JP6112125B2 - Liquid ejector - Google Patents

Description

  The present invention relates to a liquid ejecting apparatus and a maintenance method for the liquid ejecting apparatus.

  As a liquid ejecting apparatus, an ink jet printer (hereinafter referred to as a printer) that ejects ink (liquid) to a recording medium from an ejection port (nozzle) of a recording head (liquid ejecting head) is known.

  Such a printer includes a tank for storing ink, supplies the ink in the tank to the recording head, and discharges the ink from the recording head. The ink usually comprises a dispersion liquid containing a solid content such as a pigment and a dispersion medium such as a solvent.

  When such ink is used in a printer, especially when the printer is turned off and kept in a non-use state, the solid content in the ink stored in the tank separates and settles (precipitates), thereby solidifying the ink. Partial concentration may be non-uniform. Then, when sedimentation of solid content and uneven solid content concentration occur in this way, when the power is turned off, the power is turned on again to eject ink, and when printing is performed, the solid content settled in the tank If the ink is supplied as it is to the ink jet head side, problems such as nozzle clogging of the recording head and unevenness in recording quality occur.

  Therefore, in order to prevent such inconvenience, a recording apparatus that provides two supply paths for communicating the tank for storing (accommodating) the ink and the recording head and circulates the ink between the recording head and the tank. (Printer) is known (see, for example, Patent Document 1).

JP 2007-33281 A

  However, in the above configuration, there is a possibility that gas flows from the ejection head by circulating the ink.

  In view of the circumstances as described above, it is an object of the present invention to provide a liquid ejecting apparatus and a maintenance method for the liquid ejecting apparatus that can suppress the inflow of gas from the ejecting head during a maintenance operation.

The liquid ejecting apparatus according to the invention includes a liquid ejecting head that ejects liquid supplied to the common liquid chamber from a plurality of nozzles, a first path for supplying the liquid to the common liquid chamber of the liquid ejecting head, A second path that is provided separately from the first path and forms a circulation path with the first path; and a valve that is provided in the first path and is capable of regulating the flow of the liquid in the first path. A liquid chamber having a flexible wall that can be bent and deformed on a side closer to the common liquid chamber than a communication portion that is blocked when the flow of the liquid is restricted, and the pressure in the liquid chamber becomes smaller than a predetermined pressure. When the flexible wall is bent in the direction in which the volume of the liquid chamber is reduced, the flow of the liquid is allowed, and the pressure is equal to or greater than the predetermined pressure, and the flexible wall is increased in the direction in which the volume of the liquid chamber is increased. And a valve that regulates the flow of the liquid when bent, and provided in the second path. A liquid drive unit capable of flowing the liquid in the circulation path, and driving the liquid drive unit so that the liquid in the circulation path flows in a direction to increase the volume of the liquid chamber. The flow of the liquid is regulated by the valve, and a discharge operation for discharging the liquid from the nozzle is performed.

According to the aspect of the invention, the liquid ejecting head is pressurized by the liquid flowing to the liquid ejecting head by driving the liquid driving unit. Thereby, since the liquid can be discharged from the nozzle, the ejection state of the nozzle can be maintained .

The liquid ejecting apparatus performs a circulation operation of circulating the liquid in the circulation path in a state where the valve allows the flow of the liquid when the liquid ejecting head does not eject the liquid onto the ejecting medium. The liquid driving unit is driven to perform the operation .
The liquid ejecting apparatus includes a cap portion that covers an ejection surface on which the nozzles of the liquid ejection head are formed, and performs the circulation operation in a state where the ejection surface is covered with the cap portion. .

The liquid ejecting apparatus is characterized in that, in the circulation operation, the liquid driving unit is driven so as to have a pressure that maintains a meniscus of the liquid in the nozzle.
According to the present invention, since the liquid is supplied by the liquid driving unit at a pressure that maintains the liquid meniscus in the nozzle, the liquid meniscus can be maintained even when the liquid supply speed is increased .
The liquid ejecting apparatus above SL communicates with the first path and the second path includes a liquid storage portion forming part of the circulation path, the liquid in the circulation path, in the second path The discharging operation is performed by flowing in a direction from the liquid reservoir to the liquid ejecting head .
The liquid ejecting apparatus above SL has a support surface for supporting the medium to be injected with the liquid, a conveying path which the medium is transported, the liquid ejecting head, the direction of gravity above the said support surface It is provided to be movable.
The liquid ejecting apparatus includes a cap portion that covers an ejecting surface on which the nozzle of the liquid ejecting head is formed, and the cap portion is disposed below the support surface when the liquid is ejected onto the medium. It is characterized by evacuating.
The liquid ejecting apparatus includes a liquid storage unit that communicates with the first path and the second path and forms a part of the circulation path, and includes the common liquid chamber, the first path, the second path, and A plurality of the liquid reservoirs are provided so that different liquids can be ejected from a plurality of precursor nozzles, and the plurality of liquid reservoirs are arranged in a direction in which the medium to which the liquid is ejected is conveyed. It is characterized by.
The liquid ejecting apparatus communicates with the first path and the second path, and supplies the liquid reservoir that forms part of the circulation path and the liquid stored in the liquid cartridge to the liquid reservoir. And a liquid supply path.

  A maintenance method of a liquid ejecting apparatus according to the invention includes a liquid ejecting head that ejects liquid from a plurality of nozzles, a liquid storing unit that stores the liquid, and the liquid that is supplied from the liquid storing unit to the liquid ejecting head. A first supply path and the first supply path are provided separately, a second supply path communicating the liquid ejecting head and the liquid reservoir, and a first supply path provided in the first supply path. A check valve that allows the flow of the liquid from the liquid reservoir to the liquid ejecting head in the path and restricts the flow of the liquid from the liquid ejecting head to the liquid reservoir, and the first supply path; And a liquid drive unit capable of flowing the liquid in the second path, wherein the liquid is the liquid storage part in the first supply path. A circulation operation for circulating the liquid between the liquid storage unit and the liquid jet head so as to flow in the direction of the liquid jet head and in the second path from the liquid jet head to the liquid storage unit. When the liquid ejecting head is not ejecting the liquid onto the ejecting medium, the liquid driving unit is driven.

  According to the present invention, the first supply path for supplying the liquid from the liquid reservoir to the liquid ejecting head, the second path for communicating the liquid ejecting head and the liquid reservoir, and the first supply path are provided, A check valve that allows the flow of liquid from the liquid reservoir to the liquid ejecting head in the supply path and restricts the flow of liquid from the liquid ejecting head to the liquid storing section; and the liquid in the first supply path and the second path Since the liquid drive unit is capable of flowing, when the liquid ejecting head is not ejecting the liquid onto the ejection medium, the liquid drive unit can be driven to perform a maintenance operation by a circulation operation.

In the maintenance method for the liquid ejecting apparatus, the liquid driving unit is driven to perform a discharging operation for discharging the liquid from the nozzle to the outside.
According to the aspect of the invention, the liquid ejecting head is pressurized by the liquid flowing to the liquid ejecting head by driving the liquid driving unit. Thereby, since the liquid can be discharged from the nozzle, the ejection state of the nozzle can be maintained.
In addition, the liquid driving unit may be driven so that the liquid flows in the second path from the liquid storage unit toward the liquid ejecting head to perform the discharging operation.

The maintenance method for the liquid ejecting apparatus includes a cap portion that can cover a surface side of the liquid ejecting head on which the nozzle is formed, and the cap covers the surface side on which the nozzle is formed. The circulation operation is performed, and the discharging operation is performed in a state where the cap does not cover the surface on which the nozzle is formed.
According to the present invention, it is possible to prevent air from flowing in from the nozzle in the circulation operation. In addition, it is possible to prevent ink from leaking from the nozzles. Moreover, the discharge operation of discharging the liquid from the nozzle can be performed by driving the liquid driving unit, and the ejection state of the nozzle can be maintained.

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1 is a schematic diagram illustrating a configuration of a printer device according to an embodiment of the present invention. FIG. 3 is a plan view of a main part around an ejection head. The top view which shows the nozzle opening formation surface of an ejection head. The figure which shows the cross-sectional structure of an ejection head. The schematic diagram which shows schematic structure of a maintenance mechanism. FIG. 2 is a block diagram illustrating a configuration of a printer device. FIG. 4 is a diagram illustrating an operation of a printer device. FIG. 4 is a diagram illustrating an operation of a printer device. FIG. 4 is a diagram illustrating an operation of a printer device. FIG. 6 is a schematic diagram illustrating another configuration of the printer device according to the invention.

  Hereinafter, embodiments of a liquid ejecting apparatus according to the invention will be described with reference to the drawings. In order to make each member of the liquid ejecting apparatus have a recognizable size, each member used in the following description shows each member with the scale appropriately changed. In the present embodiment, an ink jet printer apparatus will be described as an example of the liquid ejecting apparatus.

  FIG. 1 is a schematic configuration diagram of an ink jet printer (hereinafter, referred to as a printer device PRT) of the present embodiment. FIG. 2 is a plan view of a main part around the ejection head. FIG. 3 is a plan view showing a nozzle opening forming surface of the ejection head.

  In FIG. 1, an XYZ orthogonal coordinate system is set, and the positional relationship of each member may be described with reference to the XYZ orthogonal coordinate system. In this case, the transport direction of the recording medium M is the X direction (left and right direction in FIG. 1), the direction perpendicular to the nozzle formation region 15 of the ejection head 11 is the Z direction (up and down direction in FIG. 1), the X direction axis, and the Z direction axis. A direction perpendicular to the XZ plane formed by Y is defined as the Y direction (the depth direction in FIG. 1).

  As shown in these drawings, the printer device PRT is a device that records images, characters, and the like on a recording medium M. As the recording medium M, paper or plastic is used. The printer device PRT has an ink ejection mechanism IJ, a transport mechanism CR, a maintenance mechanism MN, and a control device CONT.

  The ink ejection mechanism IJ is a part that ejects ink droplets (liquid) onto the recording medium M. The ink ejecting mechanism IJ includes an ejecting head (liquid ejecting head) 11 and an ink supply unit 12. The ink used in the present embodiment uses a liquid in which dyes and pigments and a solvent for dissolving or dispersing them are basic components and various additives are added as necessary.

  The ejection head 11 is a head that can eject ink droplets of a plurality of colors onto the recording medium M. As shown in FIG. 2, the ejection head 11 is a line type having a nozzle forming region 15 over a length (maximum recording paper width W) exceeding at least one side of the maximum size recording medium M targeted by the printer apparatus PRT. It is an ejection head. The ejection head 11 is provided so as to be movable in the Z direction. The ejection head 11 has a nozzle 13 and a common ink chamber 14 shown in FIG.

  The common ink chamber 14 is one chamber (common ink chambers 14Y, 14M, 14C, and 14K) that respectively hold inks corresponding to, for example, four colors (yellow: Y, magenta: M, cyan: C, black: K). ). The nozzle formation area 15 is provided corresponding to the common ink chamber 14 of each color (nozzle formation areas 15Y, 15M, 15C, 15K).

  A plurality of nozzles 13 are provided in the nozzle formation regions 15Y, 15M, 15C, and 15K of the ejection head 11, and are openings that discharge the ink droplets of the four colors. Each of the plurality of nozzles 13 communicates with one common ink chamber 14. A plurality of nozzles 13 are arranged in the Y direction as shown in FIG. 3 (nozzle row L). One or a plurality of nozzle rows L are provided for the nozzle formation regions 15Y, 15M, 15C, and 15K of the respective colors. The number of nozzles 13 and the number of nozzle rows L are set as appropriate. A surface of the ejection head 11 on which the nozzles 13 are provided is an ejection surface 11A. The ejection surface 11 </ b> A is provided on the −Z side of the ejection head 11. The ejection head 11 ejects ink droplets toward the −Z side.

FIG. 4 is a cross-sectional view showing the configuration of the ejection head 11.
As shown in the figure, the ejection head 11 includes a head main body 18 and a flow path forming unit 22 connected to the head main body 18. The flow path forming unit 22 includes a vibration plate 19, a flow path substrate 20, and a nozzle substrate 21.

  The head main body 18 is provided with a plurality of piezoelectric elements 25, and each piezoelectric element 25 is provided corresponding to each of the plurality of nozzles 13.

  The flow path forming unit 22 includes a common ink chamber 14, an ink supply port 30 connected to the common ink chamber 14, and a pressure chamber 31 connected to the ink supply port 30. The pressure chamber 31 is provided corresponding to each nozzle 13. Each pressure chamber 31 is connected to the nozzle 13 at the end opposite to the common ink chamber 14.

  The nozzle substrate 21 has a plurality of nozzles 13 formed at a predetermined interval (pitch) in a predetermined direction. The outer surface of the nozzle substrate 21 is the ejection surface 11A.

  The ejection head 11 configured as described above is configured such that the piezoelectric element 25 expands and contracts when a drive signal is input to the piezoelectric element 25. The expansion and contraction of the piezoelectric element 25 is transmitted as a deformation of the diaphragm 19. Due to the deformation of the vibration plate 19, the volume of the pressure chamber 31 changes, and the pressure of the pressure chamber 31 containing ink fluctuates. Ink is ejected from the nozzle 13 due to the fluctuation of the pressure.

  The transport mechanism CR includes a paper feed roller 35, a discharge roller 36, and the like. The paper feed roller 35 and the discharge roller 36 are rotationally driven by a motor mechanism (not shown). The transport mechanism CR transports the recording medium M along the transport path MR in conjunction with the ink droplet ejecting operation by the ink ejecting mechanism IJ.

  Returning to FIG. 1, the ink supply unit (liquid storage unit) 12 is disposed on one side of the ink ejection mechanism IJ, and is connected to the common ink chambers 14 </ b> Y, 14 </ b> M, 14 </ b> C, and 14 </ b> K of the ejection head 11. The ink supply unit 12 includes ink tanks 12Y, 12M, 12C, and 12K that store the four colors of ink.

  The ink supply unit 12 is connected to the ejection head 11 via the first supply tube SR1 and the second supply tube SR2. The first supply tube SR <b> 1 is a path (first supply path) for supplying ink from the ink supply unit 12 to the ejection head 11. The first supply tube SR1 is provided with a valve unit VU. The second supply tube SR2 is a path (second supply path) that communicates the ink supply unit 12 and the ejection head 11. The second supply tube SR2 is provided with a supply pump (liquid driving unit) RP. Depending on the drive direction of the supply pump RP, a flow in the direction of supplying ink from the ink supply unit 12 to the ejection head 11 and a flow in the direction of supplying ink from the ejection head 11 to the ink supply unit 12 are generated. It has become.

FIG. 5 is a cross-sectional view schematically showing the configuration of the valve unit VU.
The ink storage chamber RM is formed inside the storage chamber forming member 50. The storage chamber forming member 50 has a partition 51 at the center in the left-right direction in the drawing. The ink storage chamber RM is divided into a first chamber (concave portion) R1 and a second chamber R2 by a partition 51. A communication part 52 is formed in the partition part 51. The first chamber R1 of the ink storage chamber RM is connected to the ink supply unit 12 via the first supply tube SR1. The second chamber R2 is connected to the ejection head 11 via the first supply tube SR1. The first chamber R <b> 1 and the second chamber R <b> 2 are communicated with each other via the communication unit 52. In this way, the ink supply unit 12, the first supply tube SR1 (ink supply unit 12 side), the first chamber R1, the communication unit 52, the second chamber R2, the first supply tube SR1 (jet head 11 side), and the ejection head. The ink supply unit 12 communicates with the ejection head 11 in the order of 11.

  An opening is formed in a portion (left end in the drawing) different from the partition portion 51 in the wall portion surrounding the first chamber R1 of the storage chamber forming member 50. The opening is formed to communicate the first chamber R1 and the outside of the ink storage chamber RM. A flexible member F is attached to the opening, and the opening is closed by the flexible member F.

  The valve VB is provided across the first chamber R1 and the second chamber R2. The valve VB has a plate-like portion V1, a flange portion V2, and a shaft portion V3. The plate-like portion V1 is bonded to the flexible member F. The flange portion V2 is provided in the second chamber R2. The flange portion V2 is provided in the second chamber R2. A seal portion V4 that closes the communication portion 52 is formed in the flange portion V2. The communication portion 52 is blocked by the seal portion V4 coming into contact with the partition portion 51.

  The shaft portion V3 is disposed so as to penetrate the communication portion 52. The plate-like portion V1 and the flange portion V2 are connected by a shaft portion V3. In the valve VB, when the flexible member F bends in the direction in which the internal volume of the ink storage chamber RM decreases, the seal portion V4 is separated from the partition portion 51 and the communication portion 52 is opened.

  The urging mechanism SP is disposed between the plate-like portion V1 and the partition portion 51. A spring member or the like is preferably used as the urging mechanism SP. The urging mechanism SP urges the plate-like portion V1 leftward in the drawing (in a direction away from the partition portion 51) so as to bend the flexible member F in a direction in which the internal volume in the first chamber R1 increases. The urging force of the urging mechanism SP is such that the seal portion V4 opens the communication portion 52 when the ink storage chamber RM becomes smaller than a predetermined pressure, and the seal portion V4 blocks the communication portion 52 at other times. Is set.

  When ink is ejected from the ejection head 11, the seal portion V <b> 4 blocks the communication portion 52, so the flow path from the first chamber R <b> 1 to the ejection head 11 becomes negative pressure. When the force to bend the flexible member F by this negative pressure becomes larger than the biasing force of the biasing mechanism SP, the flexible member F is bent and the communicating portion 52 is opened.

  Since the first chamber R1 and the ejection head 11 are in communication with each other, and the second chamber R2 and the ink supply unit 12 are in communication with each other, ink passes from the second chamber R2 through the communication unit 52 to the first chamber R1 side. To be supplied. When the negative pressure from the first chamber R1 to the ejection head 11 is reduced by supplying ink, the urging force of the urging mechanism SP becomes larger than the negative pressure, and the seal portion V4 blocks the communication portion 52. It becomes a state.

  In this way, the valve unit VU has a function of adjusting the ink meniscus of the nozzle by making the ejection head 11 negative pressure from the first chamber R1, and a check valve in which ink flows only from the second chamber R2 toward the first chamber R1. (One-way valve).

  Returning to FIG. 1, the supply pump RP adjusts the direction and flow rate (supply speed) of the ink flowing in the second supply tube SR2. As the direction of ink flow, ink can be switched and supplied in each of the forward direction from the ejection head 11 to the ink supply unit 12 and the reverse direction from the ink supply unit 12 to the ejection head 11. ing. When the ink flow is forward in the second supply tube SR2, the ink flow is in the direction from the ink supply unit 12 to the ejection head 11 in the first supply tube SR1. Further, when the flow rate is adjusted, the supply pump RP can change the flow rate of the ink supplied at least in the forward direction depending on whether or not a cap member 42 described later covers the ejection surface 11A. It can be done. In this case, variable control of the flow velocity is performed by the control device CONT.

  The maintenance mechanism MN performs maintenance of the ejection head 11. The maintenance mechanism MN has a cap member 42 and a drive mechanism ACT. The cap member 42 is formed in a plate shape using a material such as rubber or elastomer, for example. The cap member 42 has a contact surface 42 a that is in close contact with the ejection surface Ha of the head H. The contact surface 42 a is provided to face the ejection surface Ha of the head H. The cap member 42 is formed to have a dimension that covers at least a range where the nozzle NZ is formed on the ejection surface Ha. For this reason, the cap member 42 has a configuration in which the surface of the ejection surface Ha on which the nozzle NZ is formed is covered and covered.

  In the present embodiment, an absorbing member (not shown) for receiving ink ejected from each nozzle 13 of the ejection head 11 is provided separately from the cap member 42. The absorbing member can be disposed on the flight path when the cap member 42 is retracted from the flight path of the ink ejected from each nozzle 13. In this case, the absorbing member disposed on the ink flight path receives ink from the head.

  The drive mechanism ACT moves the cap member 42 to and from the head H. As the drive mechanism ACT, an actuator such as a cam mechanism, a motor mechanism, or an air cylinder mechanism is used. Of course, other actuators may be used.

FIG. 6 is a block diagram illustrating an electrical configuration of the printer apparatus PRT.
The printer device PRT in the present embodiment includes a control device CONT that controls the overall operation. Connected to the control device CONT are an input device 59 for inputting various information relating to the operation of the printer device PRT and a storage device 60 storing various information relating to the operation of the printer device PRT.

  Each part of the printer device PRT, such as an ink ejection mechanism IJ, a transport mechanism CR, and a maintenance mechanism MN, is connected to the control device CONT. The printer device PRT includes a drive signal generator 62 that generates a drive signal to be input to a drive unit including the piezoelectric element 25. The drive signal generator 62 is connected to the control device CONT.

  The drive signal generator 62 receives data indicating the amount of change in the voltage value of the ejection pulse input to the piezoelectric element 25 of the ejection head 11 and a timing signal that defines the timing for changing the voltage of the ejection pulse. The drive signal generator 62 generates a drive signal such as an ejection pulse based on the input data and timing signal.

Next, the operation of the printer apparatus PRT configured as described above will be described.
When the printing operation by the ejection head 11 is performed, the control device CONT places the recording medium M on a support surface (not shown) by the transport mechanism CR. After arranging the recording medium M, the control device CONT inputs a drive signal from the drive signal generator 62 to the piezoelectric element 25 based on the image data of the image to be printed.

  When a drive signal is input to the piezoelectric element 25, the piezoelectric element 25 expands and contracts and ink is ejected from the nozzle 13. A desired image is formed on the recording medium M by the ink ejected from the nozzles 13.

  As a maintenance operation of the ejection head 11, a capping operation is performed. When performing the capping operation, the control device CONT presses the cap member 42 toward the ejection head 11 by the drive mechanism ACT. By this operation, a gap is formed between the cap member 42 and the ejection head 11.

  When the printer device PRT is turned off and kept in an unused state, the solid content in the ink stored in the ink supply unit 12 separates and settles (precipitates), and the solid content concentration of the ink becomes uneven. May be. Then, when solid matter sedimentation and solid content concentration non-uniformity occur in this way, when the power is turned off, the power is turned on again to eject ink, and when the printing is performed, the sedimented solid matter remains as it is in the ejection head. 11 is supplied to the nozzle 11 side, resulting in inconveniences such as nozzle clogging of the ejection head 11 and unevenness in recording quality.

  Therefore, in order to prevent such inconvenience, the ink is circulated between the ink supply unit 12 and the ejection head 11. The control device CONT operates the supply pump RP, and the ink is forward (in the direction of the ejection head 11 → the direction of the ink supply unit 12) or in the reverse direction (the direction of the ink supply unit 12 → the ejection head 11) in the second supply tube SR2. Make it flow.

  As a specific example, the control device CONT drives the supply pump RP so that ink flows in the forward direction in a state where the ejection surface 11A of the ejection head 11 is covered with the cap member 42 as shown in FIG. By this operation, the first chamber R1 becomes negative pressure, the seal portion V4 of the valve VB opens the communicating portion 52, and the valve unit VU is opened, so that the ink supply portion 12 and the ejection head 11 are communicated. It becomes a state. Therefore, ink is supplied from the ink supply unit 12 to the ejection head 11 via the first supply tube SR1. At this time, the inside of the ejection head 11 located on the upstream side of the supply pump RP has a negative pressure. However, since the ejection surface 11A is covered by the cap member 42, air does not flow from the nozzle 13 and ink is ejected from the nozzle 13. There is no leakage. For this reason, it is possible to increase the flow rate (supply speed) of the ink so that the settled solid component can be easily stirred. Since this operation is performed in a state where the power of the printer device PRT is turned on, it takes a short time to supply ink.

As another aspect, the control device CONT operates the supply pump RP so that the ink flows in the forward direction with the ejection surface 11A of the ejection head 11 not covered with the cap member 42 as shown in FIG. It doesn't matter if you do. In this case, the control device CONT drives the supply pump RP so that the ink pressure P _I becomes a pressure that maintains the ink meniscus in the nozzle 13 in order to prevent ink from flowing in from the nozzle 13.

When the pressure P _O in the first supply tube SR1 necessary for the ink from the ink supply unit 12 to pass through the valve unit VU is −100 Pa, and the pressure P _M for maintaining the meniscus in the nozzle 13 is −200 Pa, in the liquid driving step, the pressure P _I of the ink during this time value (e.g., -150Pa etc.) so that, to adjust the feed rate of ink by the supply pump RP. When the pressure P _{I at} which ink flows is larger than the pressure P _O , the ink does not flow because the valve unit VU remains closed. In addition, when the pressure P _{I at} which the ink flows is smaller than the pressure P _M for maintaining the meniscus at the nozzle 13, the ink meniscus cannot be held at the nozzle 13, and the ink discharge amount cannot be accurately controlled. Therefore, it is preferable here that P _M <P _I <P _O. Each of the above numerical values is merely an example, and the present invention is not limited to this.

  The ink supply operation of the aspect shown in FIG. 8 is performed during a period in which the power of the printer device PRT is turned on and is different from the period in which ink is ejected onto the recording medium M by the ejection head 11. Can do. In addition, after the ink supply operation of the mode shown in FIG. 7 is performed and the ink settling is eliminated, the ink supply operation of the mode shown in FIG. 8 is preferably performed at a flow rate at which the ink does not settle.

  As another aspect, the control device CONT drives the supply pump RP so that the ink flows in the reverse direction with the ejection surface 11A of the ejection head 11 not covered with the cap member 42, as shown in FIG. You can also. In this case, since the first chamber R1 is in a pressurized state and the flexible member F bends in a direction that increases the volume of the first chamber R1, the seal portion V4 remains in the state where the communication portion 52 is blocked. Become. For this reason, the valve unit VU remains closed, and no ink flows in the first supply tube SR1.

  Further, the ink that has flowed to the ejection head 11 via the second supply tube SR2 is discharged from the nozzle 13 to the outside of the ejection head 11. Here, since the cap member 42 is retracted from the ejection path of the ejection head 11, the discharged ink is received by an absorbing member (not shown). Thus, the flushing (cleaning) operation can be performed by the ink supplied from the second supply tube SR2 side.

  When printing is performed using the ejection head 11, foreign matter may adhere to the nozzle 13 or thickened ink may adhere to the nozzle 13. In such a case, at least one of the nozzles 13 provided in the ejection head 11 may be clogged, resulting in a poor ejection state. The ink supply operation as shown in FIG. 9 can be performed for the purpose of eliminating such a defective ejection state of the nozzle 13. By the ink supply operation, the nozzle 13 having a poor ejection state can be cleaned, so that the suction mechanism for the cap member 42 becomes unnecessary. Of course, the ink supply operation may be performed for other purposes or in other cases.

  As described above, according to the present embodiment, the first supply tube SR1 that supplies ink from the ink supply unit 12 to the ejection head 11 and the first supply tube SR1 are provided separately from the ejection head 11 and the ink supply. The second supply tube SR2 that communicates with the section 12 is supplied, and ink is supplied in the forward direction by the supply pump RP provided in the second supply tube SR2 in a state where the cap member 42 is in close contact with the ejection head 11. As a result, ink is supplied with the nozzle 13 sealed. For this reason, air can be prevented from flowing in from the nozzles while supplying ink. In addition, it is possible to prevent ink from leaking from the nozzles.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, an example of a printer using a line-type head has been described. However, the present invention is not limited to this, and a scanning-type head is used as shown in FIG. The present invention can also be applied to the printer device PRT2.

  The configuration of the printer device PRT2 will be briefly described. The printer device PRT2 includes a printer main body 105 and a carriage 104 on which the sub tank 102 and the ejection head 103 are mounted. The printer main body 105 includes a carriage moving mechanism 154 that reciprocates the carriage 104, a capping device 150 that is used for a cleaning operation that sucks thickened ink from each nozzle of the ejection head 103, and an ink supply tube 134. An ink cartridge 106 that stores ink to be supplied to the ejection head 103 is provided. The printer main body 105 is provided with a paper feed mechanism (not shown) that transports recording paper. The paper feed mechanism is a paper feed motor or a paper feed roller (not shown) that is rotationally driven by the paper feed motor. The recording paper is sequentially fed onto the platen 113 in conjunction with a recording (printing / printing) operation.

  The carriage moving mechanism 154 includes a guide shaft 108 installed in the width direction of the printer main body 105, a motor 109, a drive pulley 110 connected to a rotation shaft of the motor 109 and driven to rotate by the motor 109, and a drive pulley 110. And a idler pulley 111 provided on the opposite side of the printer body 105 in the width direction, and a timing belt 112 that is stretched between the drive pulley 110 and the idler pulley 111 and connected to the carriage 104. By driving the motor 109, the carriage 104 reciprocates along the guide shaft 108 in the main scanning direction.

  The capping device 150 is disposed at a home position in the printer main body 105. This home position is an end area outside the recording area within the movement range of the carriage 104, and is set to a position where the carriage 104 is located when the power is turned off or when recording is not performed for a long time. Has been. The printer device PRT2 is configured as described above.

  In the above embodiment, the configuration in which the ejection head 11 is directly connected to the ink supply unit 12 has been described as an example. However, the present invention is not limited to this. As shown in FIGS. 10A and 10B, an ink cartridge (main tank) 106 and a sub tank 102 are prepared as tanks for storing ink, and the sub tank 102 and the ejection head 103 are respectively provided. A configuration in which ink is circulated may be used. In this case, a first supply tube SR1 and a second supply tube SR2 are provided as flow paths for circulating ink, a valve unit VU is disposed in the first supply tube SR1, and a supply pump RP is disposed in the second supply tube SR2. Thus, the present invention can be applied.

  In the above description, an ink jet printer and an ink cartridge are employed. However, a liquid ejecting apparatus that ejects or discharges liquid other than ink and a liquid container that contains the liquid are employed. Also good. The present invention can be used for various liquid ejecting apparatuses including a liquid ejecting head that ejects a minute amount of liquid droplets. In addition, a droplet means the state of the liquid discharged from the said liquid ejecting apparatus, and shall also include what pulls a tail in granular shape, tear shape, and thread shape. The liquid here may be a material that can be ejected by the liquid ejecting apparatus.

  For example, it may be in the state when the substance is in a liquid phase, and may be in a liquid state with high or low viscosity, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts) ) And a liquid as one state of the substance, as well as particles in which functional material particles made of solid materials such as pigments and metal particles are dissolved, dispersed or mixed in a solvent. In addition, typical examples of the liquid include ink and liquid crystal as described in the above embodiments. Here, the ink includes general water-based inks and oil-based inks, and various liquid compositions such as gel inks and hot-melt inks.

  As a specific example of the liquid ejecting apparatus, for example, a liquid containing a material such as an electrode material or a coloring material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, a color filter, or the like in a dispersed or dissolved state. It may be a liquid ejecting apparatus for ejecting, a liquid ejecting apparatus for ejecting a bio-organic material used for biochip manufacturing, a liquid ejecting apparatus for ejecting a liquid as a sample used as a precision pipette, a textile printing apparatus, a microdispenser, or the like.

  In addition, transparent resin liquids such as UV curable resin to form liquid injection devices that pinpoint lubricant oil onto precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. A liquid ejecting apparatus that ejects a liquid onto the substrate or a liquid ejecting apparatus that ejects an etching solution such as an acid or an alkali to etch the substrate may be employed. The present invention can be applied to any one of these ejecting apparatuses and liquid containers.

  PRT, PRT2 ... Printer device (liquid ejecting device) IJ ... Ink ejecting mechanism CONT ... Control device VU ... Valve unit (check valve) RP ... Supply pump (liquid driving unit) RM ... Ink storage chamber VB ... Valve SP ... Energizing Mechanism F ... Flexible member SR1 ... First supply tube (first supply path) SR2 ... Second supply tube (second supply path) 11 ... Ejection head (liquid ejection head) 12 ... Ink supply part (liquid storage part) 13 ... Nozzle.

Claims (9)

A liquid ejecting head that ejects liquid supplied to the common liquid chamber from a plurality of nozzles;
A first path for supplying the liquid to the common liquid chamber of the liquid jet head;
A second path that is provided separately from the first path and forms a circulation path with the first path;
A valve provided in the first path and capable of regulating the flow of the liquid in the first path ;
There is a liquid chamber provided with a flexible wall that can be bent and deformed on the side of the common liquid chamber from the communication portion that is blocked when the flow of the liquid is restricted, and the pressure in the liquid chamber becomes smaller than a predetermined pressure, and the liquid When the flexible wall bends in a direction in which the volume of the chamber decreases, the flow of the liquid is allowed, and the flexible wall moves in a direction in which the pressure becomes equal to or greater than the predetermined pressure and the volume of the liquid chamber increases. A valve that regulates the flow of the liquid when bent;
A liquid drive unit provided in the second path and capable of flowing the liquid in the circulation path;
With
The liquid drive unit is driven so that the liquid in the circulation path flows in a direction to increase the volume of the liquid chamber, and the liquid is discharged from the nozzle by regulating the flow of the liquid by the valve. An operation of the liquid ejecting apparatus.   The liquid drive unit is driven when the liquid ejecting head is not ejecting the liquid onto the ejecting medium in a circulation operation in which the valve allows the flow of the liquid and circulates the liquid in the circulation path. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting apparatus is performed as described above. A cap portion covering the ejection surface on which the nozzles of the liquid ejection head are formed;
The liquid ejecting apparatus according to claim 2, wherein the circulation operation is performed in a state where the ejection surface is covered with the cap portion. 4. The liquid ejecting apparatus according to claim 2, wherein, in the circulation operation, the liquid driving unit is driven so as to have a pressure that maintains a meniscus of the liquid in the nozzle. 5. A liquid reservoir that communicates with the first path and the second path and forms part of the circulation path;
When the liquid ejecting head ejects the liquid onto an ejecting medium, the liquid in the reservoir is supplied to the common liquid chamber via the first path;
5. The discharge operation is performed by causing the liquid in the circulation path to flow in the second path in a direction from the liquid reservoir to the liquid ejecting head. The liquid ejecting apparatus according to any one of the above. A support surface for supporting the medium from which the liquid is ejected, and a transport path through which the medium is transported;
The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting head is provided so as to be movable in a gravitational direction above the support surface. A cap portion covering the ejection surface on which the nozzles of the liquid ejection head are formed;
The liquid ejecting apparatus according to claim 6, wherein the cap portion retreats below the support surface when the liquid is ejected onto the medium. A liquid reservoir that communicates with the first path and the second path and forms part of the circulation path;
A plurality of the common liquid chamber, the first path, the second path, and the liquid storage section so that different liquids can be ejected from a plurality of precursor nozzles;
The liquid ejecting apparatus according to claim 1, wherein the plurality of liquid storage units are arranged so as to be aligned in a direction in which a medium from which the liquid is ejected is conveyed. A liquid reservoir that communicates with the first path and the second path and forms part of the circulation path;
The liquid ejecting apparatus according to claim 1, further comprising: a liquid supply path that supplies the liquid stored in the liquid cartridge to the liquid storage unit.

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