Liquid supply device and ink jet recording apparatus

Abstract

To uniformly supply liquid to a plurality of check valves.SOLUTION: A liquid supply device (cleaning liquid supply source 13) includes a flow path 13A, a pump 13P that supplies liquid (cleaning liquid) to the flow path 13A, and an opening / closing device 132 that opens / closes the flow path 13A. The flow path 13A includes a plurality of distribution flow paths 13D arranged in parallel between the pump 13P and the opening / closing device 132. Each of the plurality of distribution flow paths 13D includes: a branch flow path 13E branched from the distribution flow path 13D; a filter 131 that filters the liquid flowing through the branch flow path 13E; and a check valve 13V that is provided on the downstream side of the filter 131. In each of the distribution flow paths 13D, the fluid resistance of the filter 131 is greater than the release pressure of the check valve 13V, and is greater than the fluid resistance of the distribution flow path 13D when the flow path 13A is opened by the opening / closing device 132.SELECTED DRAWING: Figure 33

Description

Technical Field

[0001] The present invention relates to a liquid supply device and an inkjet recording device.

Background Art

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

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration disclosed in Patent Document 1, a cleaning liquid is supplied to a plurality of inkjet heads through a tube. However, if the cleaning liquid is left standing for a long time with the flow of the cleaning liquid stopped, bubbles may be generated in the cleaning liquid in the tube. If the cleaning liquid contains bubbles, the amount of cleaning liquid supplied to the plurality of inkjet heads may become non-uniform, or there is a risk that the cleaning liquid may expand like a balloon due to its viscosity and scatter.

[0005] As a countermeasure against bubbles, a configuration including a bubble trap that captures bubbles by utilizing the buoyancy acting on the bubbles and a check valve that discharges the air accumulated in the bubble trap is known (for example, Patent Document 2). However, in the configuration disclosed in Patent Document 1, a plurality of tubes are provided in parallel. When the configuration disclosed in Patent Document 2 is provided in each of the parallel tubes, since there are individual differences in the release pressure of the check valve, when the cleaning liquid is pressurized, there is a risk that the flow of the cleaning liquid will be biased toward the check valve with a low release pressure.

[0006] In view of the above circumstances, an object of the present invention is to supply liquid evenly from a plurality of check valves.

Means for Solving the Problems

[0007] To solve the above problems, a liquid supply device according to the present invention includes a flow path, a pump that supplies liquid to the flow path, and an opening / closing device that opens and closes the flow path. The flow path includes a plurality of distribution flow paths provided in parallel between the pump and the opening / closing device. Each of the plurality of distribution flow paths includes a branch flow path branched from the distribution flow path, a filter that filters the liquid flowing through the branch flow path, and a check valve provided on the downstream side of the filter. In each of the distribution flow paths, the fluid resistance of the filter is greater than the release pressure of the check valve and greater than the fluid resistance of the distribution flow path when the flow path is opened by the opening / closing device.

[0008] The liquid supply device may include a tank that supplies liquid to the flow path via the pump, and the flow path may be formed in a ring shape.

[0009] The liquid supply device may include a tank that supplies liquid to the flow path via the pump at an end portion on the upstream side of the flow path, and a waste liquid tank to which the liquid is discharged at an end portion on the downstream side of the flow path.

[0010] The liquid supply device may include a defoaming device that removes bubbles from the liquid in the flow path.

[0011] The liquid supply device may include a check valve between the branch points of the plurality of branch flow paths and the opening / closing device.

[0012] The liquid supply device may include the check valve in each of the plurality of distribution flow paths.

[0013] The liquid supply device includes a control unit that controls the pump and the opening / closing device. The control unit may drive the pump with the flow path closed by the opening / closing device and then open the flow path by the opening / closing device after stopping the pump.

[0014] The liquid supply device includes a control unit that controls the pump and the opening / closing device. The control unit may drive the pump with the flow path open by the opening / closing device.

[0015] An inkjet recording apparatus according to the present invention includes an inkjet head, a front liquid supply device, and a maintenance device that cleans the inkjet head using the cleaning liquid supplied from the liquid supply device.

Advantages of the Invention

[0016] According to the present invention, liquid can be supplied evenly from a plurality of check valves.

Brief Description of the Drawings

[0017]

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MODE FOR CARRYING OUT THE INVENTION

[0018] Hereinafter, the inkjet recording apparatus 1 according to an embodiment of the present invention will be described with reference to the drawings.

[0019] FIG. 1 is a perspective view showing the appearance of the image forming system 100. FIG. 2 is a front view schematically showing the internal configuration of the inkjet recording apparatus 1. FIG. 3 is a front view schematically showing the head unit 11 and the maintenance apparatus 30. FIG. 4 is a plan view schematically showing the head unit 11 and the wiper unit 32. FIG. 5 is a plan view schematically showing the cap unit 31. FIG. 6 is a cross-sectional view showing the inkjet head 12. Hereinafter, the front side (front side) of the inkjet recording apparatus 1 is defined as the front side of the paper surface in FIG. 2, and the left and right directions are described based on the direction of viewing the inkjet recording apparatus 1 from the front. In each figure, U, Lo, L, R, Fr, and Rr indicate up, down, left, right, front, and rear, respectively.

[0020] The image forming system 100 (see FIG. 1) includes a paper feeding device 110, an inkjet recording device 1, a drying device 120, and a post-processing device 130. The paper feeding device 110 stores thousands of sheets and supplies the sheets to the inkjet recording device 1. The inkjet recording device 1 forms an image on the sheet by an 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, stapling, and folding on the sheet conveyed from the drying device 120.

[0021] The inkjet recording device 1 (see FIG. 2) includes a rectangular parallelepiped main body housing 3. In the central portion inside the main body housing 3, a conveyance unit 7 that sucks and conveys the sheet in the Y direction is provided. Above the conveyance unit 7, an image forming unit 6 that discharges ink to form an image is provided. A paper feed port 8 for introducing the sheet from the paper feeding device 110 is provided on the right side surface of the main body housing 3. A discharge port 9 for discharging the sheet on which the image is formed to the drying device 120 is provided on the left side surface of the main body housing 3. Inside the main body housing 3, a conveyance path 10 is provided that extends from the paper feed port 8 through the gap between the conveyance unit 7 and the image forming unit 6 to the discharge port 9. A registration roller 18 is provided on the upstream side in the conveyance direction Y from the conveyance unit 7.

[0022] The conveying unit 7 includes an endless conveyor belt 21 and a suction unit 24. The conveyor belt 21 has a number of ventilation holes (not shown) and is wound around a driving roller 25 and a driven roller 22. The upper surface of the suction unit 24 has a number of ventilation holes (not shown) and is in contact with the inner surface of the conveyor belt 21. By the suction unit 24 sucking air through the ventilation holes of the conveyor belt 21 and the ventilation holes of the suction unit 24, the sheet is adsorbed to the conveyor belt 21. When the driving roller 25 is driven in the counterclockwise direction by a driving unit (not shown) including a motor and a reduction gear, the conveyor belt 21 rotates in the counterclockwise direction, and the sheet adsorbed to the conveyor belt 21 is conveyed in the Y direction.

[0023] The image forming unit 6 includes a plurality (four in this embodiment) of head units 11. The head unit 11 (see FIGS. 3 and 4) includes one or more (three in this embodiment) inkjet heads 12. An ink container 20 filled with black, cyan, magenta, and yellow inks is connected to each head unit 11.

[0024] The inkjet head 12 (see FIG. 6) includes a rectangular parallelepiped housing 12H having a longitudinal direction in the front-rear direction, a nozzle plate 14 provided at the bottom of the housing 12H, and a socket 12S to which a pipe for supplying ink is connected. The nozzle plate 14 includes a number of nozzles 14N arranged in the front-rear direction. The nozzle 14N includes a branch flow path 14B branched from the downstream side of the socket 12S and a discharge port 14A provided on the nozzle surface 14F which is the lower surface of the nozzle plate 14. The diaphragm 14V also serves as a part of the inner wall of the branch flow path 14B. A pressurizing element 14Z is provided on the diaphragm 14V. As the pressurizing element 14Z, a piezoelectric element, an electrostatic actuator, a heater, etc. are used. A drive circuit 12D for driving the pressurizing element 14Z is connected to the pressurizing element 14Z.

[0025] The control unit 2 (see FIG. 2) includes an arithmetic unit and a storage unit (not shown). The arithmetic unit is, for example, a CPU (Central Processing Unit). The storage unit includes storage media such as a ROM (Read Only Memory), a RAM (Random Access Memory), and an EEPROM (Electrically Erasable Programmable Read Only Memory). The arithmetic unit reads and executes the control program stored in the storage unit to perform various processes. Note that the control unit 2 may be realized by an integrated circuit that does not use software.

[0026] A display operation unit 19 is provided at the upper part of the main body housing 3 (see FIGS. 1 and 2). The display operation unit 19 includes a display panel, a touch panel laminated on the display panel, and a keypad (not shown). The control unit 2 causes the display panel to display a screen representing the operation menu, status, etc. of the inkjet recording apparatus 1, and controls each part of the inkjet recording apparatus 1 according to the operations detected by the touch panel and the keypad.

[0027] The basic image forming operation of the inkjet recording apparatus 1 is as follows. When an image forming job is input to the inkjet recording apparatus 1 from the display operation unit 19 or an external computer or the like, the paper feeding device 110 sends out a sheet to the conveyance path 10 through the paper feeding port 8, and the registration roller 18 whose rotation has been stopped corrects the skew of the sheet. When the registration roller 18 sends out the sheet to the conveyance unit 7 at a predetermined timing, the conveyance unit 7 sucks the sheet onto the conveyance belt 21 and conveys it in the Y direction. Ink is ejected from the inkjet head 12 onto the sheet to form an image. The sheet on which the image has been formed is conveyed to the drying device 120 through the discharge port 9.

[0028] [Maintenance Device] Next, the maintenance device 30 will be described. Since the four head units 11 (see FIG. 2) have the same configuration and the four maintenance devices 30 have the same configuration, hereinafter, one head unit 11 and one maintenance device 30 for maintaining this head unit 11 will be described.

[0029] [Head base] The head unit 11 includes a head base 11B (see FIGS. 3, 4, and 6) that supports the inkjet head 12. Three inkjet heads 12 are provided on the head base 11B in a staggered manner. The head base 11B is a generally rectangular plate-shaped member with the longitudinal direction being the front-rear direction. The head base 11B is provided with a through hole (not shown) into which the nozzle plate 14 of the inkjet head 12 is inserted. The lower surface of the head base 11B is a surface parallel to the nozzle surface 14F (hereinafter referred to as the parallel surface 11P). The nozzle surface 14F protrudes downward from the parallel surface 11P.

[0030] The maintenance device 30 (see FIG. 3) is provided on the side of the head unit 11 (in this embodiment, on the upstream side (right side) in the conveyance direction Y). The maintenance device 30 includes a cap unit 31, a wiper unit 32, and a cleaning liquid supply source 13.

[0031] [Cap unit] The cap unit 31 (see FIGS. 3 and 5) includes the same number of caps 72 as the inkjet heads 12 provided in the head unit 11 (three in this embodiment). The three caps 72 are arranged in a staggered manner, similar to the inkjet heads 12, and are supported by a frame body 71.

[0032] [Wiper unit] The wipe unit 32 (see FIGS. 3 and 4) includes a waste liquid tray 81, a blade 82, and a cleaning liquid supply unit 40. The waste liquid tray 81 has the same number of recesses 81U as the inkjet head 12 included in the head unit 11. The plurality of recesses 81U are arranged staggeredly in the same manner as the inkjet head 12. The blade 82 and the cleaning liquid supply unit 40 are provided in each of the recesses 81U.

[0033] [Head lifting device] FIG. 23 is a front view showing the operation of the maintenance device 30. The head lifting device 11L (see FIG. 4) is provided before and after 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 (see FIG. 23(A)) and the retracted position (see FIG. 23(B)). The image forming position is a position where the distance between the conveyance path 10 (the upper surface of the conveyance belt 21) along which the sheet is conveyed and the nozzle surface 14F is a predetermined distance suitable for image formation. The retracted position is a position above the image forming position and is a position where the head unit 11 does not interfere with the wipe unit 32 when the cap unit 31 and the wipe unit 32 are slid horizontally using the cap slide device 34 described later.

[0034] [Cap slide device] The cap slide device 34 (see FIG. 5) is provided before and after the frame 71 of the cap unit 31. The cap slide device 34 is composed of, for example, a ball screw, a belt drive device, etc. The cap slide device 34 slides the cap unit 31 between the home position (see FIG. 23(A)) and the maintenance position (see FIG. 23(F)). The home position is a position to the right of the head unit 11 located at the image forming position. The maintenance position is a position below the head unit 11 located at the retracted position.

[0035] [Wipe lifting device] The wipe lifting device 35 (see FIG. 4) is provided before and after the waste liquid tray 81 of the wipe unit 32. The wipe lifting device 35 is composed of, for example, a cam mechanism, a ball screw, etc. The wipe lifting device 35 raises and lowers the wipe unit 32 between a contact position (see FIG. 23(B)) and a separation position (see FIG. 23(E)). The contact position is the position where the waste liquid tray 81 contacts the cap 72. The separation position is the position where the waste liquid tray 81 is separated upward from the cap 72 by a predetermined distance.

[0036] When the wipe unit 32 is located at the contact position, since the wipe unit 32 is placed on the cap unit 31, by operating the cap slide device 34, the wipe unit 32 slides together with the cap unit 31 between the home position and the maintenance position. That is, the cap slide device 34 also functions as a wipe slide device that slides the wipe unit 32 between the home position and the maintenance position. When the wipe unit 32 is located at the separation position, by operating the cap slide device 34, the cap unit 31 slides alone between the home position and the maintenance position while leaving the wipe unit 32 at the home position.

[0037] [Wipe unit] Next, the configuration of the wipe unit 32 will be described in detail. FIG. 7 is a perspective view showing the wipe unit 32 and the cleaning liquid supply source 13. FIG. 8 is a perspective view showing the wipe unit 32. FIG. 9 is a perspective view showing the blade unit 90. FIG. 10 is a perspective view showing a cross section of the blade unit 90. FIG. 11 is a perspective view showing the protruding member 91 and the blade 82. FIG. 12 is a perspective view showing the protruding member 91.

[0038] The wipe unit 32 (see FIG. 7) includes a plurality (three in this embodiment) of blade units 90, a waste liquid tray 81, and a carriage 83. The blade unit 90 (see FIGS. 11 and 12) includes a blade 82, a protruding member 91, a holder 92, and a first biasing member 93.

[0039] [Blade] The blade 82 (see FIGS. 9 to 11) is a generally rectangular plate-like member having flexibility formed of resin or the like. The blade 82 is held by the holder 92 in a slightly rearwardly inclined posture with the front-rear direction as the thickness direction. The width of the blade 82 in the left-right direction is equal to or greater than the width of the nozzle surface 14F. A taper is provided at the upper portion of the blade 82 such that the thickness becomes thinner as it approaches the tip portion.

[0040] [Protrusion member] The protrusion member 91 (see FIGS. 9 to 12) is integrated with the blade 82. The protrusion member 91 includes a base portion 91B parallel to the blade 82, a first bent portion 911 bent rearward from the upper end portion of the base portion 91B, a second bent portion 912 bent upward from the rear end portion of the first bent portion 911, a rearwardly inclined portion 91T inclined more rearwardly than the second bent portion 912, and protrusions 91P protruding upward from both left and right end portions of the rearwardly inclined portion 91T and inclined rearwardly at the same inclination angle as the rearwardly inclined portion 91T.

[0041] The width of the base portion 91B in the left-right direction is equal to the width of the blade 82. The length of the base portion 91B in the up-down direction is shorter than the length of the blade 82 in the up-down direction. The base portion 91B is joined to the lower portion of the rear surface of the blade 82. The width of the first bent portion 911 and the second bent portion 912 in the left-right direction is equal to the width of the base portion 91B. The width of the rearwardly inclined portion 91T in the left-right direction is wider than the width of the base portion 91B. The left-right position of the protrusion 91P is determined such that the tip portion of the protrusion 91P can contact the left and right parallel surfaces 11P of the nozzle surface 14F.

[0042] On the rear surface of the base portion 91B, two wall portions 91C facing each other in the left-right direction are provided (see FIGS. 11 and 12). On the left surface of the left wall portion 91C, a shaft portion 91S protruding leftward is provided. On the right surface of the right wall portion 91C, a shaft portion 91S protruding rightward is provided.

[0043] A through-hole 91A penetrating downward is provided at the center in the left-right direction of the first bent portion 911 (see FIGS. 11 and 12). At least a part of the waste liquid W (a mixture of ink and cleaning liquid) flowing down along the rear surface of the blade 82 drops downward through the through-hole 91A.

[0044] [Fixing member] The fixing member 94 (see FIGS. 9 to 11) fixes the blade 82 to the protruding member 91. The lower part of the blade 82 is sandwiched between the base 91B of the protruding member 91 and the fixing member 94, and the fixing member 94 is fastened to the protruding member 91. Tapers (see FIGS. 9 and 12) with a width in the left-right direction becoming narrower downward are provided at the lower edge of the fixing member 94 and the lower edge of the protruding member 91. The waste liquid flowing down from the front surface of the blade 82 to the front surface of the fixing member 94 gathers at the center in the left-right direction along the lower edge of the fixing member 94 and the lower edge of the protruding member 91, and drops into the recess 81U of the waste liquid tray 81.

[0045] [Holder] The holder 92 (see FIGS. 9 to 11) holds the blade 82 via the protruding member 91. A shaft hole 92H into which the shaft portion 91S of the protruding member 91 is inserted is provided at the lower part of the holder 92. The protruding member 91 is swingable in the front-rear direction about the shaft portion 91S. The blade 82 swings together with the protruding member 91. The blade 82 and the protruding member 91 are provided on the holder 92 in a posture inclined with respect to the left-right direction so that the waste liquid W flows in either one direction in the left-right direction. In the illustrated example, the left end portion of the blade 82 is inclined so as to be slightly rearward of the right end portion, but it may be inclined in the opposite direction.

[0046] [First biasing member] The first biasing member 93 (see FIGS. 11 and 12) is, for example, a torsion coil spring and is wound around the shaft portion 91S. One end of the first biasing member 93 is engaged with the holder 92, and the other end is engaged with the protruding member 91. The first biasing member 93 biases the protruding member 91 in the counterclockwise direction in FIGS. 9 and 10 and in the clockwise direction in FIG. 11. In other words, the first biasing member 93 biases the blade 82 in a direction in which the tip of the blade 82 is pressed against the nozzle surface 14F. Note that the first biasing member 93 may be a leaf spring, a compression coil spring, or the like.

[0047] [Waste liquid tray] The waste liquid tray 81 (see FIGS. 7 and 8) is formed in a rectangular shape with the longitudinal direction in the front-rear direction as a whole. The waste liquid tray 81 includes three recesses 81U that are open at the upper side. The three recesses 81U are arranged in a staggered manner, similar to the inkjet head 12. The recesses 81U are formed in an elongated rectangular shape in the front-rear direction when viewed from above. The length of the recesses 81U in the front-rear direction is longer than that of the nozzle surface 14F, and the width of the recesses 81U in the left-right direction is wider than that of the nozzle surface 14F. The recesses 81U receive waste liquid including ink and cleaning liquid.

[0048] [Carriage] The carriage 83 (see FIGS. 7 to 10) is formed in a plate shape with the longitudinal direction in the front-rear direction. A groove 81G extending in the front-rear direction is provided between the left and right recesses 81U, and the carriage 83 is accommodated in the groove 81G. The length of the carriage 83 in the front-rear direction is shorter than the length of the groove 81G in the front-rear direction. The carriage 83 is slidable in the front-rear direction along the groove 81G.

[0049] Three blade units 90 are respectively accommodated in the three recesses 81U. The three blade units 90 are coupled to the carriage 83. The three blade units 90 are arranged on the carriage 83 such that when the carriage 83 is located at the rearmost position, the three blade units 90 are located behind the nozzle surface 14F.

[0050] [Carriage drive device] The waste liquid tray 81 is provided with a carriage drive device 36 (see FIG. 4). The carriage drive device 36 is composed of, for example, a belt drive device, a feed screw, etc., and slides the blade 82 by sliding the carriage 83 along the groove 81G. By sliding the blade 82 forward (an example of the advancing direction A of the wiping operation), a wiping operation is performed in which the blade 82 scrapes ink from the nozzle surface 14F. FIG. 7 shows the state where the blade 82 is located at the wiping operation start position. FIG. 8 shows the state where the blade 82 is located at the wiping operation end position.

[0051] [Receiving member] FIGS. 13 and 14 are perspective views showing the receiving member 84. The receiving member 84 is supported by the waste liquid tray 81 (see FIGS. 7, 8, and 10). The receiving member 84 is provided at the front end of each of the three recesses 81U. The receiving member 84 includes a front portion 84F facing the front surface of the blade 82, a ceiling portion 84T provided rearward from the upper end portion of the front portion 84F, and side wall portions 84W provided rearward from the left and right end portions of the front portion 84F. That is, the receiving member 84 is formed in a box shape with the rear side and the lower side open.

[0052] When the blade 82 reaches the foremost part of the recess 81U, the blade 82 is accommodated in the receiving member 84. At this time, the blade 82 is surrounded by the receiving member 84 from the front, above, and the left and right sides. Note that either one of the ceiling portion 84T and the side wall portion 84W may be provided.

[0053] [Cleaning liquid supply unit] Next, the cleaning liquid supply unit 40 will be described. FIG. 15 is a perspective view showing the cleaning liquid supply unit 40 and the blade unit 90. FIGS. 16 and 17 are right side views showing the cleaning liquid supply unit 40 and the blade unit 90. FIG. 18 is a perspective view showing the cleaning liquid supply unit 40. FIGS. 19 to 22 are perspective views showing the cross section of the cleaning liquid supply unit 40 and the cleaning liquid supply source 13. The cleaning liquid supply unit 40 includes a supply member 41, a link member 42, and a transfer member 44.

[0054] [Supply member] The supply member 41 includes a base end portion 51, an intermediate portion 52, and a housing portion 53 in order from the rear. The upper surface of the supply member 41 is flat and rectangular when viewed from above. The portion of the parallel surface 11P of the head base 11B that is behind the nozzle plate 14 also faces the upper surface of the supply member 41 and also serves as a pressing portion 11D that presses down the supply member 41. Note that the pressing portion 11D may be provided as a member separate from the head base 11B.

[0055] On the left side surface and the right side surface of the base end portion 51, arm support portions 51L protruding leftward and rightward are respectively provided (see FIG. 18). On the left and right arm support portions 51L, arm portions 51A protruding forward are respectively provided (see FIGS. 16 to 18). Shaft portions 51S protrude from the left side surface of the left arm portion 51A and the right side surface of the right arm portion 51A. Bosses 51B are provided behind the left and right shaft portions 51S.

[0056] The vertical thickness of the intermediate portion 52 is thinner than that of the base end portion 51 (see FIGS. 16 to 18). The lower surface of the intermediate portion 52 is flat. The lower surface of the housing portion 53 has a first inclined surface 531 and a second inclined surface 532 provided in front of the first inclined surface 531. The first inclined surface 531 is inclined such that the front side is lower than the rear side (see FIGS. 16 and 17). The second inclined surface 532 is inclined such that the front side is higher than the rear side. The first inclined surface 531 is continuous with the lower surface of the intermediate portion 52. Therefore, a wider space (hereinafter referred to as a non-contact space 52U) is formed below the intermediate portion 52 than below the housing portion 53.

[0057] The storage part 53 has a hollow structure having a storage space 53V for storing the cleaning liquid (see FIGS. 16 and 17). In the storage space 53V, it is desirable to provide a cleaning liquid holding member 53H (see FIGS. 21 and 22) for holding the cleaning liquid, such as a net-like member or a porous member. An inlet 53N (see FIGS. 15, 21, and 22) for taking in the cleaning liquid is provided on the upper surface of the storage part 53. An outlet 53E (see FIGS. 16 and 17) for discharging the cleaning liquid is provided on the lower surface of the storage part 53. The vertical thickness (the distance from the front end of the second inclined surface 532 to the upper surface) of the front end part of the storage part 53 is slightly larger than the distance from the lower surface of the head base 11B to the nozzle surface 14F.

[0058] [Link member] The link members 42 are provided on the left and right of the supply member 41 (see FIGS. 15 to 18). The lower parts of the left and right link members 42 are connected using a shaft 42S (see FIG. 18) having a longitudinal direction in the left-right direction. The shaft 42S is rotatably supported by the recess 81U of the waste liquid tray 81. Specifically, in the waste liquid tray 81, cutouts 81K are formed downward from the upper end parts of the left and right side wall parts of the recess 81U (see FIGS. 19 and 20). Both left and right end parts of the shaft 42S are supported by the cutouts 81K. The link member 42 is swingable around the shaft 42S.

[0059] Shaft holes 42H into which the shaft part 51S of the supply member 41 is inserted are provided in the upper parts of the left and right link members 42 (see FIGS. 16 to 18). The shaft holes 42H are arranged in front of the shaft 42S. A long hole 42L into which the boss 51B of the supply member 41 is inserted is provided behind the shaft hole 42H. The supply member 41 is swingable with respect to the link member 42 within the longitudinal range of the long hole 42L around the shaft part 51S (see FIGS. 16 and 17).

[0060] [Second biasing member] The link member 42 is provided with a second biasing member 43 (see FIG. 18). Specifically, the second biasing member 43 is a torsion coil spring and is wound around the shaft 42S. One end of the second biasing member 43 is engaged with the holder 92, and the other end is engaged with the link member 42 (see FIGS. 16 and 17). The second biasing member 43 biases the link member 42 in the clockwise direction in FIGS. 16 and 17. In other words, the second biasing member 43 biases the supply member 41 in the direction approaching the inkjet head 12. Note that the second biasing member 43 may be a leaf spring, a compression coil spring, or the like.

[0061] [Delivery member] A delivery member 44 is joined to the second inclined surface 532. The delivery member 44 has the same inclination angle as the second inclined surface 532. The delivery member 44 is a rectangular sheet-like member formed of resin or the like and has flexibility. The front end portion of the delivery member 44 protrudes forward of the front end portion of the housing portion 53. A discharge port 44A is provided in the delivery member 44 at a position corresponding to the discharge port 53E of the housing portion 53 (see FIG. 18).

[0062] [Outline of cleaning liquid supply source] A cleaning liquid supply source 13 (see FIGS. 7, 19 to 22) supplies cleaning liquid to the supply member 41. The cleaning liquid is a liquid mainly composed of water. The cleaning liquid supply source 13 includes a tank 13T, a pump 13P, a supply flow path 13C, and a support plate 13B. The cleaning liquid is stored in the tank 13T. The supply flow path 13C branches into three on the downstream side of the pump 13P. The branched supply flow paths 13C are each connected to a check valve 13V. The three check valves 13V are respectively arranged above the inlet 53N of the supply member 41. The supply flow path 13C and the check valve 13V are supported by the support plate 13B. The check valve 13V penetrates the support plate 13B, and the discharge port 15K of the check valve 13V protrudes from the lower surface of the support plate 13B.

[0063] Before and after the support plate 13B, a supply source lifting device 13L (see FIG. 7) is provided. The supply source lifting device 13L is composed of, for example, a cam mechanism, a ball screw, etc. The supply source lifting device 13L raises and lowers the support plate 13B between a supply position (see FIG. 23(A)) and a retracted position (see FIG. 23(B)). The supply position is the position where the discharge port 15K of the check valve 13V is inserted into the intake port 53N (see FIGS. 20 and 22). The retracted position is the position where the discharge port 15K of the check valve 13V retracts upward from the intake port 53N (see FIGS. 19 and 21).

[0064] On the lower surface of the support plate 13B, a convex portion 13BT protruding downward is provided at a position corresponding to the protruding portion 91P of the protruding member 91 (see FIGS. 19 to 22). Further, on the lower surface of the support plate 13B, convex portions 13BS protruding downward are provided on the left and right sides of the check valve 13V (see FIGS. 19 and 20).

[0065] [Outline of the operation of the wiper unit] Next, the outline of the operation of the wiper unit 32 will be described. FIG. 24 is a plan view showing the operation of the wiper unit 32. FIGS. 25 to 30 are right side views showing the operation of the wiper unit 32. Here, the outline of the operation of the wiper unit 32 will be described, and the operations of the protruding member 91 and the supply member 41 will be described later.

[0066] Hereinafter, the state shown in FIGS. 23(A) and 24(A) will be described as the initial state. In the initial state, the head unit 11 is located at the image forming position (see FIG. 23(A)), the cap unit 31 is located at the home position, the wiper unit 32 is located at the home position and the contact position, and the cleaning liquid supply source 13 is located at the supply position. The blade 82 is located at the wiper operation start position (see FIG. 24(A)). A predetermined amount of cleaning liquid is supplied from the cleaning liquid supply source 13 to the cleaning liquid supply unit 40. The control unit 2 executes the following processes at a predetermined timing. The predetermined timing is, for example, the timing when an increase in the viscosity of the ink in the nozzle 14N is expected, specifically, when a period in which no image forming job is executed continues for a predetermined period.

[0067] First, the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see Fig. 23(B)). Further, the control unit 2 operates the supply source lifting device 13L to raise the cleaning liquid supply source 13 to the retracted position.

[0068] Next, the control unit 2 operates the cap slide device 34 to slide the cap unit 31 to the maintenance position (see Figs. 23(C), 24(B), 25). At this time, since the wiper unit 32 is placed on the cap unit 31, the wiper unit 32 also slides to the maintenance position together with the cap unit 31. Next, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to the height at which the wiping operation is performed (hereinafter referred to as the wipe position) (see Figs. 23(D), 26).

[0069] Next, after the control unit 2 discharges a predetermined amount of ink from the inkjet head 12, it operates the carriage drive device 36 to slide the blade 82 forward along the nozzle surface 14F (see Figs. 24(C), 27, 28, 29). The blade 82 scrapes the cleaning liquid F bulging from the discharge port 44A (see Fig. 27) and advances along the nozzle surface 14F (see Figs. 28, 29). On the nozzle surface 14F, the residual ink K is diluted by the cleaning liquid F carried by the blade 82. The waste liquid containing the residual ink K and the cleaning liquid F is scraped by the blade 82 and falls into the recess 81U.

[0070] Next, the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see Figs. 23(C), 30). Next, the control unit 2 operates the carriage drive device 36 to return the blade 82 to the wipe operation start position (see Figs. 24(B), 25). Next, the control unit 2 operates the cap slide device 34 to slide the cap unit 31 and the wiper unit 32 to the home position (see Figs. 23(B), 24(A)).

[0071] Next, the control unit 2 operates the wiper lifting device 35 to raise the wiper unit 32 to the separated position (see Fig. 23(E)). Next, the control unit 2 operates the cap slide device 34 to slide the cap unit 31 to the maintenance position (see Figs. 23(F) and 24(D)). At this time, since the wiper unit 32 is separated from the cap unit 31, the wiper unit 32 remains at the home position, and only the cap unit 31 slides to the maintenance position.

[0072] Next, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to the height at which the nozzle surface 14F contacts the cap 72 (hereinafter referred to as the cap position) (see Fig. 23(G)). In this way, the cap 72 is attached to the nozzle surface 14F.

[0073] When executing an image forming job, the control unit 2 operates the head lifting device 11L to raise the head unit 11 to the retracted position (see Fig. 23(F)), operates the cap slide device 34 to slide the cap unit 31 to the home position (see Fig. 23(E)), and operates the wiper lifting device 35 to lower the wiper unit 32 to the contact position (see Fig. 23(B)). Then, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to the image forming position (see Fig. 23(A)) and executes the image forming job.

[0074] [Operations of the Protrusion Member and the Feeding Member] Next, the operations of the protrusion member 91 and the feeding member 41 will be described. Fig. 16 shows a state where the protrusion member 91 and the feeding member 41 are not pushed down (hereinafter referred to as the non-pushed-down state). On the other hand, Fig. 17 shows a state where the protrusion member 91 is pushed down by the parallel surface 11P or the convex portion 13BT, and the feeding member 41 is pushed down by the pushing portion 11D or the convex portion 13BS (hereinafter referred to as the pushed-down state). The first biasing member 93 biases the protrusion member 91 in the counterclockwise direction in Figs. 16 and 17. Also, the second biasing member 43 biases the link member 42 in the clockwise direction.

[0075] [Non - depressed state] When the wiper unit 32 is in the home position and the cleaning liquid supply source 13 has risen to the retracted position, it is in the non - depressed state (see Figs. 19, 21, 23(B), (E), (F), (G)). Also, when the wiper unit 32 is in the maintenance position and the head unit 11 has risen to the retracted position, it is also in the non - depressed state (see Fig. 23(C)).

[0076] [Depressed state] On the other hand, when the wiper unit 32 is in the home position and the cleaning liquid supply source 13 has descended to the supply position, it is in the depressed state (see Figs. 20, 22, 23(A)). Specifically, when the cleaning liquid supply source 13 descends from the non - depressed state (see Figs. 16, 19, 21) (see Figs. 17, 20, 22), the convex portion 13BT presses down the protruding portion 91P against the first biasing member 93, and the convex portion 13BS presses down the supply member 41 against the second biasing member 43. At this time, the discharge port 15K of the check valve 13V is inserted into the intake port 53N of the supply member 41 (see Fig. 22), and it becomes possible to supply the cleaning liquid from the cleaning liquid supply source 13 to the cleaning liquid supply unit 40.

[0077] Also, when the wiper unit 32 is in the maintenance position and the head unit 11 has descended to the wiper position, it is in the depressed state (see Fig. 23(D)). When the head unit 11 descends from the non - depressed state (see Fig. 16) (see Fig. 17), the parallel surface 11P presses down the protruding portion 91P against the first biasing member 93, and the pressing portion 11D presses down the supply member 41 against the second biasing member 43.

[0078] When transitioning from the non - depressed state to the depressed state, the protruding portion 91P is pushed down, causing the blade 82 to swing in the clockwise direction. Therefore, the inclination angle β of the front surface of the blade 82 with respect to the vertical line V in the depressed state (see Fig. 17) is larger than the inclination angle α in the non - depressed state (see Fig. 16). Also, when the supply member 41 is pushed down, the link member 42 swings in the counter - clockwise direction. Therefore, in the depressed state, the supply member 41 moves forward and downward compared to the non - depressed state.

[0079] Here, when paying attention to the tip of the blade 82, in the non-pressed state, the tip of the blade 82 is positioned below the first inclined surface 531 of the supply member 41. On the other hand, in the pressed state, relatively, the tip of the blade 82 moves rearward and downward, and the supply member 41 moves forward and downward. However, since the tip of the blade 82 enters the non-contact space 52U below the intermediate portion 52 of the supply member 41, interference between the blade 82 and the supply member 41 is avoided.

[0080] [Wiper operation] Next, the wiper operation will be described in detail. When the head unit 11 rises to the retracted position and the wiper unit 32 slides to the maintenance position (see FIGS. 23(C), 24(B), and 25), the protruding member 91 and the supply member 41 are in the non-pressed state (see FIG. 16). At this time, the rear end surface of the nozzle plate 14 and the front end surface of the supply member 41 are separated from each other in the front-rear direction by a distance D (see FIG. 25). The cleaning liquid F bulges from the discharge port 44A of the transfer member 44 (see FIG. 18) (see FIG. 25). Residual ink K adheres to the nozzle surface 14F (see FIG. 25).

[0081] Next, the control unit 2 operates the head lifting device 11L to lower the head unit 11 to the wiper position (see FIGS. 23(D) and 26). Then, since the parallel surface 11P presses down the protruding member 91 and the supply member 41, the protruding member 91 and the supply member 41 are in the pressed state (see FIG. 17). At this time, the blade 82 swings from the inclination angle α to the inclination angle β. Also, since the supply member 41 moves forward, the distance between the front end surface of the supply member 41 and the rear end surface of the nozzle plate 14 is reduced. At this time, the front end surface of the supply member 41 and the rear end surface of the nozzle plate 14 may come into contact. Further, the transfer member 44 moves below the nozzle surface 14F, and at least the front end portion of the upper surface of the transfer member 44 comes into contact with the nozzle surface 14F, so that the step between the second inclined surface 532 and the nozzle surface 14F is eliminated.

[0082] Next, the control unit 2 causes the inkjet head 12 to eject a predetermined amount of ink. By this operation, the ink with increased viscosity is discharged from the nozzles 14N. Next, the control unit 2 operates the carriage drive device 36 to slide the blade 82 forward along the nozzle surface 14F (see Fig. 24(C)). The blade 82 scrapes the cleaning liquid F bulging from the discharge port 44A (see Fig. 27), moves along the lower surface of the delivery member 44 to the nozzle surface 14F, and then advances along the nozzle surface 14F (see Fig. 28). In Figs. 27 and 28, the tip of the blade 82 overlaps the supply member 41 and the nozzle plate 14, but actually, the tip of the blade 82 is bent backward.

[0083] When the blade 82 advances along the nozzle surface 14F, since the blade 82 advances with the protruding member 91 in contact with the parallel surface 11P, the inclination angle of the blade 82 is kept constant. Therefore, the blade 82 is pressed against the nozzle surface 14F with a constant load. Also, the blade 82 is pressed against the nozzle surface 14F mainly by the elastic force of the first biasing member 93. The elastic force of the first biasing member 93 is adjusted to minimize the deflection of the blade 82.

[0084] On the nozzle surface 14F, the residual ink K is diluted by the cleaning liquid F carried by the blade 82. The waste liquid containing the residual ink K and the cleaning liquid F is scraped by the blade 82 and flows down along the front and rear surfaces of the blade 82. The waste liquid W flowing down along the rear surface of the blade 82 passes through the through-hole 91A of the protruding member 91 and drops into the recess 81U (see Fig. 11). Also, the waste liquid W flowing down along the front surface of the blade 82 is collected at the center in the lateral direction along the front surface of the fixing member 94 and the lower edges of the fixing member 94 and the protruding member 91, and drops into the recess 81U.

[0085] In parallel with the blade 82 passing through the front end of the nozzle surface 14F (see Fig. 29), the control unit 2 operates the head lifting device 11L to lift the head unit 11 to the retracted position (see Fig. 30). At this time, since the head base 11B also rises, the protruding member 91 and the supply member 41 return to the non-pressed state. Further, as the blade 82 separates from the nozzle surface 14F, the bending deformation of the blade 82 is eliminated. By this operation, the waste liquid W is discharged from the blade 82 toward the receiving member 84. The waste liquid W received by the receiving member 84 flows downward along the inner surface of the receiving member 84 and falls into the recess 81U.

[0086] If the configuration for changing the inclination angle of the blade 82 (such as the protruding member 91, the holder 92, the first biasing member 93, etc.) is not provided, the blade 82 is pressed against the nozzle surface 14F solely by the elastic force due to the bending deformation of the blade 82 itself. Therefore, when the tip of the blade 82 passes through the front end of the nozzle surface 14F, the bending of the blade 82 is rapidly eliminated, and the waste liquid W may scatter. On the other hand, in the present embodiment, the bending of the blade 82 is suppressed to a smaller amount compared to the case where the configuration for changing the inclination angle of the blade 82 is not provided. Further, since the restoration of the inclination of the blade 82 is performed in parallel with the elimination of the bending deformation, the waste liquid W is mainly discharged forward and received by the receiving member 84, and the scattering of the waste liquid W is suppressed.

[0087] [Details of the cleaning liquid supply source] As described above, when the wiper unit 32 is located at the home position and the cleaning liquid supply source 13 descends to the supply position, it is in the pressed state (see Figs. 20, 22, 23(A)). At this time, the discharge port 15K of the check valve 13V is inserted into the inlet 53N of the supply member 41 (see Fig. 22), and it becomes possible to supply the cleaning liquid from the cleaning liquid supply source 13 to the cleaning liquid supply unit 40. Here, the configuration of the cleaning liquid supply source 13 (an example of a liquid supply device) will be described in detail.

[0088] FIG. 31 is a plan view showing the cleaning liquid supply source 13. FIG. 32 is a cross-sectional view showing the check valve 13V. FIG. 33 is a piping system diagram showing the cleaning liquid supply source 13. The cleaning liquid supply source 13 according to the present embodiment includes a flow path 13A, a pump 13P that supplies a liquid (for example, cleaning liquid) to the flow path 13A, and an opening / closing device 132 that opens and closes the flow path 13A. The flow path 13A includes a plurality of distribution flow paths 13D provided in parallel between the pump 13P and the opening / closing device 132. Each of the plurality of distribution flow paths 13D includes a branch flow path 13E that branches from the distribution flow path 13D, a filter 131 that filters the liquid flowing through the branch flow path 13E, and a check valve 13V provided on the downstream side of the filter 131. In each of the distribution flow paths 13D, the fluid resistance of the filter 131 is greater than the release pressure of the check valve 13V and greater than the fluid resistance of the distribution flow path 13D when the flow path 13A is opened by the opening / closing device 132. Specifically, it is as follows. Hereinafter, the upstream side and the downstream side mean the upstream side and the downstream side in the supply direction of the cleaning liquid.

[0089] [Flow path] The flow path 13A (see FIG. 31) is attached to the support plate 13B. The flow path 13A is composed of three sections: a supply flow path 13C, a plurality of parallel distribution flow paths 13D, and a recovery flow path 13F in order from the upstream side. The plurality of distribution flow paths 13D branch from the supply flow path 13C and merge into the recovery flow path 13F. The number of distribution flow paths 13D is equal to the number of cleaning liquid supply members 41 provided in the wiper unit 32 (three in this embodiment).

[0090] Joint 13G is provided at both ends of the flow path 13A. A relay flow path 13H is provided between the two joints 13G. That is, the flow path 13A is formed in an annular shape as a whole. A tank 13T for storing the cleaning liquid and a pump 13P for supplying the cleaning liquid from the tank 13T to the flow path 13A are provided in the relay flow path 13H.

[0091] [Opening / closing device] The recovery flow path 13F is provided with an opening / closing device 132. The opening / closing device 132 may have any configuration as long as it can open and close the recovery flow path 13F. For example, it may be composed of an eccentric cam and a reaction plate facing each other across the recovery flow path 13F, or it may be a solenoid valve or the like (not shown).

[0092] [Branch flow path] Each of the distribution flow paths 13D is provided with a branch flow path 13E branched from the distribution flow path 13D. In the branch flow path 13E, a filter 131 and a check valve 13V are provided in order from the upstream side.

[0093] [Check valve] The check valve 13V (see FIG. 32) includes an inner cylinder part 15A, an outer cylinder part 15B, a ceiling part 15C, a ball 15E, and a spring 15F. The inner cylinder part 15A is accommodated inside the outer cylinder part 15B. The inner cylinder part 15A has a discharge port 15K. The ceiling part 15C is integrated with the outer cylinder part 15B and closes the upper end part of the outer cylinder part 15B. The space between the inner peripheral surface of the outer cylinder part 15B and the outer peripheral surface of the inner cylinder part 15A is sealed by an O-ring 15G. The space between the upper end part of the inner cylinder part 15A and the ceiling part 15C is sealed by an O-ring 15G. The spring 15F is disposed inside the inner cylinder part 15A. The ball 15E is pushed upward by the spring 15F and pressed against the O-ring 15G between the inner cylinder part 15A and the ceiling part 15C. A through hole 15L penetrating in the vertical direction is provided at the center of the ceiling part 15C. The branch flow path 13E is connected to the through hole 15L.

[0094] [Filter] A filter 131 is provided between the ceiling part 15C and the ball 15E. The filter 131 is formed in a plate shape using a non-woven fabric, a woven fabric, paper, a porous body, or the like. The check valve 13V is fastened to the support plate 13B using a screw 15J via a fixing member 15H that covers the outer cylinder part 15B.

[0095] In the above configuration, when supplying the cleaning liquid to the supply member 41 of the cleaning liquid supply unit 40 through the branch flow path 13E, the control unit 2 closes the recovery flow path 13F by the opening / closing device 132. Then, the pressure in the branch flow path 13E rises and the check valve 13V is released, and the cleaning liquid is supplied through the check valve 13V. On the other hand, when the recovery flow path 13F is opened by the opening / closing device 132, since the fluid resistance of the distribution flow path 13D is lower than that of the branch flow path 13E, the cleaning liquid flows along the distribution flow path 13D and merges into the recovery flow path 13F. In this case, no cleaning liquid is supplied to the branch flow path 13E.

[0096] However, since there are individual differences in the spring constant of the spring 15F of the check valve 13V, there are also individual differences in the release pressure of the check valve 13V. In the conventional configuration without the filter 131, the cleaning liquid preferentially flows through the branch flow path 13E having the check valve 13V with the lowest release pressure, and it becomes difficult for the cleaning liquid to flow through the other branch flow paths 13E. Then, the supply amount of the cleaning liquid to the plurality of supply members 41 provided in the wiper unit 32 becomes non-uniform.

[0097] Therefore, in the present embodiment, a filter 131 is provided between the branch point of the branch flow path 13E and the check valve 13V, and in addition, the fluid resistance of the filter 131 is larger than the release pressure of the check valve 13V. When using filters 131 of the same material and the same specifications, the variation in the fluid resistance of the filters 131 is smaller than the variation in the release pressure of the check valves 13V, so the pressure rises substantially uniformly in the plurality of branch flow paths 13E. Since the pressure of the cleaning liquid passing through the filter 131 is larger than the release pressure of the check valve 13V, even if there are individual differences in the release pressure of the check valve 13V, a uniform amount of cleaning liquid is supplied through each check valve 13V.

[0098] Note that it is desirable that the fluid resistance of the filter 131 is three times or more the release pressure of the check valve 13V. Also, it is desirable that the fluid resistance of the filter 131 is two times or more the fluid resistance of the distribution flow path 13D when the recovery flow path 13F is opened by the opening / closing device 132.

[0099] [Defoaming device] It is desirable that a degassing device 134 be provided in the recovery flow path 13F. The degassing device 134 may be configured, for example, to remove bubbles from the cleaning liquid by providing a gas-liquid separation membrane in a part of the recovery flow path 13F and reducing the pressure outside the gas-liquid separation membrane (not shown). Alternatively, the degassing device 134 may be configured to provide a liquid tank (bubble trap) for temporarily storing the cleaning liquid in the recovery flow path 13F and releasing bubbles from the liquid surface in the liquid tank to the atmosphere (not shown).

[0100] [Check valve in the recovery flow path] It is desirable that a check valve 135 be provided in the recovery flow path 13F. The check valve 135 has the same structure as the check valve 13V in the branch flow path 13E, but does not have a filter 131.

[0101] Next, the operation of the cleaning liquid supply source 13 will be described. When the discharge port 15K of the check valve 13V is inserted into the inlet 53N of the supply member 41 in the pressed state (see FIGS. 20, 22, and 23(A)), the control unit 2 closes the recovery flow path 13F by the opening / closing device 132. At this time, the pressure in the recovery flow path 13F increases, but since the check valve 135 is provided, the backflow of the cleaning liquid does not occur.

[0102] Next, the control unit 2 drives the pump 13P to supply the cleaning liquid to the supply flow path 13C. Then, the pressure in the distribution flow path 13D increases, but since the recovery flow path 13F is closed, the cleaning liquid flows from the distribution flow path 13D into the branch flow path 13E. Since the fluid resistance of the filter 131 is greater than the release pressure of the check valve 13V, the pressure increases uniformly in the plurality of branch flow paths 13E, and a uniform amount of cleaning liquid is supplied through each check valve 13V. After driving the pump 13P for a predetermined time, the control unit 2 stops the pump 13P.

[0103] Here, if the pump 13P is left stopped, the release pressure of the check valve 13V and the pressure in the distribution channel 13D transition to an equilibrium state. If the equilibrium state is disrupted by vibration or the like, the cleaning liquid will leak from the check valve 13V. Therefore, after the pump 13P stops, the control unit 2 opens the recovery channel 13F with the opening / closing device 132 to reduce the pressure in the recovery channel 13F. By this process, leakage of the cleaning liquid from the check valve 13V can be prevented.

[0104] Next, the control unit 2 drives the pump 13P with the recovery channel 13F open by the opening / closing device 132. By this operation, the cleaning liquid circulates in the channel 13A, and bubbles are removed from the cleaning liquid by the defoaming device 134. Note that the circulation of the cleaning liquid may be performed before the supply of the cleaning liquid or may be performed periodically.

[0105] According to the liquid supply device (cleaning liquid supply source 13) according to the present embodiment described above, the channel 13A, a pump 13P that supplies a liquid (cleaning liquid) to the channel 13A, and an opening / closing device 132 that opens and closes the channel 13A are provided. The channel 13A includes a plurality of distribution channels 13D provided in parallel between the pump 13P and the opening / closing device 132. Each of the plurality of distribution channels 13D includes a branch channel 13E that branches from the distribution channel 13D, a filter 131 that filters the liquid flowing through the branch channel 13E, and a check valve 13V provided on the downstream side of the filter 131. In each of the distribution channels 13D, the fluid resistance of the filter 131 is greater than the release pressure of the check valve 13V and greater than the fluid resistance of the distribution channel 13D when the channel 13A is opened by the opening / closing device 132. According to this configuration, the liquid can be supplied evenly from the plurality of check valves 13V.

[0106] Further, according to the liquid supply device according to the present embodiment, a tank 13T that supplies a liquid to the channel 13A via the pump 13P is provided, and the channel 13A is formed in a ring shape. According to this configuration, the consumption of the liquid can be suppressed.

[0107] Also, according to the liquid supply device according to the present embodiment, a degassing device 134 for removing bubbles from the liquid is provided in the flow path 13A. According to this configuration, it is possible to suppress insufficient supply of the liquid due to the remaining bubbles.

[0108] Also, according to the liquid supply device according to the present embodiment, a check valve 135 is provided between the branch point of the plurality of branch flow paths 13E and the opening / closing device 132. According to this configuration, when the flow path 13A is closed by the opening / closing device 132, it is possible to prevent the backflow of the liquid.

[0109] Also, according to the liquid supply device according to the present embodiment, a control unit 2 for controlling the pump 13P and the opening / closing device 132 is provided. The control unit 2 drives the pump 13P in a state where the flow path 13A is closed by the opening / closing device 132, and opens the flow path 13A by the opening / closing device 132 after stopping the pump 13P. According to this configuration, it is possible to prevent the leakage of the liquid due to vibration or the like.

[0110] Also, according to the liquid supply device according to the present embodiment, a control unit 2 for controlling the pump 13P and the opening / closing device 132 is provided. The control unit 2 drives the pump 13P in a state where the flow path 13A is opened by the opening / closing device 132. According to this configuration, it is possible to promote the removal of bubbles by the circulation of the liquid.

[0111] Also, according to the inkjet recording device 1 according to the present embodiment, an inkjet head 12, a liquid supply device, and a maintenance device 30 for cleaning the inkjet head 12 using the cleaning liquid supplied from the liquid supply device are provided. According to this configuration, it is possible to prevent the ink from dropping from the inkjet head 12.

[0112] The above embodiment may be modified as follows.

[0113] [First Modification Example] FIG. 34 is a piping system diagram showing the cleaning liquid supply source 13. The liquid supply device according to this modified example includes a tank 13T that supplies liquid to the flow path 13A via a pump 13P at the upstream end of the flow path 13A, and a waste liquid tank 133 where the liquid is discharged at the downstream end of the flow path 13A. In this modified example, the joints 13G are not connected by the relay flow path 13H. The upstream joint 13G is connected to the tank 13T and the pump 13P, and the downstream joint 13G is connected to the waste liquid tank 133. That is, the cleaning liquid flows along the one-way flow path 13A from the tank 13T to the waste liquid tank 133. Also according to this modified example, the liquid can be supplied evenly from the plurality of check valves 13V.

[0114] [Second Modified Example] FIG. 35 is a piping system diagram showing the cleaning liquid supply source 13. The liquid supply device according to this modified example includes a check valve 135 in each of the plurality of distribution flow paths 13D. With this configuration as well, when the flow path 13A is closed by the opening / closing device 132, the backflow of the liquid can be prevented.

Explanation of Reference Numerals

[0115] 1 Inkjet recording apparatus 2 Control unit 12 Inkjet head 13 Cleaning liquid supply source (liquid supply device) 13A Flow path 13P Pump 132 Opening / closing device 13D Distribution flow path 13E Branch flow path 131 Filter 13V Check valve 13T Tank 133 Waste liquid tank 134 Defoaming device 30 Maintenance device

Claims

1. A flow path, a pump for supplying liquid to the flow path, and an opening / closing device for opening and closing the flow path, wherein the flow path includes a plurality of distribution flow paths provided in parallel between the pump and the opening / closing device, each of the plurality of distribution flow paths includes a branch flow path branched from the distribution flow path, a filter for filtering the liquid flowing through the branch flow path, and a check valve provided on the downstream side of the filter, in each of the distribution flow paths, the fluid resistance of the filter is greater than the release pressure of the check valve and greater than the fluid resistance of the distribution flow path when the flow path is opened by the opening / closing device. A liquid supply device characterized by this.

2. comprising a tank for supplying liquid to the flow path via the pump, wherein the flow path is formed in a ring shape. The liquid supply device according to Claim 1.

3. comprising a tank for supplying liquid to the flow path via the pump at an upstream end of the flow path, and comprising a waste liquid tank for discharging liquid at a downstream end of the flow path. The liquid supply device according to Claim 1.

4. The liquid supply device according to Claim 2, further comprising a defoaming device for removing bubbles from the liquid in the flow path.

5. The liquid supply device according to any one of Claims 1 to 4, further comprising a check valve between a branch point of the plurality of branch flow paths and the opening / closing device.

6. The liquid supply device according to Claim 5, further comprising the check valve in each of the plurality of distribution flow paths.

7. A control unit for controlling the pump and the opening / closing device is provided. The liquid supply device according to claim 1, wherein the control unit drives the pump with the flow path closed by the opening / closing device and then opens the flow path by the opening / closing device after stopping the pump.

8. A control unit for controlling the pump and the opening / closing device is provided. The liquid supply device according to claim 4, wherein the control unit drives the pump with the flow path opened by the opening / closing device.

9. An inkjet head, The liquid supply device according to claim 1, An inkjet recording apparatus comprising: a maintenance device for cleaning the inkjet head using the cleaning liquid supplied from the liquid supply device.

Images