Printer

Abstract

To suppress time lags in switching between application of pressure and reduction of pressure of an ink flow passage.SOLUTION: A printer comprises: an ink container 61 storing ink; an ink head 41 that discharges ink; an ink flow passage 81 including a first flow passage 81b and a second flow passage 81c, through which the ink container 61 is connected to the ink head 41; a liquid feeding pump 83, provided on the first flow passage 81b, which feeds ink in a direction from the ink container 61 toward the ink head 41; and a pressure reduction pump 84, provided on the second flow passage 81c, which feeds ink in a direction from the ink head 41 toward the ink container 61.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a printer.

Background Art

[0002] There has conventionally been known a printer including an ink head in which nozzles for discharging ink are formed, and an ink flow path for supplying ink to the ink head, and the ink in the ink flow path is pressurized to cause the ink to leak from the nozzles to clean the nozzles. For example, Patent Document 1 discloses an inkjet recording apparatus including a recording head and an ink supply mechanism for supplying ink to the recording head. In the inkjet recording apparatus described in Patent Document 1, the ink supply mechanism includes a tank portion in which ink is stored and a pump portion for applying a positive pressure or a negative pressure to the ink. The pump portion is configured to change the direction of the pressure by changing the rotation direction of the drive motor. The inkjet recording apparatus described in Patent Document 1 drives the pump portion forward to apply a positive pressure to the ink and causes the ink to leak from the ink discharge surface of the recording head. Further, the inkjet recording apparatus described in Patent Document 1 is configured to drive the pump portion in reverse to apply a negative pressure to the ink and stop the leakage of the ink from the ink discharge surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a configuration where the pump section of an ink supply mechanism is rotated in the reverse direction when reducing the pressure of ink, as in the inkjet recording apparatus described in Patent Document 1, a time lag occurs when switching the rotation direction of the pump section from normal rotation to reverse rotation. When discharging ink under pressure, ink accumulates on the surface of the nozzles, and the ink accumulated in adjacent nozzles gathers. When the pump is stopped after pressurization, due to the time lag, while the pump is stopped, due to the pressure difference between the nozzles, the ink that has gathered and become mixed is drawn into the nozzle with a lower internal pressure. In this case, ink mixing in printing occurs over a long period or at unexpected timings.

[0005] The present invention has been made in view of such a point, and an object thereof is to provide a printer in which a time lag is less likely to occur when switching between pressurization and depressurization of an ink flow path.

Means for Solving the Problems

[0006] The printer disclosed herein includes an ink container in which ink is stored, an ink head from which ink is discharged, a first flow path and a second flow path, an ink flow path connecting the ink container and the ink head, a liquid feed pump provided in the first flow path for sending ink in a direction from the ink container toward the ink head, and a pressure reducing pump provided in the second flow path for sending ink in a direction from the ink head toward the ink container.

[0007] According to the above printer, the inside of the ink flow path can be pressurized by driving the liquid feed pump, and the inside of the ink flow path can be depressurized by driving the pressure reducing pump. Since the liquid feed pump and the pressure reducing pump are separate pumps, it is possible to suppress the time lag between pressurization and depressurization.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

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Figure 13

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the embodiments described here are not intended to limit the present invention in particular. In addition, members and parts having the same function are denoted by the same reference numerals, and overlapping explanations are omitted or simplified as appropriate.

[0010] [First Embodiment] [Configuration of Inkjet Printer] FIG. 1 is a perspective view showing an inkjet printer 10 (hereinafter simply referred to as printer 10) according to an embodiment. In the following description, unless otherwise specified, when the printer 10 is viewed from the front, the direction away from the printer 10 is defined as the front, and the direction approaching the printer 10 is defined as the rear. Left, right, up, and down respectively mean left, right, up, and down when the printer 10 is viewed from the front. Also, in the drawings, the reference signs F, Rr, L, R, U, and D respectively mean front, rear, left, right, up, and down. However, the above directions are merely defined for the convenience of explanation and do not limit the installation mode of the printer 10 in any way, nor do they limit the present invention in any way.

[0011] In this embodiment, the printer 10 is an inkjet printer. In this embodiment, the "inkjet method" refers to an inkjet type by various conventionally known methods including various continuous methods such as a binary deflection method or a continuous deflection method, and various on-demand methods such as a thermal method or a piezoelectric element method.

[0012] As shown in FIG. 1, the printer 10 is formed in a box shape. In this embodiment, the printer 10 includes a case 11 and a front cover 12. FIG. 2 is a front view showing the printer 10 with the front cover 12 opened. As shown in FIG. 2, an opening is formed in the front portion of the case 11. The front cover 12 is provided so as to be able to open and close the opening of the case 11. Here, the front cover 12 is supported by the case 11 so as to be rotatable about the rear end. A window portion 12a is provided in the front cover 12. The window portion 12a is formed of, for example, a transparent acrylic plate. The user can visually recognize the internal space of the case 11 through the window portion 12a.

[0013] As shown in FIG. 2, inside the internal space of the printer 10, there are provided a flatbed 20, a bed moving device 25, a carriage 30, a carriage moving device 35, a recording head 40, a light irradiation device 50, an ink cartridge accommodating portion 60, a capping device 70, and a control device 100 (see FIG. 1). The printer 10 includes an ink supply system 80 that supplies the ink in the ink cartridge 61 accommodated in the ink cartridge accommodating portion 60 to the recording head 40.

[0014] The flatbed 20 is a support base that supports the recording medium 5. The printer 10 according to the present embodiment is a so-called flatbed type printer. The flatbed 20 is a flat plate-shaped member. The shape of the recording medium 5 is not particularly limited, and in addition to a flat plate shape, it may have various three-dimensional shapes. Also, the material of the recording medium 5 is not particularly limited, and the recording medium 5 may be, for example, wood, metal, glass, paper, cloth, or the like. The flatbed 20 is disposed substantially at the center in the left-right direction within the internal space of the case 11.

[0015] Below the flatbed 20, the bed moving device 25 is disposed. The bed moving device 25 moves the flatbed 20 in the front-rear direction and the up-down direction. The flatbed 20 is supported from below by the bed moving device 25. The bed moving device 25 includes a front-rear direction moving device 26 and an up-down direction moving device 27. The up-down direction moving device 27 supports the flatbed 20 and moves it in the up-down direction. The up-down direction moving device 27 is supported from below by the front-rear direction moving device 26. The front-rear direction moving device 26 supports the up-down direction moving device 27 and moves it in the front-rear direction. However, the configuration of the bed moving device 25 is not limited. For example, the front-rear direction moving device 26 and the up-down direction moving device 27 may have the reverse vertical positional relationship.

[0016] The carriage 30 mounts a recording head 40 and a light irradiation device 50. The carriage 30 is provided above the flatbed 20. The carriage 30 is moved in the left - right direction by a carriage moving device 35. The carriage moving device 35 includes a guide rail 36, a belt 37, left and right pulleys (not shown), and a carriage motor 38 (see FIG. 5).

[0017] As shown in FIG. 2, the guide rail 36 extends in the left - right direction. The carriage 30 is slidably engaged with the guide rail 36. An endless belt 37 is fixed to the carriage 30. The belt 37 is wound around pulleys (not shown) provided on the right side and the left side of the guide rail 36. A carriage motor 38 is attached to one of the pulleys. When the carriage motor 38 is driven, the pulley rotates and the belt 37 runs. Thereby, the carriage 30 moves in the left - right direction along the guide rail 36.

[0018] As shown in FIG. 2, the recording head 40 is provided on the lower surface of the carriage 30. The recording head 40 is provided above the flatbed 20. The recording head 40 includes a plurality of ink heads 41. The plurality of ink heads 41 each discharge ink. The plurality of ink heads 41 are arranged side by side in the left - right direction. Although not shown, the plurality of ink heads 41 all extend in the front - rear direction. The plurality of ink heads 41 each have a plurality of nozzles 42 (see FIG. 3) from which ink is discharged. The lower surfaces of the plurality of ink heads 41 constitute a nozzle surface on which the plurality of nozzles 42 are formed.

[0019] In this embodiment, the ink discharged from the nozzles 42 of the recording head 40 is a photocurable ink. Here, the photocurable ink is an ultraviolet - curable ink that cures when irradiated with ultraviolet rays. However, the components, properties, etc. of the ink are not particularly limited. The ink may be, for example, a heat - curable ink.

[0020] The light irradiation device 50 is provided to the left of the recording head 40. The light irradiation device 50 irradiates light for curing the photocurable ink toward the flat bed 20. The light irradiation device 50 has, for example, a light source (not shown) composed of a plurality of ultraviolet irradiation LEDs. The light irradiation device 50 is provided with an irradiation port (not shown) that opens downward and transmits the light generated by the light source.

[0021] The ink cartridge accommodating portion 60 is configured to be able to accommodate a plurality of ink cartridges 61. The ink cartridge 61 is an example of an ink container in which ink is accommodated. A pouch in which ink is stored is housed in the ink cartridge 61. The ink cartridge 61 is detachably attached to the ink cartridge accommodating portion 60. However, the ink container is not limited to the ink cartridge 61, and may be, for example, a container in which ink poured from a pouch, a bottle, or the like is stored.

[0022] The capping device 70 includes a plurality of caps 71, a cap moving device 72, and a plurality of suction pumps 73. FIG. 3 is a schematic diagram showing the configuration of the ink supply system 80 and the capping device 70. As shown in FIG. 3, the cap 71 and the suction pump 73 are provided one by one with respect to the ink head 41. The number of cap moving devices 72 is one here. The cap 71 is configured to be attachable to the ink head 41. The cap 71 has a container-like shape with an open upper surface. The cap 71 is formed of rubber or the like. When attached to the ink head 41, the upper edge of the cap 71 is in close contact with the nozzle surface of the ink head 41. The cap 71 is attached to the ink head 41 to protect the ink head 41 and prevent its drying. As will be described later, the ink in the ink head 41 is discharged to the cap 71 in a timely manner.

[0023] The plurality of caps 71 are supported by a cap moving device 72. The cap moving device 72 attaches or separates the plurality of caps 71 from the nozzle surface of the ink head 41. The cap moving device 72 supports the plurality of caps 71 from below and moves them in the vertical direction. Thereby, the cap 71 is attached to and separated from the ink head 41. The cap moving device 72 includes, for example, a drive motor (not shown). In the present embodiment, the cap moving device 72 moves the cap 71 in the vertical direction to attach it to the ink head 41, but it may be configured to attach it by sliding obliquely, for example.

[0024] As shown in FIG. 1, a suction pump 73 is connected to the cap 71. The suction pump 73 sucks the ink discharged into the cap 71. The suction pump 73 is, for example, a vacuum pump.

[0025] An ink supply system 80 supplies the ink stored in the ink cartridge 61 to the recording head 40. As shown in FIG. 3, one system of the ink supply system 80 is provided for one ink cartridge 61. In the present embodiment, a plurality of systems of the ink supply system 80 are connected to one ink head 41. However, one system of the ink supply system 80 may be connected to one ink head 41.

[0026] As shown in FIG. 3, each ink supply system 80 includes an ink flow path 81, a valve 82, a liquid feed pump 83, a decompression pump 84, and a damper 85 (however, only the configuration of one ink supply system 80 is illustrated in FIG. 3). The ink flow path 81 connects the ink cartridge 61 and the ink head 41 and communicates the ink cartridge 61 with a plurality of nozzles 42. The valve 82 is provided in the ink flow path 81 and opens or closes the ink flow path 81. The liquid feed pump 83 is provided in the ink flow path 81 and sends ink in the direction from the ink cartridge 61 toward the ink head 41. The decompression pump 84 is provided in the ink flow path 81 and sends ink in the direction from the ink head 41 toward the ink cartridge 61. The decompression pump 84 is a pump that returns ink toward the ink cartridge 61. The damper 85 is an example of an intermediate container that alleviates pressure fluctuations of the ink by storing the ink.

[0027] As shown in FIG. 3, the ink flow path 81 includes an upstream common flow path 81a, a first flow path 81b and a second flow path 81c that branch from the upstream common flow path 81a, and a downstream common flow path 81d where the first flow path 81b and the second flow path 81c merge. The ink flow path 81 includes a first branch portion 81e that branches the upstream common flow path 81a into the first flow path 81b and the second flow path 81c, and a second branch portion 81f that merges the first flow path 81b and the second flow path 81c into the downstream common flow path 81d. In the present embodiment, the upstream common flow path 81a, the first flow path 81b, the second flow path 81c, and the downstream common flow path 81d are configured by flexible tubes. However, these flow paths are not limited to tubes and may be configured by, for example, shaped pipes.

[0028] As shown in FIG. 3, the upstream end of the upstream common flow path 81a is connected to the ink cartridge 61. The downstream end of the upstream common flow path 81a is connected to the first branch portion 81e. A valve 82 is provided in the upstream common flow path 81a. The upstream ends of the first flow path 81b and the second flow path 81c are connected to the first branch portion 81e. Here, the first branch portion 81e is composed of a tube joint that branches in three directions. A liquid feed pump 83 is provided in the first flow path 81b. A pressure reducing pump 84 is provided in the second flow path 81c.

[0029] The downstream ends of the first flow path 81b and the second flow path 81c are connected to the second branch portion 81f. Also, the upstream end of the downstream common flow path 81d is connected to the second branch portion 81f. The second branch portion 81f is also composed of a tube joint that branches in three directions. The downstream end of the downstream common flow path 81d is connected to the damper 85. The downstream common flow path 81d communicates with the ink head 41 via the damper 85.

[0030] The liquid feed pump 83 is a pump capable of opening / closing the flow path and driving / stopping. In the present embodiment, the liquid feed pump 83 is a tube pump. FIG. 4 is a schematic cross-sectional view of the liquid feed pump 83. As shown in FIG. 4, the liquid feed pump 83 includes an internal flow path 83a, a pair of rollers 83b, an arm 83c, a motor 83d, and a roller retracting mechanism 83e.

[0031] The internal flow path 83a is composed of a flexible tube. The internal flow path 83a is a member through which ink passes. Both ends of the internal flow path 83a are connected to the first flow path 81b. The liquid feed pump 83 sends out ink by squeezing the internal flow path 83a with a pair of rollers 83b. As shown in FIG. 4, the pair of rollers 83b are arranged at both ends of the arm 83c, respectively. The motor 83d rotates the arm 83c so that the pair of rollers 83b move along the arc-shaped portion of the internal flow path 83a. Thereby, the pair of rollers 83b squeeze the internal flow path 83a.

[0032] The roller retraction mechanism 83e is configured to be able to separate a pair of rollers 83b from the internal flow path 83a. The roller retraction mechanism 83e is configured to separate a pair of rollers 83b from the internal flow path 83a when the motor 83d rotates in the reverse direction. As shown in FIG. 4, in the present embodiment, the roller retraction mechanism 83e includes a pair of rubber plates 83e1 and 83e2. When the motor 83d rotates in the reverse direction, the roller 83b is moved to a position separated from the internal flow path 83a by the rubber plates 83e1 and 83e2. Thereby, the liquid feeding pump 83 is opened. When the motor 83d rotates in the forward direction from the state where the liquid feeding pump 83 is opened, the roller 83b is moved to a position where it crushes the internal flow path 83a by the rubber plates 83e1 and 83e2. Thereby, the liquid feeding pump 83 is closed. When the motor 83d rotates in the forward direction with the liquid feeding pump 83 closed, the ink is sent. In the present embodiment, the liquid feeding pump 83 is configured not to be able to send ink in the reverse direction.

[0033] The liquid feeding pump 83 is configured to be able to open, close, and send ink through the internal flow path 83a. "Stopping the liquid feeding pump 83" means not driving the motor 83d after closing the internal flow path 83a, and here it is the same as closing the internal flow path 83a.

[0034] In the present embodiment, the decompression pump 84 is also configured in the same manner as the liquid feeding pump 83. The decompression pump 84 is also configured to be able to open / close the flow path and drive / stop. However, the liquid feeding pump 83 and the decompression pump 84 are not limited to tube pumps. The liquid feeding pump 83 and the decompression pump 84 may have different configurations.

[0035] The damper 85 communicates with the ink head 41. The damper 85 is configured to store ink. As shown in FIG. 3, the damper 85 includes a main body 85a, a damper film 85b, and a detection unit 85c. When the amount of ink in the space partitioned by the main body 85a and the damper film 85b increases and the damper film 85b expands outward by more than a predetermined amount, the detection unit 85c detects this. When the detection unit 85c detects that the expansion of the damper film 85b has reached or exceeded a predetermined amount, the ink supply system 80 stops the liquid feed pump 83. When the detection unit 85c detects that the expansion of the damper film 85b has become less than a predetermined amount due to the consumption of ink, the ink supply system 80 drives the liquid feed pump 83. The ink supply system 80 supplies ink to the ink head 41 while repeatedly driving and stopping the liquid feed pump 83. The pressure in the ink flow path 81 is maintained at a negative pressure such that an ink meniscus is formed at the nozzle 42 under normal conditions.

[0036] FIG. 5 is a block diagram of the printer 10. As shown in FIG. 5, the control device 100 is electrically connected to the front-rear direction moving device 26 and the vertical direction moving device 27 of the bed moving device 25, the carriage motor 38 of the carriage moving device 35, a plurality of ink heads 41 (only one is shown in FIG. 5), the light irradiation device 50, the cap moving device 72 of the capping device 70 and a plurality of suction pumps 73 (only one is shown in FIG. 5), and the valve 82, the liquid feed pump 83, and the decompression pump 84 (only one of each is shown in FIG. 5) of the ink supply system 80, and controls their operations. Further, the control device 100 is electrically connected to the detection unit 85c of the damper 85 (only one is shown in FIG. 5) and receives a signal transmitted by the detection unit 85c. The control device 100 is, for example, a microcomputer and may include a central processing unit (hereinafter referred to as CPU), a ROM that stores programs executed by the CPU, a RAM, and the like. Each part of the control device 100 may be configured by software or by hardware. Also, each part may be a processor or a circuit. The configuration of the control device 100 is not particularly limited.

[0037] As shown in FIG. 5, the control device 100 includes a supply control unit 110, a purge control unit 120, and a stirring control unit 130 as control units for controlling the ink supply system 80. Note that the control device 100 may include other control units such as a control unit for controlling a printing operation, etc., but the description and illustration thereof are omitted here.

[0038] The supply control unit 110 controls the operation of supplying ink to the ink head 41. When ink is consumed by printing or the like, the supply control unit 110 supplies ink to the ink head 41 via the damper 85. Specifically, when the detection unit 85c detects that the ink has been consumed and the expansion of the damper film 85b has become less than a predetermined amount, the supply control unit 110 drives the liquid feed pump 83. When the detection unit 85c detects that ink has been supplied to the damper 85 and the expansion of the damper film 85b has become equal to or more than a predetermined amount, the supply control unit 110 stops the liquid feed pump 83.

[0039] As shown in FIG. 5, the purge control unit 120 includes a first pressurization control unit 121 and a first depressurization control unit 122. The first pressurization control unit 121 closes the decompression pump 84 and drives the liquid feed pump 83 to pressurize the inside of the ink flow path 81 to a pressure at which ink leaks from the ink head 41. By such pressurization, old ink is pushed out from the nozzles 42 and the ink head 41 is cleaned. The first depressurization control unit 122 closes the liquid feed pump 83 and drives the decompression pump 84 to depressurize the inside of the ink flow path 81. Thereby, the pressure inside the ink flow path 81 is returned to a negative pressure. Hereinafter, the cleaning of the ink head 41 by the control of the purge control unit 120 is also referred to as "pressure cleaning".

[0040] The stirring control unit 130 includes a second pressure control unit 131 and a second decompression control unit 132. The second pressure control unit 131 closes the decompression pump 84 and drives the liquid feed pump 83 to pressurize the inside of the ink flow path 81 to a pressure at which ink does not leak from the ink head 41. The second decompression control unit 132 closes the liquid feed pump 83 and drives the decompression pump 84 to decompress the inside of the ink flow path 81 to a pressure at which ink is not drawn into the ink head 41. The stirring control unit 130 repeatedly performs such pressurization and decompression to stir the ink in the ink flow path 81 and the damper 85. Hereinafter, the stirring of the ink by the control of the stirring control unit 130 is also referred to as "in-and-out stirring".

[0041] [Process of Pressure Cleaning] Hereinafter, the process of pressure cleaning will be described. FIG. 6 is a flowchart of pressure cleaning. During pressure cleaning, the valve 82 is open. As shown in FIG. 6, in step S01 of pressure cleaning, the cap 71 is attached to the ink head 41. In step S02 of pressure cleaning, the liquid feed pump 83 is driven. As a result, the pressure of the ink in the ink flow path 81 increases, and the ink leaks from the nozzle 42. The leaked ink is stored in the cap 71.

[0042] In step S03, it is determined whether the pressure of the ink has reached a predetermined pressure. If the pressure of the ink has not reached the predetermined pressure (if the result of step S03 is NO), the state of step S02 is continued. When the pressure of the ink reaches the predetermined pressure (when the result of step S03 becomes YES), after a lapse of a predetermined time, in step S04, the liquid feed pump 83 is stopped. In the present embodiment, the end timing of pressurization is managed by the pressure and time of the ink. In step S04, simultaneously with the stop of the liquid feed pump 83, the decompression pump 84 is driven. As a result, the pressure in the pressurized ink flow path 81 is returned to a negative pressure. The driving of the decompression pump 84 may be slightly prior to the stop of the liquid feed pump 83. This eliminates the time lag when switching from pressurization to decompression.

[0043] In step S05, it is determined whether or not a predetermined time has elapsed since the decompression pump 84 was driven. If the predetermined time has not elapsed (if the result of step S05 is NO), the state of step S04 is continued. When the predetermined time elapses (when the result of step S05 becomes YES), in step S06, the decompression pump 84 is stopped. In the present embodiment, the end timing of decompression is managed by time. However, the end timing of decompression may be managed by, for example, the pressure in the damper 85. The decompression pump 84 may be stopped, for example, when the detection unit 85c of the damper 85 detects that the expansion of the damper diaphragm 85b has become less than a predetermined amount. Or the decompression pump 84 may be stopped after a predetermined time has elapsed since the detection unit 85c detected that the expansion of the damper diaphragm 85b has become less than a predetermined amount.

[0044] [Process of taking in and out and stirring] Next, the process of taking in and out and stirring will be described. FIG. 7 is a flowchart of the process of taking in and out and stirring. During the process of taking in and out and stirring, the valve 82 is open. As shown in FIG. 7, in step S11 of the process of taking in and out and stirring, the liquid feed pump 83 is closed. In step S12, the decompression pump 84 is driven to decompress the inside of the ink flow path 81 to a pressure at which ink is not drawn into the ink head 41. Here, the pressure in the ink flow path 81 is managed by the amount of ink that the decompression pump 84 returns to the ink cartridge 61. The amount of ink that the decompression pump 84 returns to the ink cartridge 61 is managed by the rotation angle of the decompression pump 84. In step S12, the decompression pump 84 is driven, for example, by a rotation angle at which it has been previously confirmed that ink is not drawn into the ink head 41.

[0045] In step S13, it is determined whether the rotation angle of the vacuum pump 84 has reached the predetermined angle. If the predetermined rotation angle has not been reached (if the result of step S13 is NO), the state of step S12 is continued. When the rotation angle of the vacuum pump 84 reaches the predetermined rotation angle (when the result of step S13 becomes YES), in step S14, the vacuum pump 84 is stopped (closed). However, in the vacuum process, for example, the pressure of the ink may be detected, and the vacuum pump 84 may be driven until a predetermined pressure is reached at which it is confirmed in advance that the ink is not drawn into the ink head 41.

[0046] In step S15, the liquid feed pump 83 is driven to pressurize the inside of the ink flow path 81 to a pressure at which the ink does not leak from the ink head 41. The cap 71 may be attached to the ink head 41 in case the ink leaks from the ink head 41. Also here, the pressure inside the ink flow path 81 is controlled by the amount of ink that the liquid feed pump 83 sends to the ink head 41. The amount of ink that the liquid feed pump 83 sends to the ink head 41 is controlled by the rotation angle of the liquid feed pump 83. In step S16, it is determined whether the rotation angle of the liquid feed pump 83 has reached the predetermined angle. If the predetermined rotation angle has not been reached (if the result of step S16 is NO), the state of step S15 is continued. When the rotation angle of the liquid feed pump 83 reaches the predetermined rotation angle (when the result of step S16 becomes YES), in step S17, the liquid feed pump 83 is stopped (closed). However, in the pressurization process, for example, the pressure of the ink may be detected, and the liquid feed pump 83 may be driven until a predetermined pressure is reached at which it is confirmed in advance that the ink does not leak from the ink head 41.

[0047] Hereinafter, although the illustration is omitted, the vacuum process similar to steps S11 to S14 and the pressurization process similar to steps S15 to S17 are repeated a predetermined number of times. However, the vacuum process and the pressurization process may each be performed once. Also, the pressurization process may be performed before the vacuum process.

[0048] By alternately driving the vacuum pump 84 and the liquid feed pump 83, the discharge of ink from the damper 85 and the supply of ink to the damper 85 are alternately performed. As a result, the ink in the ink flow path 81 and the damper 85 is agitated. By performing such agitation at an appropriate time, sedimentation of the components of the ink is suppressed. For example, in the case of solvent ink, sedimentation of the pigment of the ink, particularly the pigment of white ink, is suppressed.

[0049] [Operational Effects of the First Embodiment] Hereinafter, the operational effects that the printer 10 according to the first embodiment can exhibit will be described.

[0050] The printer 10 according to the present embodiment includes an ink cartridge 61 that stores ink, an ink head 41 that discharges ink, an ink flow path 81 that includes a first flow path 81b and a second flow path 81c and connects the ink cartridge 61 and the ink head 41, a liquid feed pump 83 that is provided in the first flow path 81b and sends ink in a direction from the ink cartridge 61 toward the ink head 41, and a vacuum pump 84 that is provided in the second flow path 81c and sends ink in a direction from the ink head 41 toward the ink cartridge 61.

[0051] According to the printer 10 according to the present embodiment, the inside of the ink flow path 81 can be pressurized by driving the liquid feed pump 83, and the inside of the ink flow path 81 can be depressurized by driving the vacuum pump 84. Since the liquid feed pump 83 and the vacuum pump 84 are separate pumps, a time lag between pressurization and depressurization can be suppressed.

[0052] If the liquid feed pump and the pressure reducing pump are integrated into one pump and configured to rotate forward during liquid feeding and reverse during pressure reduction, the number of components can be reduced. However, a time lag occurs when switching the rotation direction of the pump from forward to reverse. During the time lag, the pump is stopped. When the ink is discharged under pressure, ink accumulates on the surface of the nozzle, and the ink accumulated in adjacent nozzles gathers. When the liquid feed pump is stopped after pressure cleaning, due to the pressure difference between the nozzles during the time when the pump is stopped due to the time lag, the ink that has gathered and mixed colors is drawn into the nozzle with a lower internal pressure. In this case, ink color mixing in printing occurs over a long period or at unexpected timings. When the pump is stopped with a cap attached to the ink head after pressure cleaning, the color mixing becomes even more severe.

[0053] According to the printer 10 according to the present embodiment, in pressure cleaning, it is possible to suppress the time lag between pressurization and depressurization. Immediately after the pressurization in the ink flow path 81 is completed, if the inside of the ink flow path 81 is depressurized immediately, there is no time for the ink accumulated in the adjacent nozzles 42 to mix colors. Therefore, the risk of the mixed ink being drawn into the nozzles 42 is reduced.

[0054] In the present embodiment, the control device 100 includes a first pressurization control unit 121 that closes the pressure reducing pump 84 and drives the liquid feed pump 83 to pressurize the inside of the ink flow path 81 up to the pressure at which the ink leaks from the ink head 41, and a first depressurization control unit 122 that closes the liquid feed pump 83 and drives the pressure reducing pump 84 to depressurize the inside of the ink flow path 81. According to such a configuration, after pressurizing the inside of the ink flow path 81 to cause the ink to leak from the ink head 41 and cleaning the nozzles 42, by driving the pressure reducing pump 84, the inside of the ink flow path 81 can be returned to a negative pressure.

[0055] The printer 10 according to this embodiment is configured to be able to store ink and includes a damper 85 communicating with an ink head 41. The ink flow path 81 is connected to the upstream end of the first flow path 81b and the upstream end of the second flow path 81c, and includes a first branch portion 81e communicating with the ink cartridge 61, a downstream common flow path 81d having its downstream end connected to the damper 85, and a second branch portion 81f connected to the downstream end of the first flow path 81b, the downstream end of the second flow path 81c, and the upstream end of the downstream common flow path 81d. The control device 100 includes a second decompression control unit 132 that closes the liquid feed pump 83 and drives the decompression pump 84 to decompress the inside of the ink flow path 81 to a pressure at which ink is not drawn into the ink head 41, and a second pressurization control unit 131 that closes the decompression pump 84 and drives the liquid feed pump 83 to pressurize the inside of the ink flow path 81 to a pressure at which ink does not leak from the ink head 41. According to such a configuration, it is possible to supply ink to the damper 85 and perform the intake and discharge stirring to discharge it from the damper 85. By the intake and discharge stirring, the ink in the ink flow path 81, particularly in the damper 85, can be stirred, and sedimentation of components can be suppressed.

[0056] [Second Embodiment] In the second embodiment, a flow path for circulating ink is added to the ink flow path 81. FIG. 8 is a schematic diagram showing the configuration of an ink supply system 80 according to the second embodiment. As shown in FIG. 8, the ink flow path 81 according to this embodiment includes a third flow path 81g having one end connected to the first branch portion 81e and the other end connected to the damper 85. The printer 10 includes a second valve 86 provided in the third flow path 81g. Hereinafter, the valve 82 provided in the upstream common flow path 81a is also referred to as the first valve 82 for distinction from the second valve 86. The first branch portion 81e may include a joint that branches in four directions as shown in the configuration of FIG. 8, or may be composed of, for example, two branches. As long as the connection relationship between the flow paths is the same, the configuration of the branch portion is not particularly limited.

[0057] FIG. 9 is a block diagram of the printer 10 according to the second embodiment. As shown in FIG. 9, the printer 10 according to the second embodiment includes a circulation control unit 140 in addition to the configuration of the printer 10 according to the first embodiment. The circulation control unit 140 includes a first circulation control unit 141, a second circulation control unit 142, a third pressure control unit 143, and a third decompression control unit 144.

[0058] The first circulation control unit 141 closes the first valve 82 and the decompression pump 84, opens the second valve 86, and drives the liquid feed pump 83. Thereby, the first circulation control unit 141 circulates the ink in the direction of arrow C1 in FIG. 8. Hereinafter, this ink circulation direction is also referred to as the forward direction. The second circulation control unit 142 closes the first valve 82 and the liquid feed pump 83, opens the second valve 86, and drives the decompression pump 84. Thereby, the second circulation control unit 142 circulates the ink in the direction of arrow C2 in FIG. 8. Hereinafter, this ink circulation direction is also referred to as the reverse direction. The circulation control unit 140 is configured to be capable of both forward circulation and reverse circulation. Hereinafter, a circulation that alternately performs forward circulation and reverse circulation is also referred to as bidirectional circulation.

[0059] The third pressure control unit 143 opens the first valve 82, closes the second valve 86 and the decompression pump 84, and drives the liquid feed pump 83 to pressurize the inside of the damper 85. In the present embodiment, the printer 10 can perform forward circulation, reverse circulation, or bidirectional circulation in a state where the inside of the damper 85 is pressurized under the control of the third pressure control unit 143. The first circulation control unit 141 and the second circulation control unit 142 function as a third circulation control unit that closes the first valve 82 and opens the second valve 86 in a state where the inside of the damper 85 is pressurized under the control of the third pressure control unit 143, and further drives one of the liquid feed pump 83 and the decompression pump 84 and closes the other.

[0060] The third pressure reduction control unit 144 opens the first valve 82, closes the second valve 86 and the liquid feed pump 83, and drives the pressure reduction pump 84 to reduce the pressure inside the damper 85. In the present embodiment, the printer 10 can perform forward circulation, reverse circulation, or bidirectional circulation in a state where the pressure inside the damper 85 is reduced under the control of the third pressure reduction control unit 144. The first circulation control unit 141 and the second circulation control unit 142 function as a fourth circulation control unit that closes the first valve 82 and opens the second valve 86 in a state where the pressure inside the damper 85 is reduced under the control of the third pressure reduction control unit 144, and further drives one of the liquid feed pump 83 and the pressure reduction pump 84 and closes the other.

[0061] Hereinafter, the ink circulation performed by pressurizing the inside of the damper 85 is referred to as pressurization circulation, and the ink circulation performed by reducing the pressure inside the damper 85 is referred to as pressure reduction circulation. Further, the pressurization circulation and the pressure reduction circulation are collectively referred to as pressure adjustment circulation. The combination of pressurization / decompression and the ink circulation direction is expressed, for example, as pressurization - forward circulation, pressure reduction - bidirectional circulation.

[0062] [Process of pressure adjustment circulation] FIG. 10 is a flowchart showing an example of the pressure adjustment circulation. Hereinafter, with reference to FIG. 10, the process of pressurization - bidirectional circulation as an example of the pressure adjustment circulation will be described.

[0063] As shown in FIG. 10, in the pressurization - bidirectional circulation step S21, the first valve 82 is opened and the second valve 86 and the decompression pump 84 are closed. In the subsequent step S22, the liquid feed pump 83 is driven to pressurize the inside of the damper 85. Since the first valve 82 is open, when the liquid feed pump 83 is driven, the ink moves from the ink cartridge 61 to the damper 85. Since the second valve 86 and the decompression pump 84 are closed, the ink does not circulate and heads towards the damper 85. As a result, the inside of the damper 85 is pressurized. The damper 85 expands due to the pressurization. In step S22, the inside of the ink flow path 81 is pressurized to a pressure at which ink does not leak from the ink head 41. In case ink leaks from the ink head 41, the cap 71 may be attached to the ink head 41. Here too, the pressure inside the ink flow path 81 is controlled by the amount of ink that the liquid feed pump 83 sends to the ink head 41. When the rotation angle of the liquid feed pump 83 reaches a predetermined rotation angle, in step S23, the liquid feed pump 83 is stopped. Note that since the liquid feed pump 83 is driven again in the subsequent step S25, if possible, it may not be stopped.

[0064] In step S24, the first valve 82 is closed and the second valve 86 is opened. As a result, the damper 85 and the ink cartridge 61 are blocked, and the third flow path 81g for ink circulation is opened. In step S25, the liquid feed pump 83 is driven. At this time, the decompression pump 84 is closed. By step S25, the ink circulates in the C1 direction of FIG. 8 while being pressurized.

[0065] When a predetermined time elapses from the start of step S25, in step S26, the liquid feed pump 83 is stopped (closed). In step S27, the decompression pump 84 is driven. By step S27, the ink circulates in the C2 direction in FIG. 8 in a pressurized state. When a predetermined time elapses from the start of step S27, in step S28, the decompression pump 84 is stopped (closed). By steps S25 to S28, one pressurization - bidirectional circulation is completed. Although illustration is omitted, thereafter, steps S25 to S26 and steps S27 to S28 may be alternately repeated. However, as shown in FIG. 10, steps S25 to S26 and steps S27 to S28 may be alternately performed only once. In the bidirectional circulation, the circulation in the C2 direction may be performed prior to the circulation in the C1 direction. By the end of the repetition of steps S25 to S26 and steps S27 to S28, the pressurization - bidirectional circulation ends. However, thereafter, for example, a step of decompressing the pressure in the ink flow path 81 may be performed.

[0066] When performing decompression circulation, in the step corresponding to step S21, the first valve 82 may be opened, and the second valve 86 and the liquid feed pump 83 may be closed. Further, in the step corresponding to step S22, the decompression pump 84 may be driven to decompress the inside of the damper 85. When performing forward circulation, steps S27 and S28 may be omitted. When performing reverse circulation, steps S25 and S26 may be omitted.

[0067] Note that also in this embodiment, the pressurization cleaning and the in - and - out stirring may be performed in the same manner as in the first embodiment. In this embodiment, during pressurization cleaning and in - and - out stirring, the second valve 86 is closed. A forward circulation, a reverse circulation, or a bidirectional circulation without pressurization or decompression may be performed. In that case, steps S21 to S23 are omitted. In this embodiment, many variations of ink stirring, such as in - and - out stirring, pressurization / decompression circulation, and forward / reverse / bidirectional circulation, can be implemented.

[0068] [Operation and Effect of the Second Embodiment] The following describes the effects that the printer 10 according to the second embodiment can achieve.

[0069] In the present embodiment, the ink flow path 81 includes an upstream common flow path 81a whose upstream end is connected to the ink cartridge 61 and whose downstream end is connected to the first branch portion 81e, and a third flow path 81g whose upstream end is connected to the first branch portion 81e and whose downstream end is connected to the damper 85. The printer 10 includes a first valve 82 provided in the upstream common flow path 81a and a second valve 86 provided in the third flow path 81g. According to such a configuration, ink can be made to flow through the third flow path 81g and circulated. By circulating the ink, the ink can also be stirred and sedimentation of components can be suppressed.

[0070] In the present embodiment, the control device 100 includes a first circulation control unit 141 that closes the first valve 82 and the decompression pump 84, opens the second valve 86, and drives the liquid feed pump 83, and a second circulation control unit 142 that closes the first valve 82 and the liquid feed pump 83, opens the second valve 86, and drives the decompression pump 84. According to such a configuration, bidirectional circulation in which the circulation direction of the ink is changed midway can be performed. According to the bidirectional circulation, due to the turbulent flow when the circulation direction is switched, ink in locations where it is difficult to stir the ink, for example, near the wall surfaces of the ink flow path 81 and the damper 85 where the ink flow is slow, can be efficiently stirred.

[0071] In this embodiment, the control device 100 includes a third pressurization control unit 143 that opens the first valve 82, closes the second valve 86 and the pressure reducing pump 84, and drives the liquid feeding pump 83 to pressurize the inside of the damper 85. The control device 100 closes the first valve 82 and opens the second valve 86 in a state where the inside of the damper 85 is pressurized by the control of the third pressurization control unit 143, and is further configured to drive one of the liquid feeding pump 83 and the pressure reducing pump 84 and close the other. According to such a configuration, the ink can be circulated in a state where the inside of the damper 85 is pressurized. In the pressurized state, the amount of ink in the damper 85 is large. Therefore, it is possible to efficiently stir the ink in a place where the ink is difficult to be stirred, for example, near the corner of the internal space of the damper 85.

[0072] In this embodiment, the control device 100 includes a third pressure reduction control unit 144 that opens the first valve 82, closes the second valve 86 and the liquid feeding pump 83, and drives the pressure reducing pump 84 to reduce the pressure in the damper 85. The control device 100 closes the first valve 82 and opens the second valve 86 in a state where the inside of the damper 85 is depressurized by the control of the third pressure reduction control unit 144, and is further configured to drive one of the liquid feeding pump 83 and the pressure reducing pump 84 and close the other. According to such a configuration, the ink can be circulated in a state where the inside of the damper 85 is depressurized. In the depressurized state, the amount of ink in the damper 85 is small. Therefore, the ink is easily stirred as a whole.

[0073] [Third Embodiment] In the third embodiment, the first flow path 81b and the second flow path 81c are also used as circulation flow paths. FIG. 11 is a schematic diagram showing the configuration of the ink supply system 80 according to the third embodiment. As shown in FIG. 11, in this embodiment, the downstream end of the first flow path 81b and the downstream end of the second flow path 81c are connected to the damper 85.

[0074] FIG. 12 is a block diagram of the printer 10 according to the third embodiment. As shown in FIG. 12, the control device 100 according to the third embodiment includes a supply control unit 110, a purge control unit 120, and a stirring control unit 130 similar to those of the control device 100 according to the first embodiment. The control device 100 according to the third embodiment includes an ink circulation unit 150 that performs a circulation control different from that of the control device 100 according to the second embodiment.

[0075] The ink circulation unit 150 controls the operations of the respective parts in the pressure adjustment circulation. As shown in FIG. 12, the ink circulation unit 150 includes a pressurization control unit 151, a depressurization control unit 152, and a circulation control unit 153. The pressurization control unit 151 opens the valve 82, closes the depressurization pump 84, and drives the liquid feed pump 83 to pressurize the inside of the damper 85. The depressurization control unit 152 opens the valve 82, closes the liquid feed pump 83, and drives the depressurization pump 84 to depressurize the inside of the damper 85. The circulation control unit 153 closes the valve 82 in a state where the inside of the damper 85 is pressurized by the control of the pressurization control unit 151 or in a state where the inside of the damper 85 is depressurized by the control of the depressurization control unit 152. The circulation control unit 153 further drives the liquid feed pump 83 and the depressurization pump 84, or drives one of the liquid feed pump 83 and the depressurization pump 84 and opens the other. By such control, the circulation control unit 153 circulates the ink in the ink flow path 81 in the C3 direction of FIG. 11.

[0076] Here, the circulation control unit 153 drives the liquid feed pump 83 and releases the pressure reducing pump 84 in a state where the inside of the damper 85 is pressurized by the control of the pressurization control unit 151 or in a state where the inside of the damper 85 is depressurized by the control of the depressurization control unit 152. However, the circulation control unit 153 may be configured to release the liquid feed pump 83 and drive the pressure reducing pump 84 in a state where the inside of the damper 85 is pressurized by the control of the pressurization control unit 151 or in a state where the inside of the damper 85 is depressurized by the control of the depressurization control unit 152. Alternatively, the circulation control unit 153 may be configured to drive both the liquid feed pump 83 and the pressure reducing pump 84 in a state where the inside of the damper 85 is pressurized by the control of the pressurization control unit 151 or in a state where the inside of the damper 85 is depressurized by the control of the depressurization control unit 152.

[0077] [Process of pressure adjustment circulation] FIG. 13 is a flowchart showing an example of pressure adjustment circulation by the printer 10 according to the third embodiment. Hereinafter, with reference to FIG. 13, the process of pressurization circulation as an example of pressure adjustment circulation will be described.

[0078] As shown in FIG. 13, in step S31 of the pressure adjustment circulation by the printer 10 according to the present embodiment, the valve 82 is opened and the pressure reducing pump 84 is closed. In step S32, the liquid feed pump 83 is driven to pressurize the inside of the damper 85. Since the pressure reducing pump 84 is closed, ink does not escape from the damper 85 to the second flow path 81c, so the inside of the damper 85 is pressurized. In step S33, the liquid feed pump 83 is stopped. Note that since the liquid feed pump 83 is driven again in step S35 later, it may not be stopped if possible.

[0079] In step S34, valve 82 is closed. In step S35, the pressure reducing pump 84 is released. In step S36, the liquid feeding pump 83 is driven. As a result, the ink circulates in the C3 direction of FIG. 11 in a pressurized state. When a predetermined time has elapsed since the start of step S36, in step S37, the liquid feeding pump 83 is stopped (closed). With the end of step S37, the pressurized circulation ends. However, thereafter, for example, a step of reducing the pressure in the ink flow path 81 may be performed.

[0080] When performing decompression circulation, in a step corresponding to step S31, valve 82 may be opened and the liquid feeding pump 83 may be closed. Further, in a step corresponding to step S32, the pressure reducing pump 84 may be driven to decompress the inside of the damper 85. Note that ink circulation without pressure increase or decrease may be performed. In that case, steps S31 to S33 are omitted.

[0081] [Operation and Effect of the Third Embodiment] Hereinafter, the operation and effect that the printer 10 according to the third embodiment can exhibit will be described.

[0082] In the present embodiment, the downstream end of the first flow path 81b and the downstream end of the second flow path 81c are connected to the damper 85. According to such a configuration, even without providing a circulation flow path such as the third flow path 81g, the internal space of the damper 85 can be used to configure a circulation flow path including the damper 85.

[0083] In the present embodiment, the control device 100 includes a pressure increasing control unit 151 that opens the valve 82, closes the pressure reducing pump 84, and drives the liquid feeding pump 83 to pressurize the inside of the damper 85, and the valve 82 is closed in a state where the inside of the damper 85 is pressurized by the control of the pressure increasing control unit 151, and further, the liquid feeding pump 83 and the pressure reducing pump 84 are driven, or one of the liquid feeding pump 83 and the pressure reducing pump 84 is driven and the other is opened. According to such a configuration, pressurized circulation similar to that of the second embodiment can be performed with a simple configuration.

[0084] In this embodiment, the control device 100 includes a pressure reduction control unit 152 that opens the valve 82, closes the liquid feed pump 83, and drives the pressure reduction pump 84 to reduce the pressure inside the damper 85. The circulation control unit 153 closes the valve 82 in a state where the pressure inside the damper 85 is reduced by the control of the pressure reduction control unit 152, and further drives the liquid feed pump 83 and the pressure reduction pump 84, or drives one of the liquid feed pump 83 and the pressure reduction pump 84 and releases the other. According to such a configuration, pressure reduction circulation similar to that of the second embodiment can be performed with a simple configuration.

[0085] [Other Embodiments] As described above, several preferred embodiments have been described. However, the printer of the present invention is not limited to the above-described embodiments. For example, the configuration of the ink supply system 80 is not limited to the above-described one. Other pipes, other valves, etc. may be further added to the ink supply system 80. Alternatively, for example, from the first embodiment, the valve 82 may be omitted.

[0086] The processes of pressure cleaning, taking in and out and stirring, pressure increase / decrease circulation, and forward / reverse / bidirectional circulation in the above-described embodiments are merely examples. Pressure cleaning, taking in and out and stirring, pressure increase / decrease circulation, and forward / reverse / bidirectional circulation can also be implemented by other processes.

[0087] In the above-described embodiment, the printer 10 was a flatbed type printer, but the configuration of the printer is not particularly limited. The technology disclosed herein may be applied, for example, to a printer in which a recording medium is supplied from a roll. In addition, the configuration of the printer 10 described above is merely an example and is not particularly limited.

[0088] In addition, unless otherwise specified, the embodiments do not limit the present invention.

Description of Reference Numerals

[0089] 10 Inkjet Printer (Printer) 41 Ink head 61 Ink cartridge (ink container) 80 Ink supply system 81 Ink flow path 81a Upstream common flow path (common flow path, second common flow path) 81b First flow path 81c Second flow path 81d Downstream common flow path (first common flow path) 81e First branch portion (branch portion) 81f Second branch portion 81g Third flow path 82 Valve (first valve) 83 Liquid feed pump 84 Vacuum pump 85 Damper (intermediate container) 86 Second valve 100 Control device 121 First pressure control unit 122 First vacuum control unit 131 Second pressure control unit (fourth pressure control unit) 132 Second vacuum control unit (fourth vacuum control unit) 141 First circulation control unit (third circulation control unit, fourth circulation control unit) 142 Second circulation control unit (third circulation control unit, fourth circulation control unit) 143 Third pressure control unit 144 Third vacuum control unit 151 Pressure control unit (fifth pressure control unit) 152 Vacuum control unit (fifth vacuum control unit) 153 Circulation control unit (fifth circulation control unit, sixth circulation control unit)

Claims

1. An ink container containing ink, An ink head from which ink is ejected, An ink flow path including a first flow path and a second flow path, connecting the ink container and the ink head, A liquid feeding pump provided in the first flow path, for sending ink in the direction from the ink container toward the ink head, A pressure reducing pump provided in the second flow path, for sending ink in the direction from the ink head toward the ink container, and A printer.

2. Further comprising a control device for controlling the liquid feeding pump and the pressure reducing pump, The control device, A first pressurizing control unit that closes the pressure reducing pump and drives the liquid feeding pump to pressurize the inside of the ink flow path to a pressure at which ink leaks from the ink head, A first pressure reducing control unit that closes the liquid feeding pump and drives the pressure reducing pump to reduce the pressure inside the ink flow path, and The printer according to Claim 1.

3. Further comprising an intermediate container configured to be able to store ink and communicating with the ink head, The ink flow path, A first branch portion connected to one end of the first flow path and one end of the second flow path and communicating with the ink container, A first common flow path having one end connected to the intermediate container, And a second branch portion connected to the other end of the first flow path, the other end of the second flow path, and the other end of the first common flow path, and The printer according to Claim 1.

4. Further comprising a control device for controlling the liquid feeding pump and the pressure reducing pump, The control device, A second pressure reducing control unit that closes the liquid feeding pump and drives the pressure reducing pump to reduce the pressure inside the ink flow path to a pressure at which ink is not drawn into the ink head, A second pressurizing control unit that closes the pressure reducing pump and drives the liquid feeding pump to pressurize the inside of the ink flow path to a pressure at which ink does not leak from the ink head, and The printer according to Claim 3.

5. The ink flow path, A second common flow path having one end connected to the ink container and the other end connected to the first branch portion, A third flow path having one end connected to the first branch portion and the other end connected to the intermediate container, and A first valve provided in the second common flow path, A second valve provided in the third flow path, and The printer according to Claim 3.

6. Further comprising a control device for controlling the liquid feeding pump, the pressure reducing pump, the first valve, and the second valve, The control device, A first circulation control unit that closes the first valve and the decompression pump, opens the second valve, and drives the liquid feed pump; A second circulation control unit that closes the first valve and the liquid feed pump, opens the second valve, and drives the decompression pump; and the printer is provided with the second circulation control unit. The printer according to claim 5.

7. The printer further includes a control device that controls the liquid feed pump, the decompression pump, the first valve, and the second valve. The control device is A third pressurization control unit that opens the first valve, closes the second valve and the decompression pump, and drives the liquid feed pump to pressurize the inside of the intermediate container; A third circulation control unit that closes the first valve and opens the second valve while the inside of the intermediate container is pressurized by the control of the third pressurization control unit, and further drives one of the liquid feed pump and the decompression pump and closes the other; and the printer is provided with the third circulation control unit. The printer according to claim 5.

8. The printer further includes a control device that controls the liquid feed pump, the decompression pump, the first valve, and the second valve. The control device is A third decompression control unit that opens the first valve, closes the second valve and the liquid feed pump, and drives the decompression pump to decompress the inside of the intermediate container; A fourth circulation control unit that closes the first valve and opens the second valve while the inside of the intermediate container is decompressed by the control of the third decompression control unit, and further drives one of the liquid feed pump and the decompression pump and closes the other; and the printer is provided with the fourth circulation control unit. The printer according to claim 5.

9. The printer further includes an intermediate container configured to store ink and communicate with the ink head. The ink flow path is connected to one end of the first flow path and one end of the second flow path, and includes a branch portion communicating with the ink container. The other end of the first flow path and the other end of the second flow path are connected to the intermediate container. The printer according to claim 1.

10. The printer further includes a control device that controls the liquid feed pump and the decompression pump. The control device is A fourth decompression control unit that closes the liquid feed pump and drives the decompression pump to decompress the inside of the ink flow path to a pressure at which ink is not drawn into the ink head. A fourth pressure control unit that closes the vacuum pump and drives the liquid feed pump to pressurize the inside of the ink flow path to a pressure at which ink does not leak from the ink head; The printer according to claim 9.

11. The ink flow path includes a common flow path having one end connected to the ink container and the other end connected to the branch portion. A valve provided in the common flow path; The liquid feed pump, the vacuum pump, and a control device that controls the valve; The control device is A fifth pressure control unit that opens the valve, closes the vacuum pump, and drives the liquid feed pump to pressurize the inside of the intermediate container; A fifth circulation control unit that closes the valve in a state where the inside of the intermediate container is pressurized by the control of the fifth pressure control unit, and further drives the liquid feed pump and the vacuum pump, or drives one of the liquid feed pump and the vacuum pump and opens the other; The printer according to claim 9.

12. The ink flow path includes a common flow path having one end connected to the ink container and the other end connected to the branch portion. A valve provided in the common flow path; The liquid feed pump, the vacuum pump, and a control device that controls the valve; The control device is A fifth pressure reduction control unit that opens the valve, closes the liquid feed pump, and drives the vacuum pump to reduce the pressure in the intermediate container; A sixth circulation control unit that closes the valve in a state where the inside of the intermediate container is depressurized by the control of the fifth pressure reduction control unit, and further drives the liquid feed pump and the vacuum pump, or drives one of the liquid feed pump and the vacuum pump and opens the other; The printer according to claim 9.

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