JP2023149934A - liquid discharge device - Google Patents

Abstract

To provide a liquid discharge device to be downsized in a configuration that cleaning liquid can be supplied from a cleaning liquid main tank to a cleaning liquid sub-tank.SOLUTION: A liquid discharge device 100 includes: a tank 181 storing liquid; a head 38 having a nozzle 38A discharging liquid supplied from the tank 181; a cleaning liquid main tank 76A storing cleaning liquid; a cleaning liquid sub-tank 76B connected to the cleaning liquid main tank 76A; a first flow channel 183 and a second flow channel 184 connecting the tank 181 and the head 38; a third flow channel 301 connecting the tank 181 and the cleaning liquid sub-tank 76B; a positive pressure pump 191 applying pressure to liquid in a direction toward the head 38 in the first flow channel 183; and a negative pressure pump 193 connected to the third flow channel 301 and making the tank 181 and the cleaning liquid sub-tank 76B negative pressure.SELECTED DRAWING: Figure 9

Description

The present invention relates to a liquid ejection device that ejects liquid stored in a tank from a head.

2. Description of the Related Art As a liquid ejecting device that ejects ink from a head, for example, an inkjet plotter device described in Patent Document 1 is known. In the plotter device of Patent Document 1, cleaning liquid is supplied to the head and ink is supplied to the head by switching between the ink flow path and the cleaning liquid flow path for one suction pump that sucks the inside of the cap. ing.

Japanese Patent Application Publication No. 2001-138543

Even when the head is not capped, ink may be supplied or circulated from the ink tank to the head, or cleaning liquid may be supplied from the cleaning liquid tank to the maintenance mechanism. In such a case, for example, if a pump is provided for each of the ink tank and the cleaning liquid tank, there is a problem that the apparatus becomes larger.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a liquid discharging device that can be miniaturized and has a configuration in which cleaning liquid can be supplied from a cleaning liquid main tank to a cleaning liquid sub-tank. be.

A liquid ejection device according to the present invention includes: a tank for storing liquid; a head having a nozzle for ejecting the liquid supplied from the tank; and a cleaning liquid main tank for storing cleaning liquid.
a cleaning liquid sub-tank connected to the cleaning liquid main tank; a first flow path and a second flow path connecting the tank and the head; a third flow path connecting the tank and the cleaning liquid sub-tank; A positive pressure pump that applies pressure to the liquid in a direction toward the head in one flow path, and a negative pressure pump that is connected to the third flow path and creates negative pressure in the tank and the cleaning liquid sub-tank. .

When the inside of the cleaning liquid sub-tank becomes negative pressure by the negative pressure pump, the cleaning liquid is supplied from the cleaning liquid main tank to the cleaning liquid sub-tank by this negative pressure. On the other hand, when a pressure difference is generated between the head and the tank by the positive pressure pump and the negative pressure pump, the liquid circulates between the head and the tank through the first flow path and the second flow path due to this pressure difference. In this way, the negative pressure pump is used for both cleaning liquid supply and liquid circulation, so compared to the case where a negative pressure pump for liquid circulation is provided separately from the negative pressure pump for cleaning liquid supply, the liquid The discharge device is miniaturized.
[Effect]
Liquid is suppressed from flowing into the third channel from the tank.

According to the present invention, the apparatus is miniaturized in a configuration in which the cleaning liquid can be supplied from the cleaning liquid main tank to the cleaning liquid sub-tank.

FIG. 1 is an external perspective view of an image recording apparatus 100 according to an embodiment of the present invention. FIG. 2 is a sectional view taken along II-II in FIG. 1, showing a state in which the head 38 is in the recording position, the first support mechanism 51 is in the first posture, and the maintenance mechanism 60 is in the standby position. . FIG. 3 is a sectional view showing a state in which the upper housing 31 in FIG. 2 is in an open position. FIG. 4 is a bottom view of the head 38. FIG. 5 is a perspective view of the maintenance mechanism 60. FIG. 6 is a bottom view of the maintenance mechanism 60. FIG. 7 is a cross-sectional view of the liquid flow path 153 of the support base 61 taken along a plane parallel to the flow direction of the liquid flow path 153. FIG. 8 is a cross-sectional view of the caps 62A, 62B, and 62C in the maintenance position. FIG. 9 is a schematic diagram showing the ink circuit 113. FIG. 10 is a block diagram of the image recording apparatus 100. FIG. 11 is a sectional view taken along II-II in FIG. 1, showing a state in which the head 38 is in the capped position, the first support mechanism 51 is in the first posture, and the maintenance mechanism 60 is in the maintenance position. show. FIG. 12 is a cross-sectional view taken along II-II in FIG. 1, showing a state in which the head 38 is in the wiping position, the first support mechanism 51 is in the first posture, and the maintenance mechanism 60 is in the wiping position. show. FIG. 13 is a sectional view taken along the line II-II in FIG. Indicates a state where the position is FIG. 14 is a sectional view taken along II-II in FIG. 1, showing a state in which the head 38 is in the recording position, the first support mechanism 51 is in the second posture, and the maintenance mechanism 60 is in the standby position. . FIG. 15 is a flowchart showing the empty suction process and the cleaning liquid replenishment process. FIG. 16 is a flowchart showing the liquid circulation process.

Preferred embodiments of the present invention will be described below. Note that this embodiment is only one embodiment of the present invention, and it goes without saying that the embodiment can be modified without changing the gist of the present invention. Further, in the following description, the progress from the starting point of the arrow to the ending point is expressed as the direction, and the coming and going on the line connecting the starting point and the ending point of the arrow is expressed as the direction. In addition, in the following description, the vertical direction 7 is defined based on the state in which the image recording device 100 is installed so that it can be used (the state in FIG. 1), and the side where the discharge port 33 is provided is the near side (the front side). ), a front-rear direction 8 is defined, and a left-right direction 9 is defined when the image recording apparatus 100 is viewed from the front side (front side).

[Exterior configuration of image recording device 100]
The image recording apparatus 100 (an example of a liquid ejecting apparatus) shown in FIG. 1 records an image on a sheet S forming a roll body 37 (see FIG. 2) using an inkjet recording method.

As shown in FIG. 1, the image recording device 100 includes a housing 30. The housing 30 includes an upper housing 31 and a lower housing 32. The upper housing 31 and the lower housing 32 have a generally rectangular parallelepiped shape as a whole, and are large enough to be placed on a tabletop. That is, the image recording apparatus 100 is suitable for use while being placed on a tabletop. Of course, the image recording apparatus 100 may be used while being placed on the floor or on a rack.

As shown in FIG. 2, the housing 30 is partitioned from the outside into an internal space 31A inside an upper housing 31 and an internal space 32A inside a lower housing 32.

As shown in FIGS. 2 and 3, the upper housing 31 is rotatably supported by the lower housing 32. The upper housing 31 is rotatable between a closed position shown in FIG. 2 and an open position shown in FIG. 3 around a rotation shaft 15 provided at the rear lower end and extending in the left-right direction 9.

As shown in FIG. 1, a slit-shaped discharge port 33 that is long in the left-right direction 9 is formed on the front surface 32F of the lower housing 32. A sheet S (see FIG. 2) on which an image has been recorded is discharged from the discharge port 33.

An operation panel 44 is provided on the front surface 31F of the upper housing 31. The user performs input on the operation panel 44 to operate the image recording apparatus 100 or confirm various settings. The operation panel 44 has a display section 44A. The display section 44A displays that the ink tank 34 is attached to the mounting case 110, that the storage liquid tank 11 is attached to the mounting case 110, and that the waste liquid tank 77 is to be replaced.

[Internal configuration of image recording device 100]
As shown in FIG. 2, the internal spaces 31A and 32A include a holder 35, a tensioner 45, a pair of conveying rollers 36, a pair of conveying rollers 40, a head 38, a first support mechanism 51, a heater 39, a support section 46, a second A support mechanism 52, a CIS 25, a cutter unit 26, an ink tank 34, a cleaning liquid tank 76, a waste liquid tank 77, a maintenance mechanism 60, and a wiper cleaning mechanism 80 are arranged. Although not shown in FIG. 2, a controller 130 (see FIG. 10) is arranged in the internal space 32A. The controller 130 controls the operation of the image recording apparatus 100.

A partition wall 41 is provided in the internal space 32A. The partition wall 41 partitions the rear lower part of the internal space 32A to define a seat storage space 32C. The seat storage space 32C is surrounded by the partition wall 41 and the lower housing 32.

The roll body 37 is accommodated in the sheet accommodation space 32C. The roll body 37 has a core tube and a long sheet S. The sheet S is wound around the core tube in a roll shape in the circumferential direction of the axis of the core tube.

As shown in FIG. 2, a holder 35 extending along the left-right direction 9 is located in the seat storage space 32C. When mounted, the holder 35 supports the roll body 37 such that the axis of the core tube of the roll body 37 is along the left-right direction 9 and the roll body 37 is rotatable in the circumferential direction of the axis. The holder 35 rotates as a driving force is transmitted from the transport motor 53 (see FIG. 10). As the holder 35 rotates, the roll body 37 supported by the holder 35 also rotates.

As shown in FIG. 2, the seat storage space 32C opens upward at the rear. A gap 42 is formed between the partition wall 41 and the rear surface 32B, that is, above the rear end of the roll body 37. The sheet S is pulled upward from the rear end of the roll body 37 and guided to the tensioner 45 through the gap 42 as the transport roller pair 36 and 40 rotate.

Tensioner 45 is located above partition wall 41 at the rear of internal space 32A. The tensioner 45 has an outer peripheral surface 45A facing outside of the lower housing 32. The upper end of the outer circumferential surface 45A is located at approximately the same vertical position as the nip D of the conveyance roller pair 36 in the vertical direction 7.

The sheet S pulled out from the roll body 37 is hung and abutted on the outer circumferential surface 45A. The sheet S is curved forward along the outer peripheral surface 45A, extends in the transport direction 8A, and is guided by the transport roller pair 36. The conveyance direction 8A is forward along the front-rear direction 8.

A conveying roller pair 36 is located in front of the tensioner 45. The transport roller pair 36 includes a transport roller 36A and a pinch roller 36B. The conveyance roller 36A and the pinch roller 36B abut each other at approximately the same vertical position as the upper end of the outer peripheral surface 45A to form a nip D.

A transport roller pair 40 is located in front of the transport roller pair 36 . The conveyance roller pair 40 includes a conveyance roller 40A and a pinch roller 40B. The conveyance roller 40A and the pinch roller 40B abut each other at approximately the same vertical position as the upper end of the outer circumferential surface 45A to form a nip.

The conveyance rollers 36A and 40A are rotated by receiving driving force from the conveyance motor 53 (see FIG. 10). The conveying roller pair 36 rotates while nipping the sheet S extending from the tensioner 45 in the conveying direction 8A, thereby sending it out in the conveying direction 8A along a conveying surface 43A of a conveying path 43, which will be described later. The transport roller pair 40 rotates while nipping the sheet S sent out from the transport roller pair 36, thereby sending it out in the transport direction 8A. Further, due to the rotation of the pair of conveyance rollers 36 and 40, the sheet S is pulled out from the sheet storage space 32C through the gap 42 toward the tensioner 45.

As shown in FIG. 2, a conveyance path 43 extending from the upper end of the outer circumferential surface 45A to the discharge port 33 is formed in the internal space 32A. The conveyance path 43 extends substantially linearly along the conveyance direction 8A, and is a space through which the sheet S can pass. Specifically, the conveyance path 43 extends along a conveyance surface 43A that extends in the conveyance direction 8A and the left-right direction 9 and is long in the conveyance direction 8A. In addition, in FIG. 2, the conveyance surface 43A is shown by a two-dot chain line indicating the conveyance path 43. The conveyance path 43 is divided by guide members (not shown) located apart in the vertical direction 7, the head 38, the conveyance belt 101, the support section 46, the heater 39, and the like. That is, the head 38, the conveyance belt 101, the support section 46, and the heater 39 are located along the conveyance path 43.

The head 38 is located above the conveyance path 43 and on the downstream side of the conveyance roller pair 36 in the conveyance direction 8A. The head 38 has a plurality of nozzles 38A that open at a nozzle surface 50 (see FIG. 4). Ink (an example of liquid) is ejected downward from the plurality of nozzles 38A toward the sheet S supported by the conveyor belt 101. As a result, an image is recorded on the sheet S. The configuration of head 38 will be explained later.

The first support mechanism 51 is located below the conveyance path 43 and downstream of the conveyance roller pair 36 in the conveyance direction 8A. The first support mechanism 51 is located below the head 38 and faces the head 38 . The first support mechanism 51 includes a conveyor belt 101 and a support member 104. The conveyance belt 101 supports the sheet S that is conveyed in the conveyance direction 8A by the conveyance roller pair 36 and positioned directly below the head 38. The conveyance belt 101 conveys the supported sheet S in the conveyance direction 8A. The support member 104 can support the maintenance mechanism 60.

The first support mechanism 51 includes a conveyor belt 101, a drive roller 102, a driven roller 103, a support member 104, a gear 105, and a gear 106. Note that in each figure, illustration of the teeth of the gears 105 and 106 is omitted.

The drive roller 102 and the driven roller 103 are rotatably supported by a support member 104. The drive roller 102 and the driven roller 103 are spaced apart from each other in the front-rear direction 8 (conveyance direction 8A). The conveyor belt 101 is an endless belt. The conveyor belt 101 is stretched around a driving roller 102 and a driven roller 103 . The conveyance belt 101 is arranged within the conveyance path 43 in the left-right direction 9 .

The drive roller 102 is rotated by the driving force provided by the conveyance motor 53 (see FIG. 10), and rotates the conveyance belt 101. As the conveyor belt 101 rotates, the driven roller 103 rotates. The conveyor belt 101 has a conveyor surface 108. The conveying surface 108 is an upper portion of the outer circumferential surface of the conveying belt 101, and extends along the conveying direction 8A. The conveyance surface 108 faces the nozzle 38A of the head 38 with the conveyance path 43 in between. The conveying surface 108 supports the sheet S conveyed between the pair of conveying rollers 36 and 40 from below, and applies a conveying force to the sheet S. Thereby, the conveyance belt 101 conveys the sheet S located on the conveyance path 43 in the conveyance direction 8A along the conveyance surface 108.

The support member 104 includes a shaft 109A. The shaft 109A is rotatably supported by the lower housing 32. The shaft 109A extends in the left-right direction 9 (a direction perpendicular to the transport direction 8A and parallel to the nozzle surface 50 of the discharge module 49). The shaft 109A is provided upstream of the drive roller 102 in the conveying direction 8A. The shaft 109A is located below the conveyance roller pair 36.

The shaft 109A rotates as driving force is transmitted from the shaft motor 59 (see FIG. 10). By rotating the shaft 109A, the support member 104 rotates around the shaft 109A. The rotating tip 51A of the first support mechanism 51 is located downstream of the shaft 109A in the transport direction 8A.

The support member 104 has a first attitude parallel to the nozzle surface 50 of the discharge module 49 (see FIG. 2), and a second attitude in which it is tilted about the axis 109A from the first attitude and the rotating tip 51A is located below the axis 109. The posture can be changed into two postures (see FIG. 13).

As shown in FIG. 2, when the first support mechanism 51 is in the first attitude, the conveying surface 108 of the conveying belt 101 extends along the front-rear direction 8. Thereby, the conveyor belt 101 can convey the sheet S located on the conveyance path 43 forward and send it to the support section 46 .

As shown in FIG. 13, when the first support mechanism 51 is in the second attitude, the conveying surface 108 of the conveying belt 101 extends along the inclined direction 6 which goes downward as it goes forward. Note that the inclination direction 6 is a direction that is perpendicular to the left-right direction 9 and intersects with the conveyance direction 8A.

As shown in FIG. 2, the gears 105 and 106 are rotatably supported by the support member 104 of the first support mechanism 51. As shown in FIG. The gear 106 is connected to the first motor 55 (see FIG. 10) directly or via another gear, and is provided with driving force from the first motor 55.

The heater 39 is located below the conveyance path 43, downstream of the head 38 in the conveyance direction 8A, and upstream of the conveyance roller pair 40 in the conveyance direction 8A. The heater 39 is supported by the frame in front of the first support mechanism 51 and extends in the left-right direction 9. The heater 39 includes a heat transfer plate (not shown) and a film heater (not shown). The heat transfer plate is made of metal and has a support surface that extends in the front, rear, left, and right directions at approximately the same vertical position as the conveyance surface 108 of the conveyance belt 101 . The sheet S sent out from the first support mechanism 51 is conveyed forward on the support surface of the heat transfer plate. The film heater is fixed to the lower surface of the heat transfer plate and generates heat under the control of the controller 130. This heat is transferred to the sheet S on the heat transfer plate via the heat transfer plate. Further, heat from the heater 39 is recovered by a duct 145 arranged above the heater 39.

The duct 145 is disposed above the conveyance path 43, downstream of the head 38 in the conveyance direction 8A, and upstream of the conveyance roller pair 40.

The support portion 46 is located below the conveyance path 43. The support portion 46 is located downstream of the head 38 and the first support mechanism 51 in the transport direction 8A. A heater 39 is located at the rear of the support portion 46. The front portion of the support portion 46 faces the conveyance roller 40A. The support portion 46 is located upstream of the cutter unit 26 in the transport direction 8A.

The support portion 46 is supported by the lower housing 32 so as to be rotatable around a shaft (not shown) extending in the left-right direction 9 . As shown in FIG. 3, when the upper housing 31 is in the open position, the support part 46 is rotatable between a laid down position shown by a solid line in FIG. 3 and an upright position shown by a broken line in FIG. .

When the support portion 46 is in the collapsed position, the rotation tip 46B of the support portion 46 is located forward of the rotation base end 46A (downstream in the transport direction 8A). When the support portion 46 is in the laid down position, the support portion 46 constitutes a part of the conveyance path 43 and is capable of supporting the sheet S conveyed in the conveyance direction 8A by the conveyance belt 101. When the support part 46 is in the upright position, the rotating tip 46B of the support part 46 is located higher than when the support part 46 is in the collapsed position, and the maintenance mechanism 60 can be exposed to the outside. The shaft of the support part 46 is provided at the rear end of the support part 46 and extends in the left-right direction 9.

The second support mechanism 52 is supported by the lower housing 32 so as to be movable in an orthogonal direction 10 orthogonal to the inclination direction 6 and the left-right direction 9 . The second support mechanism 52 can support the maintenance mechanism 60. The second support mechanism 52 is disposed to extend in the inclination direction 6 as a whole, and is movable toward and away from the wiper cleaning mechanism 80 by a ball screw (not shown). The second support mechanism 52 supports the maintenance mechanism 60 and supports the movement of the maintenance mechanism 60 in a slidable manner.

The gears 118, 119, and 120 are rotatably supported by the main body 115 of the second support mechanism 52. Gear 120 meshes with gears 118 and 119. When gear 120 rotates, gears 118 and 119 rotate in the same direction. The gear 120 is connected to the second motor 56 (see FIG. 10) directly or via another gear, and is provided with driving force from the second motor 56. The gears 118 and 119 can mesh with the rack 154 of the maintenance mechanism 60 located at opposing positions.

The CIS 25 is located above the transport path 43 and downstream of the transport roller pair 40 in the transport direction 8A. The CIS 25 can read the image on the printed surface of the sheet.

The cutter unit 26 is located above the conveyance path 43 and downstream of the CIS 25 in the conveyance direction 8A. The cutter unit 26 has a cutter 28 mounted on a cutter carriage 27. By moving the cutter 28, the sheet S located on the conveyance path 43 is cut along the left-right direction 9.

The mounting case 110 is located near the front end and lower end of the lower housing 32, and has a box shape that opens toward the front. The ink tank 34 is inserted backward into the mounting case 110. An ink needle 112 extending forward is located on the rearward end surface 111 of the mounting case 110. The front end of the ink needle 112 is open, and the rear end is connected to an ink circuit 113. The ink circuit 113 connects the internal space of the ink needle 112 and the head 38 so that ink can flow therebetween. When the ink tank 34 is installed in the installation case 110, the ink needle 112 is inserted into the outlet of the ink tank 34. As a result, the ink stored in the ink tank 34 is supplied to the head 38 through the ink needle 112 and the ink circuit 113. The configuration of the ink circuit 113 will be explained later. A contact point 114 is located on the end surface 111 . The contact 114 is electrically connected to the IC board 70 included in the ink tank 34 when the ink tank 34 is mounted on the mounting case 110. The controller 130 can access the storage area of the IC board 70 through the contacts 114.

The ink tank 34 stores ink. Ink is a liquid containing pigments and the like. The internal space of the ink tank 34 is a storage chamber that stores ink. The storage chamber may be in communication with the outside and the atmosphere, or may be in the form of a bag that can be contracted as the ink flows out, such as a pouch. Ink is supplied from an ink tank 34 mounted in a mounting case 110 to a head 38 through an ink circuit 113. An IC board 70 is located on the rear surface of the ink tank 34. The IC board 70 stores identification information indicating that it is an ink tank 34 in a storage area.

The storage liquid tank 11 shown in FIG. 9 has the same configuration as the ink tank 34 except that the stored liquid is a storage liquid. The storage liquid tank 11 can also be attached to the attachment case 110. Preservation liquid is supplied to the head 38 from a storage liquid tank 11 attached to a mounting case 110 through an ink circuit 113. An IC board 12 is located on the rear surface of the storage liquid tank 11 . The IC board 12 stores identification information indicating that it is the storage liquid tank 11 in a storage area.

As shown in FIG. 2, the cleaning liquid tank 76 stores cleaning liquid. The cleaning liquid is for cleaning the nozzle 38A of the head 38. The cleaning liquid tank 76 is located below the second support mechanism 52, which will be described later. The internal space of the cleaning liquid tank 76 is a storage chamber that stores the cleaning liquid. The cleaning liquid tank 76 includes a cleaning liquid main tank 76A and a cleaning liquid sub-tank 76B.

As shown in FIG. 9, the cleaning liquid main tank 76A is housed in a waste liquid tank 77. The cleaning liquid main tank 76A is in the form of a bag, such as a pouch, that can be contracted as the cleaning liquid flows out. The cleaning liquid main tank 76A is connected to a cleaning liquid supply channel 304 that is connected to the cleaning liquid sub-tank 76B. A cleaning fluid replenishment valve 305 that can open and close the cleaning fluid replenishment channel 304 is arranged in the cleaning fluid replenishment channel 304 . The opening and closing of the cleaning liquid replenishment valve 305 is controlled by the controller 130.

The cleaning liquid sub-tank 76B is arranged outside the waste liquid tank 77. The cleaning liquid sub-tank 76B is connected to the cleaning liquid main tank 76A through a cleaning liquid supply channel 304. A first liquid level sensor 303 is provided in the cleaning liquid sub-tank 76B. The first liquid level sensor 303 detects the presence or absence of cleaning liquid at a predetermined height in the internal space of the cleaning liquid sub-tank 76B. The first liquid level sensor 303 outputs a detection signal to the controller 130. The first liquid level sensor 303 outputs an ON signal as a detection signal when it detects cleaning liquid, and outputs an OFF signal as a detection signal when it does not detect cleaning liquid. Based on the detection signal output by the first liquid level sensor 303, the controller 130 determines whether the liquid level has reached a predetermined height in the internal space of the cleaning liquid sub-tank 76B.

A connection channel 301 (an example of a third channel) connected to the ink sub-tank 181 is connected to the cleaning liquid sub-tank 76B. One end 301A of the connection channel 301 opens to the upper wall 76BB of the cleaning liquid sub-tank 76B. The other end 301B of the connection channel 301 opens to the upper wall 181A of the ink subtank 181. A tank connection valve 302 that can open and close the connection flow path 301 is arranged in the connection flow path 301 . Opening and closing of tank connection valve 302 is controlled by controller 130. An ink sub-tank 181 is connected to the connection channel 301 . Further, a negative pressure pump 193 is connected to the connection channel 301. The negative pressure pump 193 makes the internal spaces of the ink sub-tank 181 and the cleaning liquid sub-tank 76B negative pressure by discharging the air in the connection channel 301 to the outside. Driving of the negative pressure pump 193 is controlled by the controller 130.

The waste liquid tank 77 is a container into which the cleaning liquid is discharged, and is communicated with the outside and the atmosphere. A third liquid level sensor 308 is provided in the waste liquid tank 77. The third liquid level sensor 308 is an optical sensor. The third liquid level sensor 308 detects the presence or absence of waste liquid at a predetermined height in the internal space of the waste liquid tank 77. The third liquid level sensor 308 outputs a detection signal to the controller 130. The third liquid level sensor 308 outputs an ON signal as a detection signal when cleaning liquid is detected, and outputs an OFF signal as a detection signal when cleaning liquid is not detected. The controller 130 determines whether the liquid level has reached a predetermined height in the internal space of the waste liquid tank 77 based on the detection signal output by the third liquid level sensor 308. Note that the third liquid level sensor 308 is not particularly limited as long as it can detect the presence or absence of waste liquid at a predetermined height. For example, the third liquid level sensor may be a transmission type optical sensor or a reflection type optical sensor. Further, the cleaning liquid tank 76 and the waste liquid tank 77 may also be removable from the image recording apparatus 100, similarly to the ink tank 34.

The maintenance mechanism 60 is for maintaining the head 38. The maintenance mechanism 60 is configured to be movable, and is moved directly below the head 38 when maintenance of the head 38 is performed (see FIG. 11).

Maintenance of the head 38 includes purge processing, cap cleaning processing, wiping processing, empty suction processing, and cleaning liquid replenishment processing. As shown in FIG. 11, the purge process is a process in which the nozzle surface 50 is covered with a cap 62, which will be described later, of the maintenance mechanism 60, and ink is sucked from the nozzle 38A by the suction pump 74. The cap cleaning process is a process in which the nozzle surface 50 of the head 38 is cleaned with a cleaning liquid sent into the internal spaces 67A, 67B, and 67C of the cap 62 while the nozzle surface 50 is covered with the cap 62. The wiping process, as shown in FIG. 12, is a process in which the nozzle surface 50 of the head 38 is wiped by a sponge wiper 64 (an example of a wiper), which will be described later, of the maintenance mechanism 60. The empty suction process is a process for returning the cleaning liquid in the return tube 176 to the cleaning liquid sub-tank 76B. The cleaning liquid replenishment process is a process of replenishing the cleaning liquid from the cleaning liquid main tank 76A to the cleaning liquid sub-tank 76B. The configuration of the maintenance mechanism 60 will be explained later.

The wiper cleaning mechanism 80 is for cleaning the cap 62 and rubber wiper 63 of the maintenance mechanism 60. The maintenance mechanism 60 is moved directly below the wiper cleaning mechanism 80 when the cap 62 and rubber wiper 63 are cleaned. The surface of the wiper cleaning mechanism 80 facing the maintenance mechanism 60 is formed of a sponge and holds a maintenance liquid. The wiper cleaning mechanism 80 can come into contact with the lip 66 and the rubber wiper 63 located in the retracted position. Thereby, the wiper cleaning mechanism 80 wipes the ink adhering to the lip 66 of the cap 62 and the rubber wiper 63.

[Head 38]
As shown in FIGS. 2 and 4, the head 38 has a generally rectangular parallelepiped shape that is long in the left-right direction 9. As shown in FIGS. The head 38 includes a frame 48 and three ejection modules 49A, 49B, and 49C. Hereinafter, the three discharge modules 49A, 49B, and 49C are also collectively referred to as the discharge module 49. Note that the number of discharge modules 49 is not limited to three, and may be one, for example.

As shown in FIGS. 2 and 4, the discharge module 49 is supported by a frame 48. As shown in FIGS. The lower surface of the discharge module 49 is exposed downward. The discharge module 49 is arranged within the conveyance path 43 in the left-right direction 9 .

As shown in FIG. 4(A), the discharge modules 49A and 49B are arranged at the same position in the transport direction 8A. The discharge modules 49A and 49B are arranged at intervals in the left-right direction 9. The discharge module 49C is arranged downstream of the discharge modules 49A and 49B in the transport direction 8A. The discharge module 49C is arranged between two discharge modules 49A and 49B adjacent to each other in the left-right direction 9. The left end of the discharge module 49C is located to the left of the right end of the discharge module 49A. The right end of the discharge module 49C is located to the right of the left end of the discharge module 49B. That is, in the left-right direction 9, the end of the discharge module 49C and the ends of the discharge modules 49A and 49B overlap.

Each discharge module 49A, 49B, 49C includes a plurality of nozzles 38A. Each nozzle 38A is opened to a nozzle surface 50 of each discharge module 49A, 49B, 49C. The nozzle surface 50 is a surface that extends in the front-rear direction 8 and the left-right direction 9. As described above, ink is ejected downward from the plurality of nozzles 38A toward the sheet S supported by the conveyor belt 101 of the first support mechanism 51, and an image is recorded on the sheet S.

As shown in FIG. 4(B), the ejection module 49 has an inflow port 22 and an outflow port 23 connected to the ink circuit 113. The inflow port 22 and the outflow port 23 are each connected to a manifold 24. Manifold 24 is connected to a plurality of nozzles 38A. The ink that has flowed into the manifold 24 through the inflow port 22 is ejected to the outside through the nozzles 38A by driving piezo elements (not shown) located corresponding to each nozzle 38A. Ink within manifold 24 can be circulated through inlet port 22 and outlet port 23.

The head 38 is arranged along the vertical direction 7 at a recording position shown in FIGS. 13 and 14, a capping position shown in FIG. 11, a wiping position shown in a solid line in FIG. Move to cap position. The recording position is the position of the head 38 when recording an image on the sheet S supported by the conveyor belt 101. The capped position is the position of the head 38 when the discharge module 49 is covered by the cap 62 of the maintenance mechanism 60. The capped position is a position above the recording position (a position farther from the first support mechanism 51 than the recording position). The wiped position is the position of the head 38 when the sponge wiper 64 of the maintenance mechanism 60 wipes the nozzle surface 50 of the discharge module 49. The wiped position is a position above the capped position. The uncapped position is the position of the head 38 when the head 38 is completely separated from the maintenance mechanism 60. The uncapped position is a position above the wiped position.

As shown in FIG. 2, the head 38 is moved by a ball screw 29. The ball screw 29 includes a screw shaft 29A and a nut member 29B. The screw shaft 29A is rotatably supported by the lower housing 32 around an axis along the vertical direction 7. The screw shaft 29A rotates by receiving driving force from the head motor 54 (see FIG. 10). The nut member 29B moves upward when the screw shaft 29A rotates in the normal direction, and moves downward when the screw shaft 29A rotates in the reverse direction. Note that the configuration for vertically moving the head 38 is not limited to the configuration using the ball screw 29, and various known configurations can be adopted.

[Maintenance mechanism 60]
As shown in FIG. 5, the maintenance mechanism 60 includes a support base 61, a sponge wiper 64, a rubber wiper 63, and a cap 62. In the following description of the maintenance mechanism 60, it is assumed that the maintenance mechanism 60 is supported by the first support mechanism 51 and the second support mechanism 52 in the second posture.

The support stand 61 includes a bottom stand 61A, a main body 61B placed on the bottom stand 61A, and a wiper holder 61C that holds the sponge wiper 64 and the rubber wiper 63 on the main body 61B. The bottom pedestal 61A has a box shape with an open top. The bottom stand 61A includes a first bottom plate 121, a first edge plate 122 erected upward from the periphery of the first bottom plate 121, an extending piece 125, and a rack 154 (see FIG. 2). .

The first bottom plate 121 has a flat plate shape that extends in the inclination direction 6 and the left-right direction 9 . The upper and lower surfaces of the first bottom plate 121 are formed into a rectangular shape that is longer in the left-right direction 9 than in the inclination direction 6 . The lower surface of the first bottom plate 121 can come into contact with the upper surface of the first support mechanism 51 from above. Thereby, the maintenance mechanism 60 can be supported by the first support mechanism 51. The lower surface of the first bottom plate 121 can come into contact with the upper surface of the second support mechanism 52 from above. Thereby, the maintenance mechanism 60 can be supported by the second support mechanism 52.

The first edge plate 122 has a rectangular frame shape in plan view. The extending piece 125 extends rightward from the lower end of the right wall of the first edge plate 122. The extending piece 125 extends from one end of the right wall of the first edge plate 122 in the inclination direction 6 to the other end.

As shown in FIG. 6, the rack 154 is formed on the lower surface of the extension piece 125. The rack 154 extends from one end of the extending piece 125 in the inclination direction 6 to near the other end. The rack 154 can vertically face the upper surface of the first support mechanism 51.

The rack 154 can mesh with the gear 105 of the first support mechanism 51. The maintenance mechanism 60 slides along the upper surface of the first support mechanism 51 by rotating the gear 105 while the rack 154 and the gear 105 are in mesh with each other.

The rack 154 can mesh with the gears 118 and 119 of the second support mechanism 52. The maintenance mechanism 60 slides along the upper surface of the second support mechanism 52 by rotating the gear 120 with the rack 154 and at least one of the gears 118 and 119 meshing with each other.

As a result, the maintenance mechanism 60 can be moved to a standby position shown in FIG. 2, a retreat position shown in broken lines in FIG. 12, a maintenance position shown in FIG. 11, and a wiping position shown in FIG. 12, as described later. It is. The maintenance mechanism 60 at the maintenance position and the wiping position faces the nozzle surface 50 of the ejection module 49 of the head 38 in the vertical direction 7 . The maintenance mechanism 60 in the standby position and the retreat position is in a state separated from the nozzle surface 50.

As shown in FIG. 5, the main body 61B has a substantially box-like shape with an open upper part. The main body 61B is fixed to the bottom stand 61A. The main body 61B includes a second bottom plate 151, a second edge plate 152 erected upward from the second bottom plate 151, and a liquid flow path 153 (see FIG. 7) that circulates the cleaning liquid stored in the cleaning liquid tank 76. It is equipped with

As shown in FIGS. 5 and 7, the second bottom plate 151 has a flat plate shape that extends in the inclination direction 6 and the left-right direction 9. As shown in FIGS. The upper and lower surfaces of the second bottom plate 151 are formed in a rectangular shape that is longer in the left-right direction than in the inclination direction 6. The second edge plate 152 has a rectangular frame shape in plan view.

As shown in FIG. 7, the liquid flow path 153 is formed on the upper surface of the second bottom plate 151. The liquid flow path 153 is a groove recessed downward from the upper surface of the second bottom plate 151, and is open upward. In plan view, the liquid flow path 153 has a continuous U-shape that extends in the left-right direction 9 and is folded back in a U-turn. The liquid flow path 153 extends so as to connect in series the sponge wiper 64A, the sponge wiper 64B, and the sponge wiper 64C arranged on the groove. The liquid flow path 153 has a first flow path 153A, an intermediate flow path 153B, and a second flow path 153C.

The first flow path 153A is located on the upstream side of the liquid flow path 153 in the direction of flow of the cleaning liquid. The first flow path 153A is a portion extending in the left-right direction 9 on the front side of the main body 61B.

The intermediate flow path 153B is located downstream of the first flow path 153A in the cleaning liquid flow direction. The intermediate flow path 153B extends in the forward inclination direction 5 from the downstream end of the first flow path 153A to the intermediate portion of the main body 61b in the inclination direction 6.

The second flow path 153C is located on the downstream side of the liquid flow path 153 in the direction of flow of the cleaning liquid. The second flow path 153C extends to the right from the downstream end of the intermediate flow path 153B.

As shown in FIGS. 7 and 9, an inlet 171 through which the cleaning liquid flows into the first flow path 153A is opened in the inner wall surface of the groove at the upstream end of the first flow path 153A. One end of a first supply tube 175 is connected to the inlet 171 . The other end of the first supply tube 175 reaches the outside of the first support mechanism 51, is connected to the cleaning liquid sub-tank 76B, and opens at a position lower than the water level of the cleaning liquid stored in the cleaning liquid sub-tank 76B. The first supply tube 175 is provided with a supply pump 306 . The supply pump 306 supplies the cleaning liquid from the cleaning liquid sub-tank 76B to the first flow path 153A through the first supply tube 175. Driving of supply pump 306 is controlled by controller 130. A wiper cleaning valve 311 that can open and close the flow path of the first supply tube 175 is arranged between the supply pump 306 and the cleaning liquid sub-tank 76B in the first supply tube 175. The opening and closing of the wiper cleaning valve 311 is controlled by the controller 130.

An outflow port 174 through which the cleaning liquid flows out is opened on the inner wall surface at the downstream end of the second flow path 153C. One end of a return tube 176 is connected to the outlet 174 . The other end of the return tube 176 reaches the outside of the first support mechanism 51, is connected to the cleaning liquid sub-tank 76B, and opens at a position higher than the water level of the cleaning liquid stored in the cleaning liquid sub-tank 76B. The return tube 176 is provided with a return pump 75 (an example of a wiper pump). The return pump 75 returns the cleaning liquid from the second flow path 153C to the cleaning liquid sub-tank 76B through the return tube 176. Driving of the return pump 75 is controlled by the controller 130. The first supply tube 175, return tube 176, and liquid flow path 153 are examples of wiper flow paths.

As shown in FIG. 5, the wiper holder 61C includes a sponge wiper 64 and a rubber wiper 63. The sponge wiper 64 and the rubber wiper 63 are supported by the main body 61B by a wiper holder 61C.

[Sponge wiper 64]
The sponge wiper 64 is made of sponge. In this embodiment, three sponge wipers 64 (64A, 64B, 64C) are provided. Hereinafter, the three sponge wipers 64A, 64B, and 64C are also collectively referred to as the sponge wiper 64. The sponge wiper 64 is formed in a rectangular parallelepiped shape in which the length in the left-right direction 9 is longer than the length in the inclination direction 6 and the up-down direction 7 . The length of the sponge wiper 64 in the vertical direction 7 is longer than the length in the inclined direction 6.

The sponge wiper 64A and the sponge wiper 64B are arranged in the first flow path 153A of the liquid flow path 153. The sponge wiper 64A is arranged upstream of the sponge wiper 64B. The sponge wiper 64C is arranged in the second flow path 153C of the liquid flow path 153.

The sponge wiper 64A, the sponge wiper 64B, and the sponge wiper 64C correspond to the discharge module 49A, the discharge module 49B, and the discharge module 49C in the vertical direction 7, respectively. The sponge wiper 64A and the sponge wiper 64B are spaced apart from each other in the left-right direction 9. The sponge wiper 64C is spaced apart from the sponge wiper 64A and the sponge wiper 64B in the forward inclination direction 5. The sponge wiper 64C is located midway between the sponge wiper 64A and the sponge wiper 64B in the left-right direction 9.

The sponge wiper 64A corresponds to the discharge module 49A and can face the discharge module 49A in the vertical direction 7. As shown in FIGS. 5 and 7, the sponge wiper 64A is disposed on the right side of the center of the first flow path 153A in the left-right direction 9.

[Rubber wiper 63]
The rubber wiper 63 is made of rubber. In this embodiment, three rubber wipers 63 (63A, 63B, 63C) are provided. Hereinafter, the three rubber wipers 63A, 63B, and 63C are also collectively referred to as the rubber wiper 63.

The rubber wiper 63 is formed into a flat plate shape that extends in the vertical direction 7 and the horizontal direction 9. The length of the rubber wiper 63 in the inclined direction 6 is shorter than the length of the sponge wiper 64 in the inclined direction 6. Thereby, the rubber wiper 63 is easily bent when it comes into contact with the nozzle surface 50 of the discharge module 49 during the wiping process. The length of the rubber wiper 63 in the left-right direction 9 is slightly longer than the length of the sponge wiper 64 in the left-right direction 9. The length of the rubber wiper 63 from the support base 61 is longer than the length of the sponge wiper 64 from the support base 61. The rubber wiper 63 is located outside both ends of the sponge wiper 64 in the left-right direction 9 in the left-right direction 9 . The upper end of the rubber wiper 63 is tapered. This allows the upper end of the rubber wiper 63 to easily come into contact with the nozzle surface 50 of the discharge module 49 during the wiping process.

The rubber wiper 63A and the rubber wiper 63B are arranged outside the liquid flow path 153. The rubber wiper 63A, the rubber wiper 63B, and the rubber wiper 63C correspond to the discharge module 49A, the discharge module 49B, and the discharge module 49C in the vertical direction 7, respectively. The rubber wiper 63A, the rubber wiper 63B, and the rubber wiper 63C are arranged on the support base 61 at intervals in the backward inclined direction 4 from the sponge wiper 64A, the sponge wiper 64B, and the sponge wiper 64C, respectively.

[Cap 62]
As shown in FIG. 5, the cap 62 is supported by a support base 61. A plurality of caps 62 are provided. In this embodiment, the cap 62 is composed of three caps 62A, 62B, and 62C. Hereinafter, the three caps 62A, 62B, and 62C will also be collectively referred to as caps 62.

The cap 62 is made of an elastic material such as rubber or silicone. The cap 62 has a box shape with an open top.

The cap 62A, the cap 62B, and the cap 62C can face the discharge module 49A, the discharge module 49B, and the discharge module 49C in the vertical direction 7, respectively. The cap 62A, the cap 62B, and the cap 62C are spaced from the sponge wiper 64A, the sponge wiper 64B, and the sponge wiper 64C, respectively, in the forward inclined direction 5. When the maintenance mechanism 60 is in the maintenance position, the caps 62A, 62B, and 62C have lips 66A, 66B, and 66C (see FIG. 8) that abut the nozzle surface 50 to seal the internal spaces 67A, 67B, and 67C, respectively. . The caps 62A, 62B, and 62C each have cap channels 68A, 68B, and 68C that communicate the interior spaces 67A, 67B, and 67C with the outside. The cap channels 68A, 68B, 68C are supply channels 20A, 20B, 20C through which the cleaning liquid flows into the internal spaces 67A, 67B, 67C of the cap 62, and supply channels 20A, 20B, 20C through which the cleaning liquid flows into the internal spaces 67A, 67B, 67C of the cap 62A, 62B, 62C. It has discharge channels 21A, 21B, and 21C flowing out from 67C.

Hereinafter, the three lips 66A, 66B, and 66C will also be collectively referred to as the lip 66. Similarly, the internal spaces 67A, 67B, 67C, the cap channels 68A, 68B, 68C, the supply channels 20A, 20B, 20C, and the discharge channels 21A, 21B, 21C, respectively. Also referred to as the passage 68, the supply passage 20, and the discharge passage 21.

As shown in FIG. 8, the cap 62A corresponds to the ejection module 49A and can face the ejection module 49A in the vertical direction 7. The cap 62A is spaced from the sponge wiper 64A in the forward inclined direction 5. The bottom plate 69 of the cap 62A is formed with a supply flow path 20A through which the cleaning liquid flows into the cap 62A and a discharge flow path 21A through which the cleaning liquid flows out from the cap 62A. One end of a second supply tube 177 is connected to the supply channel 20A of the cap 62A. The other end of the second supply tube 177 extends to the outside of the maintenance mechanism 60 and is connected to the cleaning liquid tank 76 (see FIG. 2). One end of a first waste liquid tube 178 is connected to the discharge channel 21A. The other end of the first waste liquid tube 178 extends outside the maintenance mechanism 60 and is connected to the waste liquid tank 77 (see FIG. 2).

The cap 62B corresponds to the discharge module 49B and can face the discharge module 49B in the vertical direction 7. The cap 62B is spaced from the sponge wiper 64B in the forward inclined direction 5. The bottom plate 69 of the cap 62B is formed with a supply passage 20B through which the cleaning liquid flows into the cap 62B and a discharge passage 21B through which the cleaning liquid flows out from the cap 62B. One end of a third supply tube 179 branched from the second supply tube 177 is connected to the supply flow path 20B. One end of a second waste liquid tube 180 is connected to the discharge channel 21B. The other end of the second waste liquid tube 180 joins the first waste liquid tube 178 outside the maintenance mechanism 60 .

The cap 62C corresponds to the discharge module 49C and can face the discharge module 49C in the vertical direction 7. The cap 62C is spaced from the sponge wiper 64C in the forward inclined direction 5. A supply channel 20C through which the cleaning liquid flows into the cap 62C and a discharge channel 21C through which the cleaning liquid flows out from the cap 62C are formed in the bottom plate 69 of the cap 62C. One end of a fourth supply tube 201 branched from the second supply tube 177 is connected to the supply flow path 20C. One end of the third waste liquid tube 202 is connected to the discharge channel 21C. The other end of the third waste liquid tube 202 joins the first waste liquid tube 178 outside the maintenance mechanism 60 .

A cap cleaning valve 72 (see FIG. 9) is provided upstream of the branch point of the third supply tube 179 and the fourth supply tube 201 in the second supply tube 177. Opening and closing of the cap cleaning valve 72 is controlled by a controller 130.

The second waste liquid tube 180 and the third waste liquid tube 202 in the first waste liquid tube 178 are each provided with a suction pump 74 (see FIG. 2) on the upstream side of the confluence point. The three suction pumps 74 are driven by one suction pump motor 58 (see FIG. 10).

The total Ta of the volume of the supply channel 20A, the volume of the discharge channel 21A, the volume upstream of the suction pump 74 in the first waste liquid tube 178, and the volume of the internal space of the cap 62A is the volume of the supply channel 20B, Total Tb of the volume of the discharge channel 21B, the volume upstream of the suction pump 74 in the second waste liquid tube 180, and the volume of the internal space of the cap 62B, the volume of the supply channel 20C, and the volume of the discharge channel 21C and is equivalent to the total Tc of the volume upstream of the suction pump 74 in the third waste liquid tube 202 and the volume of the internal space of the cap 62C (total Ta=total Tb=total Tc).

[Ink circuit 113]
As shown in FIG. 9, the mounting case 110 and the ejection module 49 are connected by an ink circuit 113. The ink circuit 113 includes an ink sub-tank 181 (an example of a tank), flow paths 182, 183, 184, an atmosphere flow path 185 (an example of an atmosphere communication path), a bypass flow path 186, a replenishment valve 187, a purge cutoff valve 188, and a bypass valve. 189, an atmospheric release valve 190, a positive pressure pump 191, and a second liquid level sensor 192. The flow path 183 is an example of the first flow path. The flow path 184 is an example of the second flow path.

The ink sub-tank 181 is located above the mounting case 110 in the internal space of the housing 30. The ink sub-tank 181 stores ink in an internal space. The internal space of the ink sub-tank 181 is communicated with the ink needle 112 of the mounting case 110 through a flow path 182. When the ink tank 34 is attached to the attachment case 110, ink stored in the ink tank 34 can flow into the ink sub-tank 181 through the flow path 182. Furthermore, when the storage liquid tank 11 is attached to the mounting case 110, the storage liquid stored in the storage liquid tank 11 can flow into the ink sub-tank 181 through the flow path 182. A replenishment valve 187 is located in the flow path 182 . Replenishment valve 187 is controlled by controller 130 to open and close flow path 182 .

The internal space of the ink sub-tank 181 and the inflow port 22 of the ejection module 49 are communicated through a flow path 183. Ink or storage liquid stored in the internal space of the ink sub-tank 181 can be supplied to the ejection module 49 through the flow path 183. A positive pressure pump 191 is located in the flow path 183 . The positive pressure pump 191 is operated by the controller 130 controlling the drive of the pump motor 138 (see FIG. 10).

The internal space of the ink sub-tank 181 and the outflow port 23 of the ejection module 49 are communicated through a flow path 184. Ink or storage liquid in the manifold 24 of the ejection module 49 can be discharged to the ink sub-tank 181 through the flow path 184. A purge shutoff valve 188 is located in the flow path 184 . Purge shutoff valve 188 is controlled by controller 130 to open and close flow path 184 .

A bypass flow path 186 connects between the positive pressure pump 191 and the inflow port 22 in the flow path 183 and between the purge cutoff valve 188 and the ink sub-tank 181 in the flow path 184 . A bypass valve 189 is located in the bypass flow path 186 . Bypass valve 189 is controlled by controller 130 to open and close bypass channel 186.

The internal space of the ink sub-tank 181 and the outside communicate with each other through an atmospheric flow path 185. An atmosphere release valve 190 is located in the atmosphere flow path 185. The atmosphere release valve 190 is controlled by the controller 130 to open and close the atmosphere flow path 185.

A second liquid level sensor 192 is located in the ink sub-tank 181. The second liquid level sensor 192 detects the presence or absence of ink at a predetermined height in the internal space of the ink sub-tank 181. The second liquid level sensor 192 outputs a detection signal to the controller 130. The second liquid level sensor 192 outputs an ON signal as a detection signal when it detects ink, and outputs an OFF signal as a detection signal when it does not detect ink. The controller 130 determines whether the liquid level has reached a predetermined height in the internal space of the ink sub-tank 181 based on the detection signal output by the second liquid level sensor 192.

[Controller 130]
As shown in FIG. 10, the controller 130 includes a CPU 131, a ROM 132, a RAM 133, an EEPROM 134, and an ASIC 135, which are connected by an internal bus 137. The ROM 132 stores programs for controlling various operations of the CPU 131. The RAM 133 is used as a storage area for temporarily recording data, signals, etc. used when the CPU 131 executes the above program, or as a work area for data processing. The EEPROM 134 stores settings, flags, etc. that should be retained even after the power is turned off.

The ASIC 135 includes a transport motor 53, a head motor 54, a first motor 55, a second motor 56, a return pump motor 47, a supply pump motor 307, a suction pump motor 58, pump motors 138 and 139, a shaft motor 59, and a vertical drive. A motor 163 is connected. Also connected to the ASIC 135 are a cap cleaning valve 72, a replenishment valve 187, a purge cutoff valve 188, a bypass valve 189, an atmosphere release valve 190, a cleaning liquid replenishment valve 305, a tank connection valve 302, and a wiper cleaning valve 311. Note that each valve is connected to the ASIC 135 via a drive circuit for driving the valve.

The ASIC 135 generates a drive signal for rotating each motor, and controls each motor based on this drive signal. Each motor rotates forward or reverse in response to a drive signal from the ASIC 135. The controller 130 controls the drive of the conveyance motor 53 to rotate the holder 35, the conveyance roller 36A, the conveyance roller 40A, and the drive roller 102. The controller 130 controls the drive of the head motor 54, rotates the screw shaft 29A, and moves the head 38 along the vertical direction 7. The controller 130 controls the drive of the shaft motor 59 to rotate the first support mechanism 51 . The controller 130 controls the driving of the first motor 55 to rotate the gear 106 of the first support mechanism 51. The controller 130 controls the drive of the vertical drive motor 163 to rotate the screw shaft 161 and move the second support mechanism 52 along the orthogonal direction 10 . The controller 130 controls the drive of the second motor 56 to rotate the gear 120 of the second support mechanism 52. The controller 130 controls the return pump motor 78 to drive the return pump 75. The controller 130 controls the supply pump motor 307 to drive the supply pump 306 . The controller 130 controls the suction pump motor 58 to drive the three suction pumps 74. The controller 130 controls the drive of the pump motor 138 to drive the positive pressure pump 191. The controller 130 controls the pump motor 139 to drive the negative pressure pump 193.

An operation panel 44, a display section 44A, contacts 114, a first liquid level sensor 303, a second liquid level sensor 192, a third liquid level sensor 308, and a piezoelectric element (not shown) are connected to the ASIC 35. The operation panel 44 outputs an operation signal to the controller 130 according to a user's operation. The operation panel 44 may have, for example, push buttons or a touch sensor superimposed on the display. The controller 130 reads identification information from the storage area of the IC board 70 of the ink tank 34 or the IC board 12 of the storage liquid tank 11 through the contact 114 . The controller 130 causes the display unit 44A to display that the ink tank 34 is attached to the attachment case 110 based on the identification information. The controller 130 causes the display unit 44A to display that the preservation liquid tank 11 is attached to the attachment case 110 based on the identification information. The controller 130 receives detection signals from the first liquid level sensor 303, the second liquid level sensor 192, and the third liquid level sensor 308. The controller 130 causes the display unit 44A to display a message indicating that the waste liquid tank 77 is to be replaced based on the detection signal from the third liquid level sensor 308. The piezoelectric element operates by being supplied with power by the controller 130 via a drive circuit (not shown). The controller 130 controls power supply to the piezoelectric element and causes ink droplets to be selectively ejected from the plurality of nozzles 38A.

The controller 130 can receive a timing signal output from the timer 502. A timer 502 measures the elapsed time of the idle suction process. The timer 502 outputs a clock signal to the ASIC 135 according to the elapsed time. Note that the controller 130 may have a built-in timer 502.

Hereinafter, the operation of the maintenance mechanism 60 will be explained together with the purge process, the cleaning process, the wiping process, the empty suction process, the cleaning liquid supply process, and the image recording process. In this embodiment, the cleaning liquid is supplied and discharged together with the above processing.

[Purge treatment and cleaning treatment]
The image recording apparatus 100 is in a standby state when image recording processing is not being executed. In the standby state, as shown in FIG. 11, the head 38 is located at the capped position, the first support mechanism 51 is located at the first attitude supporting the maintenance mechanism 60, and the maintenance mechanism 60 is located at a maintenance position. At this time, the cap 62 covers the nozzle surface 50.

In the standby state, the controller 130 executes the purge process at a predetermined timing or when receiving an external command. In the following, a process will be described when the controller 130 receives an instruction to execute a purge process from the outside while the image recording apparatus 100 is in a standby state.

In the purge process, the controller 130 drives the suction pump 74 with the purge cutoff valve 188 and the bypass valve 189 open, and the replenishment valve 187, the atmosphere release valve 190, and the cap cleaning valve 72 closed. As a result, the ink in the nozzle 38A is sucked and passes from the internal spaces 67A, 67B, 67C of the cap 62 through the discharge channels 21A, 21B, 21C to the first waste liquid tube 178, the second waste liquid tube 180, and the third waste liquid tube. The ink is discharged through the waste liquid tube 202 into the waste liquid tank 77 . At this time, since the cap cleaning valve 72 is closed, the cleaning liquid is supplied from the cleaning liquid tank 76 to the caps 62A, 62B, and 62C through the second supply tube 177, the third supply tube 179, and the fourth supply tube 201. There isn't.

The controller 130 executes the cleaning process at a predetermined timing or when receiving an external command. In the following, a process will be described in which the controller 130 executes the cleaning process after the purge process is performed when the image recording apparatus 100 is in a standby state.

In the cleaning process, the controller 130 opens the cap cleaning valve 72 and drives the suction pump 74 with the replenishment valve 187, purge cutoff valve 188, bypass valve 189, and atmosphere release valve 190 closed. Thereby, the cleaning liquid is supplied from the cleaning liquid tank 76 to the internal spaces of the caps 62A, 62B, and 62C through the second supply tube 177, the third supply tube 179, and the fourth supply tube 201. Since the purge shutoff valve 188 and the bypass valve 189 are closed, no ink is discharged from the nozzle 38A of the head 38 into the internal spaces of the caps 62A, 62B, and 62C.

Subsequently, the controller 130 moves the head 38 to the uncapped position, and then drives the suction pump 74 with the cap cleaning valve 72 closed. As a result, the cleaning liquid flows from the internal spaces 67A, 67B, and 67C of the cap 62 through the discharge passages 21A, 21B, and 21C to the first waste liquid tube 178, the second waste liquid tube 180, and the third waste liquid tube 202 to the waste liquid tank. It is discharged at 77. As a result, ink remaining in the internal spaces 67A, 67B, 67C of the cap 62, the discharge channels 21A, 21B, 21C, the first waste liquid tube 178, the second waste liquid tube 180, and the third waste liquid tube 202 is washed away with the cleaning liquid. .

Further, the image recording apparatus 100 is in a standby state when image recording processing is not being executed, but when the image recording apparatus 100 is in a standby state, the controller 130 opens the cap cleaning valve 72, and also opens the replenishment valve 187 and the purge cutoff valve 188. A cleaning liquid supply process is executed in which the suction pump 74 is driven with the bypass valve 189 and the atmosphere release valve 190 closed. By the cleaning liquid supply process, the cleaning liquid is supplied from the cleaning liquid tank 76 to the internal spaces of the caps 62A, 62B, and 62C through the second supply tube 177, the third supply tube 179, and the fourth supply tube 201. Since the purge shutoff valve 188 and the bypass valve 189 are closed, no ink is discharged from the nozzle 38A of the head 38 into the internal spaces of the caps 62A, 62B, and 62C.

[Wiping process]
The controller 130 executes the wiping process with the sponge wipers 64A, 64B, and 64C impregnated with the cleaning liquid. The wiping process will be explained below.

In the wiping process, the controller 130 drives the pump 75. Thereby, the cleaning liquid is supplied from the cleaning liquid tank 76 to the support base 61 through the first supply tube 175. The cleaning liquid supplied to the support base 61 flows into the first flow path 153A in the liquid flow path 153 through the inlet 171. The cleaning liquid that has flowed into the first flow path 153A flows through the intermediate flow path 153B and the second flow path 153C in order, and is discharged from the outlet 174. At this time, the sponge wipers 64A, 64B, and 64C are impregnated with the cleaning liquid, and the sponge wipers 64A, 64B, and 64C are in a state in which the cleaning liquid is sufficiently contained. The cleaning liquid supplied to the liquid flow path 153 is returned to the cleaning liquid tank 76.

The controller 130 moves the head 38 downward from the uncapped position shown by the broken line in FIG. 12 to the wiped position shown by the solid line.

The maintenance mechanism 60 in the maintenance position is supported by the first support mechanism 51, and at this time, the rack 154 is meshed with the gear 105. When the first motor 55 is driven in this state and the gear 106 rotates clockwise in FIG. 11, the gear 105 rotates counterclockwise in FIG. As a result, the maintenance mechanism 60 at the maintenance position moves forward (downstream in the transport direction 8A) along the front-rear direction 8 (transport direction 8A) and reaches the wiping position (see FIG. 12).

In the process of the maintenance mechanism 60 moving from the maintenance position to the wiping position, the tips (upper ends) of the sponge wiper 64 and the rubber wiper 63 slide against the nozzle surface 50 of the discharge module 49 while coming into contact with the nozzle surface 50 . Specifically, the sponge wipers 64A, 64B, 64C and the rubber wipers 63A, 63B, 63C slide while in contact with the nozzle surfaces 50 of the discharge modules 49A, 49B, 49C. As a result, the nozzle surfaces 50 of the respective discharge modules 49A, 49B, and 49C are wiped by the sponge wipers 64A, 64B, and 64C, and then by the rubber wipers 63A, 63B, and 63C. As a result, foreign matter adhering to the nozzle surface 50 and the nozzle 38A opened in the nozzle surface 50 is removed.

When the maintenance mechanism 60 is in the wiping position, when the first motor 55 is driven and the gear 106 rotates counterclockwise in FIG. 12, the gear 105 rotates clockwise in FIG. As a result, the maintenance mechanism 60 at the wiping position moves rearward (upstream in the transport direction 8A) and reaches the maintenance position (see FIG. 11).

The controller 130 drives the shaft motor 59 to change the posture of the first support mechanism 51 from the first posture to the second posture (see FIG. 13).

[Empty suction processing and cleaning liquid replenishment processing]
After the wiping process, an empty suction process is performed to return the cleaning liquid in the return tube 176 to the cleaning liquid sub-tank 76B. Note that the state in which the return pump 75 and the supply pump 306 are stopped is defined as an initial state. Further, the cleaning liquid replenishment valve 305 is in a closed state. The atmosphere release valve 190 is in an open state.

Check the sign of the step. As shown in FIG. 15, the controller 130 first drives the return pump 75 and the negative pressure pump 193 (S21). In this state, the controller 130 opens the tank connection valve 302 (S22). As a result, the idle suction process is started. As a result, due to the suction action of the return pump 75, the cleaning liquid in the return tube 176 is returned to the cleaning liquid sub-tank 76B, and the air in the cleaning liquid sub-tank 76B flows out into the connecting flow path 301 and is discharged to the outside. At this time, there is a risk that the cleaning liquid in the cleaning liquid sub-tank 76B will flow out into the connecting passage 301 and into the ink sub-tank 181 together with the air flowing out into the connecting passage 301. Since the ink is sucked and discharged to the outside, it is difficult to flow into the ink sub-tank 181.

The controller 130 causes the timer 502 to start measuring time, and in response to determining that a predetermined period of time (for example, 10 seconds) has not elapsed based on the clock signal from the timer 502 (S23: No), the predetermined period of time starts. Wait until the time elapses. In response to determining that the predetermined time has elapsed based on the clock signal from the timer 502 (S23: Yes), the controller 130 closes the tank connection valve 302 and opens the cleaning liquid replenishment valve 305 ( S24).

The controller 130 stops the return pump 75 and the negative pressure pump 193 (S25). As a result, there is a risk that the cleaning liquid in the cleaning liquid sub-tank 76B may flow out into the connecting flow path 301 due to the pressure that has slightly accumulated in the cleaning liquid sub-tank 76B. However, since the tank connection valve 302 is closed, the cleaning liquid is The ink does not flow into the ink sub-tank 181 through 301. Further, the pressure slightly accumulated in the cleaning liquid sub-tank 76B causes the cleaning liquid to be returned to the cleaning liquid main tank 76A, so that the pressure in the cleaning liquid sub-tank 76B is reduced.

In response to receiving the detection signal from the first liquid level sensor 303 (S26: Yes), the controller 130 ends the empty suction process. In response to not receiving the detection signal from the first liquid level sensor 303 (S26: No), the controller 130 closes the atmosphere release valve 190 and opens the tank connection valve 302 (S27). At this time, since the pressure inside the cleaning liquid sub-tank 76B is reduced in S25 and the atmosphere release valve 190 is closed, air flow from the cleaning liquid sub-tank 76B to the ink sub-tank 181 through the connection channel 301 is difficult to occur. . Therefore, the cleaning liquid is prevented from flowing into the ink sub-tank 181 from the cleaning liquid sub-tank 76B through the connection channel 301.

The controller 130 drives the negative pressure pump 193 (S28). Thereby, the cleaning liquid replenishment process is started. Specifically, the inside of the cleaning liquid sub-tank 76B becomes negative pressure, and this negative pressure replenishes the cleaning liquid from the cleaning liquid main tank 76A to the cleaning liquid sub-tank 76B. In response to not receiving the detection signal from the first liquid level sensor 303 (S29: No), the controller 130 continues to drive the negative pressure pump 193 (S28). In response to receiving the detection signal from the first liquid level sensor 303 (S29: Yes), the controller 130 closes the tank connection valve 302 (S30).

The controller 130 stops the negative pressure pump 193 (S31). This completes the cleaning liquid replenishment process. At this time, there is a risk that the cleaning liquid in the cleaning liquid sub-tank 76B may flow toward the ink sub-tank 181 through the connection channel 301 due to the negative pressure in the ink sub-tank 181. However, since the tank connection valve 302 is closed, the cleaning liquid may It does not flow into the sub tank 181.

[Movement of maintenance mechanism 60]
As shown in FIGS. 13 and 14, the maintenance mechanism 60 is supported by the first support mechanism 51 and the second support mechanism 52 and is in the second attitude. It can be moved to the standby position along the inclination direction 6 by sliding it. That is, the first support mechanism 51 and the second support mechanism 52 can support the maintenance mechanism 60 located at the maintenance position, the standby position, and between these two positions.

Specifically, the controller 130 first drives the first motor 55. As a result, the gear 106 rotates clockwise, so the gear 105 rotates counterclockwise, and the maintenance mechanism 60 in the maintenance position moves in the forward tilt direction 5 and is transferred onto the second support mechanism 52.

Controller 130 drives second motor 56 . As a result, the gear 120 rotates clockwise, the gears 118 and 119 rotate counterclockwise, and the maintenance mechanism 60 that has slid from the first support mechanism 51 reaches the standby position on the second support mechanism 52. (See Figure 14).

Controller 130 drives vertical drive motor 163. As a result, the screw shaft 161 rotates, so the second support mechanism 52 moves upward from the standby position along the orthogonal direction 10, and the maintenance mechanism 60 reaches the retreat position. As a result, the lips 66A, 66B, 66C of the caps 62A, 62B, 62C and the rubber wipers 63A, 63B, 63C come into contact with the wiper cleaning mechanism 80.

[Image recording processing]
Below, the process when an image is recorded on the sheet S (image recording process) will be explained.

When the controller 130 receives a command to record an image on the sheet S from an external device such as the operation panel 44 or an information processing device connected to the image recording device 100 via a LAN, the controller 130 starts the maintenance mechanism 60 as described above. Move from maintenance position to standby position. The controller 130 then drives the vertical drive motor 163 to move the maintenance mechanism 60 from the standby position to the retreat position. The controller 130 drives the shaft motor 59 to change the attitude of the first support mechanism 51 from the second attitude to the first attitude.

Next, the controller 130 moves the head 38 downward from the capped position to the recording position. Then, the controller 130 starts transporting the sheet S, executes a liquid circulation process to be described later, and discharges ink from the nozzle 38A with the sheet S positioned directly below the head 38. As a result, an image is recorded on the sheet S. The ink deposited on the sheet S is heated when passing through the heater 39 and is fixed on the sheet S. The further conveyed sheet S is checked for recorded images by the CIS 25, and then cut into a predetermined size by the cutter unit 26 and discharged.

After the image recording process on the sheet S, when the maintenance mechanism 60 moves to the maintenance position, the above-mentioned reverse process is performed.

[Liquid circulation processing]
The liquid circulation process when the image recording process is performed will be described below.

As shown in FIG. 16, the controller 130 closes the bypass valve 189 and the tank connection valve 302 (S41). The controller 130 drives the positive pressure pump 191 and the negative pressure pump 193 (S42). This creates a pressure difference between the head 38 and the ink sub-tank 181, and due to this pressure difference, ink circulates between the head 38 and the ink sub-tank 181 through the channels 183 and 184. At this time, the inside of the ink sub-tank 181 becomes negative pressure, so there is a risk that the cleaning liquid in the cleaning liquid sub-tank 76B will flow into the ink sub-tank 181 through the connection channel 301 due to this negative pressure. Therefore, the cleaning liquid does not flow into the ink sub-tank 181.

The controller 130 continues to drive the positive pressure pump 191 and the negative pressure pump 193 (S42) until it receives a power OFF signal in response to the user's power OFF operation (S43: No). The controller 130 stops the positive pressure pump 191 and the negative pressure pump 193 in response to receiving the power OFF signal in response to the user's power OFF operation (S43: Yes) (S13). This completes the liquid circulation process.

[Operations and effects in embodiments]
In the image recording apparatus 100, when the inside of the cleaning liquid sub-tank 76B becomes negative pressure by the negative pressure pump 193, the cleaning liquid is supplied from the cleaning liquid main tank 76A to the cleaning liquid sub-tank 76B by this negative pressure (cleaning liquid replenishment process). On the other hand, when a pressure difference is generated between the head 38 and the ink sub-tank 181 by the positive pressure pump 191 and the negative pressure pump 193, this pressure difference causes liquid to flow between the head 38 and the ink sub-tank 181 through the channels 183 and 184. is circulated (cleaning liquid circulation process). In this way, the negative pressure pump 193 is used for both cleaning liquid supply and liquid circulation, so compared to the case where a negative pressure pump for liquid circulation is provided separately from the negative pressure pump for cleaning liquid supply, Image recording device 100 is downsized.

In the image recording apparatus 100, since the cleaning liquid sub-tank 76B and the ink sub-tank 181 are connected by the connection channel 301, there is a possibility that the cleaning liquid flows from the cleaning liquid sub-tank 76B into the ink sub-tank 181 through the connection channel 301. In the image recording apparatus 100, when the liquid circulation process is executed, the tank connection valve 302 is closed, so that the cleaning liquid is prevented from flowing into the ink sub-tank 181 from the cleaning liquid sub-tank 76B through the connection channel 301.

In the image recording apparatus 100, when the cleaning liquid supply process is executed, the atmosphere release valve 190 is closed, so that air hardly flows from the cleaning liquid sub-tank 76B to the ink sub-tank 181 through the connection channel 301. Therefore, the cleaning liquid is prevented from flowing into the ink sub-tank 181 from the cleaning liquid sub-tank 76B through the connection channel 301.

In the image recording apparatus 100, if the tank connection valve 302 is open when the controller 130 stops the negative pressure pump 193 to end the cleaning liquid supply process, the negative pressure in the ink sub-tank 181 causes the cleaning liquid sub-tank 76B to drain. There is a possibility that the cleaning liquid may flow into the ink sub-tank 181 through the connection channel 301. In the image recording apparatus 100, when the negative pressure pump 193 is stopped in the cleaning liquid supply process, the tank connection valve 302 is closed, so the negative pressure in the ink subtank 181 causes the cleaning liquid in the cleaning liquid subtank 76B to flow into the connecting flow path. Flowing into the ink sub tank 181 through the ink tank 301 is suppressed.

In the image recording apparatus 100, since the negative pressure pump 193 is driven when the empty suction process is executed, the air in the cleaning liquid sub-tank 76B is discharged to the outside through the negative pressure pump 193. Therefore, the cleaning liquid in the cleaning liquid sub-tank 76B is prevented from flowing into the ink sub-tank 181 through the connection channel 301 during the empty suction process.

In the image recording apparatus 100, when the return pump 75 is stopped to end the empty suction process, the cleaning liquid in the cleaning liquid sub-tank 76B passes through the connection flow path 301 to the ink sub-tank 181 due to the slightly accumulated pressure in the cleaning liquid sub-tank 76B. There is a risk of an influx. In the image recording apparatus 100, the return pump 75 is stopped after the tank connection valve 302 is closed, so the pressure in the cleaning liquid sub-tank 76B causes the cleaning liquid in the cleaning liquid sub-tank 76B to be returned to the cleaning liquid main tank 76A. As a result, the pressure within the cleaning liquid sub-tank 76B is reduced. Therefore, when the cleaning liquid supply process of opening the tank connection valve 302 and driving the negative pressure pump 193 is executed, the pressure inside the cleaning liquid sub-tank 76B prevents the cleaning liquid from flowing into the ink sub-tank 181 through the connection channel 301. be done.

In the image recording apparatus 100, one end 301A of the connection channel 301 opens to the upper wall 76BB of the cleaning liquid sub-tank 76B, so that the cleaning liquid does not easily flow out from the cleaning liquid sub-tank 76B to the connection channel 301. Therefore, the cleaning liquid is prevented from flowing into the ink sub-tank 181 from the cleaning liquid sub-tank 76B through the connection channel 301.

In the image recording apparatus 100, the other end 301B of the connection channel 301 is open to the upper wall 181A of the ink sub-tank 181, so that ink is suppressed from flowing out from the ink sub-tank 181 to the connection channel 301.

[Modified example]
In the image recording apparatus 100, the support base 61 is provided with three caps 62A, 62B, and 62C, but the number of caps 62 is not particularly limited as long as it corresponds to the number of ejection modules 49A. For example, the number of caps 62 may be four or more, or two or less. Further, the sponge wiper 64 and the rubber wiper 63 are not essential components.

In the image recording apparatus 100, the maintenance mechanism 60 moves along the front-rear direction 8, but the movement of the maintenance mechanism 60 is not particularly limited. Further, the discharge module 49 may be moved relative to the maintenance mechanism 60.

38... Head 64... Sponge wiper 74... Suction pump 75... Return pump 76A... Cleaning liquid main tank 76B... Cleaning liquid sub tank 100... Image recording device 130... Controller 153. ...Liquid channel 175...First supply tube 176...Return tube 181...Ink sub-tank 183...Flow path 184...Flow path 185...Atmospheric communication path 190...Open to atmosphere Valve 191...Positive pressure pump 193...Negative pressure pump 301...Connection channel 301A...One end 301B...Other end 302...Tank connection valve

Claims (8)

A tank for storing liquid,
a head having a nozzle that discharges the liquid supplied from the tank;
A cleaning liquid main tank that stores cleaning liquid,
A cleaning liquid sub-tank connected to the cleaning liquid main tank,
a first flow path and a second flow path connecting the tank and the head;
a third flow path connecting the tank and the cleaning liquid sub-tank;
a positive pressure pump that applies pressure to the liquid in a direction toward the head in the first flow path;
A liquid discharging device comprising: a negative pressure pump connected to the third flow path to create a negative pressure in the tank and the cleaning liquid sub-tank. a tank connection valve disposed between the cleaning liquid sub-tank and the negative pressure pump in the third flow path;
further comprising a controller;
The liquid discharging device according to claim 1, wherein the controller closes the tank connection valve when executing liquid circulation processing to drive the negative pressure pump and the positive pressure pump. an atmospheric communication path connected to the tank and communicating with the atmosphere;
further comprising an atmosphere release valve that opens and closes the atmosphere communication passage;
The liquid discharging device according to claim 2, wherein the controller closes the atmosphere release valve when executing a cleaning liquid supply process in which the tank connection valve is opened and the negative pressure pump is driven. The liquid discharging device according to claim 3, wherein the controller stops the negative pressure pump after closing the tank connection valve. a wiper; a wiper channel that circulates the wiper and the cleaning liquid sub-tank;
a wiper pump that circulates cleaning liquid from the cleaning liquid sub-tank to the wiper in the wiper flow path,
5. The liquid discharging device according to claim 2, wherein the controller drives the negative pressure pump when executing a dry suction process in which the tank connection valve is opened with the wiper pump being driven. 6. The liquid discharging device according to claim 5, wherein the controller stops the wiper pump after closing the tank connection valve when stopping the wiper pump to end the empty suction process. 7. The liquid discharging device according to claim 1, wherein one end of the third flow path opens at an upper wall of the cleaning liquid sub-tank. 8. The liquid discharging device according to claim 1, wherein the other end of the third flow path opens at the upper wall of the tank.

Images