has a through hole for allowing at least a portion of the liquid flowing down the scraper to pass through it.

6. The inkjet recording apparatus according to claim 1, characterized in that, It has a receiving component, which is positioned forward of the direction of travel than the end position of the movement of the retainer, for receiving liquid discharged from the scraper.

7. The inkjet recording apparatus according to claim 1, characterized in that, It has a lifting mechanism that allows the inkjet head or the holder to be raised or lowered. The lifting mechanism separates the inkjet head from the holder when the wiping of the nozzle surface by the scraper ends.

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