Maintenance device and inkjet recording apparatus

Abstract

The invention provides a maintenance device and an ink jet recording apparatus. The purpose of the present invention is to prevent direct contact between humidified air and a nozzle surface. The maintenance device includes a cover and a suppression member. The cover includes an air inlet and an air outlet, and is mounted on a nozzle surface of the inkjet head. And a suppression member that faces the intake port and is provided between the intake port and the nozzle surface, the suppression member being separated from the intake port and the nozzle surface.

Description

Technical Field

[0001] The present invention relates to a maintenance device and an inkjet recording device, wherein the maintenance device performs maintenance on an inkjet head. Background Art

[0002] In an inkjet recording device using water-based ink, when printing is not performed, water evaporates from the ink in the nozzle, the viscosity increases, and ejection failure and clogging may occur. Therefore, the prior art has studied the suppression of the evaporation of water from the ink in the nozzle. For example, there is a device that supplies humidified air into a cap covering the ejection surface (nozzle surface) of the head. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] However, in the structure of the prior art, the humidified air directly contacts the nozzle surface. In this case, condensation may occur on the nozzle surface, and the ink may be pulled by the condensation and leak out of the nozzle. In addition, the humidified air is supplied from the air inlet provided in the cover. As the distance from the air inlet increases, the humidified air is difficult to reach the nozzle surface, and the viscosity of the ink increases. Therefore, there are problems such as uneven discharge performance and deviation of the image density from the image data.

[0005] In view of the above problems, an object of the present invention is to first prevent humidified air from directly contacting the nozzle surface, and further preferably to improve the uniformity of humidification of the nozzle surface.

[0006] (II) Technical solution

[0007] The maintenance device of the present invention comprises: a cover, which includes an air inlet and an exhaust port and is installed on the nozzle surface of the inkjet head; and a suppression component, which is opposite to the air inlet and is arranged between the air inlet and the nozzle surface, separated from the air inlet and separated from the nozzle surface.

[0008] Furthermore, the inkjet recording device of the present invention includes an inkjet head and the maintenance device.

[0009] (III) Beneficial effects

[0010] According to the present invention, it is possible to prevent the humidified air from directly contacting the nozzle surface and improve the uniformity of humidification of the nozzle surface.

[0011] Other objects of the present invention and specific advantages that can be obtained by the present invention will become more apparent from the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a perspective view showing the appearance of the image forming system according to the first embodiment of the present invention.

[0013] Figure 2 It is a front view schematically showing the internal structure of the inkjet recording apparatus according to the first embodiment of the present invention.

[0014] Figure 3 It is a front view schematically showing the head unit and the maintenance device according to the first embodiment of the present invention.

[0015] Figure 4 It is a plan view schematically showing the head unit and the wiping unit according to the first embodiment of the present invention.

[0016] Figure 5 It is a plan view schematically showing the cover unit according to the first embodiment of the present invention.

[0017] Figure 6 It is a cross-sectional view showing an ink jet head according to a first embodiment of the present invention.

[0018] Fig. 7A It is a front view showing the operation of the maintenance device according to the first embodiment of the present invention.

[0019] Figure 7B It is a front view showing the operation of the maintenance device according to the first embodiment of the present invention.

[0020] Figure 7C It is a front view showing the operation of the maintenance device according to the first embodiment of the present invention.

[0021] Fig.7D It is a front view showing the operation of the maintenance device according to the first embodiment of the present invention.

[0022] Fig. 7E It is a front view showing the operation of the maintenance device according to the first embodiment of the present invention.

[0023] Figure 7F It is a front view showing the operation of the maintenance device according to the first embodiment of the present invention.

[0024] Figure 7G It is a front view showing the operation of the maintenance device according to the first embodiment of the present invention.

[0025] Figure 8 It is a perspective view showing a cover unit according to the first embodiment of the present invention.

[0026] Fig. 9 It is a plan view showing the cover unit according to the first embodiment of the present invention.

[0027] Fig.10 Yes means Fig. 9 Cross-sectional view of section X-X.

[0028] Fig.11It is an exploded view showing the cover unit according to the first embodiment of the present invention.

[0029] Fig.12 It is a diagram showing the flow of air and humidified air in the cover unit according to the first embodiment of the present invention.

[0030] Fig.13 It is a plan view showing the positions of the humidification tank and the recovery tank according to the first embodiment of the present invention.

[0031] Fig.14 This is a cross-sectional view showing the flow of humidified air in the cover according to the first embodiment of the present invention.

[0032] Fig.15 It is a cross-sectional view showing a cover unit including a suppression member according to the first embodiment of the present invention.

[0033] Fig.16 It is a plan view showing a cover including a suppressing member according to the first embodiment of the present invention.

[0034] Fig.17 It is a cross-sectional view showing a cover unit including a suppression member according to a second embodiment of the present invention.

[0035] Fig.18 It is a plan view showing a cover including a suppressing member according to a second embodiment of the present invention.

[0036] Fig.19 It is a plan view showing a cover including a suppressing member according to a third embodiment of the present invention.

[0037] Fig. 20 It is a plan view showing a cover including a suppressing member according to a fourth embodiment of the present invention.

[0038] Fig.21 It is a plan view showing a cover including a suppressing member according to a fifth embodiment of the present invention.

[0039] Fig. 22 It is a plan view showing a cover including a suppressing member according to a sixth embodiment of the present invention.

[0040] Fig.23 It is a plan view showing a cover including a suppressing member according to a seventh embodiment of the present invention.

[0041] Fig.24 Yes means Fig. 22 Cross-sectional view of section XXIV-XXIV.

[0042] Fig.25 It is a cross-sectional view showing a first modified example of the sixth embodiment of the present invention.

[0043] Fig.26It is a cross-sectional view showing a second modified example of the sixth embodiment of the present invention.

[0044] Fig. 27 It is a cross-sectional view showing a cover unit including a suppression member according to an eighth embodiment of the present invention.

[0045] Fig.28 It is a plan view showing a cover including a suppression member according to an eighth embodiment. DETAILED DESCRIPTION

[0046] [First embodiment]

[0047] Hereinafter, an inkjet recording apparatus 1 according to a first embodiment of the present invention will be described with reference to the drawings.

[0048] Figure 1 It is a perspective view showing the appearance of the image forming system 100 . Figure 2 It is a front view schematically showing the internal structure of the inkjet recording device 1 . Figure 3 It is a front view schematically showing the head unit 11 and the maintenance device 30 . Figure 4 It is a plan view schematically showing the head unit 11 and the wiping unit 32 . Figure 5 It is a plan view schematically showing the cover unit 31 . Figure 6 It is a cross-sectional view showing the inkjet head 12 . FIG. 7A to FIG. 7G 30 is a front view showing the operation of the maintenance device 30. Figure 2 The front side of the paper in the figure is set as the front side (front side) of the inkjet recording device 1, and the left and right direction is described based on the direction of viewing the inkjet recording device 1 from the front. In each figure, U, Lo, L, R, Fr, and Rr represent up, down, left, right, front, and back, respectively.

[0049] Image forming system 100 (see Figure 1 ) includes: a paper supply device 110, an inkjet recording device 1, a drying device 120, and a post-processing device 130. The paper supply device 110 stores thousands of sheets and supplies the sheets to the inkjet recording device 1. The inkjet recording device 1 forms an image on the sheet by inkjet method. The drying device 120 heats the sheet conveyed from the inkjet recording device 1 to dry the ink. The post-processing device 130 performs post-processing such as punching, binding, and folding on the sheet conveyed from the drying device 120.

[0050] Inkjet recording device 1 (refer to Figure 2) is provided with a main body cover 3 in the shape of a rectangular parallelepiped. A conveying unit 7 is provided in the central part inside the main body cover 3. The conveying unit 7 absorbs the sheet and conveys it in the Y direction. An imaging unit 6 is provided above the conveying unit 7. The imaging unit 6 ejects ink to form an image. A paper supply port 8 is provided on the right side of the main body cover 3. The paper supply port 8 introduces the sheet from the paper supply device 110. A discharge port 9 is provided on the left side of the main body cover 3. The discharge port 9 discharges the sheet with the image formed thereon to the drying device 120. A conveying path 10 is provided inside the main body cover 3. The conveying path 10 reaches the discharge port 9 from the paper supply port 8 through the gap between the conveying unit 7 and the imaging unit 6. A positioning roller 18 is provided on the upstream side of the conveying unit 7 in the conveying direction Y.

[0051] The conveying unit 7 includes an endless conveyor belt 21 and a suction unit 24. The conveyor belt 21 has a plurality of vents (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 plurality of vents (not shown) and is in contact with the inner surface of the conveyor belt 21. The suction unit 24 sucks air through the vents of the conveyor belt 21 and the vents of the suction unit 24, so that the sheet is adsorbed to the conveyor belt 21. The driving roller 25 is driven counterclockwise by a driving unit (not shown) including a motor and a reduction gear, so that the conveyor belt 21 rotates counterclockwise, and the sheet adsorbed to the conveyor belt 21 is conveyed in the Y direction.

[0052] The imaging unit 6 includes a plurality of (four in this embodiment) head units 11. The head unit 11 (see Figure 3 , Figure 4 ) has one or more (three in this embodiment) inkjet heads 12. In this embodiment, the head unit 11 for black ink is connected to an ink container 20 filled with black ink. The head unit 11 for cyan ink is connected to an ink container 20 filled with cyan ink. The head unit 11 for magenta ink is connected to an ink container 20 filled with magenta ink. The head unit 11 for yellow ink is connected to an ink container 20 filled with yellow ink.

[0053] Inkjet head 12 (see Figure 6) is provided with: a rectangular parallelepiped cover 12H with the front-to-back direction as the long side direction, a nozzle plate 14 provided at the bottom of the cover 12H, and an interface 12S connected to the piping for supplying ink. The nozzle plate 14 is provided with: a plurality of nozzles 14N arranged in the front-to-back direction. The nozzle 14N includes: a branch flow path 14B branched from the downstream side of the interface 12S, and a discharge port 14A provided on the lower surface of the nozzle plate 14, i.e., the nozzle surface 14F. The vibration plate 14V also serves as a part of the inner wall of the branch flow path 14B. A pressure element 14Z is provided on the vibration plate 14V. As the pressure element 14Z, a piezoelectric element, an electrostatic actuator, a heater, etc. can be used. A driving circuit 12D is connected to the pressure element 14Z, and the driving circuit 12D drives the pressure element 14Z.

[0054] Control unit 2 (refer to Figure 2 ) has: a computing unit and a storage unit (not shown). The computing 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 computing unit reads out and executes the control program stored in the storage unit to perform various processes. In addition, the control unit 2 can also be implemented by an integrated circuit that does not use software.

[0055] A display operation unit 19 (see Figure 1 , Figure 2 ). The display operation unit 19 includes: a display panel, a touch panel stacked on the display panel, and a keyboard (not shown). The control unit 2 causes the display panel to display the following screen, that is, the screen displays the operation menu, status, etc. of the inkjet recording device 1, and the control unit 2 controls each part of the inkjet recording device 1 according to the operation detected by the touch panel and the keyboard.

[0056] The basic image forming operation of the inkjet recording device 1 is described 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 device 110 feeds a sheet to the conveying path 10 through the paper feed port 8, and the registration roller 18 stops rotating to correct the skew of the sheet. When the registration roller 18 feeds the sheet to the conveying unit 7 at a predetermined time, the conveying unit 7 adsorbs the sheet to the conveying belt 21 and conveys it in the Y direction. Ink is ejected from the inkjet head 12 to the sheet to form an image. The sheet on which the image is formed is discharged to the drying device 120 through the discharge port 9.

[0057] [Maintenance device]

[0058] Next, the maintenance device 30 will be described. Since the four head units 11 have the same structure and the four maintenance devices 30 have the same structure, one head unit 11 and one maintenance device 30 provided on the right thereof will be described below.

[0059] The head unit 11 includes a head base 11B (see Figure 3 , Figure 4 ). Three inkjet heads 12 are arranged in a staggered manner on the head base 11B.

[0060] Maintenance device 30 (see Figure 3 ) is provided on the side (right side in the present embodiment) of the head unit 11 . The maintenance device 30 includes a cap unit 31 and a wiping unit 32 .

[0061] [Cover unit]

[0062] Cover unit 31 (see Figure 3 , 5 ) has the same number of caps 72 as the inkjet heads 12 of the head unit 11 (three in this embodiment). The three caps 72 are arranged in a staggered manner like the inkjet heads 12 and supported by the frame 71. Two caps 72 are arranged in the front-to-back direction at a portion of the frame 71 that is closer to the right side than the center in the left-right direction, and one cap 72 is arranged on the left side of them. The left cap 72 is arranged at the middle position in the front-to-back direction of the two right caps 72.

[0063] [Wipe unit]

[0064] Wiping unit 32 (refer to Figure 3 , Figure 4 ) comprises: a waste liquid tray 81 and a cleaning component 82. The waste liquid tray 81 comprises: the same number of recesses 81U as the inkjet heads 12 possessed by the head unit 11. The plurality of recesses 81U are arranged in a staggered manner in the same manner as the inkjet heads 12. A cleaning component 82 is provided in each recess 81U. The cleaning component 82 is, for example, a scraper. The waste liquid tray 81 comprises: a driving unit (not shown) for sliding the cleaning component 82 along the nozzle surface 14F. The waste liquid tray 81 is placed on a plurality of covers 72. In other words, the wiping unit 32 is placed on the cover unit 31. The head unit 11 is provided with: a cleaning liquid supply device 13 (refer to Figure 6 ).

[0065] [Head lifting device]

[0066] Head lifting device 11L (refer to Figure 4) are provided in front 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 the image forming position and the retreat position. Image forming position (refer to Fig. 7A ) is a position where the distance between the conveying path 10 (the upper surface of the conveying belt 21) for conveying the sheet and the nozzle surface 14F is a predetermined distance suitable for image formation. The image forming position is the lower limit position of the lifting range of the head unit 11 by the head lifting device 11L. The retreat position (refer to Figure 7B ) is a position where the head unit 11 and the wiping unit 32 do not interfere with each other when the cover unit 31 and the wiping unit 32 are slid by the cover sliding device 34 described later. The retracted position is the upper limit position of the lifting range of the head unit 11.

[0067] [Cover sliding device]

[0068] Cover sliding device 34 (refer to Figure 5 ) are provided at the front and rear of the frame 71 of the cover unit 31. The cover slide device 34 is composed of, for example, a ball screw, a belt drive device, etc. The cover slide device 34 slides the cover unit 31 to the home position and the maintenance position. The home position (refer to Fig. 7A ) is located to the right of the head unit 11 at the image forming position. Figure 7F ) is a position below the head unit 11 located in the retracted position.

[0069] [Wipe lift device]

[0070] Wiping lifting device 35 (refer to Figure 4 ) are provided in front and behind the waste liquid tray 81 of the wiping unit 32. The wiping lifting device 35 is composed of, for example, a ball screw, a belt drive device, etc. (not shown). The wiping lifting device 35 lifts the wiping unit 32 to the following position: the contact position where the waste liquid tray 81 contacts the cover 72 (refer to Figure 7B ), the waste liquid tray 81 is separated from the cover 72 by a predetermined distance (refer to Fig. 7E ).

[0071] Next, the structure of the cover unit 31 will be described in detail. Figure 8 It is a perspective view showing the cover unit 31 . Fig. 9 It is a plan view showing the cover unit 31 . Fig.10 Yes means Fig. 9 Cross-sectional view of section X-X. Fig.11 It is an exploded view showing the cover unit 31 . Fig.12 1 and 2 are diagrams showing the flows of the air A and the humidified air WA in the cover unit 31 . Fig.13 It is a plan view showing the positions of the humidification tank 92 and the recovery tank 94 . Fig.14 It is a cross-sectional view showing the flow of the humidified air WA in the cap 72 .

[0072] [build]

[0073] Cover 72 (refer to Figures 8 to 10 ) is formed into a box shape that opens upward. The cover 72 includes: a bottom 72B that is roughly rectangular with the front-to-back direction as the long side direction, and a side wall portion 72W that stands upright from the edge of the bottom 72B to the upper side. The side wall portion 72W is formed of a flexible material such as rubber. An air inlet 72NA and an exhaust port 72EA are provided on the bottom 72B. On the right rear side and the left side of the cover 72, an air inlet 72NA is provided on the rear side, and an exhaust port 72EA is provided on the front side. On the right front side of the cover 72, an air inlet 72NA is provided on the front side, and an exhaust port 72EA is provided on the rear side.

[0074] [Humidification tank, recovery tank]

[0075] Below the frame 71 (see Figure 8 , 11 13) The same number of humidifying tanks 92 as the number of covers 72 (three in this embodiment) and one recovery tank 94 are provided. The humidifying tanks 92 and the recovery tanks 94 are supported by the frame 91. Each humidifying tank 92 is respectively arranged below the air inlet 72NA of each cover 72. In a top view, the recovery tank 94 has a shape including all the exhaust ports 72EA and is arranged below all the exhaust ports 72EA.

[0076] An air intake pipe 72N is connected to the air intake port 72NA of each cover 72, and the air intake pipe 72N connects the cover 72 with the humidification tank 92 below it (see Fig.10 ). An exhaust pipe 72E is connected to the exhaust port 72EA of each cover 72, and the exhaust pipe 72E connects the cover 72 and the recovery tank 94. That is, the three exhaust pipes 72E are connected to the recovery tank 94.

[0077] The air pump 95 passes through the recovery flow path 95E (see Figure 8 , Fig. 9 , Fig.11 ) is connected to the recovery tank 94, and is connected to all the humidification tanks 92 through the supply flow path 95N. The air pump 95 recovers the air A from the recovery tank 94 through the recovery flow path 95E, and supplies the recovered air A to all the humidification tanks 92 through the supply flow path 95N (refer to Fig.12 ).

[0078] All humidification tanks 92 are connected via a connecting pipe 92C (see Fig.10 , Fig.11 , Fig.12) is connected to the humidification sub-tank 93. The humidification sub-tank 93 is connected to: a humidification medium tank 93T and a humidification medium pump 93P. The humidification medium tank 93T stores a humidification medium WM (refer to Fig.14 The humidifying medium WM is, for example, water. The humidifying medium pump 93P supplies the humidifying medium WM from the humidifying medium tank 93T to the humidifying sub-tank 93. The humidifying sub-tank 93 is provided with a liquid level sensor 93S, which detects the liquid level in the humidifying sub-tank 93 (refer to Figure 8 , Fig. 9 , Fig.11 The humidifying tank 92 is provided with a heater 92H, and the heater 92H heats the humidifying medium WM (refer to Fig.10 ).

[0079] Next, the basic operation of the maintenance device 30 will be described. Fig. 7A ), the head unit 11 is located at the image forming position, and the cover unit 31 is located at the home position. The wiping unit 32 is placed on the cover unit 31. That is, the waste liquid tray 81 is in contact with the cover 72. The control unit 2 executes the following processing at a predetermined time. The predetermined time is, for example, the time when the viscosity of the ink in the nozzle 14N is estimated to increase, specifically, when the period when the image forming task is not performed continues for a predetermined period.

[0080] First, the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see Figure 7B Next, the control unit 2 activates the cover sliding device 34 to slide the cover unit 31 toward the maintenance position (see Figure 7C ). At this time, since the wiper unit 32 is placed on the cover unit 31, the wiper unit 32 also slides toward the maintenance position together with the cover unit 31. Next, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to a height at which the nozzle surface 14F contacts the cleaning member 82 (see Fig.7D ).

[0081] Next, after forcibly discharging a predetermined amount of ink from the inkjet head 12, the control unit 2 supplies cleaning liquid to the nozzle surface 14F and slides the cleaning member 82 along the nozzle surface 14F. In this way, the ink remaining on the nozzle surface 14F is diluted with the cleaning liquid, and the waste liquid containing the ink and the cleaning liquid is scraped by the cleaning member 82 and dropped into the waste liquid tray 81.

[0082] Next, the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see Figure 7C ). Next, the control unit 2 activates the cover sliding device 34 to slide the cover unit 31 and the wiping unit 32 to the original position (refer to Figure 7B ).

[0083] Next, the control unit 2 activates the wiping lifting device 35 to raise the wiping unit 32 to the separation position (see Fig. 7E Next, the control unit 2 activates the cover sliding device 34 to slide the cover unit 31 toward the maintenance position (see Figure 7F ). At this time, since the wiping unit 32 is separated from the cover unit 31, the wiping unit 32 remains at the original position, and only the cover unit 31 slides toward the maintenance position.

[0084] Next, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to a height where the nozzle surface 14F contacts the cap 72 (see Figure 7G ). In this way, the cap 72 is mounted on the nozzle surface 14F.

[0085] Next, the control unit 2 humidifies the inside of the cover 72. The control unit 2 monitors the measured value of the liquid level sensor 93S and keeps the liquid level in the humidification sub-tank 93 within a predetermined range. Specifically, when the measured value of the liquid level is lower than the predetermined range, the humidification medium pump 93P is used to replenish a predetermined amount of humidification medium WM from the humidification medium tank 93T to the humidification sub-tank 93. Since the humidification sub-tank 93 is connected to the humidification tank 92 through the connecting pipe 92C, the liquid level of the humidification medium WM in the humidification sub-tank 93 and all the humidification tanks 92 is uniform.

[0086] Air pump 95 (refer to Fig.12 ) The air A is recovered from the recovery tank 94 via the recovery flow path 95E, and the recovered air A is supplied to all the humidification tanks 92 via the supply flow path 95N. The end of the supply flow path 95N on the humidification tank 92 side is arranged at a position lower than the liquid level of the humidification medium WM (refer to Fig.14 ). Therefore, in the humidifying tank 92, air A is blown into the humidifying medium WM to generate bubbles B. While the bubbles B float to the liquid surface, the water vapor pressure of the bubbles B increases. In addition, the humidifying medium WM in the humidifying tank 92 is heated by the heater 92H, so it is easy to generate water vapor. Therefore, the space above the liquid surface in the humidifying tank 92 is filled with humidified air WA with increased water vapor pressure, and the humidified air WA flows into the cover 72 through the air inlet pipe 72N.

[0087] On the other hand, in the recovery tank 94, since the air A is sucked by the air pump 95, a negative pressure is generated. Therefore, an airflow of the humidified air WA from the air inlet 72NA toward the exhaust port 72EA is generated in the cover 72. In addition, since the humidified air WA heated by the heater 92H is supplied to the cover 72, convection is generated in the cover 72, and the high-temperature humidified air WA is supplied to the nozzle surface 14F. In this way, the humidified air WA contacts the ink in the nozzle 14N, and the viscosity of the ink is suppressed from increasing.

[0088] When an image forming task is executed, the control unit 2 activates the head lifting device 11L to raise the head unit 11 to the retracted position (see Figure 7F ), the cover sliding device 34 is activated to slide the cover unit 31 to the original position (refer to Fig. 7E ), the wiping lifting device 35 is activated, and the wiping unit 32 is lowered to the contact position (refer to Figure 7B ). Then, the control unit 2 activates the head lifting device 11L to lower the head unit 11 to the image forming position to perform the image forming task.

[0089] In addition, the humidified air WA flowing into the cap 72 through the air inlet pipe 72N rises toward the nozzle surface 14F, so the humidified air WA directly contacts the nozzle surface 14F. In this case, condensation occurs on the nozzle surface 14F, and the ink may be pulled by the condensation and leak out of the nozzle 14N. The fallen ink may accumulate in the cap 72, hindering the flow of the humidified air WA and clogging the air inlet pipe 72N.

[0090] Therefore, the maintenance device 30 of the present embodiment includes the suppression member 73 . Fig.15 It is a cross-sectional view showing the cover unit 31 including the suppression member 73 . Fig.16 7 is a top view showing a cover 72 having a suppressing member 73. Fig.15 Yes means Fig.16 Cross-sectional view of section XV-XV.

[0091] The maintenance device 30 of this embodiment includes: a cap 72 mounted on the nozzle surface 14F of the inkjet head 12, an air inlet 72NA provided in the cap 72, and a suppressing member 73 provided at least between the air inlet 72NA and the nozzle surface 14F. The suppressing member 73 is separated from the air inlet 72NA and the nozzle surface 14F. The first gap G1 is between the suppressing member 73 and the air inlet 72NA, and the second gap G2 is between the suppressing member 73 and the nozzle surface 14F. Specifically, it is described as follows.

[0092] The suppression member 73 is disposed above the air inlet 72NA. The suppression member 73 is separated from the air inlet 72NA and from the nozzle surface 14F. The suppression member 73 is a plate-shaped member whose thickness direction is the up-down direction and is formed of resin. The suppression member 73 is supported by a support 73P, and the support 73P is disposed at the bottom 72B of the cover 72. The suppression member 73 is opposite to the air inlet 72NA. The dimensions of the suppression member 73 in the front-to-back direction and the left-to-right direction are larger than those of the air inlet 72NA. The suppression member 73 is disposed so as to cover at least the entire air inlet 72NA when viewed from above. A first gap G1 is provided between the air inlet 72NA and the lower surface of the suppression member 73. A second gap G2 is provided between the nozzle surface 14F and the upper surface of the suppression member 73.

[0093] A portion WA1 (see FIG. 1 ) of the humidified air that flows into the cover 72 from the air inlet 72NA Fig.15 ) flows forward from the first gap G1 and is sucked into the exhaust port 72EA. Another portion WA2 of the humidified air flows from the first gap G1 to the rear of the suppression member 73 and enters the second gap G2, flows forward from the second gap G2 and is sucked into the exhaust port 72EA. Another portion WA3 of the humidified air (see Fig.16 ) flows forward from the space on the left and right of the suppression member 73 and is sucked into the exhaust port 72EA. That is, above the air inlet 72NA, the humidified air WA flows along the lower surface and the upper surface of the suppression member 73, so the humidified air WA does not directly contact the nozzle 14 surface F above the air inlet 72NA. As a result, it is possible to suppress the generation of condensation on the nozzle surface 14F, and prevent the ink from being pulled by the condensation and leaking from the nozzle 14N.

[0094] The reason why the suppression member 73 is formed of resin is as follows. The suppression member 73 absorbs heat from the humidified air WA, so condensation may occur on the suppression member 73. In particular, in the present embodiment, the humidifying tank 92 is provided with a heater 92H in order to increase the amount of water vapor in the humidified air WA, so condensation is easily generated. When condensation occurs, the water vapor pressure of the humidified air WA decreases, thereby causing the humidification effect on the ink in the nozzle 14N to decrease. In order to suppress condensation, it is desirable to form the suppression member 73 with a raw material having a lower thermal conductivity. Generally, the thermal conductivity of resin is lower than that of metal, so it is preferably the raw material of the suppression member 73.

[0095] According to the maintenance device 30 of the present embodiment described above, the cover 72 mounted on the nozzle surface 14F of the inkjet head 12, the air inlet 72NA provided in the cover 72, and the suppression member 73 provided at least between the air inlet 72NA and the nozzle surface 14F. The suppression member 73 is separated from the air inlet 72NA and the nozzle surface 14F. The first gap G1 is provided between the suppression member 73 and the air inlet 72NA, and the second gap G2 is provided between the suppression member 73 and the nozzle surface 14F. According to the present embodiment, it is possible to prevent the humidified air WA from directly contacting the nozzle surface 14F.

[0096] Moreover, according to the maintenance device 30 of this embodiment, the suppression member 73 is formed of resin. According to this embodiment, condensation of the humidified air WA can be suppressed.

[0097] Furthermore, the inkjet recording apparatus according to the present embodiment includes the inkjet head 12 and the maintenance device 30. According to the present embodiment, it is possible to suppress an increase in the viscosity of the ink in the nozzles 14N of the inkjet head 12.

[0098] [Second embodiment]

[0099] Fig.17It is a cross-sectional view showing a cover unit 31 including a suppression member 74 according to the second embodiment. Fig.18 2 is a top view showing a cover 72 including a suppressing member 74 according to the second embodiment. Fig.17 Yes means Fig.18 Cross-sectional view of section XVII-XVII.

[0100] The suppression component 74 is arranged along the direction from the air inlet 72NA side toward the exhaust port 72EA side. Specifically, the suppression component 74 is a rectangular plate-shaped component with the direction from the air inlet 72NA side toward the exhaust port 72EA side as the long side direction. The suppression component 74 is supported by a support 74P, and the support 74P is provided at the bottom 72B of the cover 72. The rear end portion of the suppression component 74 is arranged above the air inlet 72NA. The front end portion of the suppression component 74 is located at a position farther back than the exhaust port 72EA. The suppression component 74 is separated from the air inlet 72NA and is separated from the nozzle surface 14F. A first gap G1 is provided between the air inlet 72NA and the lower surface of the suppression component 74. A second gap G2 is provided between the nozzle surface 14F and the upper surface of the suppression component 74.

[0101] The suppression member 74 includes a through hole 74H extending from the air inlet 72NA side to the nozzle surface 14F side at a position not facing the air inlet 72NA. The through holes 74H are provided at a plurality of locations (three locations in this embodiment) in the direction from the air inlet 72NA side to the exhaust port 72EA side.

[0102] A portion WA1 (see FIG. 1 ) of the humidified air that flows into the cover 72 from the air inlet 72NA Fig.17 ) flows forward along the first gap G1 and is sucked into the exhaust port 72EA. Another portion WA2 of the humidified air flows from the first gap G1 to the rear of the suppression member 74 and enters the second gap G2, flows forward along the second gap G2 and is sucked into the exhaust port 72EA. Another portion WA3 of the humidified air (see Fig.18 ) flows forward along the space on the left and right of the suppression member 74 and is sucked into the exhaust port 72EA. That is, the humidified air WA flows along the lower surface and the upper surface of the suppression member 74 in a wider range than that in the first embodiment, so that the humidified air WA can be prevented from directly contacting the nozzle surface 14F in a wider range than that in the first embodiment.

[0103] In addition, a portion WA4 of the humidified air flowing toward the exhaust port 72EA along the first gap G1 flows from the first gap G1 to the second gap G2 through the through hole 74H, thereby compensating for the insufficient supply of the humidified air WA caused by the suppression member 74. In addition, the humidified air WA is also supplied to the nozzle surface 14F separated from the air inlet 72NA through the through hole 74H, thereby improving the uniformity of humidification of the nozzle surface 14F.

[0104] According to the maintenance device 30 of the present embodiment described above, the cover 72 has the exhaust port 72EA, and the suppression member 74 is provided in the direction from the air inlet 72NA side toward the exhaust port 72EA side. According to the present embodiment, it is possible to prevent the humidified air WA from directly contacting the nozzle surface 14F in a wide range in the direction from the air inlet 72NA side toward the exhaust port 72EA side.

[0105] According to the maintenance device 30 of this embodiment, the suppressing member 74 includes the through hole 74H extending from the air inlet 72NA side to the nozzle surface 14F side at a position not facing the air inlet 72NA. According to this embodiment, the insufficient supply of the humidified air WA caused by the suppressing member 74 can be compensated.

[0106] According to the maintenance device 30 of the present embodiment, the cap 72 includes the exhaust port 72EA, and the through holes 74H are provided at a plurality of locations in the direction from the air inlet 72NA side toward the exhaust port 72EA side. According to the present embodiment, the uniformity of humidification of the nozzle surface 14F can be improved.

[0107] [Third embodiment]

[0108] Fig.19 1 is a top view of a cover 72 having a suppressing member 75 according to a third embodiment. The maintenance device 30 of this embodiment comprises: a cover 72 mounted on the nozzle surface 14F of the inkjet head 12, an air inlet 72NA and an exhaust port 72EA provided on the cover 72, and a suppressing member 75 provided at least between the air inlet 72NA and the nozzle surface 14F. The suppressing member 75 is separated from the air inlet 72NA and the nozzle surface 14F. A first gap G1 is provided between the suppressing member 75 and the air inlet 72NA. A second gap G2 is provided between the suppressing member 75 and the nozzle surface 14F. The suppressing member 75 comprises, at a position not opposite to the air inlet 72NA, a plurality of through holes 75H penetrating from the air inlet 72NA side to the nozzle surface 14F side. The diameters of the plurality of through holes 75H are equal. The closer to the exhaust port 72EA, the greater the number of through holes 75H per unit area.

[0109] Specifically, the through hole groups 75Hs including the plurality of through holes 75H are provided at a plurality of locations along the direction from the air inlet 72NA side toward the exhaust port 72EA side, and the distance between adjacent through hole groups 75Hs is shortened as it is closer to the exhaust port 72EA. Fig.19 In the embodiment, the number of through holes 75H included in the through hole group 75Hs is five, but the number of through holes 75H included in the through hole group 75Hs may be any number.

[0110] According to the present embodiment, the uniformity of humidification of the nozzle surface 14F can be improved compared to the case where the number of through holes 75H per unit area is the same. In addition, according to the present embodiment, the uniformity of humidification of the nozzle surface 14F can be improved compared to the case where the plurality of through hole groups 75Hs are arranged at equal intervals in the direction from the air inlet 72NA side toward the exhaust port 72EA side.

[0111] [Fourth embodiment]

[0112] Fig. 20 1 is a top view showing a cover 72 having a suppressing member 76 according to a fourth embodiment. In the maintenance device 30 of the present embodiment, through hole groups 76Hs1, 76Hs2, 76Hs3, and 76Hs4 including a plurality of through holes 76H are provided at a plurality of locations along a direction from the air inlet 72NA side toward the exhaust port 72EA side, and the number of through holes 76H in each of the through hole groups 76Hs1, 76Hs2, 76Hs3, and 76Hs4 increases as the distance from the exhaust port 72EA increases.

[0113] exist Fig. 20 In the example, through hole group 76Hs1 includes 5 through holes 76H. Through hole group 76Hs2 includes 9 through holes 76H. Through hole group 76Hs3 includes 14 through holes 76H. Through hole group 76Hs4 includes 18 through holes 76H. In this example, when the number of through holes 76H contained in each of through hole groups 76Hs1, 76Hs2, 76Hs3, and 76Hs4 exceeds 5, through holes 76H are arranged in a staggered manner, but in through hole groups 76Hs1, 76Hs2, 76Hs3, and 76Hs4, multiple through holes 76H can be arranged arbitrarily. In addition, in Fig. 20 In the embodiment, the closer to the exhaust port 72EA, the shorter the distance between the adjacent through hole groups 76Hs1, 76Hs2, 76Hs3 and 76Hs4, but the distance between the adjacent through hole groups 76Hs1, 76Hs2, 76Hs3 and 76Hs4 may be constant. According to the present embodiment, the uniformity of humidification of the nozzle surface 14F can be improved compared to the case where the number of through holes 76H included in each of the through hole groups 76Hs1, 76Hs2, 76Hs3 and 76Hs4 is the same.

[0114] [Fifth Embodiment]

[0115] Fig.217 is a top view of a cover 72 having a suppressing member 77 according to a fifth embodiment. The arrangement of the through holes 77H is different from that of the third and fourth embodiments. In this embodiment, the diameters of the plurality of through holes 77H are equal, and the number of through holes 77H per unit area increases as the number of through holes 77H per unit area increases as the number of through holes 77H per unit area increases. According to this embodiment, the uniformity of humidification of the nozzle surface 14F can be improved compared to a case where the number of through holes 77H per unit area is the same.

[0116] [Sixth embodiment]

[0117] Fig. 22 1 is a top view of a cover 72 having a suppressing member 78 according to a sixth embodiment. The maintenance device 30 of this embodiment includes: a cover 72 mounted on the nozzle surface 14F of the inkjet head 12, an air inlet 72NA and an exhaust port 72EA provided on the cover 72, and a suppressing member 78 provided at least between the air inlet 72NA and the nozzle surface 14F. The suppressing member 78 is separated from the air inlet 72NA and the nozzle surface 14F. A first gap G1 is provided between the suppressing member 78 and the air inlet 72NA. A second gap G2 is provided between the suppressing member 78 and the nozzle surface 14F. The suppressing member 78 includes, at a position not facing the air inlet 72NA, a plurality of through holes 78H1, 78H2, and 78H3 extending from the air inlet 72NA side to the nozzle surface 14F side, and the diameters of the through holes 78H1, 78H2, and 78H3 are larger as they are closer to the exhaust port 72EA.

[0118] Specifically, the through hole group 78H1s includes a plurality of through holes 78H1, the through hole group 78H2s includes a plurality of through holes 78H2, and the through hole group 78H3s includes a plurality of through holes 78H3. The through hole groups 78H1s, 78H2s, and 78H3s are provided at a plurality of locations along the direction from the air inlet 72NA side toward the exhaust port 72EA side. The closer to the exhaust port 72EA, the larger the diameter of the through holes 78H1, 78H2, and 78H3 of each through hole group 78H1s, 78H2s, and 78H3s. According to the present embodiment, compared with the case where the diameters of the through holes 78H1, 78H2, and 78H3 of each through hole group 78H1s, 78H2s, and 78H3s are equal, the uniformity of humidification of the nozzle surface 14F can be improved.

[0119] Fig.24 Yes means Fig. 22The suppression member 78 is provided along the direction from the air inlet 72NA side toward the exhaust port 72EA side, and a plurality of through holes 78H1, 78H2, 78H3 are provided at both end sides of the suppression member 78 in the width direction (left-right direction) intersecting the direction from the air inlet 72NA side toward the exhaust port 72EA side. The plurality of through holes 78H1, 78H2, 78H3 penetrate from the bottom surface of the suppression member 78 to the upper surface. According to the present embodiment, compared with the case where the through holes 78H1, 78H2, 78H3 are provided in the center of the width direction (left-right direction), the uniformity of humidification in the width direction (left-right direction) of the nozzle surface 14F can be improved.

[0120] Fig.25 2 is a cross-sectional view showing a first modification of the sixth embodiment. A plurality of through holes 78H1, 78H2, and 78H3 penetrate from the bottom surface to the side surface of the suppression member 78. According to this embodiment, the uniformity of humidification in the width direction of the nozzle surface 14F can also be improved.

[0121] Fig.26 2 is a cross-sectional view showing a second modification of the sixth embodiment. A plurality of through holes 78H1, 78H2, 78H3 penetrate from the bottom surface to the ridgeline intersecting the upper surface and the side surface of the suppression member 78. According to this embodiment, the uniformity of humidification in the width direction of the nozzle surface 14F can also be improved.

[0122] [Seventh embodiment]

[0123] Fig.23 7 is a plan view of a cover 72 having a suppressing member 79 according to the seventh embodiment. In the present embodiment, the diameters of the through holes 79H1, 79H2, ..., 79H9 gradually increase as they approach the exhaust port 72EA. According to the present embodiment, the uniformity of humidification of the nozzle surface 14F can also be improved.

[0124] [Eighth Embodiment]

[0125] Fig. 27 It is a cross-sectional view showing a cover unit 31 including a suppression member 74 according to the eighth embodiment. Fig.28 74 is a top view showing a cover 72 having a suppressing member 74 according to an eighth embodiment. Fig.17 ), since the end of the exhaust port 72EA side of the suppression component 74 is located rearward of the exhaust port 72EA, there is a problem that it is difficult to supply humidified air WA to the area R on the nozzle surface 14F that is closer to the front than the end of the exhaust port 72EA side of the suppression component 74.

[0126] Therefore, in the present embodiment, the suppression member 74 is opposed to the exhaust port 72EA. Specifically, the end of the suppression member 74 on the exhaust port 72EA side (i.e., a portion of the suppression member 74) is opposed to the exhaust port 72EA. Therefore, the suppression member 74 is provided in a manner covering the exhaust port 72EA. The suppression member 74 is separated from the exhaust port 72EA. According to the present embodiment, since the humidified air WA flowing forward along the second gap G2 goes around the first gap G1 from the front of the suppression member 74 and is sucked into the exhaust port 72EA, the humidified air WA can also be supplied to the nozzle surface 14F on the exhaust port 72EA side. Therefore, according to the present embodiment, the uniformity of humidification of the nozzle surface 14F can be improved.

Claims

1. A maintenance device comprising: a cap including an air inlet and an air outlet and mounted on the nozzle face of the inkjet head; and The suppression member is opposed to the air inlet and is provided between the air inlet and the nozzle surface, and is separated from the air inlet and the nozzle surface.

2. The maintenance device according to claim 1, characterized in that: The suppressing member includes a plurality of through holes penetrating from the air inlet side to the nozzle surface side at a position not facing the air inlet.

3. The maintenance device according to claim 2, characterized in that: The closer to the exhaust port, the larger the diameter of the through hole.

4. The maintenance device according to claim 2, characterized in that: A through hole group including a plurality of the through holes is provided at a plurality of locations along a direction from the air inlet side toward the air outlet side, The closer to the exhaust port, the larger the diameter of the through holes in each of the through hole groups.

5. The maintenance device according to claim 2, characterized in that: The closer to the exhaust port, the greater the number of the through holes per unit area.

6. The maintenance device according to claim 2, characterized in that: The suppression member is provided in a direction from the air inlet side toward the air outlet side, The plurality of through holes are provided on both end sides of the suppression member in a width direction intersecting a direction from the air inlet side toward the air outlet side.

7. The maintenance device according to claim 6, characterized in that: The plurality of through holes penetrate the suppression member from the bottom surface to the upper surface, the side surface, or a ridge line where the upper surface and the side surface intersect.

8. The maintenance device according to claim 1, characterized in that: The suppressing member is formed of resin.

9. The maintenance device according to claim 1, characterized in that: Humidified air flows into the cover from the air inlet.

10. An inkjet recording device comprising: An inkjet head, and the maintenance device according to any one of claims 1 to 9.

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