Printer

Abstract

To confirm that a liquid feeding pump has been closed, without utilizing a hydraulic head pressure of ink.SOLUTION: A printer comprises: an ink container 61 storing ink; an ink head 41 that discharges ink; an ink flow passage 81 through which the ink container 61 is connected to the ink head 41; a liquid feeding pump 83 that feeds ink in a direction from the ink container 61 toward the ink head 41; a pressure detecting device 85b that detects the pressure in the ink flow passage 81; and a control device. The liquid feeding pump 83 is configured to be switchable between an opened state where an internal flow passage is opened and a closed state where the internal flow passage is closed by an extruding member, which feeds ink by driving a driving part, in the closed state. The control device makes the extruding member close the internal flow passage and drives the driving part so as to feed ink, and when the pressure detected by the pressure detecting device 85b reaches a predetermined determination pressure, before a predetermined time elapses after the driving part starts to feed ink, determines that the liquid feeding pump 83 has been closed.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a printer.

Background Art

[0002] Conventionally known printers include an ink container containing ink, an ink head from which ink is ejected, an ink flow path connecting the ink container and the ink head, and a liquid feed pump provided in the ink flow path for sending ink in a direction from the ink container toward the ink head. Among such printers, those having a function of checking for abnormal closure of the liquid feed pump are also conventionally known. For example, Patent Document 1 discloses an inkjet printer including a damper having a storage chamber connected to an ink head, and a detection mechanism for detecting the pressure in the storage chamber, wherein the ink tank is disposed above the ink head. The inkjet printer of Patent Document 1 ejects ink from the ink head and closes the liquid feed pump to check whether the liquid feed pump can be normally closed. When the liquid feed pump cannot be closed, ink flows into the storage chamber due to the hydrostatic pressure of the ink, and the pressure in the storage chamber is maintained despite the ejection of ink. The inkjet printer of Patent Document 1 determines that the closure of the liquid feed pump is abnormal when the pressure in the storage chamber is maintained.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the inkjet printer described in Patent Document 1, the hydrostatic pressure of the ink is used to determine whether the liquid feed pump is closed. However, for example, when the ink container and the ink head are arranged at a similar height, since the hydrostatic pressure is weak, even if the liquid feed pump is not closed, it cannot be detected.

[0005] The present invention has been made in view of such a point, and an object thereof is to provide a printer that can confirm the closure of the liquid feed pump without using the hydrostatic pressure of the ink applied to the liquid feed pump.

Means for Solving the Problem

[0006] The printer disclosed herein includes an ink container that stores ink, an ink head that has a plurality of nozzles from which the ink is ejected, an ink flow path that connects the ink container and the ink head and communicates the ink container and the plurality of nozzles, a liquid feed pump that is provided in the ink flow path and sends the ink in a direction from the ink container toward the ink head, a pressure detection device that detects the pressure in a portion of the ink flow path on the ink head side of the liquid feed pump, and a control device that controls the liquid feed pump. The liquid feed pump includes an internal flow path, a pressing member that squeezes the internal flow path, and a driving unit that runs the pressing member along the internal flow path. The liquid feed pump is configured to be switchable between an open state in which the internal flow path is open and a closed state in which the internal flow path is closed by the pressing member, and is configured to send the ink by driving the driving unit in the closed state. The control device includes a liquid feed control unit that closes the internal flow path by the pressing member and drives the driving unit to send the ink, and a determination unit that determines that the liquid feed pump is closed when the pressure detected by the pressure detection device reaches a predetermined determination pressure before a predetermined time elapses after the liquid feed control unit starts sending the ink.

[0007] In the above printer, the liquid feeding pump sends ink by running the extrusion member with the internal flow path closed by the extrusion member. Therefore, if the closing of the internal flow path by the extrusion member is insufficient, the amount of ink fed decreases. As a result, even after a predetermined time has elapsed since starting to feed the ink, the pressure detected by the pressure detection device remains below the predetermined determination pressure. The above printer determines that the liquid feeding pump has been successfully closed when the pressure detected by the pressure detection device reaches the predetermined determination pressure before a predetermined time has elapsed since starting to feed the ink. Thus, according to the above printer, it is possible to confirm the closing of the liquid feeding pump without using the head pressure of the ink applied to the liquid feeding pump.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

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. Also, members and parts having the same function are denoted by the same reference numerals, and redundant descriptions are omitted or simplified as appropriate.

[0010] [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 the front, and the direction approaching the printer 10 is the rear. Left, right, up, and down mean left, right, up, and down when the printer 10 is viewed from the front, respectively. Also, in the drawings, the reference signs F, Rr, L, R, U, and D mean front, rear, left, right, up, and down, respectively. However, the above directions are merely set for 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 part 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 as an axis. 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, in the internal space of the printer 10, 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, a wiping device 75, and a control device 100 (see FIG. 1) are provided. 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 for supporting the recording medium 5. The printer 10 according to this 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 in the internal space of the case 11.

[0015] Below the flat bed 20, a bed moving device 25 is arranged. The bed moving device 25 moves the flat bed 20 in the front-rear direction and the up-down direction. The flat bed 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 flat bed 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 opposite up-down positional relationship.

[0016] The carriage 30 mounts a recording head 40 and a light irradiation device 50. The carriage 30 is provided above the flat bed 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. 6).

[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. FIG. 3 is a plan view showing the configuration of the lower surface of the carriage 30. As shown in FIG. 3, the recording head 40 includes a plurality of ink heads 41 and 42. The first ink head 41 and the second ink head 42 are provided side by side in the left-right direction. The first ink head 41 and the second ink head 42 both extend in the front-rear direction. In the present embodiment, the first ink head 41 discharges inks of a plurality of colors. The first ink head 41 has a plurality of nozzle rows 43A to 43D that extend in the front-rear direction respectively. The nozzle row 43A is composed of a plurality of nozzles 44A arranged in the front-rear direction. Inks are discharged from each of the plurality of nozzles 44A. The nozzle row 43B is composed of a plurality of nozzles 44B, the nozzle row 43C is composed of a plurality of nozzles 44C, and the nozzle row 43D is composed of a plurality of nozzles 44D. Inks of different types are discharged from the nozzles 44A, 44B, 44C, and 44D. Here, inks of different colors are discharged from the nozzles 44A, 44B, 44C, and 44D. The lower surface of the first ink head 41 constitutes a nozzle surface 41S on which a plurality of nozzles 44A to 44D are formed.

[0019] In the present embodiment, the second ink head 42 also discharges inks of a plurality of colors. The second ink head 42 has a plurality of nozzle rows 43E to 43H that extend in the front-rear direction respectively. The nozzle row 43E is composed of a plurality of nozzles 44E, the nozzle row 43F is composed of a plurality of nozzles 44F, the nozzle row 43G is composed of a plurality of nozzles 44G, and the nozzle row 43H is composed of a plurality of nozzles 44H. Inks of different colors are discharged from the nozzles 44E, 44F, 44G, and 44H. The lower surface of the second ink head 42 constitutes a nozzle surface 42S on which a plurality of nozzles 44E to 44H are formed. Hereinafter, when it is not necessary to distinguish the plurality of nozzle rows 43A to 43H, the symbol 43 may be used as the symbol of the nozzle row. Also, when it is not necessary to distinguish the plurality of nozzles 44A to 44H, the symbol 44 may be used as the symbol of the nozzle.

[0020] In this embodiment, the ink ejected from the nozzles 44 of the recording head 40 is photocurable ink. The photocurable ink is, here, 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 thermosetting ink.

[0021] The light irradiation device 50 is provided to the left of the recording head 40. The light irradiation device 50 irradiates the flat bed 20 with light for curing the photocurable ink. The light irradiation device 50 has, for example, a light source (not shown) composed of a plurality of ultraviolet irradiation LEDs. As shown in FIG. 3, the light irradiation device 50 is provided with an irradiation port 51 that opens downward and transmits the light generated by the light source.

[0022] As shown in FIG. 2, the ink cartridge accommodating portion 60 is configured to be able to accommodate a plurality of ink cartridges 61. Hereinafter, the plurality of ink cartridges 61 will be appropriately referred to as ink cartridges 61A to 61H, respectively. The ink cartridges 61A to 61H are each an example of an ink container in which ink is accommodated. In the ink cartridges 61A to 61H, pouches in which ink is stored are respectively accommodated. The ink cartridges 61A to 61H are detachable from the ink cartridge accommodating portion 60. However, the ink container is not limited to an ink cartridge, and may be, for example, a pouch or a container in which ink poured from a bottle or the like is stored. At least two different types of ink are accommodated in the ink cartridges 61A to 61D connected to the first ink head 41, and at least two different types of ink are accommodated in the ink cartridges 61E to 61H connected to the second ink head 42. Here, the plurality of ink cartridges 61A to 61H accommodate inks of different colors from each other.

[0023] In this embodiment, the ink cartridge housing portion 60 is disposed at substantially the same vertical position as the first ink head 41 and the second ink head 42. The plurality of ink cartridges 61A to 61H are disposed at positions overlapping the first ink head 41 and the second ink head 42 in the vertical direction.

[0024] The capping device 70 includes a plurality of caps 71A, 71B, a cap moving device 72, and a plurality of suction pumps 73A, 73B. FIG. 4 is a schematic diagram showing the configuration of the ink supply system 80 and the capping device 70. As shown in FIG. 4, the first cap 71A corresponds to the first ink head 41. The first suction pump 73A corresponds to the first ink head 41. The second cap 71B and the second suction pump 73B correspond to the second ink head 42.

[0025] The first cap 71A is configured to be attachable to the first ink head 41. The first cap 71A has a container-like shape with an open top surface. The first cap 71A is configured to cover the plurality of nozzles 44A to 44D of the first ink head 41 and to be able to accommodate the ink discharged from the plurality of nozzles 44A to 44D. The first cap 71A is formed of rubber or the like. When attached to the first ink head 41, the upper edge of the first cap 71A is in close contact with the nozzle surface 41S of the first ink head 41. The first cap 71A is attached to the first ink head 41 to protect the first ink head 41 and prevent its drying. The second cap 71B is configured in the same manner as the first cap 71A and is configured to be attachable to the second ink head 42. The second cap 71B is configured to cover the plurality of nozzles 44E to 44H of the second ink head 42 and to be able to accommodate the ink discharged from the plurality of nozzles 44E to 44H.

[0026] The plurality of caps 71A and 71B are supported by a cap moving device 72. The number of cap moving devices 72 is one here. The cap moving device 72 attaches the first cap 71A to the first ink head 41 and the second cap 71B to the second ink head 42. Also, the cap moving device 72 separates the first cap 71A from the first ink head 41 and separates the second cap 71B from the second ink head 42. Here, the cap moving device 72 supports the plurality of caps 71A and 71B from below and moves them in the vertical direction. The cap moving device 72 includes, for example, a drive motor (not shown). In the present embodiment, the cap moving device 72 moves the first cap 71A and the second cap 71B simultaneously in the vertical direction and attaches them to the first ink head 41 and the second ink head 42, respectively. However, the cap moving device 72 may be configured to slide the first cap 71A and the second cap 71B diagonally and attach them to the first ink head 41 and the second ink head 42, respectively.

[0027] As shown in FIG. 4, a first suction pump 73A is connected to the first cap 71A. The first suction pump 73A depressurizes the inside of the first cap 71A and sucks the ink discharged into the first cap 71A. A second suction pump 73B depressurizes the inside of the second cap 71B and sucks the ink discharged into the second cap 71B.

[0028] The wiping device 75 wipes the nozzle surfaces 41S of the first ink head 41 and 42S of the second ink head 42 and forms a meniscus at the nozzles 44. As shown in FIG. 2, the wiping device 75 includes a wiper 76 that wipes the nozzle surfaces 41S and 42S, and a wiper moving device 77 (see FIG. 6) that moves the wiper 76.

[0029] The ink supply system 80 supplies the ink stored in the ink cartridge 61 to the recording head 40. As shown in FIG. 4, the ink supply system 80 includes a first system 80A that connects the ink cartridge 61A and the nozzle row 43A of the first ink head 41, a second system 80B that connects the ink cartridge 61B and the nozzle row 43B of the first ink head 41, a third system 80C that connects the ink cartridge 61C and the nozzle row 43C of the first ink head 41, a fourth system 80D that connects the ink cartridge 61D and the nozzle row 43D of the first ink head 41, a fifth system 80E that connects the ink cartridge 61E and the nozzle row 43E of the second ink head 42, a sixth system 80F that connects the ink cartridge 61F and the nozzle row 43F of the second ink head 42, a seventh system 80G that connects the ink cartridge 61G and the nozzle row 43G of the second ink head 42, and an eighth system 80H that connects the ink cartridge 61H and the nozzle row 43H of the second ink head 42. Here, the plurality of systems 80A to 80H have the same configuration.

[0030] Hereinafter, the configuration of the first system 80A will be described. Since the other systems 80B to 80H are configured in the same manner as the first system 80A, detailed description and illustration thereof will be omitted.

[0031] As shown in FIG. 4, the first system 80A includes an ink flow path 81, a valve 82, a liquid feed pump 83, a decompression pump 84, and a damper 85. The ink flow path 81 connects the ink cartridge 61 and the ink head 41 and communicates the ink cartridge 61 with the plurality of nozzles 44. 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 the 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 the ink in the direction from the ink head 41 toward the ink cartridge 61. The decompression pump 84 is a pump that returns the ink toward the ink cartridge 61. The damper 85 is an intermediate container that stores the ink and alleviates the pressure fluctuation of the ink.

[0032] As shown in FIG. 4, the ink flow path 81 includes an upstream common flow path 81a, a first flow path 81b and a second flow path 81c branched 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 formed of flexible tubes. However, these flow paths are not limited to tubes and may be formed of, for example, fixed pipes.

[0033] As shown in FIG. 4, 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 end of the first flow path 81b and the upstream end of 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.

[0034] The downstream end of the first flow path 81b and the downstream end of the second flow path 81c are connected to the second branch portion 81f. The upstream end of the downstream common flow path 81d is also 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 a damper 85. The downstream common flow path 81d communicates with the ink head 41 via the damper 85.

[0035] The liquid delivery pump 83 is a pump capable of opening / closing the flow path and driving / stopping. In the present embodiment, the liquid delivery pump 83 is a tube pump. FIG. 5 is a schematic cross-sectional view of the liquid delivery pump 83. As shown in FIG. 5, the liquid delivery pump 83 includes an internal flow path 83a, a pair of rollers 83b, a pump wheel 83c, a motor 83d, and a pair of guide members 83e.

[0036] The internal flow path 83a is composed of a flexible tube. The internal flow path 83a is a member through which the ink passes. Both ends of the internal flow path 83a are connected to the first flow path 81b. The liquid delivery pump 83 sends out the ink by squeezing the internal flow path 83a with a pair of rollers 83b. The pair of rollers 83b is an example of a squeezing member for squeezing the internal flow path 83a.

[0037] The pump wheel 83c is configured in a disc shape. As shown in FIG. 5, the pair of rollers 83b is supported by the pump wheel 83c. The pump wheel 83c has a pair of roller support grooves 83c1 formed along its circumferential direction. Each roller support groove 83c1 is provided inclined with respect to the outer peripheral surface of the pump wheel 83c so as to be farther from the outer peripheral surface of the pump wheel 83c in the R1 direction along the circumferential direction of the pump wheel 83c. The pair of rollers 83b is respectively attached to one roller support groove 83c1. Each roller 83b is configured to be movable in the circumferential direction of the pump wheel 83c along the roller support groove 83c1. The internal flow path 83a is wound around the outside of the outer peripheral surface of the pump wheel 83c. The motor 83d rotates the pump wheel 83c in the R1 direction and the R2 direction, which is the reverse direction of the R1 direction. When the pump wheel 83c rotates in the R1 direction (hereinafter also referred to as the forward rotation direction R1, and the R2 direction is also referred to as the reverse rotation direction R2), the pair of rollers 83b revolves along the internal flow path 83a and squeezes the internal flow path 83a. The motor 83d is an example of a driving unit that runs a pair of rollers 83b as a squeezing member along the internal flow path 83a.

[0038] The liquid delivery pump 83 is configured to be switchable between an open state in which the internal flow path 83a is open and a closed state in which the internal flow path 83a is closed by the roller 83b. The pair of guide members 83e are arranged so as to overlap the turning orbit of the roller 83b. The pair of guide members 83e are formed of an elastic material and have flexibility. The guide member 83e crushes the internal flow path 83a by the pair of rollers 83b, or separates the pair of rollers 83b from the internal flow path 83a. When the pump wheel 83c rotates in the forward rotation direction R1, the roller 83b receives a force to be pushed back by the guide member 83e made of an elastic material. As a result, the roller 83b moves to the rear end in the traveling direction of the roller support groove 83c1. As a result, the roller 83b moves radially outward of the pump wheel 83c along the inclination of the roller support groove 83c1, and closes the internal flow path 83a. The liquid delivery pump 83 is configured to send ink by driving the motor 83d in the forward rotation direction R1 in the closed state.

[0039] Even when the pump wheel 83c is rotated in the reverse rotation direction R2, the roller 83b receives the force from the guide member 83e and moves to the rear end in the traveling direction of the roller support groove 83c1. When the pump wheel 83c is rotated in the reverse rotation direction R2, the roller 83b moves radially inward of the pump wheel 83c along the inclination of the roller support groove 83c1 and separates from the internal flow path 83a. As a result, the internal flow path 83a is opened. The liquid delivery pump 83 is configured to separate the pair of rollers 83b from the internal flow path 83a by reversely rotating the motor 83d.

[0040] The liquid delivery pump 83 is configured to be able to open, close, and send ink through the internal flow path 83a. "Stopping the liquid delivery pump 83" means not driving the motor 83d after closing the internal flow path 83a, which is the same as closing the internal flow path 83a here.

[0041] In this embodiment, the liquid feed pump 83 is configured such that it cannot send ink in the reverse direction. Further, the liquid feed pump 83 causes the roller 83b to run by the motor 83d (here, run in the forward rotation direction R1), whereby the internal flow path 83a switches from the open state in which it is open to the closed state in which the internal flow path 83a is closed by the roller 83b. Since the current position of the roller 83b is not sensed, when closing the internal flow path 83a, the roller 83b is run one full turn along the internal flow path 83a. Therefore, when the liquid feed pump 83 is switched from the open state to the closed state, ink for one full turn of the internal flow path 83a is sent.

[0042] In this embodiment, the pressure reducing pump 84 is also configured in the same manner as the liquid feed pump 83. The pressure reducing pump 84 is also configured such that the opening / closing of the flow path and the driving / stopping are possible. The pressure reducing pump 84 is also configured such that when switched from the open state to the closed state, ink for one full turn of the internal flow path is sent. When the pressure reducing pump 84 is switched from the open state to the closed state, it sends ink in the direction from the ink head 41 toward the ink cartridge 61. As shown by the reference numerals in parentheses in FIG. 5, the pressure reducing pump 84 includes an internal flow path 84a similar to that of the liquid feed pump 83, a pair of rollers 84b, a pump wheel 84c in which a pair of roller support grooves 84c1 are formed, a motor 84d, and a pair of guide members 84e. Note that the liquid feed pump 83 and the pressure reducing pump 84 are not limited to tube pumps. The liquid feed pump 83 and the pressure reducing pump 84 may have different configurations.

[0043] The closing of the liquid feed pump 83 may fail. In that case, the liquid feed pump 83 is not completely closed, and ink leaks through the portion of the internal flow path 83a crushed by the roller 83b. Similarly, the closing of the pressure reducing pump 84 may fail. In that case, the pressure reducing pump 84 is not completely closed, and ink leaks through the portion of the internal flow path 84a crushed by the roller 84b.

[0044] The damper 85 is an intermediate container that mitigates the pressure fluctuations of the ink. The damper 85 communicates with the ink head 41. The damper 85 is configured to store ink. As shown in FIG. 4, the damper 85 includes a storage chamber 85a and a pressure sensor 85b. An inlet and an outlet (not shown) are formed in the storage chamber 85a. Ink flows into the storage chamber 85a through the inlet and out of the storage chamber 85a through the outlet. Ink is temporarily stored in the storage chamber 85a.

[0045] The pressure sensor 85b is an example of a pressure detection device that detects the pressure within a portion of the ink flow path 81 on the ink head 41 side of the liquid feed pump 83. Here, the pressure sensor 85b measures the pressure of the ink within the storage chamber 85a. In the present embodiment, the pressure sensor 85b is a sensor that continuously measures the pressure of the ink. The pressure sensor 85b is, for example, a pressure sensor that utilizes the piezoelectric effect of a piezo element. The pressure sensor 85b is configured here to output a current or voltage (hereinafter also referred to as a signal) corresponding to the measured pressure of the ink. The control device 100 acquires the signal output by the pressure sensor 85b at each predetermined sampling period. The control device 100 thereby acquires the pressure of the ink within the damper 85.

[0046] When the pressure of the ink within the storage chamber 85a falls below the pressure P1 due to the consumption of the ink, the control device 100 is configured to drive the liquid feed pump 83. Hereinafter, the pressure P1 is also referred to as the liquid feed start pressure P1 (see FIG. 8). Further, when the pressure of the ink within the storage chamber 85a becomes equal to or greater than the pressure P2 due to the supply of ink by the liquid feed pump 83, the control device 100 stops the liquid feed pump 83. Hereinafter, the pressure P2 is also referred to as the liquid feed stop pressure P2 (see FIG. 8). The liquid feed stop pressure P2 is set to be greater than the liquid feed start pressure P1.

[0047] However, the signal transmitted by the pressure sensor 85b is not limited to the signals as described above. For example, the pressure sensor 85b may be configured to transmit a liquid feeding start signal when the pressure of the ink in the storage chamber 85a is lower than the liquid feeding start pressure P1, and transmit a liquid feeding stop signal when the pressure of the ink in the storage chamber 85a exceeds the liquid feeding stop pressure P2.

[0048] The mechanism for detecting the pressure of the ink in the storage chamber 85a is not limited to something like the pressure sensor 85b. For example, the damper 85 may include a damper film that forms a part of the wall surface of the storage chamber 85a and expands and contracts according to the pressure in the storage chamber 85a, and a sensor for detecting the position of the damper film. Based on the detected position of the damper film, the sensor may detect that the pressure of the ink in the storage chamber 85a is lower than the liquid feeding start pressure P1 and transmit a liquid feeding start signal, or based on the detected position of the damper film, detect that the pressure of the ink in the storage chamber 85a has reached the liquid feeding stop pressure P2 and transmit a liquid feeding stop signal.

[0049] The ink supply system 80 supplies ink to the ink head 41 while repeatedly driving and stopping the liquid feeding 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 44 in the normal state.

[0050] FIG. 6 is a block diagram of the printer 10. As shown in FIG. 6, the control device 100 is electrically connected to the front-back direction moving device 26 and the up-down direction moving device 27 of the bed moving device 25, the carriage motor 38 of the carriage moving device 35, the first ink head 41 and the second ink head 42, the light irradiation device 50, the cap moving device 72 of the capping device 70, the first suction pump 73A, and the second suction pump 73B, and the wiper moving device 77 of the wiping device 75, and the valve 82, the liquid feed pump 83, and the decompression pump 84 (only one is shown in FIG. 6) of the ink supply system 80, and controls their operations. Further, the control device 100 is electrically connected to the pressure sensor 85b (only one is shown in FIG. 6) of the damper 85 and receives a signal transmitted by the pressure sensor 85b. The control device 100 is, for example, a microcomputer and may include a central processing unit (hereinafter referred to as CPU), a ROM in which programs executed by the CPU and the like are stored, and a RAM. Each part of the control device 100 may be configured by software or by hardware. Further, each part may be a processor or a circuit. The configuration of the control device 100 is not particularly limited.

[0051] As shown in FIG. 6, the control device 100 includes a supply control unit 110, a purge control unit 120, a closing unit 130, a decompression control unit 140, a determination unit 150, a retry command unit 160, a warning unit 170, and a suction control unit 180 as control units for controlling the ink supply system 80 and the capping device 70. Note that the control device 100 may include, for example, a control unit for controlling other operations such as a printing operation, another control unit for controlling the ink supply system 80, another control unit for controlling the capping device 70, etc., but the description and illustration are omitted here.

[0052] 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 ink is consumed and the pressure measured by the pressure sensor 85b drops below the liquid supply start pressure P1, the supply control unit 110 drives the liquid supply pump 83. When ink is supplied to the damper 85 and the pressure measured by the pressure sensor 85b reaches the liquid supply stop pressure P2, the supply control unit 110 stops the liquid supply pump 83. The supply control unit 110 includes first to eighth supply control units that control the operations of the first to eighth systems 80A to 80H, respectively (illustrations are omitted).

[0053] The purge control unit 120 controls the operation of pressure cleaning, which pressurizes the ink by sending the ink with the liquid supply pump 83 and discharges the ink from the nozzles 44. In pressure cleaning, the purge control unit 120 drives the liquid supply pump 83 to discharge the ink from the nozzles 44. After pressurizing the ink, the purge control unit 120 drives the decompression pump 84 to lower the ink pressure in the ink flow path 81 to a printable pressure (a negative pressure at which a meniscus is formed at the nozzles 44). The decompression pump 84 is a pump for returning the ink pressure in the ink flow path 81 to a printable pressure after pressure cleaning. The purge control unit 120 includes first to eighth purge control units that control the operations of the first to eighth systems 80A to 80H, respectively (illustrations are omitted).

[0054] When starting the use of the printer 10 or the like, the control device 100 includes a control unit for closing the liquid supply pump 83 and the decompression pump 84, and related control units. The liquid supply pump 83 is open before use to prevent the internal flow path 83a from being irreversibly collapsed. The same applies to the decompression pump 84. As control units related to the closing of the liquid supply pump 83 and the decompression pump 84 (hereinafter also referred to as initial closing) when starting the use of the printer 10 or the like, the control device 100 includes a closing unit 130, a decompression control unit 140, a determination unit 150, a retry command unit 160, a warning unit 170, and a suction control unit 180.

[0055] As shown in FIG. 6, the closing unit 130 includes a liquid feeding control unit 131 and a closing control unit 132. The liquid feeding control unit 131 drives the liquid feeding pump 83 to feed ink during initial closing. Specifically, the liquid feeding control unit 131 closes the internal flow path 83a by the roller 83b and drives the motor 83d to feed ink. The closing control unit 132 closes the pressure reducing pump 84 before the liquid feeding pump 83 starts feeding ink under the control of the liquid feeding control unit 131. During initial closing, the liquid feeding control unit 131 drives the liquid feeding pump 83 to feed ink with the pressure reducing pump 84 closed. Although not shown, the closing unit 130 includes first to eighth closing units that control the operations of the first to eighth systems 80A to 80H, respectively.

[0056] The pressure reducing control unit 140 drives the capping device 70 during initial closing. "Driving the capping device 70" here means attaching the first cap 71A to the first ink head 41, attaching the second cap 71B to the second ink head 42, and driving the first suction pump 73A and the second suction pump 73B. The pressure reducing control unit 140 drives the capping device 70 during initial closing to suck ink from the nozzles 44 and reduce the pressure in the ink flow path 81. The capping device 70 is also an example of a pressure reducing device that reduces the pressure in a plurality of nozzles 44 and discharges the ink in the ink flow path 81 from the plurality of nozzles 44. The pressure reducing control unit 140 drives the capping device 70 when the pressure reducing pump 84 is closed under the control of the closing control unit 132. Also, the pressure reducing control unit 140 drives the capping device 70 even when the liquid feeding pump 83 is being driven under the control of the liquid feeding control unit 131. The liquid feeding control unit 131 feeds ink with the capping device 70 being driven under the control of the pressure reducing control unit 140. In the present embodiment, the pressure reducing control unit 140 is configured to drive the capping device 70 from before the pressure reducing pump 84 is closed under the control of the closing control unit 132 until the driving of the liquid feeding pump 83 under the control of the liquid feeding control unit 131 ends.

[0057] As shown in FIG. 6, the pressure reduction control unit 140 includes a mounting control unit 141, a first pressure reduction control unit 142, and a second pressure reduction control unit 143. The mounting control unit 141 drives the cap moving device 72 to mount the first cap 71A on the first ink head 41 and the second cap 71B on the second ink head 42. The mounting control unit 141 drives the cap moving device 72 to mount the first cap 71A on the first ink head 41 and the second cap 71B on the second ink head 42 before the liquid sending pumps 83 of the respective systems 80A to 80H send ink under the control of the liquid sending control units 131 of the respective systems 80A to 80H. The first pressure reduction control unit 142 drives the first suction pump 73A. The second pressure reduction control unit 143 drives the second suction pump 73B.

[0058] The determination unit 150 determines whether the liquid sending pump 83 and the pressure reduction pump 84 are closed. Specifically, the determination unit 150 determines that the liquid sending pump 83 and the pressure reduction pump 84 are closed when the pressure detected by the pressure sensor 85b reaches a predetermined determination pressure P2 (see FIG. 8) before a predetermined time T1 (see FIG. 8) elapses after the liquid sending control unit 131 starts sending ink. The determination unit 150 determines that at least one of the liquid sending pump 83 and the pressure reduction pump 84 is not closed when the pressure detected by the pressure sensor 85b does not reach the determination pressure P2 even after the predetermined time T1 elapses after the liquid sending control unit 131 starts sending ink. In the present embodiment, the determination pressure P2 is set to a pressure equal to the liquid sending stop pressure P2. However, the determination pressure may be set to a pressure different from the liquid sending stop pressure P2.

[0059] In this embodiment, the capping device 70 is driven before the liquid feed pump 83 is driven. Here, when the pressure of the ink in the damper 85 reaches the liquid feed start pressure P1 due to the pressure reduction of the capping device 70, the liquid feed control unit 131 drives the liquid feed pump 83. The liquid feed control unit 131 starts feeding the ink in a state where the pressure detected by the pressure sensor 85b is the liquid feed start pressure P1, which is lower than the determination pressure P2 (here, equal to the liquid feed stop pressure P2). Although not shown in the figure, the determination unit 150 includes first to eighth determination units that perform closing determination on the first to eighth systems 80A to 80H, respectively.

[0060] When the pressure detected by the pressure sensor 85b is lower than the determination pressure P2 even after a predetermined time T1 has elapsed since the liquid feed control unit 131 started feeding the ink, the retry command unit 160 issues a command to retry closing the decompression pump 84 and closing and driving the liquid feed pump 83. When the pressure detected by the pressure sensor 85b is lower than the determination pressure P2 even after a predetermined time T1 has elapsed since the liquid feed control unit 131 started feeding the ink, the determination unit 150 determines that at least one of the liquid feed pump 83 and the decompression pump 84 is not closed. The determination unit 150 does not determine which of the liquid feed pump 83 and the decompression pump 84 is not closed. Therefore, in such a case, the retry command unit 160 issues a command to retry closing the decompression pump 84 and closing and driving the liquid feed pump 83. Closing the decompression pump 84 may succeed by retrying. Closing the liquid feed pump 83 may also succeed by retrying. The retry command unit 160 includes first to eighth retry command units that issue retry commands based on the closing determination of the first to eighth systems 80A to 80H, respectively.

[0061] The warning unit 170 is configured to issue a warning when the number of times the retry command is issued reaches a predetermined number in each of the systems 80A to 80H. The warning unit 170 issues a warning regarding the system in which the number of times the retry command is issued has reached the predetermined number.

[0062] When a retry command is issued for at least one of the liquid feed pumps 83 and the pressure reducing pumps 84 in the lines 80A to 80D connected to the first ink head 41, and no retry command is issued for any of the liquid feed pumps 83 and the pressure reducing pumps 84 in the lines 80E to 80H connected to the second ink head 42, the second suction pump 73B is driven during at least the drive of the liquid feed pump 83 that has received the retry command and the retry of closing the pressure reducing pump 84. Similarly, when a retry command is issued for at least one of the lines 80E to 80H connected to the second ink head 42 and no retry command is issued for any of the lines 80A to 80D connected to the first ink head 41, the first suction pump 73A is driven during the retry of at least the line that has received the retry command. That is, while a retry is being performed in any one of the lines of the first ink head 41 and the second ink head 42, the inside of the cap attached to the ink head that is not connected to the line in which the retry is being performed is depressurized. Here, the suction control unit 180 drives the first suction pump 73A or the second suction pump 73B at a slower speed than at the time of initial closing.

[0063] [Process of Initial Closing] Hereinafter, the process of initial closing will be described. FIG. 7 is a flowchart of the initial closing of the liquid feed pump 83 and the pressure reducing pump 84. As shown in FIG. 7, in step S01 of the initial closing, the cap moving device 72 is driven, and the first cap 71A is attached to the first ink head 41 and the second cap 71B is attached to the second ink head 42. In step S02, the valves 82 of the respective lines 80A to 80H are opened. In step S03, the first suction pump 73A and the second suction pump 73B are driven. Thereby, ink is sucked from the nozzles 44A to 44D of the first ink head 41 and the nozzles 44E to 44H of the second ink head 42.

[0064] In the subsequent step S04, each pressure reducing pump 84 is closed. When the pressure reducing pump 84 is closed, the ink for one round of the internal flow path 84a is sent toward the ink cartridge 61. If the first suction pump 73A and the second suction pump 73B are not driven in step S04, the downstream side of the pressure reducing pump 84 in the ink flow path 81 becomes negative pressure due to the movement of this ink, and there is a risk that external foreign matter (for example, the ink remaining in the caps 71A and 71B) is sucked into the nozzle 44. In the present embodiment, this is prevented by driving the first suction pump 73A and the second suction pump 73B before closing each pressure reducing pump 84.

[0065] In step S05, the liquid feeding pump 83 is closed. Step S05 may be performed before steps S01 to S04 or during steps S01 to S04.

[0066] In step S06, in each system 80A to 80H, it is confirmed whether the pressure of the ink in the damper 85 has become less than the liquid feeding start pressure P1. In each system 80A to 80H, when the pressure detected by the pressure sensor 85b is equal to or higher than the liquid feeding start pressure P1 (when the result of step S06 is NO), the state up to step S05 is maintained. When the pressure detected by the pressure sensor 85b becomes less than the liquid feeding start pressure P1 (when the result of step S06 becomes YES), in step S07, the liquid feeding pump 83 is driven.

[0067] FIG. 8 is a graph showing the change in pressure within damper 85. In the state after step S05, as shown in section A of FIG. 8, due to the driving of the first suction pump 73A or the second suction pump 73B, the ink within damper 85 decreases, and the pressure within damper 85 also decreases. When the pressure within damper 85 falls below the liquid feeding start pressure P1, the liquid feeding pump 83 is driven in step S07. When the closing of the liquid feeding pump 83 and the decompression pump 84 is carried out normally, when the liquid feeding pump 83 is driven, as indicated by the solid line G1 in section B of FIG. 8, the pressure within damper 85 turns to increase. When the closing of the liquid feeding pump 83 is not carried out normally, compared with the case where the liquid feeding pump 83 is normally closed, the liquid feeding amount of the liquid feeding pump 83 decreases. Therefore, the pressure within damper 85 either rises more slowly or continues to decrease compared with the case where the liquid feeding pump 83 is normally closed. When the closing of the decompression pump 84 is not carried out normally, a part of the ink sent by the liquid feeding pump 83 circulates within the circulation flow path formed by the first flow path 81b and the second flow path 81c (see FIG. 4). Therefore, the pressure within damper 85 either rises more slowly or continues to decrease compared with the case where the liquid feeding pump 83 is normally closed. The broken line G2 shown in section B of FIG. 8 shows an example of the pressure change within damper 85 when at least one of the closing of the liquid feeding pump 83 and the closing of the decompression pump 84 fails.

[0068] In step S08, in each system 80A to 80H, it is confirmed whether the pressure within damper 85 has reached the determination pressure P2. When the pressure detected by the pressure sensor 85b is equal to or higher than the determination pressure P2 (when the result of step S08 is YES), in step S09, it is determined that the liquid feeding pump 83 and the decompression pump 84 are normally closed. In step S10, in response to the pressure within damper 85 reaching the liquid feeding stop pressure (determination pressure) P2, the liquid feeding pump 83 is stopped.

[0069] If the pressure detected by the pressure sensor 85b in step S08 has not reached the determination pressure P2 (if the result of step S08 is NO), in step S11, it is determined whether a predetermined time T1 has elapsed since the start of driving of the liquid feed pump 83. If the predetermined time T1 has not elapsed since the start of driving of the liquid feed pump 83 (if the result of step S11 is NO), the determination in step S08 is performed again. If the predetermined time T1 has elapsed since the start of driving of the liquid feed pump 83 (if the result of step S11 is YES), in step S12, it is determined that at least one of the liquid feed pump 83 and the decompression pump 84 has failed to close. In step S13, the liquid feed pump 83 is stopped. In step S14 following step S13, the closing and driving of the liquid feed pump 83 and the closing of the decompression pump 84 are retried.

[0070] FIG. 9 is a flowchart showing the flow of the retry of the initial closing (step S14). Note that FIG. 9 also includes the processing when no retry is required for all the lines 80A to 80H for convenience of explanation. As shown in FIG. 9, in step S21 of the retry, it is determined whether there is a line that requires a retry among the lines 80A to 80D connected to the first ink head 41. In step S22, it is determined whether there is a line that requires a retry among the lines 80E to 80H connected to the second ink head 42. By steps S21 and S22, (1) when there is no line that requires a retry among the lines 80A to 80D connected to the first ink head 41 and also among the lines 80E to 80H connected to the second ink head 42, (2) when there is a line that requires a retry among the lines 80A to 80D connected to the first ink head 41 and there is no line that requires a retry among the lines 80E to 80H connected to the second ink head 42, (3) when there is no line that requires a retry among the lines 80A to 80D connected to the first ink head 41 and there is a line that requires a retry among the lines 80E to 80H connected to the second ink head 42, (4) when there is a line that requires a retry among the lines 80A to 80D connected to the first ink head 41 and also among the lines 80E to 80H connected to the second ink head 42, the processing branches.

[0071] (1) In this case, since no retry is required for all the lines 80A to 80H, in step S31, the first suction pump 73A and the second suction pump 73B are stopped. In step S32, the cap moving device 72 is controlled to separate the first cap 71A and the second cap 71B from the first ink head 41 and the second ink head 42, respectively. In step S33, the nozzle surfaces 41S of the first ink head 41 and 42S of the second ink head 42 are wiped by the wiping device 75. Thereby, a meniscus is formed on the nozzle 44.

[0072] In the case of (2), since a retry is necessary in at least one of the systems 80A to 80H connected to the first ink head 41, in step S41, it is determined to continue attaching the first cap 71A and the second cap 71B to the first ink head 41 and the second ink head 42, respectively (continuation of attachment determination). In the present embodiment, since the cap moving device 72 is common to the first ink head 41 and the second ink head 42, it is not possible to only separate the second cap 71B from the second ink head 42. In step S42, it is determined to continue driving the first suction pump 73A (continuation of suction determination).

[0073] Step S43 regarding the retry is the same as steps S04 to S11, so the details are omitted. In step S44 after the retry, it is determined whether the closing of the liquid supply pump 83 and the decompression pump 84 was successful. If the closing of the liquid supply pump 83 and the decompression pump 84 was successful (when the result of step S44 is YES), for the system that was retried, the process of initial closing ends. If the closing of the liquid supply pump 83 and the decompression pump 84 fails (when the result of step S44 is NO), in step S45, it is determined whether the number of failures has reached a predetermined number. If the number of failures has not reached the predetermined number (when the result of step S45 is NO), in step S43, the initial closing of the liquid supply pump 83 and the decompression pump 84 is retried again. If the number of failures has reached the predetermined number (when the result of step S45 is YES), a warning is issued in step S46. With the warning, the user of the printer 10 can know that there is a problem with at least one of the liquid supply pump 83 and the decompression pump 84.

[0074] On the other hand, regarding the second ink head 42, no retry is required in all the connected systems 80E to 80H. In the present embodiment, for an ink head that does not require retry in all the connected systems, suction is performed with the cap attached. In the case of (2), in step S42, while retrying the system that has received the retry command, the second suction pump 73B is driven. By such suction, the ink accumulated in the second cap 71B is prevented from being sucked into the nozzle 44. The ink accumulated in the second cap 71B is, here, a mixed-color ink in which a plurality of types of inks are mixed, and it is not preferable for it to return to the nozzle 44. In the present embodiment, the second suction pump 73B is driven at a speed slower than when it is initially closed. Thereby, the amount of ink sucked and discarded by the second suction pump 73B is reduced. The processing after the retry of all the systems is completed is the same as that in steps S31 to S33, and thus the description thereof is omitted.

[0075] In the case of (3), the first ink head 41 and the second ink head 42 are reversed compared to the case of (2). The details of the case of (3) are omitted. In the case of (4), retry is performed in both the systems connected to the first ink head 41 and the systems connected to the second ink head 42. When the retry is completed in all the systems connected to one of the ink heads 41 or 42 and the retry is still being performed in the other, suction similar to step S42 is performed on the ink head in which the retry has been completed in all the connected systems.

[0076] [Operation and Effect of Embodiment] Hereinafter, the operation and effect that the printer 10 according to the present embodiment can exhibit will be described.

[0077] The printer 10 according to this embodiment includes an ink cartridge 61 containing ink, an ink head 41 having a plurality of nozzles 44 from which ink is ejected, an ink flow path 81 connecting the ink cartridge 61 and the ink head 41 and communicating the ink cartridge 61 with the plurality of nozzles 44, a liquid feed pump 83 provided in the ink flow path 81 and sending ink in a direction from the ink cartridge 61 toward the ink head 41, a pressure sensor 85b detecting the pressure in a portion of the ink flow path 81 on the ink head 41 side of the liquid feed pump 83, and a control device 100 controlling the liquid feed pump 83. The liquid feed pump 83 includes an internal flow path 83a, a roller 83b squeezing the internal flow path 83a, and a motor 83d running the roller 83b along the internal flow path 83a. The liquid feed pump 83 is configured to be switchable between an open state in which the internal flow path 83a is open and a closed state in which the internal flow path 83a is closed by the roller 83b. The liquid feed pump 83 is configured to send ink by driving the motor 83d in the closed state. The control device 100 includes a liquid feed control unit 131 closing the internal flow path 83a by the roller 83b and driving the motor 83d to send ink, and a determination unit 150 determining that the liquid feed pump 83 is closed when the pressure detected by the pressure sensor 85b reaches a predetermined determination pressure P2 before a predetermined time T1 elapses after the liquid feed control unit 131 starts sending ink.

[0078] According to such a printer 10, the liquid feed pump 83 sends ink by running the roller 83b with the internal flow path 83a closed by the roller 83b. Therefore, if the closing of the internal flow path 83a by the roller 83b is insufficient, the ink feed amount decreases. As a result, even when a predetermined time T1 elapses after starting to send ink, the pressure detected by the pressure sensor 85b remains below the predetermined determination pressure P2. The printer 10 determines that the liquid feed pump 83 has been normally closed when the pressure detected by the pressure sensor 85b reaches the predetermined determination pressure P2 before a predetermined time T1 elapses after starting to send ink.

[0079] According to the printer 10 according to the present embodiment, it is possible to confirm the closing of the liquid feed pump 83 without using the head pressure of the ink applied to the liquid feed pump 83. In the present embodiment, the ink cartridge 61 is disposed at substantially the same vertical position as the first ink head 41 and the second ink head 42. Therefore, although the head pressure of the ink cannot be used to confirm the closing of the liquid feed pump 83, the closing of the liquid feed pump 83 is confirmed by driving the liquid feed pump 83. By not using the head pressure of the ink to confirm the closing of the liquid feed pump 83, freedom in arranging the ink cartridge 61 and the ink heads 41 and 42 is created. In a conventional method that uses the head pressure of the ink to confirm the closing of the liquid feed pump, the liquid feed pump is closed and it is confirmed that the pressure in the damper does not rise. If the liquid feed pump cannot be closed, ink leaks from the liquid feed pump due to the head pressure and the pressure in the damper rises.

[0080] However, the printer 10 may be configured to use the head pressure of the ink as well as driving the liquid feed pump 83 to confirm the closing of the liquid feed pump 83.

[0081] In the present embodiment, the liquid feed control unit 131 is configured to start feeding the ink in a state where the pressure detected by the pressure sensor 85b is a predetermined pressure (here, the liquid feed start pressure P1) smaller than the determination pressure P2. According to such a configuration, after adjusting the pressure of the ink to a predetermined pressure P1 smaller than the determination pressure P2, the ink feeding by the liquid feed pump 83 is started. Therefore, the time until the ink pressure reaches the determination pressure P2 when the liquid feed pump 83 is normally closed is always substantially the same. Thus, it is possible to more reliably confirm the closing of the liquid feed pump 83.

[0082] The printer 10 according to this embodiment includes a capping device 70 that reduces the pressure inside a plurality of nozzles 44 and discharges the ink in the ink flow path 81 from the plurality of nozzles 44. The control device 100 includes a pressure reduction control unit 140 that drives the capping device 70. The liquid supply control unit 131 is configured to send ink in a state where the capping device 70 is being driven under the control of the pressure reduction control unit 140. According to such a configuration, if the liquid supply pump 83 does not send ink, the pressure of the ink decreases due to the pressure reduction of the capping device 70. Therefore, it is possible to more reliably determine whether the liquid supply pump 83 is normally sending ink. In addition, since it is not necessary to set the determination pressure P2 to a high pressure, the burden on the damper 85 due to the ink pressure can be reduced.

[0083] The printer 10 according to this embodiment further includes a pressure reduction pump 84 provided in the ink flow path 81 and configured to send ink in a direction from the ink head 41 toward the ink cartridge 61. The ink flow path 81 includes a first flow path 81b provided with the liquid supply pump 83, a second flow path 81c provided with the pressure reduction pump 84, a first branch portion 81e connected to the upstream end of the first flow path 81b and the upstream end of the second flow path 81c and communicating with the ink cartridge 61, and a second branch portion 81f connected to the downstream end of the first flow path 81b and the downstream end of the second flow path 81c and communicating with the ink head 41. According to such a configuration, it is possible to perform pressurized cleaning of the nozzles 44 and subsequent pressure reduction in the ink flow path 81.

[0084] In this embodiment, before the liquid feeding pump 83 starts feeding ink under the control of the liquid feeding control unit 131, the control device 100 includes a closing control unit 132 that closes the decompression pump 84, and when the pressure detected by the pressure sensor 85b is lower than the determination pressure P2 even after a predetermined time T1 has elapsed since the liquid feeding control unit 131 starts feeding ink, a retry command unit 160 that issues a command to retry closing the decompression pump 84, closing and driving the liquid feeding pump 83. According to such a configuration, by closing the decompression pump 84, it is possible to confirm the closing of the liquid feeding pump 83 as described above, and it is also possible to confirm that the decompression pump 84 is closed. However, when the pressure detected by the pressure sensor 85b is lower than the determination pressure P2 even after a predetermined time T1 has elapsed since the liquid feeding control unit 131 starts feeding ink, it is impossible to distinguish whether the closing of the liquid feeding pump 83 has failed or the closing of the decompression pump 84 has failed. Therefore, in this embodiment, regardless of whether the closing of the liquid feeding pump 83 has failed or the closing of the decompression pump 84 has failed, a retry of closing the decompression pump 84, closing and driving the liquid feeding pump 83 is performed. By such a retry, in many cases, the liquid feeding pump 83 and the decompression pump 84 can be normally closed.

[0085] In this embodiment, the control device 100 includes a warning unit 170 that issues a warning when the number of times the retry command is issued reaches a predetermined number of times. According to such a configuration, it is possible to notify the user of the possibility that there is a problem with at least one of the liquid feeding pump 83 and the decompression pump 84.

[0086] In this embodiment, the vacuum pump 84 includes an internal flow path 84a, a roller 84b that squeezes the internal flow path 84a, and a motor 84d that causes the roller 84b to travel along the internal flow path 84a. The vacuum pump 84 is configured such that, by causing the roller 84b to travel by the motor 84d, the internal flow path 84a switches from an open state in which it is open to a closed state in which the internal flow path 84a is closed by the roller 84b. The vacuum pump 84 is configured to send ink by causing the roller 84b to travel in the closed state. The decompression control unit 140 drives the capping device 70 when closing the vacuum pump 84 under the control of the closing control unit 132. In such a configuration, when the vacuum pump 84 is closed, the ink is sent toward the ink cartridge 61 side. As a result, the downstream side of the vacuum pump 84 in the ink flow path 81 becomes negative pressure, and there is a risk that foreign matter from the outside is sucked in from the nozzles 44. In this embodiment, this is prevented by driving the first suction pump 73A and the second suction pump 73B before closing each vacuum pump 84.

[0087] In this embodiment, when a retry command is issued to at least one of the liquid feed pump 83 group and the vacuum pump 84 group connected to one of the ink heads 41 or 42, and no retry command is issued to any of the liquid feed pump 83 group and the vacuum pump 84 group connected to the other ink head 42 or 41, the control device 100 includes a suction control unit 180 that drives the suction pump 73B or 73A attached to the other ink head 42 or 41 at least during the retry of driving the liquid feed pump 83 that has received at least the retry command and closing the vacuum pump 84. According to such a configuration, while a retry is being performed with one of the ink heads 41 or 42, by sucking the other ink head 42 or 41, it is possible to suppress the ink in the cap 71B or 71A from being drawn into the nozzles 44 of the other ink head 42 or 41.

[0088] In this embodiment, the ink cartridges 61A to 61D connected to the first ink head 41 contain at least two different types of ink. The ink cartridges 61E to 61H connected to the second ink head 42 contain at least two different types of ink. With such a configuration, different types of ink are mixed inside the caps 71A and 71B. When this is sucked into the nozzles 44, there is a risk that color mixing may continue for a long time or suddenly occur, which is not preferable. According to the printer 10 according to this embodiment, by driving the capping device 70 to suppress the ink in the cap 71B or 71A from being drawn into the nozzles 44, such color mixing can be suppressed.

[0089] [Other Embodiments] As described above, a preferred embodiment has been explained. However, the printer of the present invention is not limited to the above-described embodiment. For example, the configuration of the ink supply system 80 is not limited to the above-described one. The ink supply system 80 may not include the decompression pump 84 and the second flow path 81c. Or, the ink supply system 80 may further include other pipes, other valves, etc. When the ink supply system 80 includes the decompression pump 84 and the second flow path 81c, the confirmation of the initial closure may be the same as the conventional method using the head pressure of the ink. For example, control to retry regardless of whether the liquid feed pump 83 or the decompression pump 84 has failed to close, control to drive the capping device 70 when closing the decompression pump 84, etc. may be combined with a method that uses the head pressure of the ink for the closure confirmation.

[0090] In the above-described embodiment, the cap moving device 72 of the capping device 70 was common to the plurality of caps 71A and 71B, but each cap may be movable independently.

[0091] 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 above-described printer 10 is merely illustrative and is not particularly limited.

[0092] In addition, unless otherwise specified, the embodiments do not limit the present invention.

Explanation of Reference Numerals

[0093] 10 Inkjet printer (printer) 41 First ink head (ink head) 42 Second ink head 44 Nozzle 61 Ink cartridge (ink container) 70 Capping device (pressure reducing device) 71A First cap 71B Second cap 72 Cap moving device (mounting device) 73A First suction pump (first suction device) 73B Second suction pump (second suction device) 80 Ink supply system 81 Ink flow path 81b First flow path 81c Second flow path 81e First branch portion 81f Second branch portion 83 Liquid feeding pump 83a Internal flow path 83b Roller (extrusion member) 83d Motor (driving portion) 84 Pressure reducing pump 84a Internal flow path 84b Roller (extrusion member) 84d Motor (driving portion) 85 Damper 85b Pressure sensor (pressure detection device) 100 Control device 131 Liquid feeding control portion 132 Closing control unit 140 Pressure reduction control unit 141 Mounting control unit 142 First pressure reduction control unit 143 Second pressure reduction control unit 150 Judgment unit 160 Retry instruction unit 170 Warning unit 180 Suction control unit P1 Liquid feeding start pressure (predetermined pressure) P2 Liquid feeding stop pressure (judgment pressure)

Claims

1. An ink container containing ink, an ink head having a plurality of nozzles from which ink is ejected, an ink flow path connecting the ink container and the ink head and communicating the ink container with the plurality of nozzles, a liquid feeding pump provided in the ink flow path for feeding ink in a direction from the ink container toward the ink head, a pressure detection device for detecting the pressure in a portion of the ink flow path on the ink head side of the liquid feeding pump, a control device for controlling the liquid feeding pump, and comprising: The liquid feeding pump comprises an internal flow path, a pressing member for squeezing the internal flow path, and a driving unit for running the pressing member along the internal flow path, and is configured to be switchable between an open state in which the internal flow path is open and a closed state in which the internal flow path is closed by the pressing member, is configured to feed ink by driving the driving unit in the closed state, The control device comprises a liquid feeding control unit for closing the internal flow path by the pressing member and driving the driving unit to feed ink, and a determination unit for determining that the liquid feeding pump is closed when the pressure detected by the pressure detection device reaches a predetermined determination pressure before a predetermined time has elapsed since the liquid feeding control unit starts feeding ink. A printer.

2. The liquid feeding control unit is configured to start feeding ink in a state where the pressure detected by the pressure detection device is a predetermined pressure lower than the determination pressure. The printer according to Claim 1.

3. Further comprising a decompression device for decompressing the inside of the plurality of nozzles and discharging the ink in the ink flow path from the plurality of nozzles, The control device comprises a decompression control unit for driving the decompression device, The liquid feeding control unit is configured to feed ink in a state where the decompression device is driven under the control of the decompression control unit. The printer according to Claim 1.

4. Further comprising a return pump provided in the ink flow path for feeding ink in a direction from the ink head toward the ink container, The ink flow path comprises a first flow path provided with the liquid feeding pump, a second flow path provided with the return pump, and 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 second branch portion connected to the other end of the first flow path and the other end of the second flow path and communicating with the ink head. The printer according to claim 1.

5. The control device A closing control unit that closes the return pump before the liquid feed pump starts feeding ink under the control of the liquid feed control unit; A retry command unit that issues a command to retry closing the return pump, closing and driving the liquid feed pump when the pressure detected by the pressure detection device is below the determination pressure even after the predetermined time has elapsed since the liquid feed control unit started feeding ink. The printer according to claim 4.

6. The control device includes a warning unit that issues a warning when the number of times the retry command is issued reaches a predetermined number of times. The printer according to claim 5.

7. Further comprising a pressure reducing device for reducing the pressure inside the plurality of nozzles, The return pump Comprises an internal flow path, an extrusion member that squeezes the internal flow path, and a drive unit that runs the extrusion member along the internal flow path, By running the extrusion member by the drive unit, it is configured to switch from an open state where the internal flow path is open to a closed state where the internal flow path is closed by the extrusion member, It is configured to send ink by running the extrusion member in the closed state, The control device includes a pressure reducing control unit that drives the pressure reducing device when closing the return pump under the control of the closing control unit. The printer according to claim 5.

8. Comprising a plurality of ink containers including the ink container, a first ink container group that stores ink respectively; Comprising a plurality of ink flow paths including the ink flow path, a first ink flow path group that connects each ink container of the first ink container group and the ink head; Comprising a plurality of liquid feed pumps including the liquid feed pump, a first liquid feed pump group provided in each ink flow path of the first ink flow path group; Comprising a plurality of pressure detection devices including the pressure detection device, a first pressure detection device group provided in each ink flow path of the first ink flow path group; A second ink head having a plurality of second nozzles from which ink is ejected; Comprising a plurality of ink containers, a second ink container group that stores ink respectively; It is composed of a plurality of ink flow paths, and a second ink flow path group that connects each ink container of the second ink container group and the second ink head. It is composed of a plurality of liquid feeding pumps, and a second liquid feeding pump group respectively provided in the ink flow paths of the second ink flow path group. It is composed of a plurality of pressure detection devices, and a second pressure detection device group respectively provided in the ink flow paths of the second ink flow path group. A first cap that can cover the plurality of nozzles of the ink head and accommodate ink, a second cap that can cover the plurality of second nozzles of the second ink head and accommodate ink, a mounting device that mounts the first cap on the ink head and the second cap on the second ink head, a first suction device that decompresses the inside of the first cap, and a second suction device that decompresses the inside of the second cap, and a decompression device having the same. The liquid feeding control unit is configured to control each liquid feeding pump of the first liquid feeding pump group and each liquid feeding pump of the second liquid feeding pump group to feed ink. The control device is Before each liquid feeding pump feeds ink under the control of the liquid feeding control unit, a mounting control unit that drives the mounting device to mount the first cap on the ink head and the second cap on the second ink head. A retry command unit that issues a command to restart the driving of a plurality of liquid feeding pumps of the first liquid feeding pump group and the second liquid feeding pump group when the pressure detected by the pressure detection device is lower than a predetermined determination pressure even after a predetermined time has elapsed since the liquid feeding control unit starts feeding ink. When a retry command is issued to at least one of the liquid feeding pumps of the first liquid feeding pump group and no retry command is issued to any of the liquid feeding pumps of the second liquid feeding pump group, a suction control unit that drives the second suction device during at least the restart of the driving of the liquid feeding pump that has received the retry command. The printer according to claim 1.

9. At least two different types of ink are accommodated in the second ink container group. The printer according to claim 8.

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