JP2019119180A - Liquid injection device - Google Patents

Abstract

To provide a liquid injection device which can inhibit leakage of a liquid.SOLUTION: A liquid jet device includes: a liquid jet head which jets a liquid supplied from a liquid storage part through a supply passage from nozzles; a cap which is configured to contact with the liquid jet head and can form a closed space in which the nozzles open; a suction part which can suction an interior of the cap through a suction passage; a detection part which can detect a pressure state of the suction passage; and an on-off valve which is provided in at least one of the supply passage and the suction passage and can open or close the passage. If the detection part detects an abnormal state in which the pressure of the suction passage gets out of a predetermined range, the on-off valve is closed.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a liquid ejecting apparatus such as an ink jet printer.

  Patent Document 1 describes a liquid ejecting apparatus including a liquid ejecting head that ejects liquid, a cap that caps the liquid ejecting head, and a suction unit connected to the cap via a flow path and that suctions the inside of the cap. ing. The liquid ejecting apparatus performs suction cleaning in which the liquid is ejected from the liquid ejecting head by driving the aspiration unit in a state where the liquid ejecting head is capped by the cap.

Unexamined-Japanese-Patent No. 2007-105599

  In the liquid ejecting apparatus described in Patent Document 1, when the suction unit is driven, an abnormality may occur in the pressure of the flow path due to excessive or insufficient negative pressure of the flow path, or the like. . In such a case, the liquid can not be normally sucked from the liquid jet head, which may lead to leakage of the liquid.

  An object of the present invention is to provide a liquid ejecting apparatus capable of suppressing liquid leakage.

Hereinafter, means for solving the above problems will be described.
A liquid ejecting apparatus that solves the above problems is configured to be able to contact a liquid ejecting head that ejects a liquid supplied from a liquid storage unit through a supply flow path from a nozzle, and the liquid ejecting head, and the nozzle opens. A cap that can form a closed space, a suction unit that can suction the inside of the cap via a suction channel, a detection unit that can detect the pressure state of the suction channel, the supply channel, and the suction channel An open / close valve provided on at least one of the plurality of flow paths and capable of opening and closing the flow path, and the detection valve detects an abnormal state in which the pressure in the suction flow path is out of a predetermined range; close up.

BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram which shows one Embodiment of a liquid injection apparatus. FIG. 2 is a block diagram showing an electrical configuration of a liquid ejecting apparatus. Flow chart of empty suction operation. Flow chart of negative pressure accumulation operation. Flow chart of negative pressure release operation. Flow chart of suction cleaning. Flow chart of startup operation. Flow chart of recovery operation. Flow chart of the specific operation. The flowchart which shows the modification of negative pressure release operation.

  Hereinafter, an embodiment of a liquid ejecting apparatus will be described with reference to the drawings. The liquid ejecting apparatus is, for example, an ink jet printer that records an image such as characters and photographs by ejecting ink, which is an example of liquid, onto a medium such as paper.

  As shown in FIG. 1, the liquid ejecting apparatus 11 includes a liquid ejecting head 12 that ejects a liquid, and a liquid storage unit 13 capable of accommodating the liquid supplied to the liquid ejecting head 12. The liquid ejecting apparatus 11 includes a pressurizing unit 14 capable of pressurizing the inside of the liquid ejecting head 12, a maintenance mechanism 15 for maintaining the liquid ejecting head 12, and a detecting unit 16 capable of detecting leakage of liquid.

  The liquid jet head 12 has one or more nozzles 17. The nozzle 17 is formed on the nozzle surface 18 of the liquid jet head 12. The liquid jet head 12 is configured to jet a liquid from the nozzle 17 toward the medium 99.

  The liquid storage unit 13 is connected to the liquid jet head 12 via the supply flow path 19. The liquid stored in the liquid storage portion 13 is supplied to the liquid jet head 12 through the supply flow path 19. The liquid jet head 12 jets the liquid supplied from the liquid storage unit 13 via the supply flow path 19 from the nozzle 17.

  The upstream end of the supply flow path 19 is connected to the liquid storage unit 13. The downstream end of the supply flow path 19 is connected to the liquid jet head 12. The liquid storage unit 13 is a container capable of storing a liquid. The liquid storage unit 13 may be, for example, a cartridge that can be attached to and detached from the liquid ejecting apparatus 11, or may be a tank that can replenish liquid.

  The pressurizing unit 14 is located in the middle of the supply flow path 19. The pressure unit 14 is located between the liquid storage unit 13 and the liquid jet head 12. The pressurizing unit 14 is configured of, for example, a diaphragm pump, a tube pump, or the like. The pressure unit 14 pressurizes the inside of the liquid jet head 12 through the supply flow path 19.

  The supply flow path 19 is provided with a pressure valve 21 which is an example of an on-off valve capable of opening and closing the supply flow path 19 which is a flow path. The pressure valve 21 is located between the pressure unit 14 and the liquid jet head 12. When the pressure valve 21 opens, the supply flow path 19 opens. When the pressure valve 21 is closed, the supply flow path 19 is closed. When the pressurizing unit 14 is driven in a state where the pressurizing valve 21 closes the supply flow path 19, a pressurizing force acting on the liquid jet head 12 is accumulated.

  In the supply flow path 19, a one-way valve 22 that allows the flow of liquid downstream and suppresses the flow of liquid upstream is provided between the pressurizing unit 14 and the liquid storage unit 13. The one-way valve 22 may be an on-off valve capable of opening and closing the supply flow path 19.

  The maintenance mechanism 15 includes a cap 31, a suction flow channel 32 whose upstream end is connected to the cap 31, and a suction section 33 which can suction the inside of the cap 31 via the suction flow channel 32. The maintenance mechanism 15 includes a suction valve 34, which is an example of an on-off valve capable of opening and closing the suction flow channel 32 which is a flow channel, and a negative pressure storage unit 35 communicating with the suction flow channel 32. The maintenance mechanism 15 includes a detection unit 36 capable of detecting the pressure state of the suction flow channel 32, and a waste liquid storage unit 37 to which the downstream end of the suction flow channel 32 is connected.

  The cap 31 is configured to be able to contact the liquid jet head 12. The cap 31 can form a closed space in which the nozzle 17 is opened by contacting the liquid jet head 12. Forming a closed space where the nozzle 17 is opened by contact between the cap 31 and the liquid jet head 12 is referred to as capping. The cap 31 caps the liquid jet head 12 by contacting the nozzle surface 18 of the liquid jet head 12.

  The cap 31 is provided with a drive mechanism 38. The drive mechanism 38 moves the cap 31 relative to the liquid jet head 12. The cap 31 contacts the liquid jet head 12 and is separated from the liquid jet head 12 by being moved by the drive mechanism 38. The cap 31 is moved by the drive mechanism 38 between a capping position for capping the liquid jet head 12 and a non-capping position for non-capping. When the cap 31 caps the liquid jet head 12, the liquid jet head 12 may approach the cap 31, or the cap 31 and the liquid jet head 12 may approach each other.

The suction unit 33 is located between the cap 31 and the waste liquid storage unit 37 in the suction flow channel 32. The suction unit 33 is configured by, for example, a diaphragm pump, a tube pump, or the like.
The suction valve 34 is provided in the suction flow channel 32 and is located between the cap 31 and the suction portion 33. When the suction valve 34 opens, the suction flow path 32 opens. When the suction valve 34 is closed, the suction channel 32 is closed.

  The negative pressure accumulation unit 35 is located between the suction valve 34 and the suction unit 33 in the suction flow channel 32. The negative pressure storage unit 35 is a container having a predetermined volume. The negative pressure storage unit 35 can store negative pressure generated by driving the suction unit 33. The negative pressure storage unit 35 is provided with a release valve 39 capable of opening the negative pressure storage unit 35 to the atmosphere. When the release valve 39 is opened, the negative pressure accumulation unit 35 is opened to the atmosphere. When the suction unit 33 is driven with the suction valve 34 and the release valve 39 closed, negative pressure is accumulated in the negative pressure accumulation unit 35.

  The detection unit 36 is located between the suction valve 34 and the suction unit 33 in the suction flow channel 32. The detection unit 36 of the present embodiment is attached to the negative pressure storage unit 35. The detection unit 36 detects the pressure state of the suction flow passage 32 via the negative pressure accumulation unit 35. The detection unit 36 is, for example, a pressure sensor capable of detecting a pressure. The liquid injection device 11 closes at least one of the pressure valve 21 and the suction valve 34, which are on-off valves, when the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 is out of the predetermined range. Configured

  The waste liquid storage unit 37 is a container capable of containing the liquid discharged from the liquid jet head 12. The waste liquid storage unit 37 stores the liquid received by the cap 31 via the suction flow channel 32 when the suction unit 33 is driven.

  The detection unit 16 can detect the leakage of the liquid in the liquid ejecting apparatus 11 by touching the leaking liquid. The detection unit 16 is preferably located below the suction flow channel 32. In this way, if the liquid leaks, it can be detected quickly.

  The liquid ejecting apparatus 11 can perform a maintenance operation for maintaining the liquid ejecting head 12. The maintenance operation of the liquid jet head 12 includes capping, flushing and cleaning. For example, when the power of the liquid ejecting apparatus 11 is turned off, or when the liquid ejecting apparatus 11 is in a resting state in which the liquid ejecting apparatus 11 does not execute the liquid ejecting operation, the liquid in the nozzle 17 is capped when the cap 31 caps the liquid ejecting head 12 Drying is suppressed.

  The flushing is an operation in which the liquid jet head 12 discharges the liquid unrelated to the printing from the nozzle 17. The liquid discharged by flushing may be received by the cap 31 or may be received by another member. When flushing is performed, clogging of the nozzle 17 due to thickening or solidification of the liquid in the nozzle 17 is suppressed.

  The cleaning is an operation of discharging the liquid from the nozzle 17 to discharge foreign substances such as bubbles contained in the liquid. The liquid discharged by the cleaning may be received by the cap 31 or other members. Types of cleaning include pressure cleaning, suction cleaning and chalk cleaning. Chalk cleaning is a type of suction cleaning. In the pressure cleaning, the liquid is discharged from the nozzle 17 by the pressure generated by the drive of the pressure unit 14.

  The suction cleaning is an operation of discharging the liquid from the nozzle 17 by the negative pressure generated by the drive of the suction unit 33. The liquid discharged by suction cleaning is received by the cap 31. In the suction cleaning, the negative pressure generated by the drive of the suction portion 33 is applied to the closed space formed when the cap 31 caps the liquid jet head 12, whereby the liquid is sucked from the nozzle 17.

  Chalk cleaning is performed by performing suction cleaning with the pressure valve 21 closed and then opening the pressure valve 21. When the pressure inside the liquid jet head 12 becomes negative while the supply flow path 19 is closed, bubbles contained in the liquid expand. Therefore, when the supply flow path 19 is opened after the suction unit 33 sucks the inside of the cap 31 for capping the liquid jet head 12, the bubbles contained in the liquid can be efficiently discharged.

  After the cleaning is performed, an empty suction operation may be performed to discharge the liquid discharged to the cap 31 from the inside of the cap 31. The empty suction operation is an operation in which the suction unit 33 is driven to suction the liquid in the cap 31. When the suction unit 33 is driven while the inside of the cap 31 is open to the atmosphere, the liquid in the cap 31 is drawn. The liquid sucked from inside the cap 31 is stored in the waste liquid storage unit 37.

  When cleaning is performed, the discharged liquid may contaminate the nozzle surface 18. Therefore, the liquid ejecting apparatus 11 may include a wiping unit that wipes the nozzle surface 18. The wiping unit is composed of, for example, a rubber wiper and a cloth wiper.

  As shown in FIG. 2, the liquid ejecting apparatus 11 includes a control unit 41 that integrally controls the entire apparatus, and a storage unit 42 that stores various types of information. The control unit 41 controls the operation of the liquid ejecting apparatus 11 based on the information stored in the storage unit 42. The control unit 41 is connected to the liquid jet head 12, the drive mechanism 38, the pressure unit 14, the pressure valve 21, the suction unit 33, and the suction valve 34 so as to be able to transmit signals. The control unit 41 is connected to be able to receive the signals from the detection unit 16 and the detection unit 36. The control unit 41 may be configured to be able to communicate with each other.

  The control unit 41 determines whether the pressure state of the suction flow passage 32 is normal or abnormal based on the pressure of the suction flow passage 32 detected by the detection unit 36. The control unit 41 determines that the pressure state of the suction flow path 32 is normal when the pressure of the suction flow path 32 falls within a predetermined range. The control unit 41 determines that the pressure state of the suction flow path 32 is an abnormal state when the pressure of the suction flow path 32 is out of the predetermined range. Thus, the detection unit 36 can detect the pressure state of the suction flow path 32. The control unit 41 controls the operation of the liquid ejecting apparatus 11 based on the pressure state of the suction flow path 32 detected by the detection unit 36.

  When performing the cleaning, the control unit 41 appropriately executes an empty suction operation, a negative pressure accumulation operation, a negative pressure release operation, and the like. The negative pressure accumulation operation is an operation in which the suction unit 33 is driven to accumulate negative pressure in the negative pressure accumulation unit 35. That is, the negative pressure accumulation operation is an operation in which the suction unit 33 sucks the inside of the negative pressure storage unit 35. When the negative pressure is accumulated in the negative pressure accumulation unit 35 by the negative pressure accumulation operation, the pressure of the negative pressure accumulation unit 35 is reduced.

  The negative pressure release operation is an operation of releasing the negative pressure accumulated in the negative pressure accumulation unit 35. Therefore, the negative pressure release operation is performed after the negative pressure accumulation operation is performed. When the negative pressure stored in the negative pressure storage unit 35 is released by the negative pressure release operation, the pressure of the negative pressure storage unit 35 is increased.

  The storage unit 42 is configured by, for example, a RAM, and configured to store detection when an abnormal state of the suction flow channel 32 is detected by the detection unit 36. That is, the storage unit 42 can store that the detection unit 36 has detected an abnormal state of the suction flow channel 32. The storage unit 42 can store the start of the empty suction operation, the negative pressure accumulation operation, and the negative pressure release operation at the start of the operation. The storage unit 42 is capable of resetting the storage of the operation start at the end of the idle suction operation, the negative pressure accumulation operation, and the negative pressure release operation.

Next, an operation performed by the liquid ejecting apparatus 11 will be described.
First, the empty suction operation will be described.
As shown in FIG. 3, when performing the idle suction operation, first, in step S101, the control unit 41 sets an operating flag. That is, the control unit 41 stores the operation start in the storage unit 42 at the start of the idle suction operation.

The control unit 41 moves the cap 31 to the uncapping position in step S102.
The control unit 41 opens the suction valve 34 in step S103.

The controller 41 closes the release valve 39 in step S104.
The control unit 41 drives the suction unit 33 in step S105. At this time, since the suction flow channel 32 is open, the suction unit 33 sucks the inside of the cap 31 via the suction flow channel 32.

  In step S106, the control unit 41 determines whether the pressure in the suction flow channel 32 is equal to or higher than a first threshold. At this time, the control unit 41 compares the pressure of the suction flow path 32 detected by the detection unit 36 with the first threshold stored in the storage unit 42. When the pressure of the suction flow path 32 is equal to or higher than the first threshold in step S106, the control unit 41 shifts the process to step S107. When the pressure of the suction flow path 32 falls below the first threshold in step S106, the control unit 41 shifts the process to step S121.

The control unit 41 stops the suction unit 33 in step S107.
The controller 41 opens the release valve 39 in step S108. Thus, the negative pressure remaining in the negative pressure storage unit 35 is released.

In step S109, the control unit 41 moves the cap 31 to the capping position. Thereby, the drying of the liquid in the nozzle 17 is suppressed.
In step S110, the control unit 41 resets the in-operation flag set in step S101. That is, the control unit 41 erases the storage of the operation start stored in the storage unit 42. After finishing the process of step S110, the control unit 41 ends the empty suction operation.

  When the pressure of the suction flow path 32 falls below the first threshold in step S106, the control unit 41 determines whether or not a predetermined time has elapsed in step S121. At this time, the control unit 41 compares the time elapsed after the suction unit 33 starts driving with the predetermined time stored in the storage unit 42. In step S121, when a predetermined time has elapsed since the suction unit 33 starts driving, the control unit 41 shifts the process to step S122. In step S121, if the predetermined time has not elapsed since the suction unit 33 started driving, the control unit 41 returns the process to step S106.

  In steps S106 and S121, the control unit 41 determines whether or not the pressure in the suction flow passage 32 becomes equal to or higher than the first threshold while a predetermined time has elapsed since the suction unit 33 started driving. . When the pressure in the suction flow channel 32 becomes equal to or higher than the first threshold in steps S106 and S121, the control unit 41 waits for a predetermined period of time, assuming that the pressure state in the suction flow channel 32 is normal. Then, the process proceeds to step S107. That is, in step S106 and step S121, the control unit 41 shifts the process to step S107 when the pressure of the suction flow channel 32 is within the predetermined range.

  The control unit 41 determines that the pressure state of the suction flow path 32 is abnormal if the pressure of the suction flow path 32 falls below the first threshold even after a predetermined time has elapsed in steps S106 and S121. The process proceeds to S122. That is, the control unit 41 shifts the process to step S122 when the pressure of the suction passage 32 is out of the predetermined range in step S106 and step S121.

  Normally, when the suction unit 33 continues to be driven for a predetermined time, the liquid in the cap 31 is sufficiently sucked. Therefore, the predetermined time in step S121 is a time when it is expected that the liquid in the cap 31 can be sufficiently sucked by driving the suction unit 33. The liquid sucked from the inside of the cap 31 by the suction unit 33 is stored in the waste liquid storage unit 37.

  Immediately after the suction unit 33 starts driving, the liquid in the cap 31 is suctioned, so the pressure of the suction flow channel 32 falls below the first threshold. When the suction unit 33 continues to be driven as it is, the air is sucked from the inside of the cap 31 so that the pressure of the suction flow channel 32 becomes equal to or higher than the first threshold. That is, when the pressure in the suction flow channel 32 becomes equal to or higher than the first threshold value, it can be determined that the liquid in the cap 31 is sufficiently sucked. For this reason, when the pressure of the suction flow path 32 is lower than the first threshold value for a predetermined time, it is determined that the pressure state of the suction flow path 32 is abnormal.

  As a factor that causes the pressure of the suction flow path 32 to fall below the first threshold during the idle suction operation, there is a malfunction of the cap 31 and the suction valve 34. For example, although the control unit 41 controls the cap 31 to move to the non-capping position in step S102, if the cap 31 is positioned at the capping position, the pressure state of the suction flow path 32 is abnormal. Become. For example, although the control unit 41 controls the suction valve 34 to open in step S103, if the suction valve 34 is closed, the pressure state of the suction flow channel 32 becomes abnormal.

  When the cap 31 is positioned at the capping position due to the malfunction of the cap 31, when the suction unit 33 is driven in step S105, the pressure in the suction flow path 32 decreases because the inside of the cap 31 is not open to the atmosphere. That is, the negative pressure of the suction flow path 32 becomes excessive. Thereby, the pressure of the suction flow path 32 falls below the first threshold. At this time, the liquid flows out of the nozzle 17 by the drive of the suction unit 33. If the suction unit 33 continues to be driven as it is, the liquid may continue to flow from the nozzle 17 and the liquid may leak from the cap 31. In particular, when the inside of the cap 31 is filled with the liquid because the liquid continues to flow from the nozzle 17, the liquid in the cap 31 and the liquid in the nozzle 17 may be connected. If this happens, the liquid may continue to flow from the liquid storage unit 13 due to the water head difference. Therefore, the control unit 41 closes the suction valve 34 in step S122. The control unit 41 prevents the liquid from flowing out from the nozzle 17 by closing the suction valve 34 when the pressure state of the suction flow channel 32 becomes abnormal during the idle suction operation. As a result, liquid leakage is suppressed.

  When the suction valve 34 is closed due to the malfunction of the suction valve 34, when the suction unit 33 is driven in step S105, the pressure in the suction flow channel 32 is reduced. That is, the negative pressure of the suction flow path 32 becomes excessive. Thereby, the pressure of the suction flow path 32 falls below the first threshold. At this time, since the suction valve 34 is closed, the negative pressure by the suction unit 33 does not reach the cap 31. Therefore, even if the cap 31 is located at the capping position, there is no possibility that the liquid is sucked from the nozzle 17. That is, when the suction valve 34 is closed due to the malfunction of the suction valve 34, it does not lead to the liquid leakage.

  The control unit 41 stops the suction unit 33 in step S123. As a result, the possibility that liquid is sucked from the nozzle 17 by the suction unit 33 is reduced. Steps S122 and S123 may be switched in order or may be executed in parallel. The liquid injection device 11 is a suction valve which is an open / close valve when the detection unit 36 detects an abnormal state in which the pressure in the suction flow path 32 falls below a first threshold for a predetermined time when executing the idle suction operation. 34 is closed and the suction unit 33 is stopped.

  The control unit 41 sets an error flag in step S124. That is, the control unit 41 causes the storage unit 42 to store that the detection unit 36 has detected an abnormal state. After completing the process of step S124, the control unit 41 ends the empty suction operation as an empty suction error. If an empty suction error occurs, the liquid ejection device 11 will not accept any operation unless the power is turned on again.

Next, the negative pressure accumulation operation will be described.
As shown in FIG. 4, when executing the negative pressure accumulation operation, first, in step S201, the control unit 41 sets an in-operation flag. That is, at the start of the negative pressure accumulation operation, the control unit 41 stores the operation start in the storage unit 42.

The control unit 41 closes the suction valve 34 in step S202.
The controller 41 closes the release valve 39 in step S203. At this time, since the suction valve 34 is closed, the negative pressure storage unit 35 is a closed space.

  The control unit 41 drives the suction unit 33 in step S204. At this time, the suction unit 33 sucks the inside of the negative pressure storage unit 35. As a result, negative pressure is accumulated in the negative pressure accumulation unit 35. As a result, the pressure of the negative pressure storage unit 35 is reduced.

  In step S205, the control unit 41 determines whether the pressure in the suction flow path 32 falls below the second threshold. At this time, the control unit 41 compares the pressure of the suction flow path 32 detected by the detection unit 36 with the second threshold stored in the storage unit 42. When the pressure of the suction flow path 32 falls below the second threshold in step S205, the control unit 41 shifts the process to step S206. When the pressure of the suction flow path 32 becomes equal to or higher than the second threshold in step S205, the control unit 41 shifts the processing to step S211.

The control unit 41 stops the suction unit 33 in step S206. Thereby, the accumulation of the negative pressure in the negative pressure accumulation part 35 is completed.
In step S207, the control unit 41 resets the in-operation flag set in step S201. That is, the control unit 41 erases the storage of the operation start stored in the storage unit 42. After completing the process of step S207, the control unit 41 ends the negative pressure accumulation operation.

  When the pressure of the suction flow path 32 becomes equal to or higher than the second threshold in step S205, the control unit 41 determines whether or not a predetermined time has elapsed in step S211. At this time, the control unit 41 compares the time elapsed after the suction unit 33 starts driving with the predetermined time stored in the storage unit 42. In step S211, when a predetermined time has elapsed since the suction unit 33 started driving, the control unit 41 shifts the process to step S212. In step S211, if the predetermined time has not elapsed since the suction unit 33 started driving, the control unit 41 returns the process to step S205.

  In steps S205 and S211, the control unit 41 determines whether or not the pressure in the suction flow passage 32 falls below the second threshold while the suction unit 33 continues to be driven for a predetermined time. The control unit 41 determines that the pressure state of the suction flow channel 32 is normal when the pressure of the suction flow channel 32 is lower than the second threshold in steps S205 and S211, and does not wait for a predetermined time to elapse. The process proceeds to step S206. That is, in step S205 and step S211, the control unit 41 shifts the process to step S206 when the pressure of the suction flow channel 32 is within the predetermined range.

  Even when the suction unit 33 continues driving for a predetermined time, the control unit 41 determines that the pressure in the suction passage 32 is equal to or higher than the second threshold, that is, negative pressure is not accumulated even after the predetermined time has elapsed. On the assumption that the pressure state of the suction flow path 32 is abnormal, the process proceeds to step S212. That is, in step S205 and step S211, when the pressure of the suction flow channel 32 is out of the predetermined range, the control unit 41 shifts the process to step S212.

  Normally, when the suction unit 33 continues to be driven for a predetermined time, a negative pressure is sufficiently accumulated in the negative pressure accumulation unit 35. Therefore, the predetermined time in step S211 is a time when it is expected that negative pressure is sufficiently accumulated in the negative pressure accumulation unit 35 by driving of the suction unit 33.

  The factors causing the pressure in the suction flow path 32 to be equal to or higher than the second threshold during the negative pressure accumulation operation include breakage of the negative pressure accumulation unit 35 and malfunction in the release valve 39 and the suction valve 34. For example, if the negative pressure storage portion 35 is broken such as a crack or a hole, the pressure state of the suction flow path 32 becomes an abnormal state. For example, although the control unit 41 controls the release valve 39 to close in step S203, if the release valve 39 is open, the pressure state of the suction flow path 32 becomes abnormal. For example, although the control unit 41 controls the suction valve 34 to close in step S202, if the suction valve 34 is open, the pressure state of the suction flow channel 32 becomes abnormal. That is, when the negative pressure storage unit 35 is open to the atmosphere, the negative pressure of the suction flow channel 32 communicating with the negative pressure storage unit 35 is insufficient, and the pressure state of the suction flow channel 32 becomes abnormal.

  If the negative pressure storage unit 35 is damaged, even if the suction unit 33 is driven in step S204, the pressure of the negative pressure storage unit 35 does not decrease because the negative pressure storage unit 35 is open to the atmosphere. Thereby, the pressure of the suction flow channel 32 becomes equal to or higher than the second threshold. When the release valve 39 is opened due to the malfunction of the release valve 39, the same applies to the case where the suction valve 34 is opened due to the malfunction of the suction valve 34.

  When the suction valve 34 is open due to the malfunction of the suction valve 34, the liquid flows out of the nozzle 17 by the drive of the suction portion 33 when the cap 31 is at the capping position. If the suction unit 33 continues to be driven as it is, the liquid may continue to flow from the nozzle 17 and the liquid may leak from the cap 31. Therefore, the negative pressure accumulation operation is preferably performed in a state where the cap 31 is at the non-capping position.

  The control unit 41 closes the suction valve 34 in step S212. The reason is that the suction valve 34 may be open when the pressure in the suction passage 32 is equal to or higher than the second threshold. Even when the suction valve 34 does not operate properly in step S202, the suction valve 34 may close as the control unit 41 controls the suction valve 34 again to close. Therefore, the control unit 41 closes the suction valve 34 in step S212.

  The control unit 41 prevents the liquid from flowing out of the nozzle 17 by closing the suction valve 34 when the pressure state of the suction flow channel 32 becomes abnormal during the negative pressure accumulation operation. As a result, liquid leakage is suppressed. In the negative pressure accumulation operation, when the pressure in the suction flow path 32 falls below the second threshold, the suction valve 34 is closed, so the operation of closing the suction valve 34 is unnecessary.

  If the negative pressure accumulation unit 35 is broken, the negative pressure by the suction unit 33 does not reach the cap 31 if the suction valve 34 is operating properly. Therefore, even if the cap 31 is located at the capping position, there is no possibility that liquid will flow out of the nozzle 17 if the suction valve 34 is closed. That is, even if the negative pressure storage unit 35 is broken, the liquid will not leak if the suction valve 34 operates properly. The same applies to the case where the release valve 39 is open due to the malfunction of the release valve 39.

  The control unit 41 stops the suction unit 33 in step S213. As a result, the possibility of the liquid flowing out of the nozzle 17 due to the negative pressure of the suction portion 33 is reduced. Steps S212 and S213 may be switched in order or may be executed in parallel. In the liquid ejecting apparatus 11, when performing the negative pressure accumulation operation, the detecting unit 36 detects an abnormal state in which the pressure of the suction flow passage 32 becomes equal to or higher than the second threshold even if the suction unit 33 continues to be driven for a predetermined time. When it detects, the suction valve 34 which is an on-off valve is closed and the suction part 33 is stopped.

  In step S214, the control unit 41 sets an error flag. That is, the control unit 41 causes the storage unit 42 to store that the detection unit 36 has detected an abnormal state. After completing the process of step S214, the control unit 41 ends the negative pressure accumulation operation as a negative pressure accumulation error. When a negative pressure accumulation error occurs, the liquid ejecting apparatus 11 does not receive an operation unless the power is turned on again.

Next, the negative pressure releasing operation will be described. The negative pressure release operation is performed after the negative pressure accumulation operation is performed.
As shown in FIG. 5, when executing the negative pressure releasing operation, first, the control unit 41 sets an operating flag in step S301. That is, at the start of the negative pressure releasing operation, the control unit 41 stores the start of the operation in the storage unit 42.

  The control unit 41 opens the suction valve 34 in step S302. At this time, since the negative pressure is accumulated in the negative pressure accumulation unit 35 by the negative pressure accumulation operation, the negative pressure is applied to the inside of the cap 31 by opening the suction valve 34. When the cap 31 is located at the capping position, the negative pressure accumulated in the negative pressure accumulation unit 35 is applied to the inside of the cap 31, whereby the liquid is sucked from the nozzle 17. When the cap 31 is located at the non-capping position, the negative pressure accumulated in the negative pressure accumulation unit 35 is applied to the inside of the cap 31, whereby the liquid or the atmosphere in the cap 31 is sucked. Thereby, the negative pressure of the negative pressure storage part 35 is cancelled.

  In step S303, the control unit 41 determines whether the pressure in the suction flow channel 32 is equal to or higher than a third threshold. At this time, the control unit 41 compares the pressure of the suction flow path 32 detected by the detection unit 36 with the third threshold stored in the storage unit 42. When the pressure of the suction flow path 32 becomes equal to or higher than the third threshold in step S303, the control unit 41 shifts the process to step S304. When the pressure of the suction flow path 32 falls below the third threshold in step S303, the control unit 41 shifts the process to step S311.

The controller 41 closes the suction valve 34 in step S304.
The controller 41 opens the release valve 39 in step S305.
In step S306, the control unit 41 waits for a predetermined time. The negative pressure accumulated in the negative pressure accumulation unit 35 is released as time passes after the release valve 39 is opened. Therefore, the predetermined time in step S306 is a time that is expected to be required for the negative pressure of the negative pressure storage unit 35 to be sufficiently released.

  In step S307, the control unit 41 resets the in-operation flag set in step S301. That is, the control unit 41 erases the storage of the start of the operation stored in the storage unit 42. After completing the process of step S307, the control unit 41 ends the negative pressure release operation.

  When the pressure of the suction flow path 32 falls below the third threshold in step S303, the control unit 41 determines whether or not a predetermined time has elapsed in step S311. At this time, the control unit 41 compares the time elapsed from the control of opening the suction valve 34 with the predetermined time stored in the storage unit 42. If it is determined in step S311 that the suction valve 34 has been opened and the predetermined time has elapsed in step S311, the control unit 41 shifts the process to step S312. If it is determined in step S311 that the suction valve 34 has been opened and the predetermined time has not elapsed in step S311, the control unit 41 returns the process to step S303.

  The control unit 41 determines whether the pressure in the suction flow passage 32 becomes equal to or higher than the third threshold while the predetermined time elapses after the suction valve 34 is controlled to open in steps S303 and S311. Do. When the pressure in the suction flow channel 32 becomes equal to or higher than the third threshold in steps S303 and S311, the control unit 41 waits for a predetermined time to elapse, assuming that the pressure state in the suction flow channel 32 is normal. Then, the process proceeds to step S304. That is, when the pressure of the suction flow channel 32 is in the predetermined range, the control unit 41 shifts the process to step S304.

  In steps S303 and S311, the controller 41 performs suction when the pressure in the suction channel 32 falls below the third threshold even after a predetermined time has elapsed, that is, when the negative pressure in the suction channel 32 is not released. Assuming that the pressure state of the flow path 32 is abnormal, the process proceeds to step S312. That is, in step S303 and step S311, when the pressure of the suction flow channel 32 is out of the predetermined range, the control unit 41 shifts the processing to step S312.

  The negative pressure accumulated in the negative pressure accumulation unit 35 is released as time passes after the suction valve 34 is opened. Therefore, the predetermined time in step S311 is a time that is expected to be required for the negative pressure of the negative pressure storage unit 35 to be sufficiently released.

  The factors causing the pressure in the suction flow path 32 to fall below the third threshold during the negative pressure release operation include clogging of the suction flow path 32 and malfunction of the suction valve 34. For example, when the liquid solidifies in the suction flow channel 32, the suction flow channel 32 is closed, and the pressure state of the suction flow channel 32 becomes abnormal. For example, although the control unit 41 controls the suction valve 34 to open in step S302, if the suction valve 34 is closed, the pressure state of the suction flow path 32 becomes abnormal. That is, if the negative pressure storage unit 35 is not open to the atmosphere, the negative pressure of the suction flow channel 32 leading to the negative pressure storage unit 35 is not released because the negative pressure is not released, and the pressure state of the suction flow channel 32 becomes abnormal.

  If the suction flow path 32 is clogged, even if the suction valve 34 is opened in step S302, the negative pressure storage unit 35 is a closed space, so the negative pressure of the negative pressure storage unit 35 is not released. As a result, the pressure of the suction flow passage 32 communicating with the negative pressure storage unit 35 falls below the third threshold. Even when the suction valve 34 is closed due to the malfunction of the suction valve 34, the negative pressure storage unit 35 is a closed space, so the pressure of the suction passage 32 communicating with the negative pressure storage unit 35 falls below the third threshold.

  When the suction flow path 32 is clogged, the clog may be eliminated unexpectedly by the negative pressure accumulated in the negative pressure accumulation unit 35. In this case, when the cap 31 is at the capping position, the negative pressure of the negative pressure storage unit 35 causes the liquid to flow out of the nozzle 17. If left as it is, the liquid may continue to flow from the nozzle 17 and the liquid may leak from the cap 31.

  The control unit 41 closes the suction valve 34 in step S312. The control unit 41 closes the suction valve 34 when the pressure state of the suction flow passage 32 becomes abnormal during the negative pressure accumulation operation, so that the negative pressure accumulated in the negative pressure accumulation unit 35 is accidentally cap 31 Suppress the reach of the inside. As a result, liquid leakage is suppressed. When performing a negative pressure release operation, the liquid injection device 11 controls the suction valve 34 which is an on-off valve to open, and then the pressure of the suction flow path 32 falls below the third threshold even if a predetermined time has elapsed. When the detection unit 36 detects an abnormal state, the suction valve 34 is closed.

  When the suction valve 34 is closed due to the malfunction of the suction valve 34, the negative pressure accumulated in the negative pressure accumulation unit 35 does not reach the cap 31. Therefore, even if the cap 31 is located at the capping position, there is no possibility that the liquid is sucked from the nozzle 17. That is, when the suction valve 34 is closed due to the malfunction of the suction valve 34, it does not lead to the liquid leakage.

  In step S313, the control unit 41 sets an error flag. That is, the control unit 41 causes the storage unit 42 to store that the detection unit 36 has detected an abnormal state. After completing the process of step S313, the control unit 41 ends the negative pressure release operation as a negative pressure release error. When a negative pressure release error occurs, the liquid ejecting apparatus 11 does not receive an operation unless the power is turned on again.

Next, the suction cleaning operation will be described.
As shown in FIG. 6, when performing suction cleaning, the control unit 41 first moves the cap 31 to the non-capping position in step S401.

  In step S402, the control unit 41 executes a negative pressure accumulation operation. As a result, negative pressure is accumulated in the negative pressure accumulation unit 35. By executing the negative pressure accumulation operation with the cap 31 positioned at the non-capping position, the possibility of the liquid flowing out of the nozzle 17 at the time of a negative pressure accumulation error is reduced.

The controller 41 moves the cap 31 to the capping position in step S403.
In step S404, the control unit 41 executes a negative pressure releasing operation. As a result, the liquid is sucked from the nozzle 17 by the negative pressure accumulated in the negative pressure accumulation unit 35.

  In step S405, the control unit 41 executes an empty suction operation. As a result, the liquid discharged into the cap 31 by the negative pressure releasing operation in step S404 is sucked and stored in the waste liquid storage unit 37. After finishing the process of step S405, the control unit 41 ends the suction cleaning.

  Next, the start-up operation when the liquid ejecting apparatus 11 is powered on will be described. The start-up operation is performed, for example, when the liquid ejecting apparatus 11 does not receive an operation due to an empty suction error, a negative pressure accumulation error, or a negative pressure release error, and the apparatus main body is powered on again.

  As shown in FIG. 7, when executing the start-up operation, the control unit 41 first determines in step S501 whether or not there is liquid leakage in the liquid ejecting apparatus 11. At this time, the control unit 41 determines whether the detection unit 16 detects a liquid. In step S501, when the detection unit 16 detects a liquid, the control unit 41 ends the startup operation as a leakage error. When a leakage error occurs, the liquid ejecting apparatus 11 does not receive an operation unless the power is turned on again. In step S501, when the detection unit 16 does not detect the liquid, the control unit 41 shifts the process to step S502.

  In step S502, the control unit 41 confirms whether an error flag is set. That is, the control unit 41 determines whether the storage unit 42 stores that the detection unit 36 has detected an abnormal state. For example, when an error occurs in the idle suction operation, the negative pressure accumulation operation, and the negative pressure release operation, when the power is turned on again in that state, the start-up operation is performed with the error flag set. When the error flag is set in step S502, the control unit 41 shifts the process to step S511. When the error flag is not set in step S502, the control unit 41 shifts the process to step S503.

  In step S503, the control unit 41 confirms whether the in-operation flag is set. That is, the control unit 41 determines whether the storage unit 42 stores the start of the empty suction operation, the negative pressure accumulation operation, and the negative pressure release operation. For example, if a power failure occurs during the empty suction operation, negative pressure accumulation operation, or negative pressure release operation or the power is turned off, if the power is turned on in that state, the start-up flag is set while starting up The action is performed. When the in-operation flag is set in step S503, the control unit 41 shifts the processing to step S511. In step S503, when the in-operation flag is not set, the control unit 41 ends the startup operation.

  When the error flag is set in step S502 or when the in-operation flag is set in step S503, the control unit 41 executes the recovery operation in step S511. The recovery operation is an operation for recovering the liquid ejecting apparatus 11.

At step S512, the control unit 41 resets the error flag.
In step S513, the control unit 41 resets the in-operation flag. After completing the process of step S513, the control unit 41 ends the startup operation.

Next, the recovery operation will be described.
As shown in FIG. 8, when executing the recovery operation, first, the control unit 41 executes a specific operation in step S601. The specific operation is an operation for identifying a factor causing the pressure state of the suction flow path 32 to be an abnormal state. The specific operation includes a negative pressure accumulation operation and a negative pressure release operation. That is, when the storage unit 42 stores that the detection unit 36 detects an abnormal state when the power supply of the apparatus main body is turned on, the liquid ejecting apparatus 11 executes the negative pressure accumulation operation and the negative pressure release operation. Do. Thereby, the factor by which the pressure state of the suction flow path 32 will be abnormal state is specified.

  In step S602, the control unit 41 executes an empty suction operation. That is, the liquid ejecting apparatus 11 executes the idle suction operation when the storage unit 42 stores the start of the idle suction operation, the negative pressure accumulation operation, and the negative pressure release operation when the power of the device main body is turned on. .

  When the recovery operation is performed in the startup operation, an error flag or an in-operation flag is stored in the storage unit 42. If the error flag is stored, there is a possibility that liquid remains in the cap 31 because the empty suction error, the negative pressure accumulation error, or the negative pressure release error is set to suppress leakage of the liquid. . If the in-operation flag is stored, liquid may remain in the cap 31 because power may be cut off or the power may be cut off during suction cleaning. Therefore, the control unit 41 sucks the liquid in the cap 31 by executing the empty suction operation. Thereby, the leakage of the liquid is suppressed.

  The control unit 41 executes suction cleaning in step S603. That is, in step S603, the control unit 41 executes the negative pressure accumulation operation, the negative pressure release operation, and the idle suction operation in this order. After completing the process of step S603, the control unit 41 ends the recovery operation.

Next, the specific operation will be described.
As shown in FIG. 9, when executing the specific operation, first, the control unit 41 executes a negative pressure accumulation operation in step S701. As a result, negative pressure is accumulated in the negative pressure accumulation unit 35. At this time, if a negative pressure accumulation error occurs, the malfunction of the suction valve 34, the malfunction of the release valve 39, or the breakage of the negative pressure accumulator 35 can be considered. That is, when a negative pressure accumulation error occurs in step S701, the factors causing the pressure state of the suction flow path 32 to be abnormal include malfunction of the suction valve 34, malfunction of the release valve 39, and breakage of the negative pressure storage unit 35. Can be identified as at least one of

  If a negative pressure accumulation error occurs in step S701, it may be confirmed by the detection unit 16 whether or not there is liquid leakage. When the negative pressure storage unit 35 is broken, there is a high possibility that the liquid may leak from the negative pressure storage unit 35. Therefore, when the detection unit 16 detects a liquid, it can be identified that the negative pressure storage unit 35 is broken. If a negative pressure accumulation error occurs in step S701, the control unit 41 ends the specific operation.

  If no negative pressure accumulation error occurs in step S701, it is known that at least the negative pressure accumulation unit 35 is not damaged. The reason is that the suction valve 34 and the release valve 39 may be in a closed state to cause malfunction.

  The controller 41 opens the release valve 39 in step S702. Thus, the negative pressure storage unit 35 is opened to the atmosphere. At this time, the negative pressure accumulated in the negative pressure accumulation unit 35 in step S701 is released via the release valve 39. That is, the liquid injection device 11 performs a negative pressure releasing operation by opening the release valve 39 in order to release the negative pressure of the negative pressure storage unit 35.

  In step S703, the control unit 41 determines whether the pressure of the suction flow path 32 detected by the detection unit 36 is equal to or higher than a third threshold. At this time, the control unit 41 compares the pressure of the suction flow path 32 detected by the detection unit 36 with the third threshold stored in the storage unit 42. When the pressure of the suction flow path 32 becomes equal to or higher than the third threshold in step S703, the control unit 41 shifts the process to step S704. In step S703, when the pressure of the suction flow path 32 falls below the third threshold in step S703, the control unit 41 shifts the processing to step S711.

  In step S711, the control unit 41 determines whether a predetermined time has elapsed. At this time, the control unit 41 compares the time elapsed after the release valve 39 is controlled to open and the predetermined time stored in the storage unit 42. If it is determined in step S711 that the release valve 39 has been opened and the predetermined time has elapsed, the control unit 41 shifts the processing to step S712. If it is determined in step S711 that the release valve 39 has been opened and the predetermined time has not elapsed, the control unit 41 returns the process to step S703.

  In step S703 and step S711, the control unit 41 determines whether or not the pressure in the suction flow passage 32 becomes equal to or higher than the third threshold while the release valve 39 is controlled to be opened and then a predetermined time elapses. Do. If the pressure in the suction flow channel 32 is equal to or higher than the third threshold value, it is determined that the pressure state in the suction flow channel 32 is normal, and the process proceeds to step S704 without waiting for a predetermined time to elapse. If the pressure in the suction flow path 32 falls below the third threshold even after the predetermined time has elapsed, that is, if the negative pressure in the suction flow path 32 is not released, the pressure state in the suction flow path 32 is abnormal. The process proceeds to step S712.

  The negative pressure accumulated in the negative pressure accumulation unit 35 is released as time passes after the release valve 39 is opened. Therefore, the predetermined time in step S711 is a time that is expected to be required for the negative pressure of the negative pressure storage unit 35 to be sufficiently released.

  An operation failure of the release valve 39 is a factor that causes the pressure of the suction flow passage 32 to fall below the third threshold even after a predetermined time has elapsed since the release valve 39 was controlled to be opened. Even though the control unit 41 controls the release valve 39 to open in step S702, if the release valve 39 is closed, the negative pressure of the suction flow path 32 remains excessive and such an abnormal state occurs.

  In step S712, the control unit 41 sets an error flag. That is, the control unit 41 causes the storage unit 42 to store that the detection unit 36 has detected an abnormal state. After completing the process of step S712, the control unit 41 ends the specific operation, the recovery operation, and the start-up operation as a negative pressure release error. As described above, when the negative pressure release error is output after the process of step S 712, it is possible to specify that the cause of the abnormal pressure state of the suction passage 32 is the malfunction of the release valve 39. If the pressure in the suction flow path 32 is equal to or higher than the third threshold value in step S703, it is known that the release valve 39 has not malfunctioned. When a negative pressure release error occurs due to the malfunction of the release valve 39, the liquid ejecting apparatus 11 does not accept the operation unless the power is turned on again.

  When the pressure of the suction flow path 32 is equal to or higher than the third threshold in step S703, the control unit 41 performs a negative pressure accumulation operation in step S704. As a result, negative pressure is accumulated in the negative pressure accumulation unit 35.

  The control unit 41 moves the cap 31 to the non-capping position in step S705. As a result, the inside of the cap 31 is open to the atmosphere. The order of steps S704 and S705 may be reversed.

  In step S706, the control unit 41 executes a negative pressure releasing operation. That is, by opening the suction valve 34, the negative pressure of the negative pressure storage unit 35 is released. At this time, when a negative pressure release error occurs, it can be identified that at least one of the cap 31 and the suction valve 34 has malfunctioned.

  In step S 707, the control unit 41 moves the cap 31 to the capping position. Thereby, the drying of the liquid in the nozzle 17 is suppressed. When the control unit 41 completes the process of step S707, the control unit 41 ends the specific operation.

Next, the operation and effects of the liquid ejecting apparatus 11 configured as described above will be described.
(1) When the on-off valve (pressure valve 21) provided in the supply flow path 19 is closed, the supply of the liquid flowing from the liquid storage unit 13 to the liquid jet head 12 is stopped. When the on-off valve (suction valve 34) provided in the suction flow channel 32 is closed, the negative pressure generated by the drive of the suction unit 33 does not reach the cap 31. That is, when the cap 31 forms a closed space in which the nozzle 17 of the liquid jet head 12 is opened, suction of liquid from the liquid jet head 12 due to the negative pressure in the cap 31 is suppressed.

  The liquid ejecting apparatus 11 of the present embodiment is an abnormal state in which the pressure of the suction flow path 32 falls below the first threshold at the time of idle suction operation, and the abnormality that the pressure of the suction flow path 32 is at the second threshold or higher When the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 falls below the third threshold in the state and the negative pressure release operation, the on-off valve (the pressure valve 21 and the suction valve 34) is closed. That is, when the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 is out of the predetermined range, the on-off valve (pressure valve 21, suction valve 34) is closed to allow liquid from the liquid jet head 12 Can be suppressed from flowing out. Therefore, liquid leakage can be suppressed.

  (2) Usually, the empty suction operation is performed in a state where the inside of the cap 31 is opened to the atmosphere, that is, in a state where the cap 31 is at the non-capping position, in order to suction the liquid in the cap 31. At this time, for example, due to malfunction of the cap 31 or the liquid jet head 12, the empty suction operation may be performed in a state where the cap 31 and the liquid jet head 12 contact, that is, a state where the cap 31 is positioned at the capping position. . Therefore, the suction unit 33 may suction the inside of the cap 31 in a state where the cap 31 forms a closed space where the nozzle 17 of the liquid jet head 12 opens. In this case, there is a possibility that the liquid may flow out of the liquid jet head 12 by the drive of the suction unit 33.

  According to the above embodiment, when performing the idle suction operation, if the pressure of the suction flow path 32 falls below the first threshold, the on-off valve (the pressure valve 21, the suction valve 34) is closed and the suction unit 33 is stopped. Do. That is, when the pressure of the suction flow path 32 becomes small during the idle suction operation, the on-off valve is closed and the suction unit 33 is stopped. Accordingly, when the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 is lower than the first threshold value, it is possible to suppress the liquid from flowing out of the liquid jet head 12.

  (3) Usually, the negative pressure accumulation operation is performed with the suction valve 34, which is an on-off valve, closed in order to make the negative pressure accumulation unit 35 a closed space. At this time, for example, due to the malfunction of the suction valve 34, the negative pressure storage operation may be performed in a state where the negative pressure storage unit 35 is not in the closed space. That is, the suction unit 33 may be driven in a state where the negative pressure storage unit 35 is opened to the cap 31 via the suction flow channel 32. In this case, if the cap 31 forms a closed space in which the nozzle 17 of the liquid jet head 12 opens, there is a possibility that the liquid may flow out of the liquid jet head 12 by the drive of the suction unit 33.

  According to the above embodiment, when performing the negative pressure accumulation operation, the suction valve 34 is closed and the suction unit 33 is stopped when the pressure in the suction flow passage 32 becomes equal to or higher than the second threshold. That is, when the pressure in the suction flow path 32 does not decrease during the negative pressure accumulation operation, the suction valve 34 is closed and the suction unit 33 is stopped. Accordingly, when the detection unit 36 detects an abnormal state in which the pressure of the suction flow channel 32 is equal to or higher than the second threshold, it is possible to suppress the liquid from flowing out of the liquid jet head 12.

  (4) For example, when the liquid in the suction flow channel 32 is solidified, the suction flow channel 32 is blocked by the solidified liquid. In this case, even if the suction valve (open / close valve) 34 is opened, the negative pressure of the negative pressure storage unit 35 may not be released. That is, even if the suction valve 34 is opened, the negative pressure storage unit 35 may not be opened to the cap 31 in some cases.

  According to the above embodiment, when performing the negative pressure release operation, the suction valve 34 is closed when the pressure in the suction flow channel 32 falls below the third threshold. That is, the suction valve 34 is closed when the pressure in the suction flow channel 32 remains small during the negative pressure release operation. As a result, even if the suction flow path 32 is suddenly closed, the negative pressure accumulated in the negative pressure accumulation portion 35 can be prevented from reaching the cap 31. When the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 falls below the third threshold, it is possible to suppress the liquid from flowing out of the liquid jet head 12.

  (5) The liquid ejecting apparatus 11 includes the storage unit 42 that stores that the detection unit 36 has detected an abnormal state. Thus, the operation of the liquid ejecting apparatus 11 can be controlled based on the detection unit 36 detecting an abnormal state. For example, when the detection unit 36 stores that an abnormal state has been detected, a recovery operation for recovering the liquid ejecting apparatus 11 can be performed.

  (6) When the storage unit 42 stores that the detection unit 36 detects an abnormal state when the power of the apparatus main body is turned on, the negative pressure accumulation operation and the negative pressure release operation are performed. That is, based on detection of the abnormal state by the detection unit 36, the negative pressure accumulation operation and the negative pressure release operation can be performed as a series of specific operations, whereby the cause of the abnormal state can be identified.

  (7) When the storage unit 42 stores the start of the idle suction operation, the negative pressure accumulation operation, and the negative pressure release operation when the power of the apparatus main body is turned on, the idle suction operation is performed. If a power failure occurs during the empty suction operation, the negative pressure accumulation operation, or the negative pressure release operation, liquid may remain in the cap 31. According to the above embodiment, in the case where the storage unit 42 stores the start of the empty suction operation, the negative pressure accumulation operation, and the negative pressure release operation, the empty suction operation is performed when the apparatus main body is powered on. The liquid in the cap 31 can be aspirated.

  The above embodiment may be modified as shown below. In addition, the configuration included in the above embodiment and the configuration included in the following modification may be arbitrarily combined, or the configurations included in the following modification may be combined arbitrarily.

  As shown in FIG. 10, the negative pressure release operation performed in step S706 of the specific operation may be an operation different from the negative pressure release operation performed at the time of suction cleaning. In the negative pressure release operation in this modification, a new processing operation is provided after step S312.

  After closing the suction valve 34 in step S312, the control unit 41 executing the negative pressure release operation in step S706 of the specific operation determines whether the pressure in the suction flow channel 32 is equal to or higher than the fourth threshold in step S321. Determine. At this time, the control unit 41 compares the pressure of the suction flow path 32 detected by the detection unit 36 with the fourth threshold stored in the storage unit 42.

  The fourth threshold is a value smaller than the third threshold. When the pressure of the suction flow path 32 becomes equal to or higher than the fourth threshold in step S321, the control unit 41 shifts the process to step S322. In step S321, when the pressure of the suction flow path 32 is lower than the fourth threshold in step S321, the control unit 41 shifts the processing to step S323.

  In step S322, the control unit 41 sets an error flag. That is, the control unit 41 causes the storage unit 42 to store that the detection unit 36 has detected an abnormal state. After completing the process of step S322, the control unit 41 ends the negative pressure release operation as a negative pressure release error, and ends the specific operation. When a negative pressure release error occurs, the liquid ejecting apparatus 11 does not receive an operation unless the power is turned on again. The same applies to the process of step S323.

  The cause of the negative pressure release error in the negative pressure release operation of step S706 is the malfunction of the cap 31 or the malfunction of the suction valve 34. If the cap 31 is malfunctioning, the cap 31 is located at the capping position, so the liquid is sucked from the nozzle 17. Thereby, the pressure of the suction flow path 32 becomes a little large.

  If the suction valve 34 is malfunctioning, the pressure in the suction flow path 32 does not change because the suction valve 34 is closed. That is, when the suction valve 34 has a malfunction, the pressure in the suction passage 32 is smaller than when the cap 31 has a malfunction. Thereby, in step S321, when the pressure of the suction flow path 32 is equal to or higher than the fourth threshold value, it can be identified that the cap 31 has a malfunction. In step S321, when the pressure of the suction flow path 32 is lower than the fourth threshold, it can be specified that at least the suction valve 34 has malfunctioned.

  When the detection unit 36 detects an abnormal state, the pressure valve 21 may be operated instead of the suction valve 34. For example, when the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 falls below the first threshold during the idle suction operation, the pressure valve 21 may be controlled to close. For example, when the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 is equal to or higher than the second threshold during the negative pressure accumulation operation, the pressure valve 21 may be controlled to close. For example, when the detection unit 36 detects an abnormal state in which the pressure of the suction flow path 32 falls below the third threshold during the negative pressure releasing operation, the pressure valve 21 may be controlled to close.

  When the detection unit 36 detects an abnormal state, the supply of the liquid flowing from the liquid storage unit 13 to the liquid jet head 12 is stopped by closing the pressurizing valve 21. Therefore, the leakage of the liquid can be suppressed.

The pressure valve 21 may be operated together with the suction valve 34 when the detection unit 36 detects an abnormal state. This can further suppress the liquid leakage.
The operation of the suction valve 34 may be switched to the operation of the pressure valve 21 when there is a possibility that the suction valve 34 has a malfunction.

  The liquid ejecting apparatus 11 may not include the suction valve 34. In this case, although the negative pressure accumulation operation and the negative pressure release operation can not be performed, the liquid can be suctioned from the nozzle 17 by driving the suction unit 33 with the cap 31 positioned at the capping position. By driving the suction unit 33 in a state where the cap 31 is located at the non-capping position, the empty suction operation can be performed. That is, the suction cleaning can be performed without the negative pressure accumulation operation and the negative pressure release operation. When the detection unit 36 detects an abnormal state, leakage of liquid can be suppressed by closing the pressure valve 21.

The pressure valve 21 may not be provided. In this case, although choke cleaning can not be performed, operations such as an empty suction operation, a negative pressure accumulation operation, and a negative pressure release operation can be performed.
-At least one of the pressure valve 21 and the suction valve 34 may be provided. In other words, the on-off valve capable of opening and closing the flow path may be provided in at least one of the supply flow path 19 and the suction flow path 32. When the detection unit 36 detects an abnormal state, leakage of the liquid can be suppressed by closing at least one of the supply flow passage 19 and the suction flow passage 32.

The negative pressure storage unit 35 may not be provided. In this case, the negative pressure accumulation operation is an operation of accumulating negative pressure in the suction flow channel 32. The negative pressure releasing operation is an operation of releasing the negative pressure of the suction flow path 32.
The release valve 39 may not be provided.

The storage unit 42 may be separately provided for storing the in-operation flag and for storing the error flag.
The storage unit 42 may not store the operating flag.

The storage unit 42 may not store the error flag.
The detection unit 16 may be configured to always detect whether or not there is a liquid leakage while the power of the liquid ejection device 11 is turned on. The detection by the detection unit 16 may be performed at any timing. When the detection unit 16 detects liquid leakage, that is, when a leakage error occurs, it is preferable to close the on-off valve (the pressure valve 21 and the suction valve 34) and stop the suction unit 33.

The detection unit 36 may be attached to the suction flow channel 32. In this case, the detection unit 36 is located downstream of the suction valve 34.
The liquid ejecting apparatus 11 may not include the pressurizing unit 14.

  The liquid jetted by the liquid jet head 12 is not limited to ink, and may be, for example, a liquid in which particles of a functional material are dispersed or mixed in the liquid. For example, the liquid jet head 12 jets a liquid containing, in the form of dispersion or dissolution, a material such as an electrode material or a coloring material (pixel material) used in the manufacture of a liquid crystal display, an EL (electroluminescence) display and a surface emitting display. You may

In the following, technical ideas and their effects and advantages which are grasped from the above-described embodiment and the modification will be described.
[Thought 1]
A liquid jet head which jets a liquid supplied from a liquid storage unit via a supply flow path from a nozzle;
A cap configured to be capable of coming into contact with the liquid jet head and capable of forming a closed space in which the nozzle opens;
A suction unit capable of suctioning the inside of the cap via a suction flow path;
A detection unit capable of detecting a pressure state of the suction passage;
And an open / close valve provided in at least one of the supply flow path and the suction flow path and capable of opening and closing the flow path,
A liquid jet apparatus characterized in that the on-off valve is closed when the detection unit detects an abnormal state in which the pressure of the suction flow path is out of a predetermined range.

  When the on-off valve provided in the supply flow path is closed, the supply of the liquid flowing from the liquid storage unit to the liquid jet head is stopped. When the on-off valve provided in the suction flow path is closed, the negative pressure generated by the drive of the suction portion does not reach the cap. That is, when the cap forms a closed space in which the nozzle of the liquid jet head opens, the suction of the liquid from the liquid jet head due to the negative pressure in the cap is suppressed.

  According to the above configuration, when the detection unit detects an abnormal state in which the pressure of the suction flow path is out of the predetermined range, it is possible to suppress the liquid from flowing out from the liquid jet head by closing the on-off valve. Therefore, liquid leakage can be suppressed.

[Thought 2]
When performing an idle suction operation in which the suction unit is driven to suction the liquid in the cap, the detection unit detects the abnormal state in which the pressure in the suction channel falls below a first threshold over a predetermined time. The liquid ejecting apparatus according to [Thought 1], characterized in that, when it is detected, the on-off valve is closed and the suction unit is stopped.

  Usually, the empty suction operation is performed with the inside of the cap open to the atmosphere to aspirate the liquid in the cap. At this time, for example, due to malfunction of the cap or the liquid ejecting head, the idle suction operation may be performed in a state where the cap and the liquid ejecting head are in contact with each other. Therefore, the suction unit may suction the inside of the cap while the cap forms a closed space where the nozzle of the liquid jet head opens. In this case, there is a possibility that the liquid may flow out of the liquid jet head due to the drive of the suction unit.

  According to the above configuration, when performing the idle suction operation, when the pressure in the suction flow channel falls below the first threshold, the on-off valve is closed and the suction unit is stopped. That is, when the pressure in the suction flow channel decreases during the idle suction operation, the on-off valve is closed and the suction unit is stopped. Accordingly, it is possible to suppress the liquid from flowing out from the liquid jet head when the detection unit detects an abnormal state in which the pressure of the suction flow path is lower than the first threshold during the idle suction operation.

[Thought 3]
A negative pressure storage unit having a predetermined volume and communicating with the suction channel;
The on-off valve is provided between the negative pressure accumulation portion and the cap in the suction flow path,
When performing a negative pressure accumulation operation in which the suction unit is driven to accumulate negative pressure in the negative pressure accumulation unit, the pressure in the suction channel is maintained even if the suction unit continues suctioning for a predetermined time. The liquid ejecting apparatus according to [Consideration 2], wherein the on-off valve is closed and the suction unit is stopped when the detection unit detects the abnormal state in which the threshold value is 2 or more.

  Usually, the negative pressure accumulation operation is performed with the on-off valve closed in order to make the negative pressure accumulation part a closed space. At this time, the negative pressure storage operation may be performed in a state where the negative pressure storage unit is not in the closed space due to, for example, an operation failure of the on-off valve. That is, the suction unit may be driven in a state where the negative pressure accumulation unit is opened to the cap via the suction flow channel. In this case, if the cap forms a closed space in which the nozzle of the liquid jet head opens, there is a possibility that the liquid may flow out of the liquid jet head due to the drive of the suction unit.

  According to the above configuration, when performing the negative pressure accumulation operation, when the pressure in the suction flow passage is equal to or higher than the second threshold, the on-off valve is closed and the suction unit is stopped. That is, when the pressure in the suction passage does not decrease during the negative pressure accumulation operation, the on-off valve is closed and the suction unit is stopped. Accordingly, it is possible to suppress the liquid from flowing out from the liquid jet head when the detection unit detects an abnormal state in which the pressure in the suction flow path is equal to or higher than the second threshold during the negative pressure accumulation operation.

[Thought 4]
When performing a negative pressure releasing operation for releasing the negative pressure accumulated in the negative pressure accumulation portion, the pressure in the suction flow path is set to be constant even when a predetermined time has elapsed after controlling the open / close valve to open. The liquid ejecting apparatus according to [Thought 3], wherein the on-off valve is closed when the detection unit detects the abnormal state less than a threshold value.

For example, when the liquid in the suction channel is solidified, the solidified liquid blocks the suction channel. In this case, even if the on-off valve is opened, the negative pressure of the negative pressure storage unit may not be released.
According to the above configuration, when the negative pressure release operation is performed, the on-off valve is closed when the pressure in the suction passage is lower than the third threshold. That is, the open / close valve is closed when the pressure in the suction passage remains small during the negative pressure release operation. As a result, even if the suction flow channel is suddenly closed, it is possible to suppress the negative pressure accumulated in the negative pressure accumulation portion from reaching the cap. In the negative pressure releasing operation, when the detection unit detects an abnormal state in which the pressure in the suction flow path falls below the third threshold, it is possible to suppress the liquid from flowing out from the liquid jet head.

[Thought 5]
The liquid ejecting apparatus according to [Thought 4], further comprising: a storage unit that stores that the detection unit has detected the abnormal state.

According to this configuration, the operation of the liquid ejecting apparatus can be controlled based on the detection unit detecting an abnormal state.
[Thought 6]
The apparatus is characterized in that the negative pressure accumulation operation and the negative pressure release operation are performed when the storage unit stores that the detection unit has detected the abnormal state when the power of the apparatus main body is turned on. The liquid ejection device according to [Thought 5].

According to this configuration, it is possible to identify the cause of the abnormal state by executing the negative pressure accumulation operation and the negative pressure release operation based on the detection unit detecting the abnormal state.
[Thought 7]
The storage unit can store the start of the empty suction operation, the negative pressure accumulation operation, the start of the negative pressure release operation, and the empty suction operation, the negative pressure accumulation operation, the negative pressure release operation The memory of the start of the operation can be reset at the end of the
When the storage unit stores the start of the operation when the power supply of the apparatus main body is turned on, the idle suction operation is performed. The liquid ejecting apparatus according to [Thought 5] or [Thought 6] .

  For example, liquid may remain in the cap if a power failure occurs during the execution of an empty suction operation, a negative pressure accumulation operation, or a negative pressure release operation. According to the above configuration, when the storage unit stores the start of the empty suction operation, the negative pressure accumulation operation, and the negative pressure release operation, the inside of the cap is performed to execute the empty suction operation when the power of the apparatus main body is turned on Liquid can be aspirated.

  DESCRIPTION OF SYMBOLS 11 ... Liquid ejection apparatus, 12 ... Liquid ejection head, 13 ... Liquid accommodation part, 14 ... Pressurization part, 15 ... Maintenance mechanism, 16 ... Detection part, 17 ... Nozzle, 18 ... Nozzle surface, 19 ... Supply flow path, 21 ... pressurization valve (open / close valve), 22 ... one-way valve, 31 ... cap, 32 ... suction flow path, 33 ... suction section, 34 ... suction valve (open / close valve), 35 ... negative pressure storage section, 36 ... detection section , 37: waste liquid storage unit, 38: drive mechanism, 39: release valve, 41: control unit, 42: storage unit, 99: medium.

Claims (7)

A liquid jet head which jets a liquid supplied from a liquid storage unit via a supply flow path from a nozzle;
A cap configured to be capable of coming into contact with the liquid jet head and capable of forming a closed space in which the nozzle opens;
A suction unit capable of suctioning the inside of the cap via a suction flow path;
A detection unit capable of detecting a pressure state of the suction passage;
And an open / close valve provided in at least one of the supply flow path and the suction flow path and capable of opening and closing the flow path,
A liquid jet apparatus characterized in that the on-off valve is closed when the detection unit detects an abnormal state in which the pressure of the suction flow path is out of a predetermined range.   When performing an idle suction operation in which the suction unit is driven to suction the liquid in the cap, the detection unit detects the abnormal state in which the pressure in the suction channel falls below a first threshold over a predetermined time. The liquid ejecting apparatus according to claim 1, wherein when the detection is detected, the on-off valve is closed and the suction unit is stopped. A negative pressure storage unit having a predetermined volume and communicating with the suction channel;
The on-off valve is provided between the negative pressure accumulation portion and the cap in the suction flow path,
When performing a negative pressure accumulation operation in which the suction unit is driven to accumulate negative pressure in the negative pressure accumulation unit, the pressure in the suction channel is maintained even if the suction unit continues suctioning for a predetermined time. The liquid ejecting apparatus according to claim 2, wherein the on-off valve is closed and the suction unit is stopped when the detection unit detects the abnormal state which is equal to or greater than two threshold values.   When performing a negative pressure releasing operation for releasing the negative pressure accumulated in the negative pressure accumulation portion, the pressure in the suction flow path is set to be constant even when a predetermined time has elapsed after controlling the open / close valve to open. 4. The liquid ejecting apparatus according to claim 3, wherein the on-off valve is closed when the detection unit detects the abnormal state below a threshold value.   The liquid ejecting apparatus according to claim 4, further comprising: a storage unit that stores information that the detection unit detects the abnormal state.   The apparatus is characterized in that the negative pressure accumulation operation and the negative pressure release operation are performed when the storage unit stores that the detection unit has detected the abnormal state when the power of the apparatus main body is turned on. The liquid ejecting apparatus according to claim 5. The storage unit can store the start of the empty suction operation, the negative pressure accumulation operation, the start of the negative pressure release operation, and the empty suction operation, the negative pressure accumulation operation, the negative pressure release operation The memory of the start of the operation can be reset at the end of the
7. The liquid ejecting apparatus according to claim 5, wherein the idle suction operation is performed when the storage unit stores the start of the operation when power of the apparatus main body is turned on.