Inkjet recording device

Abstract

To provide an inkjet recording device capable of efficiently cleaning an ink dropped into an ink recovery tray with a cleaning fluid.SOLUTION: An inkjet recording device includes: an ink recovery tray; and a cleaning fluid supply mechanism. The ink recovery tray is disposed facing a recording head when recovery operation of a recording head is performed to recovery an ink pushed out to an ink discharge surface of the recording head. The cleaning fluid supply mechanism supplies a cleaning fluid onto the ink recovery tray. The ink recovery tray has a cleaning fluid receiving part, a cleaning fluid diffusion part, a waste ink receiving part, and a waste ink discharge part and forms a descending slope from the cleaning fluid receiving part to the waste ink discharge part. The waste ink receiving part is provided with a plurality of groove parts extending along the descending slope and respectively having V-shaped cross sections. The cleaning fluid diffusion part is provided with a pair of ribs which extends in a taper shape from the cleaning fluid receiving part side toward the waste ink receiving part side.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to an inkjet recording apparatus that performs recording by discharging ink onto a recording medium, and more particularly to an inkjet recording apparatus provided with an ink recovery tray for receiving ink extruded from an ink ejection surface of a recording head.

Background Art

[0002] As a recording apparatus such as a facsimile machine, a copying machine, or a printer, an inkjet recording apparatus that discharges ink onto a recording medium such as paper or an OHP sheet to form an image is widely used because it can form a high-definition image.

[0003] In such an inkjet recording apparatus, generally, in order to prevent drying of the ink in the ink ejection nozzles provided with openings on the ink ejection surface of the recording head and clogging of the nozzles, the ink is forcibly extruded (purged) from the nozzles. By this extrusion of the ink, thickened ink, air bubbles, impurities, etc. in the nozzles can be discharged. Further, the extruded ink redissolves the mist (ink residue) adhering to the ink ejection surface. Then, after the ink is extruded, the ink adhering to the ink ejection surface (nozzle surface) is wiped off with a blade-shaped wiper to perform a recovery process of the recording head.

[0004] The ink wiped off by the wiper falls onto an ink recovery tray for receiving the ink, is recovered, and is discharged from the ink recovery tray as waste liquid. However, the ink that has fallen onto the ink recovery tray dries and its fluidity decreases. The ink with decreased fluidity accumulates on the ink recovery tray and contaminates the recording medium by adhering to the conveyance belt. In addition, the solidified ink clogs the ink discharge flow path, causing contamination and failure inside the apparatus.

[0005] As a method for suppressing clogging of the ink discharge passage, for example, Patent Document 1 discloses a waste ink tray having an ink inflow portion including a first inlet through which ink flows in and a second inlet disposed at a position higher than the first inlet, and an ink detection unit that detects the presence or absence of ink flowing into the second inlet. When the ink detection unit detects the inflow of ink into the second inlet, an inkjet recording apparatus that detects the blockage of the first inlet is disclosed.

[0006] Patent Document 2 discloses a maintenance unit including a wiper that wipes ink from a recording head and a wiper carriage that moves while holding the wiper. A communication portion that communicates in the vertical direction is formed in a portion facing the ink discharge surface of the holding sheet metal that holds the wiper, and an ink guide member having an upper opening and a lower opening is provided in the communication portion.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] Among the maintenance units as described above, there is one that supplies a cleaning liquid to an ink recovery tray by a liquid supply mechanism. In this configuration, the cleaning liquid contacts the ink fixed on the ink recovery tray before flowing into the ink discharge passage and is washed away while dissolving. Therefore, it is necessary to efficiently circulate the cleaning liquid over the entire area of the ink recovery tray.

[0009] However, when the liquid supply mechanism and the ink recovery tray are constituted by separate members, an error may occur in the dropping position of the cleaning liquid, and the cleaning liquid may not pass through the target flow path. As a result, the cleaning liquid cannot be circulated over the entire area of the ink recovery tray, which may lead to a decrease in cleaning efficiency.

[0010] In view of the above problems, an object of the present invention is to provide an inkjet recording apparatus capable of efficiently cleaning ink dropped on an ink recovery tray using a cleaning liquid.

Means for Solving the Problems

[0011] To achieve the above object, a first configuration of the present invention is an inkjet recording apparatus including an ink recovery tray and a cleaning liquid supply mechanism. The ink recovery tray is disposed opposite to the recording head when the recovery operation of the recording head that discharges ink onto the recording medium is executed, and recovers the ink extruded onto the ink discharge surface of the recording head. The cleaning liquid supply mechanism supplies a cleaning liquid for cleaning the ink onto the ink recovery tray. The ink recovery tray includes a cleaning liquid receiving portion that receives the cleaning liquid dropped from the cleaning liquid supply mechanism, a waste ink receiving portion that faces the ink discharge surface, a cleaning liquid diffusion portion disposed between the cleaning liquid receiving portion and the waste ink receiving portion, and a waste ink discharge portion disposed adjacent to the opposite side of the waste ink receiving portion from the cleaning liquid diffusion portion, and has a downward gradient from the cleaning liquid receiving portion toward the waste ink discharge portion. A plurality of V-shaped groove portions in cross-sectional view extending along the downward gradient are formed in the waste ink receiving portion. A pair of ribs that taper and spread from the cleaning liquid receiving portion side toward the waste ink receiving portion side are formed in the cleaning liquid diffusion portion.

Effects of the Invention

[0012] According to the first configuration of the present invention, by providing a plurality of groove portions having a V-shaped cross-section in the waste ink receiving portion, the cleaning liquid flowing into the waste ink receiving portion reaches the waste ink discharging portion along the groove portions. Therefore, for example, the cleaning liquid is more likely to flow through the entire area of the waste ink receiving portion compared to the case where the waste ink receiving portion has a single V-shape. Further, by providing a cleaning liquid diffusing portion in which a pair of ribs that taper and spread from the cleaning liquid receiving portion side toward the waste ink receiving portion side are formed, the cleaning liquid dropped into the cleaning liquid receiving portion can be reliably spread to the outside in the tray width direction and then flowed into the waste ink receiving portion.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0014] [1. Configuration of Inkjet Recording Apparatus] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side cross-sectional view showing a schematic configuration of a printer 100 as an inkjet recording apparatus according to an embodiment of the present invention. The printer 100 includes a paper feed cassette 2 which is a paper storage section. The paper feed cassette 2 is disposed below the inside of the printer main body 1. Inside the paper feed cassette 2, a paper P which is an example of a recording medium is stored.

[0015] A paper feed device 3 is disposed on the downstream side in the paper feed direction of the paper feed cassette 2, that is, above the right side of the paper feed cassette 2 in FIG. 1. By this paper feed device 3, the paper P is sent out one by one in a separated manner toward the upper right of the paper feed cassette 2 in FIG. 1.

[0016] The printer 100 includes a first paper conveyance path 4a inside thereof. The first paper conveyance path 4a is located in the upper right in the paper feed direction with respect to the paper feed cassette 2. The paper P sent out from the paper feed cassette 2 is conveyed vertically upward along the side surface of the printer main body 1 by the first paper conveyance path 4a.

[0017] At the downstream end of the first paper conveyance path 4a in the paper conveyance direction, a registration roller pair 13 is provided. Further, a first conveyance unit 5 and a recording section 9 are disposed in the immediate vicinity on the downstream side in the paper conveyance direction of the registration roller pair 13. The paper P sent out from the paper feed cassette 2 reaches the registration roller pair 13 through the first paper conveyance path 4a. The registration roller pair 13 corrects the skew feed of the paper P, measures the timing with the ink ejection operation performed by the recording section 9, and sends out the paper P toward the first conveyance unit 5 (particularly the first conveyance belt 8 described later).

[0018] The paper P sent out to the first transport unit 5 by the resist roller pair 13 is transported by the first transport belt 8 to a position facing the recording unit 9 (particularly the recording heads 17a to 17c described later). By discharging ink from the recording unit 9 onto the paper P, an image is recorded on the paper P. At this time, the discharge of ink in the recording unit 9 is controlled by the control device 110 inside the printer 100.

[0019] In the paper transport direction, on the downstream side of the first transport unit 5 (the left side in FIG. 1), a second transport unit 12 is arranged. The paper P on which an image has been recorded by the recording unit 9 is sent to the second transport unit 12. The ink discharged onto the surface of the paper P is dried while passing through the second transport unit 12.

[0020] In the paper transport direction, on the downstream side of the second transport unit 12 and near the left side surface of the printer main body 1, a decurler unit 14 is provided. The paper P on which the ink has been dried by the second transport unit 12 is sent to the decurler unit 14, and the curl generated in the paper P is corrected.

[0021] In the paper transport direction, on the downstream side of the decurler unit 14 (above in FIG. 1), a second paper transport path 4b is provided. When double-sided recording is not performed, the paper P that has passed through the decurler unit 14 passes through the second paper transport path 4b and is discharged to a paper discharge tray 15a provided outside the left side surface of the printer 100. Below the paper discharge tray 15a, a sub-discharge tray 15b for discharging unnecessary paper P (waste paper) on which printing defects or the like have occurred is provided.

[0022] Above the upper part of the printer main body 1 and above the recording unit 9 and the second transport unit 12, a reverse transport path 16 for performing double-sided recording is provided. When performing double-sided recording, after the recording on one side (the first side) of the paper P is completed and the paper P that has passed through the second transport unit 12 and the decurler unit 14, it passes through the second paper transport path 4b and is sent to the reverse transport path 16.

[0023] The sheet P sent to the reverse conveyance path 16 has its conveyance direction switched subsequently for recording on the other side (second side) of the sheet P. Then, the sheet P passes through the upper part of the printer main body 1 and is sent rightward, and after passing through the registration roller pair 13 with the second side facing upward, it is sent again to the first conveyance unit 5. In the first conveyance unit 5, the sheet P is conveyed to a position facing the recording unit 9, and an image is recorded on the second side by ink ejection from the recording unit 9. The sheet P after double-sided recording passes through the second conveyance unit 12, the decurler unit 14, and the second sheet conveyance path 4b in sequence and is discharged to the sheet discharge tray 15a.

[0024] Also, below the second conveyance unit 12, a maintenance unit 19 and a cap unit 20 are arranged. When performing a purge, the maintenance unit 19 horizontally moves below the recording unit 9, wipes off the ink extruded from the ink ejection ports 18 (all refer to FIG. 2) of the recording heads 17a to 17c, and collects the wiped-off ink. Note that a purge refers to an operation of forcibly extruding ink from the ink ejection ports 18 of the recording heads 17a to 17c in order to discharge the thickened ink, foreign substances, and air bubbles in the ink ejection ports 18. The cap unit 20 horizontally moves below the recording unit 9 when capping the ink ejection surfaces of the recording heads 17a to 17c, and further moves upward to be mounted on the lower surfaces of the recording heads 17a to 17c.

[0025] FIG. 2 is a plan view of the recording unit 9. FIG. 3 is a perspective view of the recording unit 9 as viewed from above. As shown in FIGS. 2 and 3, the recording unit 9 includes a head housing 10 and line heads 11Y, 11M, 11C, 11K. The line heads 11Y to 11K are held by the head housing 10 at a height at which a predetermined interval (for example, 1 mm) is formed with respect to the conveyance surface of the endless first conveyance belt 8 stretched over a plurality of rollers including the drive roller 6a and the driven roller 6b. The drive roller 6a runs the first conveyance belt 8 in the conveyance direction of the sheet P (arrow X direction).

[0026] Line heads 11Y to 11K each have a plurality (here, three) of recording heads 17a to 17c. The recording heads 17a to 17c are arranged in a staggered pattern along the intersecting direction, which is a direction intersecting the paper conveyance direction (arrow X direction). In the present embodiment, the intersecting direction is the same as the paper width direction (arrow YY' direction) orthogonal to the paper conveyance direction (arrow X direction). The recording heads 17a to 17c have a plurality of ink ejection ports 18 (nozzles). Each ink ejection port 18 is arranged at equal intervals in the intersecting direction (arrow YY' direction). From the line heads 11Y to 11K, inks of each color of yellow (Y), magenta (M), cyan (C), and black (K) (aqueous ink in the present embodiment) are respectively ejected toward the paper P conveyed by the first conveyance belt 8 through the ink ejection ports 18 of the recording heads 17a to 17c.

[0027] FIG. 4 is a side view of the recording heads 17a to 17c that constitute the line heads 11C to 11K of the recording unit 9, and FIG. 5 is a plan view of the recording heads 17a to 17c as viewed from the ink ejection surface F1 side. Since the recording heads 17a to 17c have the same shape and configuration, in FIGS. 4 and 5, the recording heads 17a to 17c are shown in a common drawing.

[0028] As shown in FIG. 5, on the ink ejection surface (nozzle surface) F1 of the recording heads 17a to 17c, a plurality (here, four blocks) of nozzle regions Ra to Rd in which a large number of ink ejection ports 18 (see FIG. 2) are arranged are provided. The ink ejection surface F1 is formed of, for example, SUS (stainless steel). Also, a water-repellent film (not shown) is formed on the ink ejection surface F1.

[0029] To the recording heads 17a to 17c that constitute each of the line heads 11Y to 11K, inks of four colors (yellow, magenta, cyan, and black) stored in ink tanks (not shown) are supplied for each color of the line heads 11Y to 11K.

[0030] Each of the recording heads 17a to 17c discharges ink from the ink discharge port 18 toward the sheet P that is adsorbed and held on the conveyance surface of the first conveyance belt 8 and conveyed in accordance with the control signal from the control unit (not shown) and the image data received from an external computer. As a result, a color image in which four colors of ink, yellow, magenta, cyan, and black, are superimposed is formed on the sheet P on the first conveyance belt 8. Further, a cleaning liquid supply unit 60 for supplying a cleaning liquid is provided at one end in the longitudinal direction (arrow YY' direction) of the recording heads 17a to 17c that is orthogonal to the sheet conveyance direction (arrow X direction). A large number of cleaning liquid supply ports 60a are formed in the cleaning liquid supply unit 60.

[0031] In the printer 100, in order to clean the ink discharge surface F1 of the recording heads 17a to 17c, at the start of printing after a long-term stop and during the printing operation, ink is extruded (purged) from the ink discharge ports 18 of all the recording heads 17a to 17c, and a cleaning liquid is supplied from the cleaning liquid supply port 60a to the cleaning liquid supply surface F2. The wiper 35 (see FIG. 8) executes a recovery operation of the recording heads 17a to 17c to wipe off the ink extruded onto the ink discharge surface F1 together with the cleaning liquid, in preparation for the next printing operation. The ink and the cleaning liquid wiped off from the ink discharge surface F1 are recovered by an ink recovery tray 50 (see FIG. 9) described later.

[0032] [2. Configuration of Maintenance Unit] FIG. 6 is a perspective view of the recording unit 9, the cap unit 30, and the maintenance unit 19 of the printer 100. As shown in FIG. 6, two guide rails 70a and 70b are fixed along both end portions parallel to the sheet conveyance direction (arrow X direction) below the recording unit 9. A pair of guide plates 71a and 71b are fixed to the guide rails 70a and 70b, and the side edge of the cap unit 30 is supported at the lower end portions of the guide plates 71a and 71b. Further, a carriage 72 is slidably supported on the guide rails 70a and 70b, and the maintenance unit 19 is placed on the carriage 72.

[0033] The cap unit 30 is capable of reciprocating between a first position directly below the recording unit 9 and a second position (the position in Fig. 6) retracted in the horizontal direction (the direction of arrow X) from the first position, and is configured to move upward (the direction of arrow Z) at the first position to cap the recording heads 17a to 17c.

[0034] The maintenance unit 19 is capable of reciprocating between a first position directly below the recording unit 9 and a second position (the position in Fig. 6) retracted in the horizontal direction (the direction of arrow X) from the first position, and is configured to move upward (the direction of arrow Z) at the first position to perform a wiping operation described later.

[0035] Specifically, outside the guide rail 70b, a drive motor 73 for moving the carriage 72 in the direction of arrow XX', a gear train (not shown) engaged with the rack teeth 72a of the drive motor 73 and the carriage 72, and a cover member 75 covering these are attached. When the drive motor 73 rotates forward, the gear train rotates, and the carriage 72 and the maintenance unit 19 move from the second position to the first position.

[0036] In addition, at the four corners of the carriage 72, support arms (not shown) that support the maintenance unit 19 from the lower surface side and are capable of swinging (standing up or lying down) are provided. Further, outside the carriage 71, a wipe lifting motor 76 for swinging the support arms and a gear train (not shown) engaged with the drive output gear of the wipe lifting motor 76 are attached.

[0037] When the wiper lifting motor 76 rotates forward, the gear train rotates, causing the support arm to swing (stand up). As a result, the maintenance unit 19 rises. Note that a unit lifting mechanism for moving the maintenance unit 19 in the vertical direction (arrow ZZ' direction) is constituted by the wiper lifting motor 76, the gear train, the support arm, etc. Further, a guide groove (not shown) extending in the vertical direction is formed on the inner surface of the carriage 71, and the maintenance unit 19 moves up and down along the guide groove.

[0038] FIG. 7 is a partially enlarged view of the maintenance unit 19 mounted on the printer 100 as viewed from above. The maintenance unit 19 includes a blade unit 31 to which a plurality of wipers 35 are fixed, a substantially rectangular wiper carriage 33 to which the blade unit 31 is attached, a support frame 40 that supports the wiper carriage 33, and an ink recovery tray 50 disposed on the upper surface of the support frame 40.

[0039] As shown in FIG. 7, rail grooves 41 are formed at opposite edges on the upper surface of the support frame 40, and the sliding pulleys 36 provided at four locations on the wiper carriage 33 abut against the rail grooves 41, so that the wiper carriage 33 is slidably supported with respect to the support frame 40 in the direction of arrow YY'.

[0040] A wiper drive motor for moving the wiper carriage 33 in the horizontal direction (arrow YY' direction) and a rack drive gear that engages with the rack of the wiper carriage 33 (both not shown) are attached to the support frame 40. When the wiper drive motor rotates forward and backward, the rack drive gear rotates forward and backward via the gear train, and the wiper carriage 33 reciprocates in the horizontal direction (arrow YY' direction).

[0041] The wiper 35 is a blade-shaped member made of rubber, for example, EPDM, for wiping the ink extruded from the ink ejection ports 18 of each of the recording heads 17a to 17c and the cleaning liquid supplied from the cleaning liquid supply unit 60. The wiper 35 is pressed against the wiping start position outside the nozzle regions Ra to Rd (see FIG. 5) where the ink ejection ports 18 are exposed from a substantially perpendicular direction, and wipes the ink ejection surface F1 including the nozzle regions Ra to Rd in a predetermined direction (arrow Y direction) by the movement of the wiper carriage 33.

[0042] Four wipers 35 are arranged at substantially equal intervals in the width direction (arrow XX' direction) of the blade unit 31, and a total of 12 wipers are arranged in three rows in the moving direction (arrow YY' direction) of the wiper carriage 33. Each wiper 35 is arranged at a position corresponding to the recording heads 17a to 17c (see FIG. 3) that constitute each of the line heads 11Y to 11K. The blade unit 31 is detachable from the wiper carriage 33, and is replaced when the wiper 35 is worn or damaged.

[0043] An ink recovery tray 50 for recovering the waste ink wiped from the ink ejection surface F1 by the wiper 35 is arranged on the upper surface of the support frame 40. The waste ink wiped from the ink ejection surface F1 by the wiper 35 and dropped into the ink recovery tray 50 passes through the ink recovery path and is recovered into a waste ink recovery tank (both not shown).

[0044] [3. Configuration of Ink Recovery Tray] FIG. 8 is a plan view of the ink recovery tray 50 mounted on the maintenance unit 19 of the present embodiment. FIG. 9 is a cross-sectional view taken along the longitudinal direction of the ink recovery tray 50 (cross-sectional view taken along the arrow AA in FIG. 8). The ink recovery tray 50 is formed with a cleaning liquid receiving portion 51, a cleaning liquid diffusion portion 52, a waste ink receiving portion 53, and a waste ink discharging portion 54 along the longitudinal direction (arrow DD' direction in FIG. 9).

[0045] As shown in FIG. 9, the upper surface of the ink recovery tray 50 slopes downward from the cleaning liquid receiving portion 51 toward the waste ink discharging portion 54. That is, the waste ink that has fallen onto the ink recovery tray 50 flows from one side in the longitudinal direction (the cleaning liquid receiving portion 51 side) toward the other side (the waste ink discharging portion 54 side). The direction in which the waste ink flows is indicated by the white arrow.

[0046] FIG. 10 is a plan view showing the positional relationship between the recording heads 17a to 17c that constitute the line heads 11Y to 11K and the ink recovery tray 50. As shown in FIG. 10, the ink recovery tray 50 shown in FIG. 8 is disposed opposite the recording heads 17a and 17b. On the other hand, the ink recovery tray 50 shown in FIG. 8 is disposed opposite the recording head 17c after being inverted 180°.

[0047] More specifically, in each of the ink recovery trays 50 facing the recording heads 17a and 17c, a common ink discharging portion 54 is formed at the boundary portion. And the flow direction of the waste ink in each ink recovery tray 50 is in the reverse direction (inward in the left - right direction in FIG. 10) toward the ink discharging portion 54.

[0048] In the maintenance unit 19, a set of three ink recovery trays 50 shown in FIG. 10 is arranged one by one for each of the four line heads 11Y to 11K, and a total of 12 ink recovery trays 50 are arranged.

[0049] FIG. 11 is a cross - sectional view (a cross - sectional view taken along the arrow BB in FIG. 8) of the cleaning liquid receiving portion 51 of the ink recovery tray 50 cut along the tray width direction. The cleaning liquid receiving portion 51 is a portion that receives the cleaning liquid supplied to the ink recovery tray 50. As shown in FIG. 11, the cleaning liquid receiving portion 51 has a V - shaped cross - section that slopes downward from both ends in the direction orthogonal to the longitudinal direction of the ink recovery tray 50 (the tray width direction, the direction of the arrow EE′ in FIG. 11) toward the central portion (the lowermost portion) 51a.

[0050] As shown in FIG. 10, the ink recovery tray 50 facing the recording heads 17a and 17b has a cleaning liquid receiving portion 51 facing the cleaning liquid supply portions 60 of the recording heads 17a and 17b. Therefore, the cleaning liquid can be dropped from the cleaning liquid supply portion 60 to the cleaning liquid receiving portion 51.

[0051] On the other hand, in the ink recovery tray 50 facing the recording head 17c, the cleaning liquid receiving portion 51 is located on the opposite side of the cleaning liquid supply portion 60. Therefore, a cleaning liquid supply mechanism 61 for dropping the cleaning liquid onto the cleaning liquid receiving portion 51 is provided separately from the cleaning liquid supply portion 60 of the recording head 17c.

[0052] As shown in FIGS. 8 and 9, the cleaning liquid diffusion portion 52 is formed between the cleaning liquid receiving portion 51 and the waste ink receiving portion 53. In the cleaning liquid diffusion portion 52, a pair of ribs 55 that taper and spread from the cleaning liquid receiving portion 51 side toward the waste ink receiving portion 53 side are formed. The end portion 55a on the upstream side (the cleaning liquid receiving portion 51 side) of each rib 55 extends to the central portion 51a of the cleaning liquid receiving portion 51. The end portion 55a on the downstream side (the waste ink receiving portion 53 side) of each rib 55 extends to the groove portions 53a and 53d of the waste ink receiving portion 53.

[0053] FIG. 12 is a cross-sectional view (a cross-sectional view taken along the arrow CC in FIG. 8) of the waste ink receiving portion 53 of the ink recovery tray 50 cut along the tray width direction. The waste ink receiving portion 53 is formed adjacent to the downstream side of the cleaning liquid diffusion portion 52 and faces the ink ejection surfaces F1 of the recording heads 17a to 17c. In the waste ink receiving portion 53, four rows of groove portions 53a to 53d extending along the downward gradient of the ink recovery tray 50 (the direction perpendicular to the paper surface of FIG. 12, the direction of the arrow DD' in FIG. 9) are formed.

[0054] The groove portions 53a to 53d are formed adjacent to each other and in parallel by having ridges 56 and valleys 57 arranged alternately along the tray width direction (the direction of the arrow EE'). The groove portions 53a to 53d are V-shaped in cross section.

[0055] The waste ink discharge portion 54 is formed adjacent to the downstream side of the waste ink receiving portion 53. An ink discharge hole 54a is provided at one end of the waste ink discharge portion 54. The waste ink discharge portion 54 has a downward gradient toward the ink discharge hole 54a. That is, the ink discharge hole 54a is provided at the lowermost part of the waste ink discharge portion 54.

[0056] Next, the flow of the cleaning liquid and the waste ink when the cleaning liquid is dropped onto the ink recovery tray 50 will be described. The cleaning liquid dropped from the cleaning liquid supply portion 60 (or the cleaning liquid supply mechanism 61) into the cleaning liquid receiving portion 51 gathers at the central portion 51a in the tray width direction along the V shape (see FIG. 11) of the cleaning liquid receiving portion 51. The cleaning liquid that has gathered at the central portion 51a in the tray width direction moves to the cleaning liquid diffusion portion 52 along the inclination of the ink recovery tray 50.

[0057] The cleaning liquid that has moved to the cleaning liquid diffusion portion 52 reaches the rib 55. A part of the cleaning liquid flows while spreading outward in the tray width direction along the rib 55. Since the end portion 55b on the downstream side (the waste ink receiving portion 53 side) of each rib 55 extends to the groove portions 53a, 53d, the cleaning liquid surely flows into the groove portions 53a, 53d on the outer side in the tray width direction along the rib 55.

[0058] Also, the protruding amount of the rib 55 is not large enough to block the cleaning liquid (about 1 to 3 mm). Therefore, a part of the cleaning liquid flows over the rib 55. Furthermore, a gap 58 is formed between the end portions 55a on the upstream side (the cleaning liquid receiving portion 51 side) of the two ribs 55. Thereby, a part of the cleaning liquid surely flows into the groove portions 53b, 53c on the inner side in the tray width direction through the gap 58.

[0059] According to the configuration of the present embodiment, by providing the cleaning liquid receiving portion 51 having a V-shaped cross section in the tray width direction on the ink recovery tray 50, the cleaning liquid can be gathered at the central portion 51a in the tray width direction regardless of the variation in the dropping position of the cleaning liquid.

[0060] Further, by providing a cleaning liquid diffusion part 52 in which a pair of ribs 55 that taper and spread from the cleaning liquid receiving part 51 side toward the waste ink receiving part 53 side are formed, the cleaning liquid collected at the central part 51a in the tray width direction can be surely spread to the outside in the tray width direction and flowed into the waste ink receiving part 53.

[0061] Also, by providing groove parts 53a to 53d in the waste ink receiving part 53, the cleaning liquid that has flowed into the waste ink receiving part 53 reaches the waste ink discharging part 54 along the groove parts 53a to 53d. Therefore, for example, compared with the case where the waste ink receiving part 53 has a single V-shaped form with a downward gradient toward the central part in the tray width direction, the cleaning liquid easily flows over the entire area of the waste ink receiving part 53.

[0062] Furthermore, since the groove parts 53a to 53d having a V-shaped cross section are continuously formed by alternately arranging the valley parts 57 and the ridge parts 56, the cleaning liquid easily moves over the ridge parts 56 between the groove parts 53a to 53d. Therefore, the entire area of the waste ink receiving part 53 can be efficiently cleaned with a small amount of cleaning liquid.

[0063] In this embodiment, four rows of groove parts 53a to 53d are formed, but the number of rows of the groove parts is not particularly limited, and may be two rows, three rows, or five or more rows. However, when the number of rows of the groove parts is too small, even if the inclination angle between the ridge part and the valley part of the groove part (the inclination angle of the V-shaped form) is the same, the depth of the groove part becomes large. As a result, it becomes difficult for the cleaning liquid to contact the waste ink adhering to the outside in the tray width direction of the groove part, and it becomes necessary to flow a large amount of cleaning liquid. Also, the vertical dimension of the ink recovery tray 50 becomes large.

[0064] On the other hand, if the number of rows of the groove portions is too large, even if the inclination angles between the ridge portions and the valley portions of the groove portions are the same, the depth of the groove portions becomes small. As a result, the waste ink receiving portion 53 becomes closer to being flat, making it difficult to control the flow of waste ink and cleaning liquid. Therefore, the number of rows of the groove portions is preferably about 3 to 5 rows, and it is preferable to form four rows of groove portions 53a to 53d as in the present embodiment. Further, the inclination angle between the ridge portion 56 and the valley portion 57 of each of the groove portions 53a to 53d is preferably about 3 to 5°.

[0065] Also, the groove portions 53b and 53c closest to the central portion 51a of the cleaning liquid receiving portion 51 can be made shallower than the groove portions 53a and 53d (the V-shaped angle is more obtuse than that of the groove portions 53a and 53d). By doing so, since the groove portions 53b and 53c where the cleaning liquid reaches the earliest are shallow, the cleaning liquid overflows from the groove portions 53b and 53c over the ridge portion 56 and easily spreads to the groove portions 53a and 53d on both sides. Note that it is not necessary to make the groove portions 53b and 53c shallower than the groove portions 53a and 53d over the entire area, and it is sufficient that at least the upstream side (the cleaning liquid receiving portion 51 side) is shallower than the groove portions 53a and 53d.

[0066] In addition, the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention. For example, the number and arrangement direction of the ink recovery trays 50 are not particularly limited, and may be appropriately determined according to the number of recording heads arranged on each of the line heads 11C to 11K.

Industrial Applicability

[0067] The present invention can be used in an inkjet recording apparatus including an ink recovery tray for receiving ink extruded from the ink ejection surface of a recording head. By using the present invention, it is possible to provide an inkjet recording apparatus capable of efficiently cleaning the ink that has fallen onto the ink recovery tray using a cleaning liquid.

Explanation of Reference Numerals

[0068] 9 Recording unit 11C~11K Line heads Recording heads 17a to 17c Ink ejection port 18 Maintenance unit 19 Wiper 35 Ink recovery tray 50 Cleaning liquid receiving part (Cleaning solution receiving part) 51 Cleaning liquid diffusion part (Cleaning solution diffusion part) 52 Waste ink receiving part 53 Groove parts 53a to 53d Waste ink discharge part 54 Ink discharge hole 54a Rib 55 Ridge part 56 Valley part 57 Cleaning liquid supply part (Cleaning solution supply part) 60 Cleaning liquid supply mechanism (Cleaning solution supply mechanism) 61 Printer (Inkjet recording apparatus) 100 Ink ejection surface F1 Paper (Recording medium) P

Claims

1. An ink recovery tray that is disposed opposite the recording head when executing a recovery operation of the recording head that discharges ink onto a recording medium, and recovers the ink extruded onto the ink discharge surface of the recording head; A cleaning liquid supply mechanism that supplies a cleaning liquid for cleaning the ink onto the ink recovery tray; In an inkjet recording apparatus comprising: The ink recovery tray: A cleaning liquid receiving portion that receives the cleaning liquid dropped from the cleaning liquid supply mechanism; A waste ink receiving portion that faces the ink discharge surface; A cleaning liquid diffusion portion disposed between the cleaning liquid receiving portion and the waste ink receiving portion; A waste ink discharge portion disposed adjacent to the opposite side of the waste ink receiving portion from the cleaning liquid diffusion portion; having, and having a downward gradient from the cleaning liquid receiving portion toward the waste ink discharge portion, A plurality of V-shaped groove portions in cross-sectional view extending along the downward gradient are formed in the waste ink receiving portion, In the cleaning liquid diffusion portion, a pair of ribs that taper and spread from the cleaning liquid receiving portion side toward the waste ink receiving portion side are formed. An inkjet recording apparatus characterized by this.

2. The cleaning liquid receiving portion has a V-shaped cross-sectional view with a downward gradient from both ends in the tray width direction orthogonal to the downward gradient toward the central portion, The inkjet recording apparatus according to claim 1, wherein the ends of the pair of ribs on the cleaning liquid receiving portion side extend to the central portion of the cleaning liquid receiving portion.

3. The inkjet recording apparatus according to claim 2, wherein a gap is formed between the ends of the pair of ribs on the cleaning liquid receiving portion side.

4. The inkjet recording apparatus according to claim 1, wherein the ends of the pair of ribs on the waste ink receiving portion side extend to the outermost groove portion in the tray width direction orthogonal to the downward slope among the plurality of groove portions.

5. Among the plurality of groove portions, the groove portion closest to the central portion in the tray width direction orthogonal to the downward slope of the cleaning liquid receiving portion is at least shallower on the cleaning liquid receiving portion side than the other groove portions. The inkjet recording apparatus according to claim 1.

6. The plurality of groove portions are formed adjacent to each other in parallel by alternately arranging ridge portions and valley portions along the tray width direction orthogonal to the downward slope, and the inclination angle between the ridge portion and the valley portion is 3 to 5°. The inkjet recording apparatus according to claim 1.

7. The recording head has a cleaning liquid supply portion for supplying the cleaning liquid to the ink ejection surface. The cleaning liquid supply portion also serves as the cleaning liquid supply mechanism, and the cleaning liquid receiving portion faces the cleaning liquid supply portion. The inkjet recording apparatus according to claim 1.

8. It has a wiper that moves along the ink ejection surface, and is provided with a maintenance unit that performs a recovery operation of the recording head by wiping the ink extruded onto the ink ejection surface with the wiper. The ink recovery tray is attached to the maintenance unit. The inkjet recording apparatus according to any one of claims 1 to 7.

Images