JP4962041B2 - Cleaning apparatus, fluid ejecting apparatus and cleaning method in fluid ejecting apparatus - Google Patents

Description

  The present invention relates to a cleaning device, a fluid ejecting device, and a cleaning method in a fluid ejecting device that performs cleaning by sucking a fluid from a nozzle of a fluid ejecting unit.

  2. Description of the Related Art Conventionally, an ink jet recording apparatus that is one of fluid ejecting apparatuses has been provided with a cleaning device (maintenance device) that prevents or eliminates clogging of nozzles of a recording head that ejects ink as a fluid. The cleaning device includes a cap that can be capped on the recording head so as to cover the nozzle, and a suction pump 55 that can depressurize the cap in the capped state. During cleaning, with the recording head capped by the cap, the suction pump 55 is driven to depressurize the inside of the cap, and foreign matter such as thickened ink, bubbles, and paper dust is sucked and discharged from the nozzle together with the ink. It was.

  By the way, bubbles are easily mixed in the ink when the ink cartridge is replaced, and are easily retained in the ink flow path from the ink cartridge to the nozzle of the recording head. In particular, the ink flow path tends to stay in a chamber where the ink flow path is wider than the cross-sectional area of other flow paths at the place where the filter and valve are disposed. This is because in this type of chamber, the ink flow rate slows down and the force that pushes out bubbles is weak, and the buoyancy causes bubbles to be relatively difficult to discharge, such as the upper wall and upper corners (corners) of the chamber. This is because they gather and stay. Further, the staying bubbles gradually grow at the staying portion and flow to the recording head when it grows to some extent, and there is a possibility that the printing quality is deteriorated, for example, causing missing dots where ink is not ejected from the nozzles. Even if this type of bubble or foreign matter is sucked from the nozzle by the cleaning device, the flow rate thereof is not sufficiently high, so it has been difficult to be discharged.

Therefore, a differential pressure valve (choke valve) is provided in the middle of the ink flow path from the ink cartridge to the recording head, and when the ink is sucked from the nozzle by the cleaning device, the differential pressure valve is closed and the ink is sufficiently reduced. There is known an ink jet recording apparatus that performs so-called choke cleaning in which pressurized ink is supplied from a cartridge side and a differential pressure valve is opened to discharge ink at a high flow rate at a stroke (for example, Patent Document 1). When performing choke cleaning, the ink pressure from the ink cartridge is first stopped, the ink is sucked from the nozzle by the cleaning device to close the differential pressure valve, and the ink flow path downstream from the closed position In the stage where the negative pressure was sufficiently accumulated and reduced, the driving of the pressure pump was resumed and the pressure ink was supplied to open the differential pressure valve and discharge the ink at a high flow rate.
JP 2006-82349 A

  However, when the ink in the flow path is depressurized at the time of chalk cleaning, minute bubbles are deposited in the ink by this depressurization. The minute bubbles deposited during the chalk cleaning do not disappear (re-dissolve) for a while after the decompression is cancelled. Therefore, if printing is started immediately, the minute bubbles cause a printing defect. This kind of printing failure can be reduced to some extent by providing a sufficient waiting time after the decompression is released so that minute bubbles disappear (re-dissolve), or by sucking again to discharge minute bubbles. However, in the former case, there is a problem that cleaning takes time (for example, 5 minutes or more), and in the latter case, there is a problem that the amount of ink consumption increases. For this reason, although the bubble discharge performance is finally lowered, it has to be dealt with at a reduced pressure value that does not cause the bubbles to be deposited. For this reason, it has been a challenge to construct a cleaning sequence that balances the bubble discharge and the printing stability while suppressing the cleaning time and ink consumption.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide gas such as bubbles generated in the fluid in the fluid supply flow path due to pressure reduction during cleaning for sucking fluid from the nozzle of the fluid ejecting head. Another object of the present invention is to provide a cleaning device, a fluid ejecting device, and a cleaning method in a fluid ejecting apparatus that can quickly eliminate foreign particles.

The present invention relates to a cleaning to torque cleaning device fluid ejecting head that ejects fluid from Bruno nozzle occlusion provided in the middle of the flow-supplying channel for supplying fluid from the fluid supply to the fluid ejecting head a valve, a first pressure means for pressurizing fluid from upstream of the closing valve, a suction means for sucking the fluid from the front Symbol nozzle, by suction on the suction unit while being closed the closure valve after depressurizing the downstream fluid from said blocking valve, by flowing said occlusion valve is opened so pressurized to the first pressurizing means fluid to perform the cleaning for sucking and discharging the fluid from the front Symbol nozzle and control means, after the end of the cleaning, and summarized in that and a second pressure means for increasing the fluid pressure of the fluid of the fluid supply channel under pressure through said nozzle.

According to this, by suction from the nozzle by the suction means in a state in which the closure valve is closed, the flow of the fluid supply passage is decompressed in the decompression state, the closure valve is opened, the first fluid pressurized by the pressurized source is the fluid from the nozzles by flow to the lower stream side is sucked and discharged through a closed valve which is opened by cleaning (choke cleaning) is performed. Gaseous foreign matter (for example, microbubbles) is generated in the portion of the fluid decompressed by the decompression in the fluid supply flow path at the time of cleaning. However, after the cleaning, the flow of the fluid-supplying passage is pressurized through the nozzle by the second pressurizing unit. As a result, most or all of the gaseous foreign matters generated in the fluid disappear quickly. For this reason, even if the ejection of the fluid by the fluid ejecting head is started immediately after cleaning, it is possible to effectively avoid the inclusion of gaseous foreign substances in the ejected fluid.

In the cleaning apparatus of the present invention, the second pressure means causes pre SL fluid at least a portion of the region of the downstream portion communicating with the nozzle of the fluid supply passage pressurizes increasing the fluid pressure It is preferable. The downstream part communicating with the nozzle is, for example, when there is a location where pressure transmission is interrupted (for example, valve closing) in the middle of the fluid supply flow path, It refers to the channel portion that communicates, and pressurizes at least the channel portion to increase the fluid pressure. Of course, in the case where there is no such pressure transmission blocking portion, the case where the fluid in the entire region in the fluid supply channel is pressurized is also included.

According to this, the second pressurizing unit, the pressurized fluid at least a portion of the region of the downstream portion communicating with the nozzle of the fluid supply flow path to increase its fluid pressure through a nozzle, through the nozzle pressure while suppressing the leakage of the nozzle or these fluids by the, the gaseous inclusions in the fluid in the area in which the fluid pressure is increased can be quickly eliminated by pressurization.

In the cleaning apparatus of the present invention, a pressure reducing valve is provided in the middle of the fluid supply flow path to open the valve chamber by depressurizing the valve chamber communicating with the nozzle from the nozzle of the fluid ejecting head, It is preferable that the second pressurizing unit pressurizes the fluid in the fluid supply channel from both the upstream side and the downstream side with the pressure reducing valve interposed therebetween.

According to this, the pressure reducing valve provided in the middle of the fluid supply channel is configured not to open by pressurization regardless of the upstream side or the downstream side, but the pressure reducing valve is interposed by the second pressurizing means. Since the fluid in the fluid supply flow path is pressurized from both the upstream and downstream directions sandwiched between the two, the entire area pressurized in the cleaning (the downstream area of the closing valve) is pressurized to The gaseous foreign matter generated in the fluid can be effectively eliminated.

In the cleaning apparatus of the present invention, wherein the first pressure means and the second pressure means, and this for performing pressurization with the same drive unit are preferred.

According to this, a 2nd pressurization means pressurizes using the drive part same as a 1st pressurization means. Therefore, the number of configurations to be added / changed when providing the second pressurizing unit is small.

The present invention is a fluid ejecting apparatus, comprising: a fluid supply source; a fluid ejecting head that ejects fluid supplied from the fluid supply source through a fluid supply flow path from a nozzle; and the cleaning device according to the invention. Is the gist. According to this, since the fluid ejecting apparatus includes the cleaning device of the present invention, the same effect as the above invention can be obtained.

The present invention relates to a fluid ejecting head cleaning to torque cleaning method for ejecting fluid from Bruno nozzle, closing the fluid supply source provided in the fluid ejection head fluid supply passage on supplying fluid to塞弁in a state of being closed and a vacuum step of depressurizing the downstream fluid from the closing valve by which aspirating fluid from the nozzle, said closure valve downstream fluid state like that reduce the pressure from the closure valve opens is a valve, by flowing the pressurized fluid from upstream the closing valve, a discharge step of performing cleaning for sucking and discharging the fluid from the front Symbol nozzles, after the discharge step, the flow of the fluid supply channel And a pressurizing step of increasing the fluid pressure by applying pressure through the nozzle . According to this, the same effect as the invention of the cleaning device can be obtained.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
FIG. 1 is a plan view of the ink jet recording apparatus with the outer case removed.
An ink jet recording apparatus (hereinafter simply referred to as a printer 11) as a fluid ejecting apparatus has an inside of a main body case 12 formed of a box having a substantially rectangular parallelepiped shape whose upper side (the front side in FIG. 1) opens. A platen 13 is installed in the main body case 12 so as to extend along the main scanning direction (left-right direction in FIG. 1). A recording medium (not shown) as a target is conveyed in the sub-scanning direction (vertical direction in FIG. 1) via a paper feeding means (not shown) while being supported by the platen 13.

  Further, a rod-shaped guide shaft 14 is installed in the main body case 12 so as to extend in parallel with the platen 13 in a state where the axial direction thereof coincides with the main scanning direction. The carriage 15 has a guide shaft 14 inserted through its rear portion (upper portion in FIG. 1) and is supported so as to be capable of reciprocating along the axial direction of the guide shaft 14. A timing belt 17 is wound around a pair of pulleys 16a and 16b that are respectively pivotally supported at two positions separated by a predetermined distance in the main scanning direction at the rear portion of the main body case 12, and the carriage 15 is on the rear side (FIG. 1). The upper side is fixed to the timing belt 17. In FIG. 1, the right pulley 16 a is connected to a drive shaft of a carriage motor 18 disposed near the rear right end of the main body case 12, and the timing belt 17 is driven when the carriage motor 18 is driven forward and backward. The carriage 15 reciprocates along the guide shaft 14.

  A recording head 20 serving as a fluid ejecting unit that ejects ink serving as a fluid is provided below the carriage 15. A plurality of valve units 21 are mounted on the carriage 15. In the present embodiment, a total of four valve units 21 are provided for each ink color, and the pressure of each of the black, yellow, magenta, and cyan inks is adjusted by each valve unit 21 to the recording head 20. Supplied.

  The cartridge holder 22 provided at one end (the right end in FIG. 1) of the main body case 12 is detachably loaded with four ink supply sources (fluid storage means) corresponding to the ink color. ing. Each cartridge holder 22 is connected to each valve unit 21 through an ink supply channel 24.

  As shown in FIG. 1, a pressurizing pump device 25 is provided above the loading position of the ink cartridge 23 while being supported by the main body case 12. The pressurizing pump device 25 can suck the atmosphere and discharge it as pressurized air, and the discharged pressurized air is supplied to the atmosphere release valve 28 through the pressurizing tube 27.

  The air release valve 28 is connected to the cartridge holder 22 through four air supply tubes 29, and pressurized air is introduced into the ink cartridge 23. The air release valve 28 is a valve that can be switched between an open state in which an internal chamber is opened to the atmosphere and a closed state in which communication with the atmosphere in the chamber is blocked, and the pressure pump device 25 is driven. Sometimes it is closed.

  Further, a maintenance device 31 is provided at a position corresponding to a position immediately below when the carriage 15 is positioned at a home position (a position on the right side in FIG. 1) that is a standby position during non-printing. The maintenance device 31 includes a cap 32 and a wiper 33. Each of the cap 32 and the wiper 33 is configured to be movable up and down. The cap 32 is raised during non-printing to cap the recording head 20 in order to prevent the ink in the nozzles of the recording head 20 from drying. Also, when performing cleaning (including chalk cleaning) performed by sucking ink from the nozzles of the recording head 20, the cap 32 rises to cap the recording head 20. Further, the wiper 33 wipes the nozzle opening surface of the recording head 20 by moving the carriage 15 in the raised state. The wiper 33 is wiped up at a predetermined time after the cleaning of the recording head 20 is completed, and wipes off ink adhering to the nozzle opening surface and adjusts the ink meniscus in the nozzle. In addition, a pressurizing tube 34 branched from the pressurizing tube 27 is connected to the cap 32, so that pressurized air can be introduced into the cap 32. An electromagnetic opening / closing valve 35 is provided in the middle of the pressurizing tube 34.

  FIG. 3 shows a basic configuration of an ink supply system and a cleaning system (cleaning apparatus) in the recording apparatus. Here, the ink supply system shown in FIG. 3 is an air pressure supply type. FIG. 3 shows only the ink supply system for one color.

  The pressure pump device 25 includes a pressure pump motor 41 and a pressure pump 42. The pressurizing pump 42 is driven when the pressurizing pump motor 41 is driven forward. The air release valve 28 provided in the middle of the pressure tube 27 that connects the discharge port of the pressure pump 42 and the ink cartridge 23 is always closed by the biasing of a spring (not shown), and the pressure pump motor 41. Is driven reversely, a pressing portion (not shown) is opened by pressing the lever of the air release valve 28 against the bias of the spring.

  The ink cartridge 23 has a case 23a formed in an airtight state, and an ink pack 23b made of a flexible film formed in a bag shape is accommodated in the case 23a. In a state where the ink cartridge 23 is loaded, the pressurized tube 27 is connected so as to communicate with the air chamber 43 between the case 23a and the ink pack 23b, and the pressurized air sent from the pressure pump device 25 is It is introduced into the air chamber 43. The ink packs 23b in the four ink cartridges 23 are filled with inks of different colors.

  As shown in FIG. 3, in the state where the ink cartridge 23 is loaded in the cartridge holder 22, the ink outlet 23 c of the ink pack 23 b is connected to the ink supply channel 24. The air pumped from the pressurizing pump is introduced into the air chamber 43 in the case 23a and the ink pack 23b is crushed so that the ink pressurized to a predetermined pressure is supplied from the ink pack 23b to the valve unit 21. . The valve unit 21 incorporates a choke valve 45 (differential pressure valve) and a pressure reducing valve 46 as a closing valve, and the ink supplied into the valve unit 21 is sent to the pressure reducing valve 46 through the choke valve 45, and the pressure reducing valve 46 The pressure is reduced to a predetermined ink pressure (negative pressure) slightly lower than the atmospheric pressure by 46, and the reduced ink is supplied to the recording head 20. The choke valve 45 is constituted by a differential pressure valve that is opened and closed by a differential pressure between the upstream ink pressure and the downstream ink pressure. The choke valve 45 and the pressure reducing valve 46 are provided for each ink flow path of each ink color.

  A filter device 48 having a filter 49 for removing foreign matter in the ink is provided in the middle of the ink supply flow path 47 connecting the valve unit 21 and the recording head 20. Deposited in the ink due to air bubbles (oxygen or nitrogen) that have permeated gas through the ink supply flow path 24 or the resin parts (tubes, etc.) that make up the ink supply flow path 24 when the ink cartridge is replaced. The grown bubbles are captured by the filter 49.

  The recording head 20 includes a nozzle 20b that opens to the nozzle opening surface 20a, and an ink chamber 20c that communicates with the nozzle 20b. The ink chamber 20 c communicates with an ink supply channel 47 that is partially formed in the recording head 20. Further, the recording head 20 incorporates a discharge driving element 51 at a position corresponding to the ink chamber 20c, and the discharge force (discharge pressure) when the discharge driving element 51 is driven is applied to the ink in the ink chamber 20c. Ink is ejected from the nozzle 20b. The ejection driving element 51 may be a piezoelectric vibration element or an electrostatic driving element that ejects ink droplets with ejection pressure caused by vibration, or the growth / contraction of bubbles generated by boiling the film locally by applying heat to the ink. An electrothermal conversion element that ejects ink droplets by use can be employed.

  As shown in FIG. 3, the maintenance device 31 includes a cap 32, a lifting mechanism 52 that lifts and lowers the cap 32, a suction pump 55 provided in the middle of a discharge tube 54 that extends from the bottom of the cap 32, and a suction pump And a suction pump motor 56 for driving 55. The cap 32 is connected to the lifting mechanism 52 and is lifted and lowered via the lifting mechanism 52 by the power of the electric motor 53. In the state where the cap 32 is disposed at the capping position (upward position) shown in FIG. 3, the cap 32 abuts on the nozzle opening surface 20 a of the recording head 20 while surrounding the nozzle 20 b. Further, the discharge tube 54 is connected in communication with the inside of the cap 32, and one end thereof is inserted into the waste liquid tank 57. As the lifting mechanism, a machine in which the cap 32 supported on the slider moves up to the capping position by pushing the lever on the lifting mechanism side and moving the slider diagonally upward while the carriage 15 moves to the home position. A mechanically driven lifting mechanism may be employed.

  The suction pump 55 is driven by the power of the suction pump motor 56. Under the capping state in which the cap 32 is in contact with the nozzle opening surface 20 a of the recording head 20, the suction pump 55 is driven to suck the thickened ink in the nozzle 20 b and discharge it into the waste liquid tank 57. It has come to be. The suction pump motor 56 uses a suction pump motor, and uses a paper feed motor (not shown) that drives a conveyance roller that constitutes a conveyance mechanism for conveying a recording medium. A configuration in which the suction pump 55 is driven using the power of the feed motor can also be employed. In this case, the suction pump 55 is driven when the paper feed motor is driven reversely in the direction opposite to the paper transport direction, and the suction pump 55 is set to the released state when the paper feed motor is driven forward. Constitute.

  Here, the chalk cleaning is performed by introducing the negative pressure into the cap 32 in contact with the recording head 20 by driving the suction pump 55 in a state where the pressure supply of the ink from the ink cartridge 23 is stopped. Done. When a negative pressure is introduced into the cap 32 and a suction force reaches the nozzle 20b, the ink is sucked from the nozzle 20b and the ink in the ink supply channels 47 and 78 is depressurized, and the choke valve 45 is located upstream and downstream. The valve is closed by the pressure difference from the side. When the pressure pump 42 is driven and pressure supply of ink is started in a state where the downstream region from the choke valve 45 is sufficiently depressurized, the choke valve 45 is opened and the ink flows at a high flow rate at a stroke. And sucked and discharged from the nozzle 20b. Due to this powerful cleaning, bubbles and the like captured by the filter 49 and the like are also discharged. Therefore, in the present embodiment, the suction means includes the cap 32, the discharge tube 54, the suction pump 55, the suction pump motor 56, and the like.

  The pressure reducing valve 46 is a valve that opens when ink is ejected from the nozzle 20b of the recording head 20 and the amount of ink in the internal pressure chamber decreases. Ink with a predetermined ink pressure (negative pressure) is supplied. The pressure reducing valve 46 is opened when the downstream side is depressurized, and is not opened by pressurization from the upstream side. The specific configurations of the choke valve 45 and the pressure reducing valve 46 will be described later.

  The cleaning system according to the present embodiment includes a pressure treatment function that eliminates the fine bubbles generated in the ink by the pressure reduction during the chalk cleaning by holding the ink under pressure in addition to the chalk cleaning function described above. . The pressurizing tube 34 branched from the middle of the pressurizing tube 27 connected to the pressurizing pump device 25 is connected to the cap 32 so as to communicate with the inside thereof. An electromagnetic opening / closing valve 35 is provided in the middle of the pressurizing tube 34. When the electromagnetic on-off valve 35 is opened, the discharge port of the pressurizing pump device 25 and the inside of the cap 32 are in communication with each other, and when the electromagnetic on-off valve 35 is closed, the discharge port of the pressurizing pump device 25 and the inside of the cap 32 are in communication. Is to be blocked. Therefore, when the electromagnetic on-off valve 35 is opened in a state where the pressurizing pump device 25 is driven, pressurized air is supplied into the cap 32. The electromagnetic open / close valve 35 is closed during choke cleaning in the ink sequence and is opened during pressurization. In addition, during the pressurizing process, the region decompressed during the choke cleaning, that is, the entire downstream side of the choke valve 45 is pressurized. Since the pressure reducing valve 46 is not opened by pressurization regardless of the upstream side or the downstream side, when pressure is applied from one end side of the ink supply flow path, the pressure reducing valve 46 is sandwiched between the pressure reducing valve 46 and applied to the opposite flow path region. Pressure does not reach. Therefore, in the pressurizing process, pressurization from the nozzle 20 b side by introducing pressurized air into the cap 32 (pressurization from the downstream side) and pressurization from the upstream side by driving the pressurization pump 42 are performed. Do. Therefore, in this embodiment, the pressurizing means is the pressurizing pump device 25 (pressurizing pump motor 41, pressurizing pump), pressurizing tube 34, electromagnetic on-off valve 35, cap 32, pressurizing tube 27, and air chamber 43. Etc.

  As shown in FIG. 3, a non-volatile memory 59 and a terminal 60 are attached to the ink cartridge 23. The cartridge holder 22 is provided with a terminal 61 at a position corresponding to the terminal 60 on the ink cartridge 23 side, and the terminal 60 and the terminal 61 are in contact with each other when the ink cartridge 23 is loaded in the cartridge holder 22. It has become.

  The printer 11 includes a controller 62 that controls the entire apparatus. The controller 62 is electrically connected to the pressurizing pump motor 41, the electric motor 53, the suction pump motor 56, and the solenoid valve opening / closing valve 58 as an output system. The controller 62 controls the pressurizing pump motor 41, the electric motor 53, the suction pump motor 56, and the solenoid valve opening / closing valve 58 based on a predetermined sequence. The controller 62 can read information from the nonvolatile memory 59 through the connection of the terminals 60 and 61 in a state where the ink cartridge 23 is loaded in the cartridge holder 22. The controller 62 counts the mass (weight) of the ink droplets ejected from the nozzles of the recording head 20 for each color, obtains the ink consumption for each color from the counted value, and determines the ink from the remaining ink amount. The new ink remaining amount obtained by subtracting the consumption amount is written in the nonvolatile memory 59 when the printer 11 is powered off, for example. The printer 11 includes a rotational position sensor 63 that detects the rotational position of the suction pump 55, and the controller 62 grasps the rotational position of the suction pump 55 based on a detection signal input from the rotational position sensor 63. When the controller 62 drives the pressurizing pump motor 41 to pressurize the air chamber 43 to a target air pressure (target value) corresponding to the ink supply pressure, the controller 62 first determines the volume of the air chamber 43 (from the remaining ink amount). The ink supply pressure is adjusted by driving the pressure pump motor 41 by the number of rotations corresponding to the air supply amount determined from the air chamber volume and the target air pressure.

  FIG. 2 is a side view showing the cap and the suction pump. The cap 32 has a square box-shaped cap holder 32a having an open upper surface, and an annular seal portion 32b (sealing wall) made of an elastic material such as an elastomer formed on the upper peripheral portion of the cap holder 32a. Yes. The cap holder 32a and the seal portion 32b are formed by, for example, two-color molding. In the state shown in FIG. 2 in which the cap 32 is at the capping position, the cap 32 abuts against the nozzle opening surface 20a of the recording head 20 in a state of surrounding the nozzle 20b.

  As shown in FIG. 2, a suction pump 55 is provided in the middle of the discharge tube 54 connected to the bottom of the cap 32. The suction pump 55 is constituted by a tube pump in the present embodiment. The suction pump 55 has a cylindrical pump case 65, and a pump wheel 66 is accommodated in the pump case 65 so as to be rotatable about a drive shaft 67. And in this pump case 65, the intermediate part 54a in the middle of the discharge tube 54 is drawn and accommodated along the inner peripheral wall 65a of the pump case 65. As shown in FIG. 2, the discharge tube 54 is routed so as to draw an “Ω” shape along the inner peripheral wall 65 a of the pump case 65.

  An arc-shaped roller guide groove 66 a is formed at a position near the periphery of the pump wheel 66. The roller guide groove 66a extends in an arc shape away from the drive shaft 67 in the radial direction from one end to the other end. A rotation shaft 69a of a roller 69 (pulley) is inserted and supported in the roller guide groove 66a. The rotation shaft 69a is slidable in the roller guide groove 66a.

  When the pump wheel 66 is rotated in the forward rotation direction (the arrow direction in FIG. 2), the roller 69 moves to one end side of the roller guide groove 66a (the outer peripheral side of the pump wheel 66), and the roller 69 is discharged to the discharge tube. A part of 54 is pressed. Therefore, when the pump wheel 66 is rotated in the forward rotation direction, the roller 69 rotates and moves while sequentially crushing (pressing) the intermediate portion 54a of the discharge tube 54 from the cap 32 side to the discharge side. Due to the movement, the inside of the discharge tube 54 closer to the cap 32 than the suction pump 55 is decompressed.

  Here, the suction pump 55 of the present embodiment has a tube handling shape of “Ω”, so that two tubes are arranged side by side inside the portion extending outward from the pump case 65 (on the drive shaft 67 side). Has a constriction (concave part) between the two tubes. This constricted portion becomes a leak point LP where the tube cannot be crushed by the roller 69. The controller 62 can stop the rotation of the suction pump 55 at a position where the roller 69 avoids the leak point LP based on the rotational position information of the suction pump 77 acquired based on the detection signal of the rotational position sensor 63 described above. It has become. When the suction pump 55 stops at a rotational position where the roller 69 avoids the leak point LP, the intermediate portion 54a of the discharge tube 54 is pressed by the roller 69 and is closed.

Next, the structure of the choke valve 45 will be described.
As shown in FIGS. 4A and 4B, the choke valve 45 has a base material 70 made of a synthetic resin, and a concave portion 71 is formed on one side surface of the base material 70. In the bottom surface of the recess 71, an introduction path 72 penetratingly formed in the base material 70 is opened. The introduction path 72 communicates with the ink supply path 24 connected to the ink cartridge 23. In addition, a protrusion 73 is formed on the bottom surface of the recess 71, and a lead-out path 74 is open on the tip surface of the protrusion 73. The lead-out path 74 is formed through the base material 70 and communicates with an ink supply channel 78 (see FIG. 3) extending to the pressure reducing valve 46 side (recording head 20 side).

  A flexible film 75 is fixed to one side surface of the substrate 70 in a state where the concave portion 71 is slackened, and the concave portion 71 is hermetically sealed by the film 75. Thereby, the valve chamber 76 enclosed by the inner surface of the recessed part 71 and the film 75 in the sealed state is formed. When the choke valve 45 is pressurized with ink from the introduction path 72 side, the differential pressure causes the film 75 to open away from the front end surface of the protrusion 73 as shown in FIG. It becomes a valve state. The choke valve 45 is configured such that when the suction pump 55 is driven and the pressure on the lead-out path 74 is reduced in a state where the pressurization of the ink is stopped from the introduction path 72 side, the film 75 is caused by the differential pressure. As shown in FIG. 4B, the valve is brought into contact with the distal end surface of the protrusion 73. Further, even during suction, the valve is opened when pressurized with ink from the introduction path 72 side.

Next, the configuration of the pressure reducing valve 46 will be described in detail.
As shown in FIGS. 5A and 5B, the pressure reducing valve 46 includes a base material 80 made of synthetic resin. A concave portion 81 is formed on one side surface of the substrate 80, and a concave portion 82 is formed on the other side surface. On the side surface of the recess 82, an introduction path 83 formed through the base material 80 is opened. The introduction path 83 communicates with the lead-out path 84 of the choke valve 45 through the ink supply path 78 (see FIG. 3). In addition, a lead-out path 84 penetratingly formed in the base material 80 is opened at the bottom surface of the recess 81. The lead-out path 84 communicates with an ink supply path 47 (see FIG. 3) extending to the recording head 20 side.

  A lid 85 that functions as a spring seat is fitted into the opening of the recess 82 so as to close the opening. A film 86 is fixed to the other side surface of the base material 80 so as to cover the recess 82 from above the lid 85. Thus, an ink supply chamber 87 surrounded by the inner surface of the recess 82 and the film 86 is formed in a sealed state.

  A flexible film 88 is fixed to one side surface of the substrate 80 in a state where the concave portion 81 is slackened, and the concave portion 81 is hermetically sealed by the film 88. Thus, a pressure chamber 89 is formed as a valve chamber surrounded by the inner surface of the recess 81 and the film 88 in a sealed state. A pressure receiving plate 90 narrower than the opening of the recess 81 is fixed to the center of the surface of the film 88 opposite to the recess 81 side.

  A partition wall 91 is provided between the pressure chamber 89 and the ink supply chamber 87 so as to partition both the chambers 87 and 89, and the partition wall 91 communicates with the pressure chamber 89 and the ink supply chamber 87. A hole 92 is formed through. In the ink supply chamber 87, a valve body 94 is a rod-like member extending from the base portion 94 a with a compression spring 93 interposed between the plate-like base portion 94 a and the lid 85. The rod portion 94b is accommodated in a state of being inserted into the communication hole 92. The distal end of the rod portion 94 b of the valve body 94 reaches the close position of the film 88 in the pressure chamber 89.

  On the surface of the base portion 94a of the valve body 94 on the partition wall 91 side, an annular seal member 95 is formed integrally with the base portion 94a so as to surround the rod portion 94b. When the valve body 94 is urged by the compression spring 93 and is brought into pressure contact with the seal member 95 of the partition wall 91, the pressure reducing valve 46 is closed.

  The pressure reducing valve 46 generates a negative pressure in the pressure chamber 89 when the ink in the pressure chamber 89 is supplied from the lead-out path 84 to the recording head 20 and the amount of ink in the pressure chamber 89 decreases. . Due to this negative pressure, the pressure receiving plate 90 is displaced to the concave portion 81 side together with the film 88 and comes into contact with the tip of the rod portion 94b of the valve body 94. Further, the rod is moved by the pressure receiving plate 90 against the urging force of the compression spring 93. When the portion 94 b (valve element 94) is pressed toward the lid body 85 via the film 88, the seal member 95 and the partition wall 91 are separated from each other. Then, the ink in the ink supply chamber 87 flows into the pressure chamber 89 through the communication hole 92, and when the negative pressure in the pressure chamber 89 is slightly reduced by this, the urging force of the compression spring 93 overcomes and the valve body 94. Moves in the valve closing direction, and the communication hole 92 is closed again by the valve body 94 (valve closed state). Thus, the pressure reducing valve 46 is configured to keep the pressure in the pressure chamber 89 constant by repeating the valve closing state and the valve opening state. As long as the pressure reducing valve 46 has a pressure reducing valve function, a valve having another known valve structure such as a check valve or a differential pressure valve may be used.

  Next, the electrical configuration of the printer 11 will be described. FIG. 6 is a block diagram illustrating an electrical configuration of the printer 11. The printer 11 includes a controller 62, and the controller 62 includes a microcomputer 100, a head drive circuit 101, motor drive circuits 102 to 104, and a valve drive circuit 105. The microcomputer 100 is connected to the drive circuits 101 to 105 as an output system, and is connected to a rotational position sensor 63 as an input system.

  The microcomputer 100 has a configuration in which a CPU, an ASIC, a ROM, a RAM, a nonvolatile memory, a clock circuit, various counters, and the like are mounted on a substrate as hardware. The microcomputer 100 includes a control unit 110, a calculation unit 111, a timer 112, a cleaning timer 113, and a cleaning condition setting unit 114 (condition acquisition unit, cleaning unit) as functional parts respectively realized by at least one of hardware and software. A condition setting unit), a pressurizing condition setting unit 115, a remaining ink amount acquiring unit 116, and a time measuring unit 117. In this embodiment, the control part 110 is comprised by ASIC and CPU, and the calculating part 111 is comprised by CPU. The timer 112 and the cleaning timer 113 are constructed by a counter that performs a counting process based on a clock signal from a clock circuit, or a CPU that executes a timer processing program. The cleaning condition setting unit 114 and the pressurization condition setting unit 115 are realized by a CPU that calculates setting conditions with reference to condition setting data (for example, table data) stored in a predetermined storage area of a memory such as a RAM or a nonvolatile memory. Is done. The time measuring means 117 is configured by a CPU that acquires time information from a real time clock built in the printer 11 or a host computer (not shown) connected to the printer 11 via a communication cable.

  The control unit 110 transfers the print data (bitmap data) received by the printer 11 from the host computer to the head drive circuit 101, and causes the head drive circuit 101 to drive the ejection drive element 51 based on the print data, so that the print head Ink droplets are ejected from the 20 nozzles 20b. Further, the control unit 110 transmits driving data for flushing that ejects ink droplets that are not related to printing to the head driving circuit 101.

  Further, the control unit 110 drives and controls the pressure pump motor 41 via the motor drive circuit 102. When the pressure pump motor 41 is driven forward, the pressure pump 42 is driven and air is supplied to the air chamber 43 in the ink cartridge 23 through the pressure tube 27. The control unit 110 calculates the volume of the air chamber 43 based on the ink remaining amount acquired by the ink remaining amount acquiring unit 116, and calculates the pump rotation speed necessary for setting the air chamber 43 to the target pressure from the calculated volume. Then, the pressure pump motor 41 is driven by the number of rotations corresponding to the calculated pump rotation number.

  The control unit 110 receives either an operation command signal for a cleaning switch (not shown) or an elapsed time signal from the cleaning timer 113, or detects an unused ink cartridge 23. In addition, the carriage 15 is disposed at the home position, and the maintenance device 31 performs cleaning. The control unit 110 drives and controls the suction pump motor 56 via the motor drive circuit 103.

  Further, the control unit 110 opens or closes the electromagnetic on-off valve 35 through the valve drive circuit 105 by performing demagnetization control. The electromagnetic open / close valve 35 is closed at least during choke cleaning, and is opened during the pressurizing process performed immediately after choke cleaning in the cleaning sequence.

  The cleaning timer 113 measures the elapsed time from the previous cleaning, and the control unit 110 sets the cleaning condition according to the elapsed time acquired from the cleaning timer 113 when the printer 11 is turned on. 114.

  When receiving a command from the control unit 110, the cleaning condition setting unit 114 refers to the cleaning condition setting table read from a predetermined storage area of the RAM based on the elapsed time counted by the cleaning timer 113, and corresponds to the elapsed time. Set the cleaning conditions. The cleaning condition setting table is divided into cleaning ranks (strengths) corresponding to the elapsed time so that stronger cleaning is performed as the elapsed time is longer, and cleaning with the strength corresponding to the rank is set. When the cleaning intensity is determined, the rotation speed and rotation time of the suction pump 55 are set according to the intensity.

  The pressurizing condition setting unit 115 sets the pressurizing condition in the pressurizing process (ink pressurizing process) performed after the choke cleaning is completed as one process of the cleaning sequence. Parameters used when setting the pressurizing condition include cleaning conditions, standing time (cumulative elapsed time) after ink cartridge replacement, ink type, ink channel shape, temperature, and the like. The pressurizing process is a process of absorbing (re-dissolving) the fine bubbles generated in the ink by the pressure reduction during the chalk cleaning by increasing the ink pressure by the pressurization.

  The control unit 110 can access the nonvolatile memory 59 through the connection of the terminals 60 and 61. The non-volatile memory 59 stores information such as the remaining ink amount, the leaving time after ink cartridge replacement, and the ink type. Ink types include dye-based inks and pigment-based inks. In addition, the same dye-based inks are classified according to the ease of foaming of the ink. For example, organic solvent-based inks tend to foam more than water-based inks. Further, it is classified according to the ease of foaming depending on the kind and amount of additives such as surfactants added in the ink.

  The ink remaining amount acquisition unit 116 includes an ink consumption counter that counts the number of ink ejections (number of ink droplets) ejected from the nozzles 20b of the recording head 20 based on print data (bitmap data) for each ink color, and ink. Using the count value counted by the consumption counter, ink consumption calculation processing for calculating the ink consumption is executed. The ink consumption is obtained as a weight (mass) by multiplying the number of ink ejections by a predetermined coefficient. In the present embodiment, the ink droplets ejected from the nozzles have three sizes, large, medium, and small. The number of ink ejections is counted by a counter for each size, and the counted number of ink ejections corresponds to the ink droplet size. The ink consumption for each size is obtained by multiplying the coefficient, and the ink consumption for each color is calculated by adding the ink consumption for each size. The ink consumption counter also counts the number of ink ejections during flushing.

  Further, the ink consumption amount due to the cleaning is obtained from the driving rotation speed and driving time of the suction pump 55. The ink consumption by cleaning may be obtained by referring to table data indicating the relationship between the cleaning condition and the ink consumption. The ink remaining amount acquisition unit 116 adds the ink consumption obtained from the count value of the number of ink ejections and the cleaning ink consumption to obtain the total ink consumption. Then, the current remaining ink amount is obtained by sequentially subtracting the calculated total ink consumption amount from the remaining ink amount read from the nonvolatile memory 59 of the ink cartridge 23 when the printer 11 is turned on. Then, when the printer 11 is powered off, the current ink remaining amount temporarily stored in the RAM is written in the nonvolatile memory 59 on the ink cartridge 23 side. The ink remaining amount calculated by the ink remaining amount acquiring unit 116 is used to determine the target rotational speed (target drive amount) of the pressure pump motor 41 as described above.

  The time measuring unit 117 measures the elapsed time when the printer 11 is turned on and the elapsed time while the printer 11 is turned off. Then, when the printer 11 is turned on, the elapsed time measured while the power is turned off is added to the time left when the ink cartridge was replaced when the power was turned off, which was read from the nonvolatile memory 59, and the current time left. Ask. When the power is turned on, every time a predetermined time is measured, the measured time is added to the left time, and the current left time is sequentially updated. Then, when the power is shut off, the current leaving time is written in the nonvolatile memory 59.

  The memory in the controller 62 also stores ink flow path shape data, which is one of parameters for the pressurization condition setting unit 115 to determine the pressurization conditions. The shape of the ink flow path varies depending on the model of the printer 11 and the like. When the ink supply flow path is bent (for example, L-shaped), for example, more straight than the straight shape, there are more causes of foaming such as ink colliding with the flow path wall surface. The shape data is classified according to the ease of foaming of ink. Further, the printer 11 is provided with a temperature sensor (not shown), and the control unit 110 grasps the ink temperature in the ink supply flow path based on the temperature detection value input from the temperature sensor. Even if the temperature sensor is for detecting the environmental temperature, the environmental temperature may be regarded as the ink temperature. Even when the temperature sensor detects the heat generation of the motor, the detected temperature can be regarded as the environmental temperature when the printer 11 is turned on, and can be used as the ink temperature. This temperature is also one of the parameters for determining the pressurizing condition, and is divided into a plurality of stages including three or more stages including low temperature, medium temperature, and high temperature, for example. Based on this temperature parameter, it is determined that the higher the temperature, the easier the ink bubbles.

Next, a cleaning sequence executed by the controller 62 will be described.
The cleaning sequence is performed by the microcomputer 100 in the controller 62 executing the cleaning sequence program shown in the flowchart of FIG. 9 stored in the memory. FIG. 7 is a graph showing the relationship between the ink pressure and the elapsed time in the cleaning sequence execution process. FIG. 8 shows how the bubbles in the filter chamber 48a change during the course of the cleaning sequence.

  As shown in FIG. 7, in the cleaning sequence, “main suction” is first performed to perform chalk cleaning. Next, after the choke cleaning is completed, a “pressurizing process” is performed in which the ink pressure in the ink supply channels 24, 47, 78 between the ink cartridge 23 and the recording head 20 is increased. Finally, “trace suction” is performed to suck a small amount of ink from the nozzle 20b. Such a cleaning sequence is performed by the following control by the controller 62. The ink pressure change and the change of bubbles in the ink supply channel (for example, the filter chamber 48a) will be described with reference to FIGS. 7 and 8 together with the cleaning sequence. In addition, the ink pressure in the graph of FIG. 7 shows the ink pressure of the filter chamber 48a in FIG. 8, for example.

  For example, if the elapsed time counted by the cleaning timer 113 when the printer 11 is turned on exceeds a predetermined time required for choke cleaning, the control unit 110 instructs the cleaning condition setting unit 114 to set the cleaning condition. The cleaning condition setting unit 114 refers to the cleaning condition table based on the time measured by the cleaning timer 113 and sets the cleaning condition according to the elapsed time at that time. The rotation speed and rotation time of the suction pump 55 are set by setting the cleaning conditions. Even when the user operates the cleaning switch, the cleaning condition setting unit 114 sets the cleaning condition based on a command from the control unit 110. In any case, the cleaning condition set is choke cleaning (step S1).

  Next, as a preparation for choke cleaning, the air chamber 43 of the ink cartridge 23 is opened to the atmosphere, and the ink pressurization supply from the ink cartridge 23 is stopped. That is, the controller 110 reversely drives the pressurizing pump motor 41 to switch the air release valve 28 from the closed state to the open state, thereby opening the air chamber 43 to the atmosphere (step S2). When the air chamber 43 is opened to the atmosphere, the ink pack 23b is not pressurized, and the ink pressurization supply from the ink cartridge 23 is stopped. However, if the air chamber 43 is in an open air state before the pressurization pump device 25 is still driven when the printer 11 is turned on, this process is omitted.

  Next, the control unit 110 drives the electric motor 53 to rotate forward, and raises the cap 32 via the lifting mechanism 52. As a result, the cap 32 is disposed in a capping state (the state shown in FIGS. 2 and 3) that contacts the nozzle opening surface 20a of the recording head 20 so as to surround the nozzle 20b (step S3). In the capping, when the carriage 15 is at a position away from the home position, the controller 110 drives and controls the carriage motor 18 to place the carriage 15 at the home position, and then the capping is performed. Of course, this process is omitted when the power is turned on or when the printing is suspended, and when it is already in the capping state.

  In this state, the electromagnetic open / close valve 35 is in a closed state. Further, when the maintenance device 31 includes an air release valve for opening the cap 32 to the atmosphere, the air release valve is in a closed state. In this state, chalk cleaning is performed (step S4). Choke cleaning is performed as follows. The controller 110 drives the suction pump motor 56 at a drive speed and drive time corresponding to the suction pump 55 so as to drive the suction pump 55 at a rotation speed and a rotation time corresponding to the conditions set by the cleaning condition setting unit 114. The suction pump 55 rotates in the direction of the arrow in FIG. 2, and the roller 69 rotates while crushing the intermediate portion 54 a of the discharge tube 54, so that negative pressure is introduced into the cap 32.

  As a result, ink is sucked from the nozzle 20b of the recording head 20, and the ink in the pressure chamber 89 of the pressure reducing valve 46 begins to decrease. Then, when the pressure in the pressure chamber 89 of the pressure reducing valve 46 becomes equal to or lower than a predetermined pressure, the pressure reducing valve 46 is opened. As a result, the ink flows into the pressure chamber 89 of the pressure reducing valve 46, and the ink that has flowed in flows out of the valve chamber 76 of the choke valve 45 located on the upstream side. During this choke suction, the ink introduced from the ink supply flow path 24 (tube) is in a non-pressurized state and the ink in the valve chamber 76 begins to decrease.

  In the choke valve 45 in the valve open state shown in FIG. 4A, the film 75 is bent inwardly of the valve chamber 76 due to the pressure reduction accompanying the ink decrease in the valve chamber 76, and is in close contact with the protrusion 73. Close the valve. Even after the valve is closed, ink is continuously sucked from the nozzle 20b, so that the negative pressure is sufficiently accumulated in the ink supply channel 47 from the closed position of the choke valve 45 to the nozzle 20b of the recording head 20 ( Decompression step). Then, under a reduced pressure state in which the negative pressure is sufficiently accumulated, the control unit 110 starts driving the pressurizing pump motor 41 and starts driving the pressurizing pump 42.

  As a result, the sending of the pressurized air from the pressure pump 42 is resumed, and the ink is pressurized and supplied from the ink cartridge 23 to the valve unit 21. When ink is pressurized and supplied to the valve chamber 76 through the introduction path 72 of the choke valve 45, the film 75 is separated from the projection 73 and the choke valve 45 is opened.

  By opening the choke valve 45, in order to eliminate the negative pressure accumulated in the valve chamber 76 and the flow path on the downstream side, the ink flows from the upstream side at once, and the ink whose flow velocity is instantaneously increased flows. . As a result, bubbles and foreign matter staying in the valve chamber 76 and the ink supply flow paths 47 and 78 downstream thereof are discharged from the nozzle 20b of the recording head 20 together with the ink (discharge stage). Thereafter, when the drive time of the suction pump 55 reaches a preset total drive time, the drive of the suction pump motor 56 is stopped. Thus, the “main suction” (choke cleaning) shown in the graph of FIG. 7 is completed.

  By this chalk cleaning, as shown in FIG. 8 (a), the bubbles B1 captured by the filter 49 in the filter chamber 48a before the cleaning, as shown in FIG. Attempts to pass through the filter 49 while expanding greatly due to the reduced pressure. At this time, microbubbles B2 are deposited in the ink 50 due to the reduced pressure.

  Then, when the choke valve 45 is opened by the pressure of the pressurized ink sent from the upstream side when the pressure pump 42 is re-driven while the bubble B1 is greatly expanded, as shown in FIG. The air bubbles B1 are removed from the filter 49 by the ink that has flowed downstream at the same time, are pushed downstream, and are discharged from the nozzle 20b all at once. At this time, the bubble B1 that has expanded due to the reduced pressure is reliably removed from the filter 49 because it receives a large resistance from the ink.

  Then, as shown in FIG. 8D, the microbubbles B2 remain in the ink 50 immediately after the completion of the chalk cleaning. The microbubbles B2 disappear with time, but in order to disappear to such an extent that printing can be performed, for example, a waiting time of 5 minutes or more is required. In this embodiment, in order to quickly disappear the microbubbles B2, the “pressurizing process” shown in FIG. 7 is performed after the completion of the chalk cleaning in the cleaning sequence.

  When the suction pump 55 is driven at a rotation speed and a rotation time according to the set cleaning conditions, the control unit 110 stops driving the suction pump motor 56 and ends the choke cleaning. When the driving of the suction pump 55 is stopped, the inside of the cap 32 is opened to the atmosphere, and the pressure reducing valve 46 is closed.

  Thereafter, the idle suction in step S5 in FIG. 9 is performed. That is, after the inside of the cap 32 is opened to the atmosphere, the control unit 110 restarts the driving of the suction pump motor 56 and discharges the ink staying in the cap 32 to the outside of the cap 32 without sucking ink from the nozzle 20b. . Note that the air release in the cap 32 can be achieved by moving the cap 32 to the retracted position and separating it from the nozzle opening surface 20a, or by opening the air release valve in the case of the maintenance device 31 having the air release valve. Do.

  When a predetermined idle suction time has elapsed from the start of driving of the suction pump 55 or the rotation of the predetermined number of rotations is completed, the control unit 110 stops driving the suction pump 55. At this time, the control unit 110 grasps the rotational position of the suction pump 55 based on the detection signal from the rotational position sensor 63, and the suction pump motor stops so that the roller 69 stops at a position where the roller 69 avoids the leak point LP. 56 is stopped (step S7). As a result, as shown in FIG. 2, the suction pump 55 stops in a state where the roller 69 crushes the intermediate portion 54 a of the discharge tube 54, and communication with the atmosphere through the discharge tube 54 in the cap 32 is blocked. The After the idle suction, the nozzle opening surface 20a is wiped with the wiper 33 to wipe off the adhered ink, and the ink meniscus in the nozzle 20b is adjusted. After the wiping is completed, the cap 32 that has been lowered for wiping or idle suction is raised and placed at the capping position.

  In this state, the pressurizing process is started. First, in step S7 in FIG. 9, a pressurizing condition in the pressurizing process is set. That is, the pressurizing condition setting unit 115 sets the pressurizing condition. As described above, the parameters for determining the pressurizing condition include the cleaning condition, the leaving time (cumulative elapsed time) after the ink cartridge replacement, the ink type, the ink flow path shape, the temperature, and the like. These are all parameters that affect the precipitation of the microbubbles B2, and the stronger the parameter value tends to promote the precipitation of the microbubbles B2 (that is, the more easily bubbles are generated), the stronger The pressurizing condition for performing a proper pressurizing process is set.

  As shown in the graph of FIG. 7, the pressure Px (target pressure) and the pressure holding time Tx in the pressure processing are set according to the strength of the pressure processing determined according to these parameters. For example, if the microbubbles B2 are difficult to precipitate (parameter value), a weak pressurizing condition is set, for example, the pressurizing pressure Px is a normal value, and the pressurization holding time Tx is set shorter than normal. On the other hand, if the microbubbles B2 are likely to precipitate, a strong pressurizing condition is set, for example, the pressurizing pressure Px is a normal value, and the pressurization holding time Tx is set longer than normal.

  Here, the relationship between each parameter and the pressurizing condition will be described. First, regarding the parameters of the cleaning condition, the pressure holding time Tx is increased as the cleaning condition has a lower maximum ultimate pressure during choke cleaning (a larger absolute value of the negative pressure value) according to the cleaning condition set by the cleaning condition setting unit 114. And set the pressure Px strong. In the cleaning conditions, the cleaning time (suction pump rotation time) and the cleaning strength (suction pump rotation speed) are set. The longer the cleaning time, the longer the pressure holding time Tx, and the stronger the cleaning, the higher the pressure. The holding time Tx is set longer. Further, the pressurizing force Px is increased as the cleaning time is longer, and the pressurizing force Px is increased as the cleaning is stronger.

  Regarding the ink type parameter, the pressure type holding time Tx is set longer and the pressure Px is set stronger as the type of ink is more likely to generate bubbles. For example, organic solvent-based inks tend to foam more easily than water-based inks, and the greater the amount of surfactant added, the more likely to foam, and the ease of foaming also depends on the type of pigment-based ink and dye-based ink. The types are divided.

Regarding the parameters of the ink flow path shape, the pressure holding time Tx is set longer and the pressure Px is set stronger as the ink flow path shape is more complicated.
As for the parameter of the leaving time, the longer the holding time after the ink cartridge 23 is replaced with a new ink cartridge 23 (after the ink pack 23b is opened), the longer the pressure holding time Tx and the stronger the pressure Px are set. To do. Here, the ink pack 23b in the ink cartridge 23 is filled with degassed ink that has been degassed. Although the deaerated ink has a function of absorbing bubbles, the degree of deaeration decreases with the passage of time from the time when the ink pack 23b is opened (when the ink cartridge is replaced), and the bubble absorbing ability decreases. While the degree of deaeration is high, the bubble absorbing ability is also high, so that the pressurization holding time Tx necessary for eliminating the microbubbles B2 can be shortened. For this reason, the degree of decrease in the degassing degree is managed by the leaving time after the ink cartridge replacement, and the longer the leaving time is and the lower the degassing degree is, the longer the pressure holding time Tx and the stronger the pressure Px are set.

As for the temperature parameter, the higher the temperature, the longer the pressurization holding time Tx and the stronger the pressure Px.
The pressurization condition setting unit 115 acquires the cleaning condition from the cleaning condition setting unit 114, the ink type from the nonvolatile memory 59, the standing time from the time measuring unit 117, and the temperature from the detection value of the temperature sensor. Based on each parameter, the pressurization condition for the pressurization process is set with reference to the pressurization condition setting table read from the memory. The pressurization condition setting table is created so that the pressurization holding time Tx is longer and the pressurizing force Px is set stronger as the parameter value is more likely to generate bubbles.

  In the present embodiment, both the applied pressure Px and the pressurization holding time Tx are changed according to the strength (rank) of the pressure condition determined according to the parameter. Of course, the pressurizing pressure Px may always be kept constant and only the pressurizing and holding time Tx may be changed. Conversely, the pressurizing and holding time Tx may be always kept constant and only the pressurizing pressure Px may be changed. As a method in which the pressurization condition setting unit 115 sets the pressurization condition by referring to the pressurization condition setting table based on a plurality of parameters, for example, the strength (rank) of the pressurization condition is checked for each parameter, The setting method which selects high pressurization conditions is mentioned. Alternatively, the pressurization condition may be set by referring to the pressurization condition setting table based on the sum of values obtained by multiplying each parameter by the weighting coefficient for each parameter. In this manner, the pressurizing condition for the pressurizing process is set based on the values of parameters such as the cleaning condition, the standing time, the ink type, the ink flow path shape, and the temperature.

  When the pressurization condition is set in this way, the pressurization pump motor 41 is driven to drive the pressurization pump 42 to perform pressurization processing under the set pressurization condition next (step S8), and then The electromagnetic opening / closing valve 35 is opened (step S9). Then, it is determined whether or not the pressure has been increased to the target pressure Px (step S10). If the pressure is not increased to the target pressure Px, the pressure pump 42 is increased until the pressure is increased to the target pressure Px. Continue driving. Then, when the pressure is increased to the target pressure Px, the driving of the pressurizing pump motor 41 is stopped and the driving of the pressurizing pump 42 is stopped (step S11).

  Then, as shown in FIG. 7, when the target pressure Px is reached, the timer 112 starts measuring the pressurization holding time Tx. Then, it is determined whether or not the pressurization holding time Tx has elapsed (step S12). If the pressurization holding time Tx has not elapsed, the pressurization state is held until the timer 112 finishes measuring the pressurization holding time Tx and waits. When the timer 112 finishes measuring the pressurization holding time Tx, the electromagnetic on-off valve 35 is closed and the cap 32 is opened to the atmosphere (step S13). As a result, the ink pressurization state downstream of the pressure reducing valve 46 is released. As described above, by releasing the atmosphere only in the cap 32, the pressurized air pressure in the air chamber 43 is used for supplying ink pressure during subsequent printing. Of course, the air release at the end of the pressurizing process may be performed by opening the air release valve 28. In this case, the electromagnetic on-off valve 35 is kept in the open state until at least the air release in the cap 32 is completed. Is done. The stage (S8 to S13) after the pressurization process is started and maintained at the target pressure Px until the atmosphere is released corresponds to the pressurization stage.

  By this pressurization process, as shown in FIG. 8 (d), the microbubbles B2 present in the ink 50 immediately after the completion of the choke cleaning cause the ink pressure to increase due to the pressurization process as shown in FIG. 8 (e). As a result, the ink 50 is quickly dissolved again and disappears. For example, when waiting until the microbubbles B2 are naturally extinguished, the time required for cleaning from the start of cleaning to the state where printing can be started takes, for example, 5 minutes or more. On the other hand, when the pressure treatment is performed, the time required for the cleaning until the microbubbles B2 disappear and the printing can be started even when the same air pressure is applied as when ink is supplied under pressure other than cleaning is as follows. For example, it is shortened to about 30 seconds. For this reason, even if a relatively strong choke cleaning is performed and a large number of microbubbles B2 are deposited, printing can be started immediately thereafter.

  When the pressurizing process is completed, a small amount of suction is then performed (step S14). This minute suction is performed in order to discard the ink mixed in the nozzle because the ink discharged by the chalk cleaning jumps at the cap 32 and adheres to the nozzle opening. Conventionally, since the micro-aspiration is performed mainly for discharging the microbubbles B2, the micro-aspiration can be abolished. However, in the case of applying a pressing force that destroys the ink meniscus in the nozzles during the pressurizing process, it is preferable to perform a slight amount of suction in order to realign the ink meniscus.

  Then, after the micro-aspiration is completed, the idle suction is performed again, and thereafter, the nozzle opening surface 20a is wiped with the wiper 33, the adhered ink is wiped off, and the ink meniscus in the nozzle 20b is adjusted.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) Since the ink in the ink supply channels 24, 47, and 78 is pressurized after completion of the chalk cleaning, the microbubbles B2 precipitated by the reduced pressure during the chalk cleaning can be absorbed (re-dissolved) in the ink. For this reason, printing can be started promptly without providing a waiting time until the microbubbles naturally disappear after completion of chalk cleaning. Further, it is possible to enhance the cleaning effect by performing strong chalk cleaning in which the microbubbles B2 are deposited. Further, it is possible to eliminate the micro-aspiration that is again performed to remove the micro-bubbles B2. Therefore, the microbubbles B2 deposited during the chalk cleaning can be eliminated at an early stage while minimizing ink consumption. As a result, it is possible to achieve both bubble discharge and printing stability.

  (2) A positive pressure is applied to the nozzle 20b to increase the ink pressure in the ink supply channel 47 on the downstream side of the pressure reducing valve 46. Therefore, the positive pressure suppresses the leakage of ink from the nozzle 20b, and the ink in the ink The microbubbles B2 can be quickly eliminated. For this reason, the ink consumption at the time of a pressurizing process can be suppressed little.

  (3) Although the pressure reducing valve 46 has a self-sealing configuration that does not open by pressurization regardless of the upstream side or the downstream side, ink is supplied from both the upstream side and the downstream side with the pressure reducing valve 46 interposed therebetween. Since the ink in the supply channels 24, 47, and 78 is pressurized, the area on the downstream side of the choke valve 45 that has been depressurized during choke cleaning can be pressurized throughout, and the microbubbles B2 can be effectively eliminated. By pressurization from the nozzle 20b side, the microbubbles B2 existing in a place where bubbles are likely to stay, such as the filter chamber 48a located downstream of the pressure reducing valve 46, can be quickly eliminated.

  (4) The pressurized air supplied into the cap 32 from the pressure pump device 25 can pressurize the ink in the ink flow path through the nozzle openings. Thus, in order to pressurize the ink supply channel 47 on the downstream side of the pressure reducing valve 46, the nozzle 20b is used as a pressure application site of pressurized air. For this reason, it is not necessary to provide this type of pressure application site on the recording head 20, the carriage 15, or the like. Further, the cap 32, which is a component part of the suction means, is used as a part of the pressurizing means. Therefore, the number of configurations to be added or changed when providing the pressurizing unit is small.

  (5) A pressurizing tube 34 for supplying pressurized air from the pressurizing pump 42 to the cap 32 is provided, and an electromagnetic opening / closing valve 35 is provided in the middle of the pressurizing tube 34. As a result, by closing the electromagnetic open / close valve 35 during choke cleaning, it is possible to prevent the ink sucked from the nozzle 20b from flowing backward from the cap 32 to the pressure tube 34 side (or the pressure pump 42 side). In addition, during the pressurizing process, by opening the electromagnetic on-off valve 35, the ink in the ink supply channel 47 can be pressurized from the nozzle 20b side, and the microbubbles B2 can be eliminated.

  (6) During the pressurization process, the intermediate portion 54a of the discharge tube 54 is pressed and closed by the roller 69 of the suction pump 55, so that the pressurized air supplied to the cap 32 is discharged using the function of the suction pump 55. Leakage via the tube 54 can be avoided. For this reason, it is not necessary to separately provide a closing means such as an electromagnetic valve in order to avoid this type of pressurized air leakage.

  (7) Further, the suction pump 55 has a structure in which the intermediate portion 54a of the discharge tube 54 is drawn in an Ω-shape, but the rotation position sensor 63 detects the rotation position of the suction pump 55, and the roller 96 leaks. The suction pump 55 is controlled to stop at a position avoiding the point LP. Therefore, even in the suction pump 55 where the leak point LP exists, the leak through the discharge tube 54 of the pressurized air can be reliably suppressed, and the pressurization process can be reliably performed.

  (8) Acquire conditions that affect the precipitation of microbubbles, and set the pressurizing conditions during the pressurizing process according to the acquired conditions, so that the microbubbles B2 that have precipitated in the ink during chalk cleaning can be more reliably detected. Can be eliminated.

  (9) According to the cleaning conditions set by the cleaning condition setting unit 114, the pressurization condition is set more strongly for the cleaning condition with a lower maximum pressure at the time of chalk cleaning. B2 can be eliminated more reliably and in a short time.

  (10) As the type of ink (type of fluid) is more likely to generate bubbles, the pressurization and holding time Tx is set longer, so that the microbubbles B2 generated in the ink in the ink flow path during chalk cleaning. Can be eliminated more reliably and in a short time.

  (11) Pressurization conditions are set more severely for conditions where the ink flow path shape is more complicated (L-shaped, etc.), so that the microbubbles B2 precipitated in the ink during chalk cleaning can be more reliably and in a short time. Can be eliminated.

  (12) Since the pressurization condition is set more severely as the leaving time is longer based on the condition (parameter) of the leaving time after the ink cartridge replacement, the fine bubbles B2 precipitated in the ink at the time of chalk cleaning can be more surely set. It can be eliminated in a short time.

  (13) The higher the temperature based on the temperature condition (parameter), the tighter the pressurization condition is set. Therefore, the microbubbles B2 precipitated in the ink at the time of chalk cleaning can be eliminated more reliably and in a short time. .

In addition, embodiment of invention is not limited to the said embodiment, You may change as follows.
(Modification 1) In the above embodiment, the self-sealing pressure reducing valve 46 is used as the pressure reducing valve provided in the middle of the ink supply flow path. However, for example, the valve opens when pressurized from the upstream side. A pressure reducing valve may be used. In this case, the point of pressurization from both the upstream side and the downstream side is the same as in the above embodiment, and the pressurizing pump 42 as the pressurizing source is the same, but the ink pack 23b is opened by opening the pressure reducing valve. The flow path from the ink outlet 23c to the nozzle 20b is in communication. For this reason, the air pressure in the air chamber 43 and the air pressure in the cap 32 extending to the nozzle 20b are balanced so that the working force from the ink pack 23b side and the working force from the nozzle 20b side are balanced against the ink in the flow path. And adjust. Since the force acting on the ink in the flow path is determined by the product of the air pressure and the pressure receiving area, the product of the pressure receiving area of the ink pack 23b and the air pressure of the air chamber 43, the total area of all the nozzles 20b, and the air pressure in the cap. Each air pressure in the air chamber 43 and the cap 32 is adjusted so that the product of For example, an electromagnetic pressure adjusting valve is provided on the flow path between the pressurizing pump 42 and the ink cartridge 23, and the pressure applied from the upstream side is reduced by controlling the electromagnetic pressure adjusting valve to adjust the upstream side and the downstream side. The force acting on the ink is balanced by pressurizing from the ink. In this way, ink does not leak from the nozzle 20b, and bubbles due to the pressurized air do not enter the nozzle 20b. However, if the pressure from the downstream side is applied first in time, the pressurized air flows from the nozzle 20b, causing air bubbles to flow into the ink. Therefore, it is preferable to control the opening timing of the electromagnetic on-off valve 35 so that the pressurization timing to the nozzle 20b is slightly delayed. Further, both pressures may be adjusted so that the force from the upstream side is slightly stronger than the force from the downstream side, and the inflow of pressurized air from the nozzle 20b may be suppressed. In these cases, although some ink leaks from the nozzle 20b, the inflow of bubbles due to the pressurized air from the nozzle 20b is suppressed.

  (Modification 2) Although it was set as the structure which prevents the leak of pressurized air using the function of the suction pump 55 by pressing the intermediate part 54a with the roller 69 and obstruct | occluding the discharge tube 54, it changes to this, A configuration in which an electromagnetic on-off valve is provided in the middle of the discharge tube 54 and the leak of the pressurized air through the discharge tube 54 can be prevented by closing the electromagnetic on-off valve.

  (Modification 3) In the above embodiment, the pressure is applied from both the upstream side and the downstream side. However, in the configuration in which the self-sealing pressure reducing valve 46 is provided on the ink flow path, the pressure is applied only from the downstream side. A configuration can also be adopted. Even if the pressure is applied only from the downstream side, the ink does not flow to the upstream side from the pressure reducing valve 46. Therefore, the ink between the pressure reducing valve 46 and the nozzle 20b can be pressurized. The minute bubbles B2 remaining in the ink in the filter chamber 48a positioned on the ink supply channel 47 between them can be eliminated. Further, when pressurization is performed from both the upstream side and the downstream side, in a configuration in which the pressure reducing valve 46 is provided, the respective pressurizing forces may be different in both directions. For example, the nozzle 20b side may be set to a pressure that can reliably avoid the inflow of pressurized air into the nozzle 20b. In this way, even in the configuration in which only the downstream side between the pressure reducing valve 46 and the nozzle 20b is pressurized, for example, the ink in the vicinity of the nozzle 20b and the ink chamber 20c has a relatively short time after printing is started thereafter. Since it is injected into the inside, there is a possibility that microbubbles remain before being injected. However, there is a high possibility that the microbubbles in the upstream ink that have time to be ejected naturally disappear within the time required for the subsequent ejection. For this reason, even when the pressure is applied only to the downstream portion communicating with the nozzle 20b, the print quality is maintained well.

  (Modification 4) Pressurization from the downstream side is not limited to a configuration in which pressurized air (pressurized gas) is supplied into the cap 32 and the ink is pressurized through the nozzle 20b. For example, a seal member is brought into intimate contact with the nozzle opening surface 20a of the recording head 20 to seal all the nozzle openings, and under this sealing state, ink other than the nozzles 20b is used as a pressurizing application site to add ink in the ink supply flow path. The structure to press can be adopted. For example, a pressurizing chamber is provided outside the film 88 (diaphragm) of the pressure reducing valve 46. Normally, the pressurizing chamber is opened to the atmosphere by opening the valve, and during the pressurizing process, the valve is closed to communicate with the atmosphere. After shutting off, the pressurization valve connected to the pressurization chamber is opened to send the pressurized air from the pressurization pump 42 to the pressurization chamber, and the film 88 and the pressure receiving plate 90 of the decompression valve 46 are externally moved. A configuration in which pressure is applied to pressurize the ink in the ink supply channel 47 can also be employed. Furthermore, the method of pressurizing the film 88 and the pressure receiving plate 90 with this configuration is not limited to pressurized air. For example, pressure may be applied by pressing the pressure receiving plate with a pressing member. Examples of the pressing member include a configuration that mechanically presses using an actuator such as a small piston or solenoid, and a configuration that presses the pressure receiving plate 90 with a spring. In addition, the configuration in which the film 88 of the pressure reducing valve is pressurized from the outside includes a configuration in which pressurized air is supplied through a flexible tube that can follow the movement of the carriage, and when the carriage reaches the home position, For example, a configuration in which the communication port is in contact with the contact member to seal the outer chamber of the film 88 and pressurized air is supplied to each chamber through the contact member. Further, when the carriage reaches a predetermined position outside the printing area, it is possible to employ a configuration in which each diaphragm is pressed by the corresponding pressing member to pressurize the ink in the ink supply channel 47. Any of these configurations can pressurize the ink in the ink supply flow path 47 between the valve unit 21 and the nozzle 20b. For example, pressurize the ink in the filter chamber 48a located downstream of the valve unit 21. it can. Further, a similar diaphragm structure can be provided at a location other than the diaphragm of the pressure reducing valve, and the ink can be pressurized by pressing a diaphragm provided at a predetermined location on the ink supply channel 47 other than the pressure reducing valve. For example, a diaphragm is provided on the side surface of the recording head 20 or the side surface of the carriage 15 where pressure can be applied to the ink supply channel 47 passing through the inside, and the ink in the ink supply channel 47 is pressurized by pressurizing the diaphragm with pressurized air. The structure which pressurizes can also be employ | adopted.

  (Modification 5) In the above embodiment, the pressure of the air chamber 43 is adjusted by driving the pressurizing pump by the number of rotations corresponding to the volume of the air chamber 43 obtained from the remaining ink amount (ink pack volume). You may provide the pressure sensor which can detect the pressure of an air chamber. In this case, the pressure pump 42 is driven until the pressure sensor reaches a predetermined pressure value. What is necessary is just to provide a pressure sensor in the middle of the flow path between the pressurization pump 42 and the air release valve 28, for example. In addition, when setting the pressurizing conditions (pressurization holding time and pressurizing force) according to the conditions (parameters) that apply to the choke cleaning and indicate the ease of bubble deposition, May be determined based on the detection value of the pressure sensor.

  (Modification 6) The choke valve 45 is not limited to a differential pressure valve. An electromagnetic opening / closing valve may be used as the choke valve 45. If the electromagnetic on-off valve is closed during the choke suction process (negative pressure accumulation stage) and the electromagnetic on-off valve is opened during the pressurization and discharge process, the choke cleaning can be similarly performed.

  (Modification 7) The suction means is not limited to a configuration using a cap. For example, a recording head is provided in a chamber (chamber), a valve on a communication path that communicates the chamber with the atmosphere outside the chamber is closed, and the chamber is sealed off from the atmosphere. A configuration in which a suction force is exerted on the nozzles of the recording head by driving a suction pump connected through a suction path to introduce a negative pressure into the chamber can be employed. Thus, the suction unit can employ an appropriate configuration as long as it can exert a suction force on the nozzle.

  (Modification 8) As the ink supply system, a water head type that supplies ink from the ink cartridge 23 by a water head difference can be adopted. That is, the ink outlet portion 23 c of the ink cartridge 23 is disposed above the valve unit 21 in the gravity direction, and the ink in the ink pack 23 b passes through the ink supply channel 24 due to the positive pressure based on the water head difference generated thereby. This configuration is supplied to the valve unit 21. Even in this configuration, if the configuration is such that the ink in the ink cartridge is pressurized with air pressure, the ink in the ink supply channel can be pressurized from the upstream side by supplying pressurized air into the ink cartridge during the pressurizing process. it can. Further, the ink may be pressurized at a predetermined location downstream of the ink cartridge, instead of being configured to pressurize the inside of the ink cartridge. For example, an electromagnetic open / close valve is provided in the middle of the flow path between the ink cartridge and the differential pressure valve, and with the electromagnetic open / close valve closed, the diaphragm of the differential pressure valve is pressurized or pressed from the outside in the ink supply flow path. The structure which pressurizes the ink of this is mentioned.

  (Modification 9) Although the printer 11 is a serial printer having a carriage 15, it has a carriage, and there are a plurality of fluid ejecting heads in a row or a long shape over the maximum width of the print medium. The cleaning device of the present invention may be employed in a fluid ejecting apparatus (for example, a line printer) having a single full line head.

(Modification 10) In the above-described embodiment, the fluid ejecting apparatus is embodied as an ink jet recording apparatus. However, the present invention is not limited to this, and fluid other than ink (liquid or functional material particles are dispersed or mixed in the liquid). And a fluid ejecting apparatus that ejects or ejects a liquid or a fluid such as a gel. For example, a liquid material ejecting apparatus that ejects a liquid material that is dispersed or dissolved in materials such as electrode materials and color materials (pixel materials) used in the manufacture of liquid crystal displays, EL (electroluminescence) displays, and surface-emitting displays. Further, a liquid ejecting apparatus that ejects a bio-organic matter used for biochip manufacturing, or a liquid ejecting apparatus that ejects a liquid that is used as a precision pipette and serves as a sample may be used. 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, a liquid ejecting apparatus that ejects an etching solution such as acid or alkali to etch the substrate, and a fluid ejecting apparatus that ejects a fluid such as a gel (for example, a physical gel) It may be. And this invention is applicable to the maintenance apparatus of any one of these fluid ejecting apparatuses. In the present specification, the “fluid” includes, for example, a liquid (including an inorganic solvent, an organic solvent, a solution, a liquid resin, a liquid metal (metal melt), etc.), a liquid, and a fluid.

  (Modification 11) Further, the fluid may be a gas. For example, even if liquid is attached or accumulated in the fluid supply flow path, the gas generated by evaporation of the liquid when the pressure is reduced by choke cleaning in order to suck and discharge foreign matter (for example, liquid) in the fluid The foreign substance can be liquefied and disappeared by pressurizing the fluid in the fluid supply channel by the pressurizing means. For this reason, even if the fluid is ejected promptly from the fluid ejecting head, it is possible to effectively avoid the mixture of gaseous foreign substances in the ejected fluid.

Hereinafter, the technical idea grasped | ascertained from the said embodiment and each modification is described.
(1) The negative pressure generating means is a tube pump, and has a rotating body (69) that can rotate while crushing the tube (54a) in the tube pump, and the rotating body can press the tube. And a retracted position that does not press the tube, and the closing means places the rotating body at the pressing position when the pressurizing means pressurizes. Cleaning device for fluid ejecting apparatus.

  According to this, at the time of pressurizing by the pressurizing means, the tube pump is pressed and closed by the rotating body of the tube pump, thereby utilizing the function of the tube pump that generates a negative pressure for choke cleaning, to the cap 32. It is possible to avoid leakage of the supplied pressurized fluid via the discharge flow path on the tube pump side. For this reason, it is not necessary to separately provide a closing means.

  (2) The invention according to any one of claims 1 to 8, further comprising a control unit that controls at least the suction unit, the pressurizing unit, and the pressurizing source, wherein the control unit includes the pressurizing unit. Is controlled so as to simultaneously pressurize the fluid from the fluid supply source and pressurize the fluid from the nozzle.

  (3) The invention according to any one of claims 1 to 8, further comprising a control unit that controls at least the suction unit, the pressurizing unit, and the pressurizing source, wherein the control unit includes the pressurizing unit. Is controlled so as to start pressurizing the fluid from the nozzle behind the pressurization of the fluid from the fluid supply source. According to this, inflow of the fluid (for example, gas) for pressurization from a nozzle can be prevented.

  (4) The condition acquisition means is a cleaning condition setting means for setting a cleaning condition, and the pressurizing means increases the pressurization holding time as the cleaning time increases in accordance with the cleaning condition, and the cleaning is performed. The cleaning device for a fluid ejecting apparatus according to claim 8, wherein the pressure holding time is set longer as the strength increases. According to this, the longer the cleaning time is, the longer the pressurization holding time is set, and the stronger the cleaning is, the longer the pressurization holding time is set. Therefore, bubbles generated in the fluid in the fluid supply channel at the time of cleaning Can be more reliably eliminated.

  (5) The condition acquired by the condition acquiring unit is a type of fluid supplied to the fluid ejecting unit, and the pressurizing unit is set in advance according to the type of fluid that bubbles are likely to be generated. The cleaning device for a fluid ejecting apparatus according to claim 7, wherein when the fluid is a kind of fluid, the pressurization holding time is set to be long. According to this, as the type of fluid is more likely to generate bubbles, the pressurization and holding time is set longer, so that bubbles generated in the fluid in the fluid supply channel during cleaning are more reliably lost. Can be made.

  (6) The condition acquired by the condition acquisition means is a condition of a flow path shape that connects the fluid supply source and the fluid ejection means, and the pressurization means is a condition that the flow path shape is complicated. The cleaning device for a fluid ejecting apparatus according to claim 7, wherein the pressurization holding time is set longer as the pressure is increased. According to this, since the pressure holding time is set longer as the flow path shape is more complicated, bubbles generated in the fluid in the fluid supply flow path can be more reliably eliminated during cleaning. .

  (7) The condition acquired by the condition acquisition means is a condition of a standing time after the fluid supply source is opened, and the pressurizing means has a longer standing time based on the condition of the leaving time, The cleaning device for a fluid ejecting apparatus according to claim 7, wherein the pressurization holding time is set long. According to this, since the pressurization holding time is set longer as the leaving time is longer based on the condition of the leaving time, the bubbles generated in the fluid in the fluid supply flow path can be more surely eliminated during cleaning. it can.

  (8) The condition acquired by the condition acquiring unit is a temperature condition, and the pressurizing unit sets the pressurization holding time longer as the temperature is higher based on the temperature condition. The cleaning device in the fluid ejecting apparatus according to claim 7. According to this, as the temperature is higher based on the temperature condition, the pressurization holding time is set longer, so that the bubbles generated in the fluid in the fluid supply channel during cleaning can be more reliably eliminated.

  (9) The fluid ejected from the nozzle by the fluid ejecting head is any of a liquid, a liquid material, and a fluid (gel, etc.), and the pressurized fluid that the pressurizing means supplies for pressurization is The cleaning device for a fluid ejecting apparatus according to any one of claims 1 to 8, wherein the pressurized gas is a pressurized gas, and the technical ideas (1) to 8.

FIG. 2 is a plan view illustrating a schematic configuration of a recording apparatus according to the present embodiment. The side view which shows the suction pump in a cleaning apparatus. The schematic diagram which shows the electric constitution and fluid pressure circuit of a cleaning apparatus. (A) (b) Sectional drawing which shows a choke valve. (A) (b) Sectional drawing which shows a pressure-reduction valve. FIG. 2 is a block diagram illustrating an electrical configuration of the printer. The graph which shows the mode of the fluid pressure change in the cleaning sequence execution process. (A)-(e) The schematic cross section explaining chalk cleaning and pressurization processing. The flowchart which shows a cleaning sequence.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Recording apparatus as fluid ejecting apparatus, 15 ... Carriage, 18 ... Carriage motor, 20 ... Recording head as fluid ejecting means, 20a ... Nozzle opening surface, 20b ... Nozzle, 21 ... Valve unit, 23 ... Ink cartridge, 24 ... Ink supply flow path constituting fluid supply flow path, 25 ... Pressure pump device, 27 ... Pressure tube, 29 ... Air supply tube, 32 ... Cap constituting suction means and pressure means, 34 ... Pressure means And a pressurizing tube as a pressurizing fluid supply flow path, 35... A pressurizing means and an electromagnetic on-off valve as an on-off valve, 41... A pressurizing pump motor constituting the pressurizing means, 42. Pressurizing pump constituting means, 45... Choke valve as blocking valve, 46. Pressure reducing valve, 47. Ink supply passage constituting fluid supply passage, 48. 48a ... filter chamber, 49 ... filter, 51 ... discharge drive element, 53 ... electric motor, 54 ... discharge tube as discharge flow path, 55 ... suction pump constituting suction means and negative pressure generating means, 56 ... suction Suction pump motor constituting means and negative pressure generating means, 59... Non-volatile memory constituting condition obtaining means, 62. Controller as control means, 63... Rotational position sensor, 69. Ink supply flow path constituting the supply flow path, 89... Pressure chamber as a valve chamber, 100... Microcomputer, 102 to 104... Motor drive circuit, 105 ... Valve drive circuit, 110. Control unit 111... Operation unit 112 112 timer 113 cleaning timer 114 condition acquisition means and cleaning condition setting hand Cleaning condition setting unit 115 ... Pressure condition setting unit as pressurization condition setting unit 116 ... Ink remaining amount acquisition unit 117 ... Time measuring unit constituting condition acquisition unit LP ... Leak point Px ... Pressure force ( Target pressure), Tx ... pressurization holding time, B1 ... bubbles, B2 ... microbubbles as gaseous foreign matters.

Claims (6)

A cleaning to torque cleaning device fluid ejecting head that ejects fluid from Bruno nozzle,
A closing valve provided in the middle from the source of fluid flow-supplying passage supplying fluid to the fluid ejecting head,
First pressurizing means for pressurizing fluid from upstream of the blocking valve;
And suction means for sucking the fluid from the front Symbol nozzle,
The fluid that has been decompressed by the suction means being sucked by the suction means in a state where the shut-off valve is closed, and then the first pressurizing means is pressurized by opening the shut-off valve by flow, and control means for executing the cleaning for sucking and discharging the fluid from the front Symbol nozzle,
After the end of the cleaning, cleaning of the fluid ejecting apparatus characterized by comprising a second pressing means for increasing the fluid pressure of the fluid of the fluid supply channel under pressure through the nozzle device. The second pressure means, according to claim 1, characterized in that before Symbol fluid at least a portion of the region of the downstream portion communicating with the nozzle of the fluid supply passage pressurizes increasing the fluid pressure A cleaning device in the fluid ejection device according to claim 1. In the middle of the fluid supply flow path, a pressure reducing valve is provided that opens when the fluid is ejected from the nozzle of the fluid ejecting head and the valve chamber communicating with the nozzle is decompressed,
3. The fluid ejection according to claim 1, wherein the second pressurizing unit pressurizes the fluid in the fluid supply channel from both the upstream side and the downstream side with the pressure reducing valve interposed therebetween. Cleaning device in the device.   The cleaning in the fluid ejecting apparatus according to claim 1, wherein the first pressurizing unit and the second pressurizing unit perform pressurization using the same driving unit. apparatus. A fluid supply source, and a fluid ejecting head that ejects the supplied fluid from the nozzle through the fluid supply passage from the fluid supply source, further comprising a cleaning device according to any one of claims 1 to 4 A fluid ejecting apparatus. A fluid ejecting head that ejects fluid from Bruno nozzle a cleaning to torque cleaning method,
In a state where the fluid source was closed in the closed塞弁provided a fluid in the fluid supply passage on supplied to the fluid ejecting head, a downstream fluid from the closing valve by which aspirating fluid from the nozzle A depressurization step for depressurization;
Wherein the downstream fluid from the closure valve is opened the blocking valve in condition like that reduce the pressure, by flowing the pressurized fluid from the upstream from said closure valve, discharge for cleaning for sucking and discharging the fluid from the front Symbol nozzle Stages,
After the discharge step, the cleaning method in a fluid jet apparatus characterized by comprising a pressure step of increasing the fluid pressure of the fluid of the fluid supply channel under pressure through said nozzle.

Images