Liquid dispensing device, control program, and wiper cleaning method

Abstract

The present invention provides a liquid dispensing device that can remove liquid adhering to a wiper during nozzle surface cleaning. [Solution] The liquid discharge device 100 includes a wiper 60 having an impregnation part 76 for impregnating with cleaning liquid, a wiper body 61 for wiping the nozzle surface 40a, and a body holder for supporting the wiper body 61, and a wiper moving mechanism 70 for moving the wiper body 61 between a separated position P1 where the wiper body 61 is away from the impregnation part 76 and a contact position P2 where the wiper body 61 contacts the impregnation part 76. The controller 9 moves the discharge head 4 to a predetermined cleaning liquid discharge position PB facing the impregnation part 76 in the passage region A, and then performs an impregnation process in which droplets of cleaning liquid are discharged from the first nozzle 41 to the impregnation part 76 at the predetermined cleaning liquid discharge position PB, and after the impregnation process is performed, moves the wiper body 61 from the separated position P1 to the contact position P2 to clean the wiper body 61.

Description

Technical Field

[0005]

[0001] The present invention relates to a liquid ejection device, a control program, and a wiper cleaning method.

Background Art

[0002] Patent Document 1 discloses a liquid ejection device including a wiper member for wiping a discharge surface and a cleaning member for removing liquid adhering to the wiper member by contacting the wiper member, and capable of performing cleaning to remove the liquid adhering to the wiper member by bringing the wiper member into contact with the cleaning member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in recent years, there has been a tendency to use highly viscous ink, and there has been a risk that the wiper cannot be sufficiently cleaned only by bringing the wiper member into contact with the cleaning member.

Means for Solving the Problems

[0005] To solve the above problems, a liquid dispensing device according to one aspect of the present invention includes a dispensing head having a nozzle plate with a first nozzle which is an opening for dispensing droplets of cleaning liquid and a second nozzle which is an opening for dispensing droplets of a predetermined liquid different from the cleaning liquid; a dispensing head drive unit for dispensing the droplets from the first nozzle and the second nozzle; a head moving mechanism for moving the dispensing head in the moving direction; an impregnation unit positioned opposite the passage region which is the region through which the nozzle surface of the nozzle plate passes as the dispensing head moves, and impregnating the cleaning liquid; a wiper body for wiping the nozzle surface; and The device comprises a wiper having a body holder that supports the wiper body, a wiper movement mechanism that moves the wiper body between a spaced position away from the impregnation portion and a contact position where the wiper body contacts the impregnation portion, and a controller, wherein the controller moves the discharge head to a predetermined cleaning liquid discharge position facing the impregnation portion in the passage region, and then performs an impregnation process in which droplets of the cleaning liquid are discharged from the first nozzle to the impregnation portion at the predetermined cleaning liquid discharge position, and after the execution of the impregnation process, performs a cleaning process in which the wiper body is moved from the spaced position to the contact position and the wiper body is cleaned.

[0006] This configuration allows for the removal of liquid adhering to the wiper during nozzle surface cleaning. [Effects of the Invention]

[0007] The present invention has the effect of being able to remove liquid adhering to the wiper during cleaning of the nozzle surface. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic plan view showing an example of the configuration of a liquid dispensing device according to Embodiment 1. [Figure 2] Figure 1 shows a cross-sectional view of the discharge head of the liquid dispensing device and a schematic front view illustrating an example of the maintenance section configuration. [Figure 3] Figure 1 is a perspective view showing an example of the configuration of the rotating cam of the liquid dispensing device. [Figure 4] Figure 1 is a schematic diagram showing an example of the configuration of the suction mechanism of the liquid dispensing device. [Figure 5] Figure 1 is a block diagram showing the functional configuration of the liquid dispensing device. [Figure 6] Figure 1 is a flowchart illustrating an example of the maintenance operation of the liquid dispensing device. [Figure 7] Figure 1 is a flowchart illustrating an example of the operation of the suction purging process of the liquid discharge device. [Figure 8A] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8B] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8C] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8D] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8E] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8F] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8G] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8H] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 8I] Figure 1 is a schematic front view illustrating an example of the operation of the liquid dispensing device. [Figure 9] This flowchart shows an example of the operation of the liquid dispensing device according to Embodiment 2. [Figure 10] This is a flowchart showing an example of the operation of the liquid dispensing device according to Embodiment 3. [Figure 11] This graph shows the correlation between ambient temperature and humidity and the time used to determine whether or not to perform impregnation treatment during the maintenance operation of the liquid dispensing device according to Embodiment 3. [Figure 12] This flowchart shows an example of the operation of the liquid dispensing device according to Embodiment 4. [Figure 13] It is a flowchart showing an operation example of the liquid ejection device according to Embodiment 5. [Figure 14] It is a flowchart showing an operation example of the liquid ejection device according to Embodiment 6. [Figure 15] It is a flowchart showing an operation example of the liquid ejection device according to Embodiment 7. [Figure 16] It is a flowchart showing an operation example of the liquid ejection device according to Embodiment 8.

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments will be described with reference to the drawings. Note that the present invention is not limited by the following embodiments. Also, in the following, throughout all the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions thereof are omitted.

[0010] The functions of the elements disclosed in this specification can be executed using a circuit or processing circuit including a general-purpose processor, a dedicated processor, an integrated circuit, an ASIC (Application Specific Integrated Circuits), a conventional circuit, and / or a combination thereof configured or programmed to execute the disclosed functions. Since a processor includes transistors and other circuits, it is regarded as a processing circuit or a circuit. In the present disclosure, a circuit, unit, or means is hardware that executes the listed functions or hardware programmed to execute the listed functions. The hardware may be the hardware disclosed in this specification or other known hardware programmed or configured to execute the listed functions. When the hardware is a processor considered to be a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used in the configuration of the hardware and / or the processor.

[0011] (Embodiment 1) Figure 1 is a schematic plan view showing an example of the configuration of a liquid ejection device 100 according to Embodiment 1. The liquid ejection device 100 is a device that prints an image onto a recording medium 110 using droplets ejected from an ejection head 4 based on image data. In the following, an inkjet printer that ejects ink as droplets will be described as the liquid ejection device 100. In this embodiment, the ink is a pigment ink containing solid components. The solid components of the ink include resin fine particles and solid components of colorants. The resin fine particles are contained in the ink in a range of 0.1 wt% to 30 wt%. The solid components of colorants are contained in the ink in a range of 0.1 wt% to 20 wt%. The liquid ejection device 100 can eject cyan, magenta, and yellow inks as droplets. The liquid ejection device 100 can also eject a cleaning solution for cleaning the ejection head 4 as droplets. The cleaning solution is a liquid that does not contain solid components.

[0012] As shown in Figure 1, the liquid ejection device 100 is a serial head type inkjet printer. In the printing process, the ejection head 4 moves (scans) in the movement direction D2 while ejecting droplets in the ejection direction D1 (see Figure 2) to form an image on the recording medium 110, and the recording medium 110 is transported in the transport direction D3, which are performed alternately. In the liquid ejection device 100, the ejection direction D1, the movement direction D2, and the transport direction D3 are orthogonal to each other. However, this is not limited to this, and the ejection direction D1, the movement direction D2, and the transport direction D3 may intersect each other. For the sake of explanation, in the following, the movement direction D2 may be referred to as the left-right direction, and the transport direction D3 may be referred to as the front-back direction. Also, in the ejection direction D1, the side from which droplets are ejected may be referred to as downward, and the opposite side may be referred to as upward.

[0013] The liquid dispensing device 100 comprises a housing 10, a platen 11, a transport unit 12, a head moving mechanism 2, a tank 3, a dispensing head 4, a supply channel 15, a maintenance unit 5, a temperature measuring unit 16, a humidity measuring unit 17, and a controller 9.

[0014] The discharge head 4 is housed within the housing 10 of the liquid discharge device 100. The discharge head 4 includes a nozzle plate 40 and a discharge head drive unit 45.

[0015] The nozzle plate 40 has multiple nozzle rows 42, each containing multiple nozzles 41 arranged in the transport direction D3. The multiple nozzle rows 42 are arranged at predetermined intervals in the movement direction D2. The nozzle plate 40 has a nozzle surface 40a facing downward. Each nozzle 41 is open to the nozzle surface 40a. Each nozzle 41 ejects a droplet downward toward the recording medium 110 based on image data.

[0016] The multiple nozzle rows 42 are divided into multiple groups aligned in the direction of movement D2. The number of groups corresponds to the number of types of liquid discharged by the liquid discharge device 100, and in this embodiment there are four. The group located at one end of the direction of movement D2 is the cleaning liquid discharge nozzle row 42a, which consists of cleaning liquid discharge nozzles 41a. More specifically, the one end of the direction of movement D2 is the inward direction, which will be described later. The cleaning liquid discharge nozzles 41a are openings for discharging droplets of cleaning liquid. The other three groups are the ink discharge nozzle row 42b, which consists of ink discharge nozzles 41b. The ink discharge nozzles 41b in these three groups are openings for discharging droplets of cyan, magenta, and yellow ink, respectively. Thus, the cleaning liquid discharge nozzles 41a, the cyan ink discharge nozzles 41b, the magenta ink discharge nozzles 41b, and the yellow ink discharge nozzles 41b are aligned from one end to the other in the direction of movement D2. The cleaning fluid discharge nozzle 41a and the cleaning fluid discharge nozzle row 42a discharge droplets in the discharge direction D1.

[0017] Figure 2 is a schematic front view showing a cross-sectional view of the discharge head 4 and an example of the configuration of the maintenance unit 5. As shown in Figure 2, the discharge head drive unit 45 has drive elements provided on each of the nozzles 41. The drive element provided on the cleaning liquid discharge nozzle 41a is driven to apply pressure to the cleaning liquid inside the cleaning liquid discharge nozzle 41a, causing droplets of cleaning liquid to be discharged from the cleaning liquid discharge nozzle 41a in the discharge direction D1. Similarly, the drive element provided on the ink discharge nozzle 41b is driven to apply pressure to the ink inside the ink discharge nozzle 41b, causing droplets of ink to be discharged from the ink discharge nozzle 41b in the discharge direction D1.

[0018] As shown in Figure 1, the platen 11 is a plate positioned opposite the nozzle surface 40a of the discharge head 4. The platen 11 is located below the discharge head 4 at a predetermined distance. The upper surface of the platen 11 is flat. The upper surface of the platen 11 supports the recording medium 110 from below.

[0019] The transport unit 12 transports the recording medium 110 on the platen 11 in the transport direction D3. The transport unit 12 has two transport rollers 13 and a transport motor. The two transport rollers 13 extend in the direction of movement D2 and, when viewed from above, are positioned apart in the transport direction D3 with the platen 11 in between. Each transport roller 13 is connected to the rotation axis of the transport motor via a reduction gear. Therefore, the two transport rollers 13 rotate around their axes when driven by the transport motor, transporting the recording medium 110 on the platen 11 in the transport direction D3.

[0020] The head movement mechanism 2 moves the discharge head 4 back and forth in the movement direction D2. The head movement mechanism 2 includes a carriage 21 and a carriage drive unit 22.

[0021] The carriage 21 supports the discharge head 4 and moves back and forth in the direction of movement D2. The carriage drive unit 22 moves the carriage 21. The carriage drive unit 22 includes two guide rails 26, two pulleys 28, an endless belt 27, and a move motor 29. The maintenance area M is located on the other side of the direction of movement D2 of the platen 11. The other side of the direction of movement D2 is the outward direction, which will be described later. When viewed from above, the two guide rails 26 extend in the direction of movement D2 so as to pass through the platen 11 and the maintenance area M, and are positioned apart in the conveying direction D3. The two guide rails 26 support the carriage 21 and guide the carriage 21 in the direction of movement D2. The two pulleys 28 are provided near both ends of one of the guide rails 26. One of the pulleys 28 is connected to the rotating shaft of the move motor 29 via a reduction gear. The endless belt 27 is wrapped around the two pulleys 28. The carriage 21 is then connected to a predetermined location on the endless belt 27.

[0022] Therefore, the drive of the moving motor 29 causes the endless belt 27 to revolve around the two pulleys 28, and the carriage 21 supporting the discharge head 4 moves along the guide rail 26 in the direction of movement D2. Furthermore, by controlling the rotational angle position of the rotation axis of the moving motor 29, the carriage 21 and the discharge head 4 can be positioned within the reciprocating movement range at a position corresponding to the rotational angle position of the rotation axis of the moving motor 29. In this way, the head moving mechanism 2 can position the discharge head 4 at any position on the platen 11 and in the maintenance area M. As shown in Figure 2, the area through which the nozzle surface 40a passes as the discharge head 4 moves is the passage area A.

[0023] Tank 3 contains the liquid supplied to the dispensing head 4. Tank 3 is, for example, a cartridge-type tank and is held in a predetermined position within the housing 10. Tank 3 includes a cleaning fluid tank 31 and a number of ink tanks 32 corresponding to the ink colors. The cleaning fluid tank 31 contains the cleaning fluid. The ink tanks 32 contain the ink. Tank 3 is covered by an openable and closable cover provided on the housing 10. Tank 3 can be attached to or removed from the liquid dispensing device 100 by opening the cover.

[0024] The supply channel 15 is a channel that supplies the liquid stored in the tank 3 to the nozzle 41. The temperature measuring unit 16 is a sensor that measures the ambient temperature. The humidity measuring unit 17 is a sensor that measures the ambient humidity.

[0025] <Maintenance Department> The maintenance unit 5 will be described in detail below. In the following, of the movement direction D2, the side moving from the platen 11 toward the maintenance area M when viewed from the discharge direction D1 will be referred to as the outward direction, and the opposite direction, the side moving from the maintenance area M toward the platen 11, will be referred to as the inward direction. Figures 8A to 8I are schematic front views showing examples of the operation of the maintenance unit 5 of the liquid discharge device 100.

[0026] As shown in Figures 1 and 2, the maintenance unit 5 cleans the nozzle surface 40a and the nozzle 41, and prevents the ink inside the nozzle 41 from drying out. The maintenance unit 5 is located in the maintenance area M. The maintenance unit 5 includes a frame 50, a cap 55, a lifting mechanism 59, a wiper 60, a wiper moving mechanism 70, a cleaning unit 75, and a suction mechanism 80 (see Figure 4).

[0027] The frame 50 supports the cap 55, the wiper 60, and the cleaning section 75. The frame 50 includes a pair of side walls 52 facing the transport direction D3, and a connecting section 54 connecting the pair of side walls 52. Each side wall 52 includes a guide section 53 which is an elongated hole or notch extending in the discharge direction D1. The guide section 53 has a lower end. The guide section 53 of one side wall 52 and the guide section 53 of the other side wall 52 overlap when viewed from the transport direction D3. The connecting section 54 extends in the transport direction D3 and connects the pair of side walls 52. The connecting section 54 has an upper surface 54a, a guide surface 54b, and an elastic body mounting section 54c. The upper surface 54a is an upward-facing surface that extends in the movement direction D2 and the transport direction D3. The guide surface 54b is an outward-facing surface that extends downward from the outer end of the upper surface 54a. The elastic body mounting portion 54c is located below and inward from the lower end of the guide portion 53.

[0028] The cap 55 contacts the nozzle plate 40 of the discharge head 4, which is located at a predetermined maintenance position PC, and covers the nozzle 41. The cap 55 includes a cap body 56 and a cap holder 57. The cap body 56 is a box-shaped body with a bottom and an open top. The opening edge of the top surface of the cap body 56 extends parallel to the nozzle surface 40a. The cap body 56 is made of a flexible material. The cap body 56 is divided into two spaces by a partition that extends in the transport direction D3. Of the two spaces, the inner space is the first cap portion 56a, which covers the cleaning liquid discharge nozzle 41a. The outer space is the second cap portion 56b, which covers the three ink discharge nozzles 41b together. Suction ports 56c are formed at the bottom of the first cap portion 56a and the second cap portion 56b, respectively.

[0029] The cap holder 57 supports the cap body 56 from below. The cap holder 57 moves up and down relative to the frame 50. As a result, the cap 55 moves up and down within a range that includes the range from the raised position Pu shown in Figure 2 to the lowered position Pd below the raised position Pu shown in Figure 8B. The raised position Pu is the position where the upper end of the cap body 56 abuts against and is in close contact with the nozzle surface 40a of the discharge head 4, which is located in the maintenance position PC. When the upper end of the cap body 56 is in close contact with the nozzle surface 40a of the discharge head 4, the first cap portion 56a covers the cleaning liquid discharge nozzle 41a, and the internal space becomes a sealed space. The second cap portion 56b also covers the ink discharge nozzle 41b, and the internal space becomes a sealed space. The lowered position Pd is the position where the upper end of the cap body 56 is away from the nozzle surface 40a of the discharge head 4. The cap holder 57 has an engaging recess 57a which is connected to an engaging projection 78a of the cleaning unit 75, which will be described later.

[0030] The lifting mechanism 59 raises and lowers the cap holder 57. The lifting mechanism 59 includes a cam and a motor that rotates the cam. When the motor rotates the cam, the cam raises and lowers the cap holder 57, causing the cap 55 to move up and down.

[0031] The wiper 60 wipes the nozzle surface 40a of the discharge head 4. The wiper 60 is located inward of the cap 55. The wiper 60 includes a wiper body 61 and a body holder 62.

[0032] The wiper body 61 is a plate-shaped member for wiping the nozzle surface 40a. The material of the wiper body 61 is a flexible material such as rubber or synthetic resin. The wiper body 61 has its longitudinal direction oriented in the transport direction D3, its short direction oriented in the vertical direction, and has an outer surface facing outward and an inner surface facing inward. When the wiper body 61 wipes the nozzle surface 40a, the upper end of the outer surface of the wiper body 61 comes into contact with the nozzle surface 40a. The longitudinal dimension of the wiper body 61 is longer than the dimension of the nozzle row 42 in the transport direction D3. The wiper body 61 extends vertically when viewed from the transport direction D3.

[0033] The main body holder 62 supports the wiper body 61. The main body holder 62 includes a head 63, a back plate 67, an arm 64, a tooth stopper 65, and a pivot shaft 66. The head 63 extends in the transport direction D3. The lower end of the wiper body 61 is fixed entirely to the upper end of the head 63. The wiper body 61 extends upward from the upper end of the head 63. The back plate 67 is a plate whose lower end is continuous with the head 63 and extends upward. The back plate 67 is fitted to the outer surface of the wiper body 61. As a result, the wiper body 61 can be deformed so that the entire body from the lower end to the upper end curves significantly inward in the inward direction. On the other hand, in the outward direction, the back plate 67 restricts the deformation so that the entire body from the lower end to the upper end curves significantly inward. Also, the upper end of the wiper body 61 is located above the upper end of the back plate 67. Therefore, when viewing the wiper 60 from the outside, the upper end of the wiper body 61 protrudes from the upper end of the back plate 67.

[0034] The arm 64 is an arm that extends downward from the center of the lower surface of the head 63, and has a pair of side surfaces aligned in the transport direction D3 and an inner surface facing inward. The pivot shaft 66 is a pair of coaxial projections that protrude out of plane from the pair of side surfaces of the arm 64. The pivot shaft 66 is fitted into a pair of guide parts 53. Therefore, the wiper 60 moves in the vertical direction, which is the direction in which the guide parts 53 extend to the frame 50. The wiper 60 also swings around the pivot shaft 66.

[0035] The stopper portion 65 is a projection that protrudes inward from the inner surface of the arm 64. The stopper portion 65 is shaped so that it can be hooked onto the upper surface 54a of the connecting portion 54. By moving the wiper 60 upward and hooking the stopper portion 65 onto the upper surface 54a of the connecting portion 54, the downward movement of the wiper 60 is restricted.

[0036] The wiper moving mechanism 70 performs the function of moving the wiper 60. The wiper moving mechanism 70 includes an elastic body 71, a rotating cam 72, and an actuator.

[0037] The elastic body 71 generates a restoring force when subjected to a tensile load. The elastic body 71 is, for example, a tension spring. One end of the elastic body 71 is attached to the inner surface of the arm 64 at a position above the pivot axis 66. The other end of the elastic body 71 is attached to the elastic body mounting portion 54c. The elastic body 71 is mounted under a tensile load. Therefore, the elastic body 71 imparts a biasing force to the wiper 60 having an inward component and a downward component. In the initial state, the wiper 60 is positioned at the standby position P1 shown in Figure 2, under the biasing force of the elastic body 71. In the standby position P1, the wiper 60 assumes a posture in which the pivot axis 66 of the wiper 60 abuts against the lower ends of the pair of guide portions 53, and the tooth stop portion 65 abuts against the guide surface 54b.

[0038] The rotating cam 72 is a cam for moving the wiper 60 and rotates in one direction by the driving force of the actuator. The rotating cam 72 is located below the wiper 60 and rotates around a pivot axis L that extends in the vertical direction. Figure 3 is a perspective view showing an example of the configuration of the rotating cam 72. As shown in Figure 3, the rotating cam 72 includes a disc portion 72a, a cylindrical portion 72b, a lifting / lowering operating portion 72c, and a lowering / lowering operating portion 72d. The disc portion 72a is an annular plate with the pivot axis L as its central axis. The arm 64 is located above the disc portion 72a. The cylindrical portion 72b is a cylinder with the pivot axis L as its central axis, and its lower end is continuous with the inner circumference of the disc portion 72a.

[0039] The lifting mechanism 72c rises upward from the disc portion 72a. The lifting mechanism 72c is provided over a predetermined angular range in the circumferential direction around the pivot axis L. When the rotating cam 72 rotates, the arm 64 of the wiper 60 rides up onto the upstream end of the lifting mechanism 72c in the direction of rotation. Then, as shown in Figure 2, the wiper 60 moves upward guided by a pair of guide portions 53 against the biasing force of the elastic body 71. At this time, the wiper 60 receives the inward component of the biasing force of the elastic body 71, causing the stopper portion 65 to slide on the guide surface 54b. When the wiper 60 rises and the stopper portion 65 passes the upper end of the guide surface 54b, the wiper 60 rotates in the circumferential direction around the pivot axis 66, receiving the inward component of the biasing force of the elastic body 71, and the inner surface of the main body holder 62 comes into contact with the guide surface 54b. Subsequently, as the arm 64 of the wiper 60 approaches the downstream end of the lifting mechanism 72c in the rotational direction, the wiper 60 descends due to the downward biasing force component of the elastic body 71. As the wiper 60 descends, the stopper 65 contacts and catches on the upper surface 54a of the connecting part 54. This restricts the downward movement of the wiper 60. As shown in Figure 8A, the position where the stopper 65 catches on the upper surface 54a of the connecting part 54 is the wiping position P2. Thus, the wiping position P2 is located above the standby position P1. At the wiping position P2, the upper end of the wiper body 61 passes through the passage area A and is located above the passage area A. Therefore, the moving discharge head 4 contacts the wiper body 61 located at the wiping position P2. As shown in Figure 8C, the position where the discharge head 4, moving outward, contacts the wiper body 61 located at the wiping position P2 is the release position PA of the discharge head 4. Thus, the tooth stop portion 65 performs the function of allowing the wiper 60 to move from the standby position P1 to the wiping position P2 and restricting its movement from the wiping position P2 to the standby position P1. The shape of the lifting and lowering operating portion 72c is defined so that the tooth stop portion 65 rises above the upper surface 54a.

[0040] Furthermore, as shown in Figure 8D, when the wiper body 61, located in the wiping position P2, is rotated circumferentially around the pivot axis 66 so as to tilt outward, the stopper portion 65 disengages from the upper surface 54a of the connecting portion 54. As a result, the wiper 60 moves downward due to the downward component of the biasing force of the elastic body 71. As a result, the wiper 60 moves to the standby position P1, as shown in Figure 8E.

[0041] As shown in Figure 3, the tilting mechanism 72d is provided over an angular range in the circumferential direction around the pivot axis L that is different from and separate from the angular range in which the lifting mechanism 72c is provided. The tilting mechanism 72d protrudes radially outward from the outer circumferential surface of the cylindrical portion 72b. When the rotating cam 72 rotates, the arm 64 of the wiper 60, which is located in the standby position P1, rides up onto the upstream end of the tilting mechanism 72d in the direction of rotation, causing the lower end of the arm 64 to move inward and the upper end of the arm 64 to move outward. As a result, the wiper body 61 rotates in the circumferential direction around the pivot axis 66 and tilts outward. As the wiper body 61 tilts outward, the upper end of the arm 64 and the wiper body 61 move outward. The shape of the tilting mechanism 72d is defined so that the wiper body 61 is located at a predetermined contact position P3 as shown in Figure 8G.

[0042] Thus, the wiper movement mechanism 70 moves the wiper body 61 between a wiping position P2 where the wiper body 61 is positioned advanced within the passage area A and a standby position P1 where the wiper body 61 is positioned retracted outside the passage area A. The wiper movement mechanism 70 also moves the wiper body 61 between a standby position P1 where the wiper body 61 is positioned away from the impregnation portion 76 and a contact position P3 where the wiper body 61 is in contact. In other words, the standby position P1 is a position where the wiper body 61 is waiting outside the passage area A, and is also a position where the wiper body 61 is positioned away from the impregnation portion 76.

[0043] As shown in Figure 2, the cleaning unit 75 has the function of cleaning the wiper body 61. The cleaning unit 75 is located in the direction of the inside of the cap 55 and outward of the wiper 60. The cleaning unit 75 includes an impregnation unit 76, a blade unit 77, and a support unit 78.

[0044] The impregnated portion 76 is made of a flexible, porous material, such as a foamed synthetic resin. The impregnated portion 76 can be impregnated with cleaning liquid. The upper surface of the impregnated portion 76 is positioned opposite the passage area A. Also, as shown in Figure 8E, the cleaning liquid discharge position PB of the discharge head 4 is defined above the impregnated portion 76. The cleaning liquid discharge position PB is the position where, when the cleaning liquid discharge nozzle row 42a of the discharge head 4, which is moving outward, discharges droplets of cleaning liquid at this position PB, they land on the upper surface of the impregnated portion 76. Therefore, in the outward direction of movement D2, the release position PA, the cleaning liquid discharge position PB, and the maintenance position PC are arranged in this order.

[0045] The blade portion 77 is a plate extending in the vertical direction and the conveying direction D3, with its lower end being the cutting edge. The blade portion 77 is located inward of the impregnation portion 76. The lower end of the blade portion 77 is located above the lower end of the side surface facing inward of the impregnation portion 76.

[0046] The support portion 78 supports the impregnation portion 76 and the blade portion 77. The support portion 78 is a support column extending in the vertical direction. The support portion 78 has an engaging projection 78a extending outward. The engaging projection 78a engages with the engaging recess 57a of the cap holder 57 and is connected to the cap 55. Therefore, as the cap 55 moves up and down, the cleaning portion 75 moves up and down integrally with the cap 55 within a range that includes the range from the raised position Pu to the lowered position Pd.

[0047] Then, as shown in Figure 8F, the cutting edge of the blade portion 77 is located on the trajectory in which the wiper body 61 moves from the standby position P1 to the contact position P3. Therefore, when the wiper 60 swings between the standby position P1 and the contact position P3, the wiper body 61 comes into contact with the cutting edge of the blade portion 77 during the movement. When the wiper body 61 comes into contact with the cutting edge of the blade portion 77, the wiper body 61 elastically deforms and passes below the cutting edge of the blade portion 77. Then, as shown in Figure 8G, at the contact position P3, the surface of the wiper body 61 facing outward comes into contact with the surface of the impregnated portion 76 facing inward. The aforementioned contact position P3 is the position in which the wiper body 61 comes into contact with the impregnated portion 76.

[0048] Figure 4 is a schematic diagram showing an example configuration of the suction mechanism 80. As shown in Figure 4, the suction mechanism 80 performs purging of the discharge head 4. The suction mechanism 80 includes a first waste liquid passage 81, a second waste liquid passage 82, a third waste liquid passage 83, a suction pump 84, a switching valve 85, and a waste liquid tank 86.

[0049] The first waste liquid channel 81, the second waste liquid channel 82, and the third waste liquid channel 83 are pipelines, for example, tubes made of synthetic resin. The upstream end of the first waste liquid channel 81 is connected to the suction port 56c of the first cap section 56a, and the cleaning liquid flows downstream. The upstream end of the second waste liquid channel 82 is connected to the suction port 56c of the second cap section 56b, and the ink flows downstream. The downstream end of the third waste liquid channel 83 is connected to the waste liquid tank 86. The waste liquid tank 86 contains the cleaning liquid and ink flowing in from the third waste liquid channel 83.

[0050] The switching valve 85 is connected to the downstream ends of the first wastewater passage 81 and the second wastewater passage 82, and to the upstream end of the third wastewater passage 83. The switching valve 85 switches between a first state in which the first wastewater passage 81 and the third wastewater passage 83 are in communication, and a second state in which the second wastewater passage 82 and the third wastewater passage 83 are in communication. The suction pump 84 is located in the third wastewater passage 83 and generates negative pressure in the third wastewater passage 83 when it is operated. When the switching valve 85 is in the first state, it generates negative pressure in the first wastewater passage 81 which is in communication with the third wastewater passage 83. When the switching valve 85 is in the second state, it generates negative pressure in the second wastewater passage 82 which is in communication with the third wastewater passage 83. The first waste liquid passage 81, the second waste liquid passage 82, and the third waste liquid passage 83 are rubber tubes, which may be transparent, translucent, or colored. The suction pump 84 is, for example, a tube pump. The suction pump 84 generates negative pressure by squeezing the rubber tube that is the third waste liquid passage 83, and performs suction in either a first state where the first waste liquid passage 81 and the third waste liquid passage 83 are in communication, or a second state where the second waste liquid passage 82 and the third waste liquid passage 83 are in communication.

[0051] Figure 5 is a block diagram showing the functional configuration of the liquid dispensing device 100. As shown in Figure 5, the controller 9 has a functional configuration mainly consisting of hardware, including a control unit 91, a storage unit 92 connected to the control unit 91, and an interface 93. The control unit 91 is also connected to the aforementioned dispensing head drive unit 45, transport unit 12, head movement mechanism 2, wiper movement mechanism 70, lifting mechanism 59, switching valve 85, and suction pump 84.

[0052] The control unit 91 is, for example, a computer and includes circuits such as a processor like an MPU or an integrated circuit like an ASIC. The storage unit 92 is a memory accessed by the control unit 91 and includes, for example, RAM and ROM. Of these, the RAM temporarily stores image data and various data during calculations by the control unit 91. The ROM stores computer programs and data for various data processing. Therefore, the control unit 91 controls the operation of each part of the liquid dispensing device 100 by executing computer programs while referring to the data stored in the storage unit 92.

[0053] Interface 93 is a connection device that connects the control unit 91 to external devices of the liquid dispensing device 100. Examples of external devices include other computers, communication networks, recording media, displays, and other liquid dispensing devices. The liquid dispensing device 100 acquires image data and print setting information from external devices, such as computers, via this interface 93. This image data includes raster data representing an image to be printed on the recording media 110, which has RGB value gradation information.

[0054] The discharge head drive unit 45 has a nozzle drive circuit electrically connected to each drive element of the discharge head 4, and controls the operation of the drive elements of each nozzle 41 based on instructions from the control unit 91. That is, the control unit 91 outputs a control signal to drive the drive elements to the nozzle drive circuit, the nozzle drive circuit generates a drive signal based on the input control signal, and outputs this drive signal to each drive element. As a result, each drive element is driven based on the corresponding drive signal and operates to apply a predetermined discharge pressure to the liquid in the nozzle 41. Therefore, the control unit 91 can control the discharge timing of the droplets discharged from each nozzle 41, and the size of the discharged droplets (droplet volume). As a result, the discharge head 4 selectively discharges one of small-volume, medium-volume, and large-volume droplets from the cleaning liquid discharge nozzle 41a.

[0055] The transport unit 12 has a transport drive circuit that is electrically connected to the transport motor described above. The transport motor's operation is controlled by the control unit 91 via the transport drive circuit. This allows the transport unit 12 to transport the recording medium 110 on the platen 11 intermittently or continuously in the forward and backward directions. Furthermore, the transport unit 12 can stop and hold the recording medium 110 at a predetermined position on the platen 11.

[0056] The head movement mechanism 2 has a movement drive circuit electrically connected to the movement motor 29 described above. The operation of the movement motor 29 is controlled by the control unit 91 via the movement drive circuit. The head movement mechanism 2 can move the carriage 21 supporting the discharge head 4 in the movement direction D2 at any speed. Furthermore, the position of the carriage 21 supporting the discharge head 4 can be adjusted by controlling the rotational angle position of the movement motor 29. Therefore, the discharge head 4 mounted on the carriage 21 is moved back and forth in the movement direction D2 relative to the recording medium 110 by the head movement mechanism 2.

[0057] The wiper movement mechanism 70 has a cam drive circuit electrically connected to the actuator described above. The operation of the actuator is controlled by the control unit 91 via the cam drive circuit. As a result, the wiper movement mechanism 70 moves the wiper 60 between the standby position P1 and the wiping position P2, and between the standby position P1 and the contact position P3, which are separated positions, and positions the wiper 60 at the standby position P1, the wiping position P2, and the contact position P3.

[0058] The lifting mechanism 59 has a lifting drive circuit electrically connected to the motor described above. The motor's operation is controlled by the control unit 91 via the lifting drive circuit. As a result, the lifting mechanism 59 moves the cap body 56 that supports the cap 55 and the body holder 62 connected to the cap body 56 in the discharge direction D1, and positions the cap 55 in an elevated position Pu that contacts the nozzle surface 40a of the discharge head 4 located at the maintenance position PC, a lowered position Pd that separates the cap 55 from the nozzle surface 40a of the discharge head 4, and a position between the elevated position Pu and the lowered position Pd where the impregnation portion 76 is close to the nozzle surface 40a.

[0059] The operation of the switching valve 85 is controlled by the control unit 91. This allows switching between a first state in which the first waste liquid passage 81 and the third waste liquid passage 83 are in communication, and a second state in which the second waste liquid passage 82 and the third waste liquid passage 83 are in communication.

[0060] The operation of the suction pump 84 is controlled by the control unit 91. This allows the suction pump 84 to be activated and negative pressure to be generated in the first waste liquid passage 81 or the second waste liquid passage 82.

[0061] Furthermore, the memory unit 92 stores the cleaning fluid discharge position PB and the maintenance position PC of the discharge head 4.

[0062] [Example of operation] The following describes an example of maintenance operation. Figure 6 is a flowchart showing an example of maintenance operation of the liquid dispensing device 100. In the initial state shown in Figure 2, the dispensing head 4 is in the maintenance position PC and is capped by a cap 55 located in the raised position Pu. That is, the cleaning liquid dispensing nozzle row 42a and the ink dispensing nozzle row 42b are covered by the first cap portion 56a and the second cap portion 56b, respectively. The wiper 60 is in the standby position P1. The control unit 91 moves the dispensing head 4 to the maintenance position PC if it is not in the maintenance position PC. The control unit 91 also moves the cap 55 to the raised position Pu if it is not in the raised position Pu. Furthermore, the control unit 91 moves the wiper 60 to the standby position P1 if it is not in the standby position P1.

[0063] As shown in Figure 6, the control unit 91 first performs a determination process to determine whether or not it has received a purge signal (step S1). If the control unit 91 determines that it has not received a purge signal (NO in step S1), it performs step S1 again and waits until it receives a purge signal. If the control unit 91 determines that it has received a purge signal (YES in step S1), it then performs the following in order: suction purge process and wiping arrangement process (step S2), wiping process (step S3), release process (step S4), impregnation process (step S5), cleaning process (step S6), avoidance process (step S7), and return process (step S8). In this way, the control unit 91 performs maintenance operations triggered by a purge signal for performing a suction purge.

[0064] In step S2, the control unit 91 simultaneously performs the suction purging process and the wiping and placement process.

[0065] In the wiping positioning process of step S2, the control unit 91 raises the wiper 60, which is located in the standby position P1, and places it in the wiping position P2, as shown in Figure 8A. As a result, the upper end of the wiper body 61 is positioned above the passage area A.

[0066] Figure 7 is a flowchart showing an example of the operation of the suction purging process of the liquid discharge device 100. As shown in Figure 7, in the suction purging process of step S2, the control unit 91 executes the pre-cleaning process (step S21) and the purging process (step S22) in that order.

[0067] As shown in Figure 4, in the preliminary cleaning process of step S21, the control unit 91 first switches the switching valve 85 to a first state in which the first waste liquid passage 81 and the third waste liquid passage 83 are in communication. Then, the control unit 91 operates the suction pump 84. As a result, the third waste liquid passage 83 becomes negative pressure, and the first waste liquid passage 81 and the first cap section 56a, which are continuous with the third waste liquid passage 83, also become negative pressure, and cleaning liquid is drawn in from the cleaning liquid discharge nozzles 41a of the cleaning liquid discharge nozzle row 42a. The cleaning liquid drawn in from the cleaning liquid discharge nozzle row 42a passes through the first waste liquid passage 81, the switching valve 85 and the third waste liquid passage 83 and is collected in the waste liquid tank 86. Therefore, the first waste liquid passage 81, the switching valve 85 and the third waste liquid passage 83 become wet with cleaning liquid. Then, the control unit 91 stops the suction pump 84.

[0068] Next, in the purging process of step S22, the control unit 91 first switches the switching valve 85 to a second state in which the second waste liquid passage 82 and the third waste liquid passage 83 are in communication. Then, the control unit 91 operates the suction pump 84. As a result, the second waste liquid passage 82 and the second cap section 56b, which are continuous with the third waste liquid passage 83, become negative pressure, and ink is drawn in from the ink discharge nozzles 41b of the ink discharge nozzle row 42b. The ink drawn in from the ink discharge nozzles 41b passes through the second waste liquid passage 82, the switching valve 85, and the third waste liquid passage 83 and is collected in the waste liquid tank 86. As described above, since the switching valve 85 and the third waste liquid passage 83 are wet with cleaning fluid, when the ink passes through the switching valve 85 and the third waste liquid passage 83, the ink and cleaning fluid come into contact, which can reduce the viscosity of the ink. This prevents the ink from solidifying in the switching valve 85 and the third waste liquid passage 83. In particular, preventing ink solidification in the switching valve 85 prevents malfunction of the switching valve 85 due to solidified ink. The suction force of the suction pump 84 in the pre-cleaning process may be lower than the suction force of the suction pump 84 in the purging process. This is because if the suction force of the suction pump 84 in the pre-cleaning process is lower than the suction force of the suction pump 84 in the purging process, droplets of the cleaning solution are more likely to remain in the switching valve 85 and the third waste liquid passage 83, thereby increasing the amount of cleaning solution that comes into contact with the ink.

[0069] Next, in the wiping process of step S3, the control unit 91 first lowers the cap 55 to the lowered position Pd, as shown in Figure 8B. This allows the discharge head 4 to move smoothly. Next, as shown in Figure 8C, the control unit 91 moves the discharge head 4, which is located in the maintenance position PC, inward to position it on the platen 11. With the wiper body 61 positioned in the wiping position P2, the control unit 91 moves the discharge head 4 to one of the wiping positions P2 in the movement direction D2, bringing the upper end of the outer surface of the wiper body 61 into contact with the nozzle surface 40a, and the wiper body 61 wipes the ink adhering to the nozzle surface 40a. At this time, the wiper 60 receives an inward force. This inward force is received by the guide surface 54b, which is in contact with the inward-facing surface of the main body holder 62, and the guide part 53 into which the pivot shaft 66 is fitted. Therefore, the wiper 60 is restrained by the frame 50 and does not move inward.

[0070] Since the cleaning fluid discharge nozzle row 42a is located inside the ink discharge nozzle row 42b, the wiper body 61 wipes the cleaning fluid discharge nozzle row 42a and then the ink discharge nozzle row 42b in that order. Therefore, the ink adhering to the area around the ink discharge nozzle 41b on the nozzle surface 40a is pushed in the opposite direction to the direction in which the cleaning fluid discharge nozzle 41a is located. This prevents ink from adhering to the cleaning fluid discharge nozzle 41a and prevents the cleaning fluid from being contaminated with ink. When the wiper body 61 comes into contact with the nozzle surface 40a, the wiper body 61 separates from the back plate 67 and curves significantly inward, creating a gap between the wiper body 61 and the back plate 67. The ink wiped by the wiper body 61 is attracted to this gap, making it less likely for ink to remain on the wiper body 61.

[0071] Next, in the release process of step S4, the control unit 91 moves the discharge head 4, located on the platen 11, towards the maintenance area M again, as shown in Figure 8D. As a result, the discharge head 4 first passes the release position PA above the wiper 60. When the discharge head 4 reaches the release position PA, the upper end of the wiper body 61, located at the wiping position P2, comes into contact with the discharge head 4, causing the wiper body 61 to receive an outward force. The outward force received by the wiper body 61 is absorbed by the back plate 67, located on the outside of the wiper body 61. As a result, the wiper 60 rotates in the circumferential direction around the pivot axis 66, and the wiper 60 tilts outward. When the wiper 60 tilts outward, the stopper 65 disengages from the upper surface 54a of the connection part 54, and the movement restriction by the stopper 65 is released. The wiper 60 then receives the downward component of the biasing force of the elastic body 71 and moves to the lower standby position P1.

[0072] Next, in the impregnation process of step S5, as shown in Figure 8E, the control unit 91 moves the carriage 21 outward after the discharge head 4 has passed the release position PA. Then, after moving the discharge head 4 to the cleaning liquid discharge position PB facing the impregnation section 76, the control unit 91 discharges droplets of cleaning liquid from the cleaning liquid discharge nozzle 41a to the impregnation section 76 at the cleaning liquid discharge position PB. The discharged droplets land on the impregnation section 76, replenishing the impregnation section 76 with cleaning liquid. This maintains the state in which the impregnation section 76 is impregnated with cleaning liquid. Furthermore, since the impregnation process is performed during the process of moving to the maintenance position PC, the cycle time of the maintenance operation can be shortened. The control unit 91 may also stop the discharge head 4, which is moving outward, at the cleaning liquid discharge position PB. Then, the control unit 91 moves the discharge head 4 to the maintenance position PC.

[0073] Next, in the cleaning process of step S6, the control unit 91 rotates the rotating cam 72, as shown in Figures 8F and 8G, thereby pushing the lower end of the arm 64 inward by the tilting mechanism 72d. As a result, the wiper 60 moves from the standby position P1, which is the separated position, to the contact position P3.

[0074] As the wiper 60 moves from the standby position P1 towards the contact position P3, as shown in Figure 8F, the outer surface of the wiper body 61 moves outward and rubs against the cutting edge of the blade 77. This causes the ink adhering to the outer surface of the wiper body 61 to be scraped off by the cutting edge of the blade 77. The wiper body 61 deforms and passes below the blade 77. Subsequently, as shown in Figure 8G, the wiper body 61 is pressed against the impregnation section 76. When the wiper body 61 is pressed against the impregnation section 76, the ink adhering to the outer surface of the wiper body 61 comes into contact with the cleaning fluid in the impregnation section 76, its viscosity decreases, making it easier to separate from the outer surface of the wiper body 61, and also adheres to the impregnation section 76 by physical contact with it. This cleans the wiper body 61.

[0075] Next, in the avoidance process of step S7, the control unit 91 moves the cap 55 and the cleaning unit 75 from the lowered position Pd to the raised position Pu, as shown in Figure 8H. As the cleaning unit 75 moves, the impregnation unit 76 rubs against the outer surface of the wiper body 61, wiping away any ink remaining on the outer surface of the wiper body 61. Also, as the cleaning unit 75 moves, the cutting edge of the blade 77 retracts above the movement trajectory of the wiper body 61, which moves from the contact position P3 to the standby position P1 around the pivot axis 66. This prevents the wiper body 61 from getting caught on the cutting edge of the blade 77 and being hindered from moving to the standby position P1 when the wiper body 61 moves from the contact position P3 to the standby position P1.

[0076] Next, in the return process of step S7, the control unit 91 rotates the rotating cam 72 until the lower end of the arm 64 is positioned beyond the tilting mechanism 72d, as shown in Figure 8I. As a result, the force pushing the lower end of the wiper 60 inward is eliminated, and the wiper 60, receiving the inward component of the biasing force of the elastic body 71, moves from the contact position P3 to the standby position P1.

[0077] The control unit 91 also periodically positions the ejection head 4 to the maintenance position PC and performs a flushing process. The flushing process involves ejecting a small amount of ink from the ink ejection nozzle 41b to maintain the meniscus of the ink ejection nozzle 41b in a normal state.

[0078] As described above, the liquid dispensing device 100 can remove ink adhering to the wiper 60 by bringing the wiper body 61 into contact with the impregnated portion 76 which is impregnated with cleaning liquid. This allows the cleaning liquid to reduce the viscosity of the ink and remove the ink adhering to the wiper 60, even when using high-viscosity ink.

[0079] (Embodiment 2) The following describes the operation of Embodiment 2, focusing on the differences from Embodiment 1. Figure 9 is a flowchart showing an example of the operation of the liquid dispensing device 100 according to Embodiment 2.

[0080] In this embodiment, as shown in Figure 9, after the release process in step S4, the control unit 91 performs a determination process (first determination process) in step S201 to determine whether or not it is an initial introduction. Initial introduction means impregnating the impregnation part 76 with cleaning liquid for the first time. For example, cleaning liquid is discharged from the discharge head 4 to the impregnation part 76, and when the wiper body 61 touches the impregnation part 76, the cleaning liquid is applied to the wiper body 61 to the extent that it dissolves the solidified ink, while the cleaning liquid is held in the impregnation part 76 to the extent that no dripping occurs from the impregnation part 76. If the control unit 91 determines that it is not an initial introduction (NO in step S201), it performs a normal impregnation process in step S202. In the normal impregnation process in step S202, when the discharge head 4 reaches the cleaning liquid discharge position PB facing the impregnation part 76, the control unit 91 discharges a predetermined first amount of cleaning liquid from the cleaning liquid discharge nozzle 41a at the cleaning liquid discharge position PB. Then, the control unit 91 executes the processing from step S6 onward.

[0081] On the other hand, if the control unit 91 determines that it is an initial introduction (YES in step S201), it performs a large-volume impregnation process in step S203. In this way, the control unit 91 selectively performs one of the normal impregnation process and the large-volume impregnation process. In the large-volume impregnation process in step S203, when the discharge head 4 reaches the cleaning liquid discharge position PB facing the impregnation section 76, the control unit 91 discharges a second amount of cleaning liquid from the cleaning liquid discharge nozzle 41a, which is greater than the first amount, at the cleaning liquid discharge position PB. Then, the control unit 91 performs the cleaning process in step S6 and the process following the cleaning process.

[0082] In the large-volume impregnation process, when the control unit 91 discharges a second volume of cleaning solution from the cleaning solution discharge nozzle 41a, it discharges a large volume of droplets from the cleaning solution discharge nozzle 41a. In the normal impregnation process, when the control unit 91 discharges a second volume of cleaning solution from the cleaning solution discharge nozzle 41a, it discharges a medium volume or small volume of droplets from the cleaning solution discharge nozzle 41a. The process of discharging small volume of droplets from the cleaning solution discharge nozzle 41a is the first normal impregnation process, and the process of discharging medium volume of droplets from the cleaning solution discharge nozzle 41a is the second normal impregnation process.

[0083] The control unit 91 may use a superimposed waveform to discharge droplets from the washing liquid discharge nozzle row 42a during the large-volume impregnation process. The superimposed waveform is a drive waveform that drives the drive element of the discharge head drive unit 45, and is a drive waveform that repeats rising and falling at each Acoustic Length corresponding to the acoustic resonance period. By using a superimposed waveform, the amount of droplets discharged from the washing liquid discharge nozzle 41a can be increased.

[0084] Furthermore, in the large-volume impregnation process, the control unit 91 may use the lifting mechanism 59 to position the impregnation section 76 at a position between the raised position Pu and the lowered position Pd, and close to the nozzle surface 40a. This suppresses the scattering and adhesion of cleaning solution mist to the surroundings.

[0085] (Embodiment 3) The operation of Embodiment 3 will be described below, focusing on the differences from Embodiment 1. Figure 10 is a flowchart showing an example of the operation of the liquid dispensing device 100 according to Embodiment 3.

[0086] In this embodiment, as shown in Figure 10, the control unit 91 performs a determination process (fourth determination process) in step S301 to determine whether the elapsed time since the previous impregnation process has been executed is equal to or greater than a predetermined time T, after the release process in step S4. Time T is longer than the waiting time between the first and second flushing processes in two consecutive flushing processes. In two consecutive flushing processes, no other flushing processes are performed between the first and second flushing processes.

[0087] Furthermore, the control unit 91 corrects time T based on the ambient temperature measured by the temperature measurement unit 16. In addition, the control unit 91 corrects time T based on the ambient humidity measured by the humidity measurement unit 17. Figure 11 is a graph showing the correlation between ambient temperature and humidity and time T. The control unit 91 corrects time T using the correlation shown in Figure 11.

[0088] Then, if the control unit 91 determines that time T is less than (NO in step S301), it will not perform the impregnation treatment in step S5, but will instead perform the washing treatment in step S6 and the subsequent treatments following the washing treatment.

[0089] On the other hand, if the control unit 91 determines that the time is T or longer (YES in step S301), it executes the impregnation process in step S5. After executing the impregnation process in step S5, the control unit 91 executes the washing process in step S6 and the process following the washing process.

[0090] Thus, in this embodiment, the control unit 91 determines whether or not to perform the impregnation treatment based on the elapsed time since the previous impregnation treatment was performed, which reduces the amount of cleaning solution used.

[0091] (Embodiment 4) The following describes the operation of Embodiment 4, focusing on the differences from Embodiment 1. Figure 12 is a flowchart showing an example of the operation of the liquid dispensing device 100 according to Embodiment 4.

[0092] In this embodiment, as shown in Figure 12, after the release process in step S4, the control unit 91 performs a determination process in step S401 to determine whether the number of times the wiping process has been performed since the previous impregnation process is N or more. N is a preset natural number.

[0093] Then, if the control unit 91 determines that the number of times the wiping process has been performed since the previous impregnation process is N or more (YES in step S401), it performs the impregnation process in step S5. After performing the impregnation process in step S5, the control unit 91 performs the cleaning process in step S6 and the processes following the cleaning process.

[0094] On the other hand, if the control unit 91 determines that the number of times the wiping process has been performed since the previous impregnation process is less than N (NO in step S401), it further performs a determination process to determine whether the elapsed time since the previous impregnation process is greater than or equal to a predetermined time T (step S402). Time T is the same value as in Embodiment 3.

[0095] Then, if the control unit 91 determines that the elapsed time since the previous impregnation treatment is greater than or equal to a predetermined time T (YES in step S402), it executes the impregnation treatment in step S5. After executing the impregnation treatment in step S5, the control unit 91 executes the cleaning treatment in step S6 and the treatment following the cleaning treatment.

[0096] On the other hand, if the control unit 91 determines that the elapsed time since the previous impregnation treatment is not equal to or greater than a predetermined time T (NO in step S402), it will not perform the impregnation treatment in step S5, but will instead perform the cleaning treatment in step S6 and the treatment following the cleaning treatment.

[0097] Thus, in this embodiment, the control unit 91 performs a determination process to determine whether or not to perform the impregnation treatment again, based on the number of times the wiping treatment has been performed since the previous impregnation treatment and the time elapsed since the previous impregnation treatment. This makes it possible to further reduce the amount of cleaning solution used.

[0098] (Embodiment 5) The operation of Embodiment 5 will be described below, focusing on the differences from Embodiment 1. Figure 13 is a flowchart showing an example of the operation of the liquid dispensing device 100 according to Embodiment 5.

[0099] In this embodiment, as shown in Figure 13, the control unit 91, after the release process in step S4, executes a determination process (third determination process) in step S501 to determine whether the number of times the wiping process has been executed since the previous normal impregnation process is N or more (step S501). N is a preset natural number.

[0100] Then, if the control unit 91 determines that the number of times the wiping process has been performed since the previous normal impregnation process is N or more (YES in step S501), it further performs a determination process (second determination process) to determine whether the number of times the wiping process has been performed since the previous large-volume impregnation process is M or more (step S502). M is a preset natural number of 2 or more, and is greater than N.

[0101] Then, if the control unit 91 determines that the number of times the wiping process has been performed since the previous large-volume impregnation process is not M or more (NO in step S502), it performs the normal impregnation process in step S503. The normal impregnation process is the same as the normal impregnation process in Embodiment 2. Then, the control unit 91 performs the cleaning process in step S6 and the processes following the cleaning process.

[0102] On the other hand, if the control unit 91 determines that the number of times the wiping process has been performed since the previous large-volume impregnation process is M or more (YES in step S502), it performs the large-volume impregnation process in step S504. The large-volume impregnation process is the same as the large-volume impregnation process in Embodiment 2. Then, the control unit 91 performs the washing process in step S6 and the processes following the washing process.

[0103] Furthermore, if the control unit 91 determines in step S501 that the number of times the wiping process has been performed since the previous normal impregnation process is less than N (NO in step S501), it then performs a determination process to determine whether the elapsed time since the previous impregnation process is greater than or equal to a predetermined time T (step S505). Time T is the same value as in Embodiment 3.

[0104] Then, if the control unit 91 determines that the elapsed time since the previous impregnation treatment is greater than or equal to a predetermined time T (YES in step S505), it executes the normal impregnation treatment in step S503. Then, the control unit 91 executes the cleaning treatment in step S6 and the treatment following the cleaning treatment.

[0105] On the other hand, if the control unit 91 determines that the elapsed time since the previous impregnation treatment is less than a predetermined time T (NO in step S505), it executes the cleaning treatment in step S6 and the treatment following the cleaning treatment.

[0106] (Embodiment 6) The following describes the operation of Embodiment 6, focusing on the differences from Embodiment 1. Figure 14 is a flowchart showing an example of the operation of the liquid dispensing device 100 according to Embodiment 6.

[0107] In this embodiment, as shown in Figure 14, the control unit 91 performs a determination process to determine whether the elapsed time since the previous impregnation treatment has been performed is equal to or greater than a predetermined time T (step S601).

[0108] Then, if the control unit 91 determines that the elapsed time since the previous impregnation treatment is less than a predetermined time T (NO in step S601), it executes step S601 again and waits until the elapsed time since the previous impregnation treatment is equal to or greater than the predetermined time T. Then, if the control unit 91 determines that the elapsed time since the previous impregnation treatment is equal to or greater than the predetermined time T (YES in step S601), it executes the impregnation treatment (step S5). In this way, the control unit 91 executes the impregnation treatment in step S5 triggered by the elapsed time since the previous impregnation treatment.

[0109] (Embodiment 7) The following describes the operation of Embodiment 7, focusing on the differences from Embodiment 6. Figure 15 is a flowchart showing an example of the operation of the liquid dispensing device 100 according to Embodiment 7.

[0110] In this embodiment, the control unit 91 performs a determination process to determine whether or not print data has been received, as shown in Figure 15 (step S701).

[0111] Then, if the control unit 91 determines that it has not received print data (NO in step S701), it executes step S701 again and waits until it receives print data. Then, if the control unit 91 determines that it has received print data (YES in step S701), it executes the determination process in step S601 and the impregnation process in step S5 in order. In this way, the control unit 91 executes the impregnation process in step S5 triggered by the reception of print data and the elapsed time since the previous execution of the impregnation process.

[0112] (Embodiment 8) The following describes the operation of Embodiment 8, focusing on the differences from Embodiment 6. Figure 16 is a flowchart showing an example of the operation of the liquid dispensing device 100 according to Embodiment 8.

[0113] In this embodiment, the control unit 91 performs a determination process to determine whether or not the discharge head 4 has moved to the maintenance position PC, as shown in Figure 16 (step S801).

[0114] Then, if the control unit 91 determines that the discharge head 4 has not moved to the maintenance position PC (NO in step S801), it executes step S801 again and waits until the discharge head 4 moves to the maintenance position PC. Then, if the control unit 91 determines that the discharge head 4 has moved to the maintenance position PC (YES in step S801), it executes the determination process in S601 and the impregnation process in step S5 in order. In this way, the control unit 91 executes the impregnation process in step S5 triggered by the movement of the discharge head 4 to the maintenance position PC and the elapsed time since the previous execution of the impregnation process.

[0115] From the above description, many improvements and other embodiments of the present invention will be apparent to those skilled in the art. Therefore, the above description should be interpreted as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of its structure and / or function can be substantially modified without departing from the spirit of the invention. [Explanation of Symbols]

[0116] P1 Standby position (separated position) P2 Wiping position P3 Contact position PA release position PB cleaning solution dispensing position PC maintenance location 2. Head movement mechanism 4 Discharge heads 5. Maintenance Department 9. Controller 11 Platen 21 Carriage 22 Carriage drive unit 40 Nozzle Plates 40a Nozzle surface 41 nozzles 41a Cleaning fluid discharge nozzle 41b Ink ejection nozzle 42 nozzle rows 42a Washing fluid discharge nozzle row 42b Ink ejection nozzle row 45 Discharge head drive unit 53 Information Department 54 Connection part 55 caps 56 Cap body 57 Cap holder 59 Lifting mechanism 60 wipers 61 Wiper body 62 Wiper support mechanism 70 Wiper movement mechanism 75 Cleaning section 76 Impregnation section 100 Liquid dispensing device

Claims

1. A discharge head having a nozzle plate with a first nozzle opening for discharging droplets of cleaning solution and a second nozzle opening for discharging droplets of a predetermined liquid different from the cleaning solution, A discharge head drive unit that discharges the droplets from the first nozzle and the second nozzle, A head movement mechanism for moving the discharge head in the direction of movement, An impregnation portion is positioned opposite to the passage region, which is the region through which the nozzle surface of the nozzle plate passes as the discharge head moves, and is impregnated with the cleaning liquid, A wiper having a wiper body for wiping the nozzle surface and a body holder for supporting the wiper body, A wiper moving mechanism moves the wiper body between a position where the wiper body is separated from the impregnation portion and a position where the wiper body is in contact with the impregnation portion. Equipped with a controller, The controller is, After moving the discharge head to a predetermined cleaning liquid discharge position facing the impregnation portion in the passage region, an impregnation process is performed in which droplets of the cleaning liquid are discharged from the first nozzle to the impregnation portion at the predetermined cleaning liquid discharge position. A liquid dispensing device that, after performing the impregnation treatment, performs a cleaning treatment in which the wiper body is moved from the separated position to the contact position to clean the wiper body.

2. The nozzle plate is fitted with a cap that contacts the nozzle and covers it, The wiper moving mechanism moves the wiper body between a wiping position in which the wiper body is positioned within the passage area and a waiting position in which the wiper body is waiting outside the passage area. The wiping position is located above the standby position. The main body holder has a stopper that allows the wiper body to move from the standby position to the wiping position and restricts its movement from the wiping position to the standby position. The controller is, A wiping process in which, with the wiper body positioned at the wiping position, the discharge head is moved to one of the wiping positions in the direction of movement, and the nozzle surface is wiped by the wiper body. The movement restriction by the aforementioned tooth stopper is released when the discharge head, moving in the other direction of movement, comes into contact with the wiper body located in the wiping position at a predetermined release position. The liquid dispensing device according to claim 1, wherein in the passage region, the release position, the cleaning liquid discharge position, and the maintenance position where the cap faces each other are arranged in a line from one direction of movement to the other.

3. The impregnation treatment includes a normal impregnation treatment in which a predetermined first amount of the cleaning liquid is discharged from the first nozzle at the cleaning liquid discharge position, and a large-volume impregnation treatment in which a second amount greater than the first amount of the cleaning liquid is discharged from the first nozzle at the cleaning liquid discharge position. The liquid dispensing apparatus according to claim 1, wherein the controller selectively performs one of the normal impregnation treatment and the large-volume impregnation treatment in the impregnation treatment.

4. The controller is, A first determination process to determine whether or not this is the initial introduction in which the impregnation portion is impregnated with the cleaning solution for the first time, The liquid dispensing device according to claim 3, which, when it is determined that it is the initial introduction, performs the large-volume impregnation treatment.

5. The wiper moving mechanism moves the wiper body between a wiping position in which the wiper body is positioned within the passage area and a waiting position in which the wiper body is waiting outside the passage area. The controller is, A wiping process in which, with the wiper body positioned at the wiping position, the discharge head is moved to one of the wiping positions in the direction of movement, and the nozzle surface is wiped by the wiper; A second determination process is performed to determine whether the number of times the wiping process is executed is M or more, which is a natural number of 2 or more. The liquid dispensing device according to claim 3, which performs the large-volume impregnation treatment when it is determined that the number of times the wiping treatment is performed is M or more, which is a natural number of 2 or more.

6. The controller is, The discharge head drive unit selectively discharges one of the following droplets from the first nozzle: a small volume droplet, a medium volume droplet, and a large volume droplet. The conventional impregnation treatment includes a first conventional impregnation treatment that discharges small-volume droplets and a second conventional impregnation treatment that discharges medium-volume droplets. A third determination process that determines whether the number of times the wiping process is performed is N or more, which is a natural number less than M, The liquid dispensing device according to claim 5, which performs the first normal impregnation treatment or the second normal impregnation treatment when it is determined that the number of times the wiping treatment is performed is N or more, which is a natural number less than M.

7. The controller is, A fourth determination process to determine whether the elapsed time since the previous impregnation treatment has been performed is equal to or greater than a predetermined time T, The liquid dispensing device according to claim 1, which performs the impregnation treatment when it is determined that the elapsed time since the previous execution of the impregnation treatment is equal to or greater than a predetermined time T.

8. The controller performs a flushing process to discharge the predetermined liquid from the second nozzle. The liquid dispensing apparatus according to claim 7, wherein the time T is longer than the waiting time between the first flushing process and the second flushing process in two consecutive flushing processes.

9. It has a temperature measuring unit that measures the ambient temperature, The liquid dispensing apparatus according to claim 7, wherein the controller corrects the time T based on the ambient temperature measured by the temperature measuring unit.

10. It has a humidity measuring unit that measures the humidity of the environment, The liquid dispensing apparatus according to claim 7, wherein the controller corrects the time T based on the humidity of the environment measured by the humidity measuring unit.

11. The liquid dispensing device according to claim 7, wherein the first nozzle and the second nozzle are arranged in the order of the first nozzle and the second nozzle from one direction of movement to the other.

12. A cap having a first cap portion that abuts against the discharge head and covers the first nozzle, and a second cap portion that abuts against the discharge head and covers the second nozzle, The upstream end is connected to the first cap portion, and the first wastewater channel through which the cleaning liquid flows downstream, The upstream end is connected to the second cap portion, and the second wastewater channel through which the cleaning liquid flows downstream, Waste liquid tank and A third wastewater channel whose downstream end is connected to the wastewater tank, A suction pump is placed in the third wastewater passage and, upon operation, generates negative pressure in the first wastewater passage or the second wastewater passage. The system includes a switching valve that switches between a first state in which the first wastewater passage and the third wastewater passage are in communication, and a second state in which the second wastewater passage and the third wastewater passage are in communication. The controller is, The suction pump is activated and the switching valve is switched to the first state or the second state. The liquid discharge device according to claim 1, comprising: a pre-cleaning process in which the suction pump is operated with the switching valve in a first state; and a purging process in which the suction pump is operated with the switching valve in a second state after the pre-cleaning process has been performed.

13. The aforementioned liquid contains solid components. The solid component includes resin fine particles and solid components of colorant. The resin fine particles are contained in the predetermined liquid in an amount of 0.1 wt% to 30 wt%, The solid content of the colorant is contained in the predetermined liquid in the range of 0.1 wt% to 20 wt%, The liquid dispensing device according to claim 1, wherein the cleaning solution does not contain the solid components.

14. A discharge head having a nozzle plate with a first nozzle opening for discharging droplets of cleaning solution and a second nozzle opening for discharging droplets of a predetermined liquid different from the cleaning solution, A discharge head drive unit that discharges the droplets from the first nozzle and the second nozzle, A head movement mechanism for moving the discharge head in the direction of movement, An impregnation portion is positioned opposite to the passage region, which is the region through which the nozzle surface of the nozzle plate passes as the discharge head moves, and is impregnated with the cleaning liquid, A wiper having a wiper body for wiping the nozzle surface and a body holder for supporting the wiper body, A wiper moving mechanism moves the wiper body between a position where the wiper body is separated from the impregnation portion and a position where the wiper body is in contact with the impregnation portion. A control program for a liquid dispensing device comprising a controller, The controller is, After moving the discharge head to a predetermined cleaning liquid discharge position facing the impregnation portion in the passage region, an impregnation process is performed in which droplets of the cleaning liquid are discharged from the first nozzle to the impregnation portion at the predetermined cleaning liquid discharge position. A control program that, after performing the impregnation treatment, causes the wiper body to be moved from the separated position to the contact position and cleaned.

15. A discharge head having a nozzle plate with a first nozzle opening for discharging droplets of cleaning solution and a second nozzle opening for discharging droplets of a predetermined liquid different from the cleaning solution, A discharge head drive unit that discharges the droplets from the first nozzle and the second nozzle, A head movement mechanism for moving the discharge head in the direction of movement, An impregnation portion is positioned opposite to the passage region, which is the region through which the nozzle surface of the nozzle plate passes as the discharge head moves, and is impregnated with the cleaning liquid, A wiper having a wiper body for wiping the nozzle surface and a body holder for supporting the wiper body, A wiper cleaning method for a liquid discharge device, comprising a wiper moving mechanism that moves the wiper body between a separated position away from the impregnation portion and a contact position where the wiper body contacts the impregnation portion, After moving the discharge head to a predetermined cleaning liquid discharge position facing the impregnation portion in the passage region, droplets of the cleaning liquid are discharged from the first nozzle to the impregnation portion at the predetermined cleaning liquid discharge position. A wiper cleaning method comprising moving the wiper body from the separated position to the contact position to clean the wiper body.

Images