JP6672773B2 - Liquid ejecting apparatus and maintenance method for liquid ejecting apparatus - Google Patents

Description

  The present invention relates to a liquid ejecting apparatus such as an ink jet printer and a maintenance method for the liquid ejecting apparatus.

  2. Description of the Related Art Conventionally, as an example of a liquid ejecting apparatus, an ink jet printer that performs printing by ejecting ink (liquid) supplied from an ink tank (liquid supply source) to a medium from an ink jet head (liquid ejecting unit) is known. . Some of such printers are provided with a damper (pressure adjusting mechanism) for adjusting the pressure of ink supplied to the inkjet head (for example, see Patent Document 1).

  The damper includes an ink path (communication path) that connects the tank-side liquid chamber (liquid inflow section) and the head-side liquid chamber (liquid storage section), and a valve (open / close valve) that opens and closes the ink path. . The valve is configured to open according to the pressure of a variable pressure chamber formed between the head-side liquid chamber and the flexible membrane (diaphragm). That is, the valve in the ink path closes when the pressure in the tank-side liquid chamber becomes higher than the pressure in the variable pressure chamber by a predetermined value or more.

  Then, for example, when performing so-called pressure cleaning in which ink is supplied from an ink tank to the inkjet head under pressure and discharged from the nozzles, it is necessary to forcibly open the valve of the damper. That is, when performing pressure cleaning, it is necessary to maintain the valve open state by continuing to pressurize the variable pressure chamber.

JP 2009-178889 A

  By the way, in the printer as described above, when the pressure cleaning is performed, the volume of the head side liquid chamber increases with the closing of the valve after the pressure cleaning. There is a problem that it is sucked into the nozzle together with foreign matter and bubbles.

  These problems are not limited to ink jet printers that perform printing by ejecting ink from nozzles, but are generally common to liquid ejecting apparatuses that include a pressure adjusting mechanism that adjusts the pressure of liquid.

  The present invention has been made by paying attention to such problems existing in the related art. The purpose is to supply the pressurized liquid to the liquid ejecting unit and perform pressure cleaning in which the liquid is forcibly discharged from the nozzle. It is another object of the present invention to provide a liquid ejecting apparatus and a method for maintaining the liquid ejecting apparatus, which can prevent the liquid ejecting apparatus from being drawn into the nozzle.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
A liquid ejecting apparatus that solves the above-mentioned problem includes a liquid supply path capable of supplying the liquid from a liquid supply source to a liquid ejecting unit that ejects liquid from a nozzle by driving an actuator, and a pressure adjustment provided in the liquid supply path. A mechanism, a liquid inflow portion into which the liquid supplied from the liquid supply source flows, and a liquid storage portion capable of storing the liquid therein and having an internal volume that changes by displacement of a diaphragm portion. And a communication path for communicating the liquid inflow portion with the liquid storage portion and a pressure applied to a first surface of the diaphragm portion that is an inner surface of the liquid storage portion becomes an outer surface of the liquid storage portion of the diaphragm portion. When the pressure applied to the communication path is lower than the pressure applied to the second surface and the difference between the pressure applied to the first surface and the pressure applied to the second surface is equal to or greater than a predetermined value. A pressure adjusting mechanism having an on-off valve that changes from a closed state in which a liquid inflow portion and the liquid storage portion are not in communication with each other to an open state in which the liquid inflow portion and the liquid storage portion are in communication, and the diaphragm portion By pressing in the direction in which the volume of the liquid storage portion is reduced, a pressing mechanism that opens the on-off valve, a pressurizing mechanism that can pressurize the liquid supplied to the pressure adjusting mechanism, A wiping member capable of wiping a nozzle forming surface on which the nozzle is formed in the liquid ejecting unit, and the on-off valve is opened by pressing the diaphragm unit with the pressing mechanism, and the liquid is supplied to the pressurizing mechanism. A controller configured to supply the liquid in a pressurized state to the liquid ejecting unit by being pressurized and discharge the liquid from the nozzle, and then cause the wiping member to wipe the nozzle forming surface. .

  According to this configuration, the liquid pressurized by the pressurizing mechanism is supplied to the liquid ejecting unit, and after performing the pressure cleaning for forcibly discharging the liquid from the nozzle, the wiping member wipes the nozzle forming surface. A meniscus can be formed in the nozzle. Therefore, after the pressure cleaning is performed, it is possible to suppress the liquid attached to the vicinity of the nozzle opening on the nozzle forming surface from being sucked into the nozzle together with foreign matter and bubbles.

  In the liquid ejecting apparatus, the pressurizing mechanism is capable of pressurizing a predetermined amount of the liquid, and the control unit is configured to pressurize the predetermined amount of the liquid by the pressurizing mechanism so that the pressurized state is increased. The predetermined amount of the liquid is supplied to the liquid ejecting unit, and after the discharge of the liquid from the nozzle is stopped, the wiping member is caused to wipe the nozzle forming surface, and then the pressing mechanism presses the diaphragm unit. It is preferable to close the on-off valve by releasing the state.

  Normally, when a predetermined amount of pressurized liquid is discharged from the nozzle, the level of pressurization of the liquid supplied along with the discharge of the liquid decreases, and eventually the pressure level is such that the liquid is not discharged from the nozzle. . By wiping the nozzle forming surface by the wiping member in this state, the meniscus is formed in the nozzle at an internal pressure higher than the internal pressure of the liquid ejecting unit at the time of normal meniscus formation, and the liquid is opened by the closing operation of the on-off valve. When the internal pressure of the injection unit is reduced, it is possible to prevent meniscus in the nozzle from breaking and air or the like from being drawn into the nozzle.

  In the liquid ejecting apparatus, the control unit supplies the liquid in a pressurized state to the liquid ejecting unit by discharging the liquid from the nozzle by pressurizing the liquid by the pressurizing mechanism, and causes the pressing mechanism to After the supply of the liquid in the pressurized state to the liquid ejecting unit is stopped by closing the on-off valve by releasing the pressed state of the diaphragm, the wiping member may wipe the nozzle forming surface. preferable.

  According to this configuration, when the on-off valve is closed while the pressurized liquid is being discharged from the nozzle, the pressurized liquid of the liquid ejecting unit is discharged from the nozzle even after the on-off valve is closed, and the nozzle is eventually The pressure level is such that no liquid is discharged from the liquid. By wiping the nozzle forming surface with the wiping member in this state, a meniscus can be formed in the nozzle at an internal pressure higher than the internal pressure of the liquid ejecting unit at the time of normal meniscus formation. For this reason, when the internal pressure of the liquid ejecting unit decreases due to the valve closing operation of the on-off valve, it is possible to prevent meniscus in the nozzle from breaking and air or the like from being drawn into the nozzle.

  In the liquid ejecting apparatus, a cap that can be capped is provided in a region including the nozzle of the liquid ejecting unit, and the control unit applies the liquid to the pressurizing mechanism with the cap capped the region. The liquid in a pressurized state is supplied to the liquid ejecting unit by being pressed and discharged from the nozzle, and after the discharge of the liquid from the nozzle is stopped, the capping state of the region by the cap is released, It is preferable that the wiping member wipes the nozzle forming surface.

  According to this configuration, when the liquid is discharged from the nozzle in a state where the region including the nozzle of the liquid ejecting unit is capped by the cap, the pressure in the cap increases, so that a resistance that prevents the liquid from being discharged from the nozzle occurs I do. Therefore, the pressure level when the liquid is no longer discharged from the nozzle is higher than when no capping is performed. Even if the capping state by the cap is released in this state, it is difficult for air or the like to be drawn into the nozzle. Thereafter, by wiping the nozzle forming surface by the wiping member, a meniscus can be formed in the nozzle at an internal pressure higher than the internal pressure of the liquid ejecting unit at the time of normal meniscus formation. For this reason, when the internal pressure of the liquid ejecting unit decreases due to the valve closing operation of the on-off valve, it is possible to prevent meniscus in the nozzle from breaking and air or the like from being drawn into the nozzle.

  In the liquid ejecting apparatus, the cap has an atmosphere release valve that can switch a closed space formed when the area is capped between a communicating state communicating with the atmosphere and a non-communicating state not communicating with the atmosphere. It is preferable that the control unit switches the air release valve from the communication state to the non-communication state during a certain time during the discharge of the liquid from the nozzle and when the cap is released from the capping state of the region.

  According to this configuration, the liquid is discharged from the nozzle in a state where the air release valve is in a communication state and the area including the nozzle of the liquid ejecting unit is capped by the cap, and the air release valve is switched to a non-communication state in the middle, The pressure in the cap can be changed. That is, by changing the timing of switching the atmosphere release valve from the communicating state to the non-communicating state, the degree of increase in the pressure in the cap can be adjusted.

  A maintenance method for a liquid ejecting apparatus that solves the above problem is provided in a liquid supply path that can supply the liquid from a liquid supply source to a liquid ejecting unit that ejects liquid from a nozzle by driving an actuator, and the liquid supply path. A pressure adjusting mechanism, wherein a liquid inflow portion into which the liquid supplied from the liquid supply source flows, and a liquid capable of containing the liquid therein and whose internal volume changes due to displacement of a diaphragm portion A storage portion, a communication path for communicating the liquid inflow portion with the liquid storage portion, and a pressure applied to a first surface serving as an inner surface of the liquid storage portion in the diaphragm portion. When the difference between the pressure applied to the first surface and the pressure applied to the second surface is lower than the pressure applied to the second surface serving as the outer surface and the difference between the pressure applied to the second surface is equal to or more than a predetermined value, A pressure adjusting mechanism having an on-off valve that is in a valve-open state in which the liquid inflow portion and the liquid storage portion communicate with the liquid inflow portion and the liquid storage portion from a valve-closed state in which the liquid inflow portion and the liquid storage portion are not in communication with each other; A pressure mechanism that opens the on-off valve by pressing the diaphragm in a direction in which the volume of the liquid container decreases, and a pressurizing mechanism that can pressurize the liquid supplied to the pressure adjusting mechanism. A maintenance method for a liquid ejecting apparatus, comprising: a pressure mechanism; and a wiping member capable of wiping a nozzle forming surface of the liquid ejecting unit where the nozzle is formed, wherein the pressing mechanism presses the diaphragm. After the on-off valve is opened and the liquid pressurized by the pressurizing mechanism is supplied to the liquid ejecting unit and discharged from the nozzle, the liquid is pressed forward by the wiping member. It wipes the nozzle forming surface.

  According to this configuration, the liquid pressurized by the pressurizing mechanism is supplied to the liquid ejecting unit, and after performing the pressure cleaning for forcibly discharging the liquid from the nozzle, the wiping member wipes the nozzle forming surface. A meniscus can be formed in the nozzle. Therefore, after the pressure cleaning is performed, it is possible to suppress the liquid attached to the vicinity of the nozzle opening on the nozzle forming surface from being sucked into the nozzle together with foreign matter and bubbles.

FIG. 2 is a schematic diagram of the liquid ejecting apparatus according to the first embodiment. FIG. 3 is a schematic plan view of a print area and a non-print area. FIG. 3 is a schematic diagram of a pressure adjusting device and a supply mechanism in a state where an on-off valve is closed. FIG. 2 is a schematic diagram of a plurality of pressure adjusting devices and a pressure adjusting unit. FIG. 2 is a schematic diagram of a pressure adjusting device and a supply mechanism in a state where an on-off valve is opened. FIG. 6 is an exploded perspective view of a pressure adjusting device according to a second embodiment. FIG. 3 is a perspective view of a pressure adjusting device. FIG. 8 is a perspective view when FIG. 7 is viewed from another angle. The side view of FIG. FIG. 10 is a side view when FIG. 9 is viewed from the opposite side. FIG. 3 is a schematic diagram of a pressure adjusting unit. Sectional drawing of the pressure regulation apparatus of a valve closed state. Sectional drawing of the pressure regulation apparatus of a valve-open state. FIG. 10 is an enlarged schematic cross-sectional view of a main part showing a state when capping of a liquid ejecting unit is performed in Modification Example 2. FIG. 13 is an enlarged schematic cross-sectional view of a main part showing a state when capping of a liquid ejecting unit is performed in a third modification. FIG. 14 is an enlarged schematic cross-sectional view of a main part illustrating a state when capping of a liquid ejecting unit is performed in a fourth modification. FIG. 15 is a side view of a pressing mechanism according to a sixth modification.

(1st Embodiment)
Hereinafter, a first embodiment of a liquid ejecting apparatus will be described with reference to the drawings.
As shown in FIG. 1, for example, a liquid ejecting apparatus 11 such as an ink jet printer includes a liquid ejecting unit 12 that ejects a liquid such as ink, and a supply mechanism 14 that supplies a liquid from a liquid supply source 13 to the liquid ejecting unit 12. And Further, the liquid ejecting apparatus 11 includes a support table 112 disposed at a position facing the liquid ejecting section 12, a transport section 114 that transports a medium 113 such as a sheet in the transport direction Y, and a A printing unit 115 for performing printing by ejecting a liquid onto the medium 113 while moving the medium to X.

  The support base 112 extends in the width direction (scanning direction X) of the medium 113, which is a direction orthogonal (intersecting) to the transport direction Y of the medium 113. The support base 112, the transport unit 114, and the printing unit 115 are assembled to a main body 116 including a housing, a frame, and the like. A cover 117 is provided on the main body 116 so as to be openable and closable.

  The transport unit 114 includes transport roller pairs 118 and 119 disposed upstream and downstream of the support base 112 in the transport direction Y, and a guide plate 120 disposed downstream of the transport roller pair 119 and guiding the medium 113. And Then, when the transport roller pairs 118 and 119 are driven by a transport motor (not shown) and rotate while pinching the medium 113, the medium 113 is supported by the support table 112 and the guide plate 120, and the surface of the support table 112 and It is transported along the surface of the guide plate 120.

  The printing unit 115 includes guide shafts 122 and 123 extending in the scanning direction X, and a carriage 124 guided by the guide shafts 122 and 123 and capable of reciprocating in the scanning direction X. The carriage 124 moves with the driving of a carriage motor (not shown). At least one (two in the present embodiment) liquid ejecting units 12 are attached to the lower end of the carriage 124 on the vertical Z side. These two liquid ejecting units 12 are arranged so as to be separated from each other by a predetermined distance in the scanning direction X and by a predetermined distance in the transport direction Y. Then, each liquid ejecting unit 12 ejects liquid from a plurality of nozzles 19 formed on the nozzle forming surface 18.

  As shown in FIG. 2, a wiper unit 126, a flushing unit 127, and a cap unit 128 are provided in a non-printing area in which the liquid ejecting unit 12 does not face the medium 113 being conveyed in the scanning direction X. ing. The wiper unit 126 has a movable wiping member 130 capable of wiping the nozzle forming surface 18, and a wiping motor 131 serving as a power source of the wiping member 130.

  The wiping member 130 can be constituted by, for example, a cloth wiper or a rubber blade. The wiping member 130 of the present embodiment is configured by a cloth wiper, and moves in the transport direction Y by driving the wiping motor 131 while the liquid ejecting unit 12 is moved to a position where the wiping member 130 can wipe the liquid ejecting unit 12. The wiping of the nozzle forming surface 18 is performed while doing so.

  The flushing unit 127 has a liquid receiving unit 132 that receives the liquid discharged by the flushing from the nozzle 19 of the liquid ejecting unit 12. The liquid receiving section 132 is constituted by a movable belt, and moves by the power of the flushing motor 133. The flushing is an operation of forcibly ejecting (discharging) the liquid from all the nozzles 19 independently of printing for the purpose of preventing and eliminating clogging of the nozzles 19 and the like.

  The cap unit 128 includes two caps 134 in the shape of a closed box with a bottom covering the nozzles 19 of the two liquid ejecting units 12 and a capping motor 135 that moves the cap 134 up and down. Then, the capping motor 135 is driven in a state where the two liquid ejecting units 12 are moved to positions facing the two caps 134, respectively, and the two caps 134 are raised, thereby forming the nozzles of the two liquid ejecting units 12. So-called capping is performed, in which the two caps 134 respectively abut against the surface 18 so as to cover all the nozzles 19. That is, each cap 134 can cap a region including all the nozzles 19 on the nozzle forming surface 18 of each liquid ejecting unit 12.

  As shown in FIG. 3, the liquid ejecting unit 12 includes an ejecting unit filter 16 that captures bubbles and foreign substances in the liquid, and a common liquid chamber 17 that stores the liquid that has passed through the ejecting unit filter 16. Further, the liquid ejecting unit 12 includes a plurality of pressure chambers 20 that allow the plurality of nozzles 19 formed on the nozzle forming surface 18 to communicate with the common liquid chamber 17. A part of the wall surface of the pressure chamber 20 is formed by the vibration plate 21, and the common liquid chamber 17 and the pressure chamber 20 communicate with each other through the communication hole 22. Further, an actuator 24 housed in a housing chamber 23 is provided on a surface of the vibration plate 21 opposite to a portion facing the pressure chamber 20 and at a position different from the common liquid chamber 17.

  The actuator 24 of the present embodiment is configured by a piezoelectric element that contracts when a drive voltage is applied. After the diaphragm 21 is deformed in accordance with the contraction of the actuator 24 due to the application of the drive voltage, when the application of the drive voltage to the actuator 24 is released, the liquid in the pressure chamber 20 whose volume has changed is discharged from the nozzle 19. Injected as drops. That is, the liquid ejecting unit 12 drives the actuator 24 to eject the liquid from the nozzle 19.

  The liquid supply source 13 is, for example, a storage container that can store the liquid, and may be a cartridge that replenishes the liquid by replacing the storage container, or a storage tank that is fixed to the mounting unit 26. . When the liquid supply source 13 is a cartridge, the mounting unit 26 detachably holds the liquid supply source 13. The liquid supply source 13 and the supply mechanism 14 are provided in at least one set (four in the present embodiment) for each type of liquid ejected from the liquid ejecting unit 12.

  The supply mechanism 14 includes a liquid supply path 27 that can supply the liquid from the liquid supply source 13 on the upstream side in the liquid supply direction A to the liquid ejecting unit 12 on the downstream side. Part of the liquid supply path 27 also functions as a circulation path in cooperation with the circulation path forming unit 28. That is, the circulation path forming unit 28 connects the common liquid chamber 17 and the liquid supply path 27. The circulation path forming section 28 is provided with a circulation pump 29 for circulating the liquid in the circulation direction B in the circulation path.

  By moving the liquid in the supply direction A from the liquid supply source 13 toward the liquid supply source 13 from the position where the circulation path forming unit 28 is connected in the liquid supply path 27, the liquid is directed toward the liquid ejection unit 12. A pressurizing mechanism 31 for supplying pressure is provided. Further, in the portion of the liquid supply path 27 that also functions as a circulation path downstream of the position where the circulation path forming section 28 is connected, a filter unit 32, a static mixer 33, a liquid storage section 34, and a A pressure adjusting mechanism 35 is provided.

  The pressurizing mechanism 31 includes a volume pump 38 capable of pressurizing a predetermined amount of liquid by reciprocating a flexible member 37 having flexibility, and an upstream side and a downstream side of the volume pump 38 in the liquid supply path 27. And one-way valves 39 and 40 respectively provided for the two. The positive displacement pump 38 has a pump chamber 41 and a negative pressure chamber 42 separated by a flexible member 37. Further, the volume pump 38 includes a decompression unit 43 for decompressing the negative pressure chamber 42 and an urging member 44 provided in the negative pressure chamber 42 to urge the flexible member 37 toward the pump chamber 41. And

  Further, the one-way valves 39 and 40 allow the flow of the liquid from the upstream side to the downstream side in the liquid supply path 27 and inhibit the flow of the liquid from the downstream side to the upstream side. That is, the pressurizing mechanism 31 can pressurize the liquid supplied to the pressure adjusting mechanism 35 by the urging member 44 urging the liquid in the pump chamber 41 via the flexible member 37. For this reason, the pressing force by which the pressing mechanism 31 pressurizes the liquid is set by the urging force of the urging member 44.

  The filter unit 32 captures air bubbles and foreign substances in the liquid and is provided so as to be exchangeable. The static mixer 33 changes the flow of the liquid, such as a change of direction or a division, to reduce the concentration unevenness in the liquid. The liquid storage section 34 stores the liquid in a variable-volume space urged by the spring 45 to reduce fluctuations in the pressure of the liquid.

Next, the pressure adjusting device 47 will be described.
As shown in FIG. 3, the pressure adjusting device 47 includes a pressure adjusting mechanism 35 provided in the liquid supply path 27 and constituting a part of the liquid supply path 27, and a pressing mechanism 48 for pressing the pressure adjusting mechanism 35. Have. The pressure adjusting mechanism 35 includes a main body 52 having a liquid inflow portion 50 into which the liquid supplied from the liquid supply source 13 via the liquid supply path 27 flows, and a liquid storage portion 51 capable of storing the liquid therein. It has.

  The liquid supply path 27 and the liquid inflow section 50 are partitioned by a wall 53, and communicate with each other by a through hole 54 formed in the wall 53. The through-hole 54 is covered with a filter member 55. Therefore, the liquid in the liquid supply path 27 is filtered by the filter member 55 and flows into the liquid inflow section 50.

  A part of the wall surface of the liquid container 51 is constituted by the diaphragm 56. The diaphragm portion 56 receives the pressure of the liquid in the liquid storage portion 51 on the first surface 56a serving as the inner surface of the liquid storage portion 51, while reducing the atmospheric pressure on the second surface 56b serving as the outer surface of the liquid storage portion 51. receive. For this reason, the diaphragm section 56 is displaced in accordance with the pressure in the liquid storage section 51. Therefore, the volume of the liquid container 51 changes as the diaphragm 56 is displaced. In addition, the liquid inflow section 50 and the liquid storage section 51 are communicated by a communication path 57.

  The pressure adjusting mechanism 35 communicates the liquid inflow section 50 with the liquid storage section 51 in a closed state (a state shown in FIG. 3) in which the liquid inflow section 50 and the liquid storage section 51 are not communicated with each other in the communication path 57. An on-off valve 59 capable of switching between an open state (the state shown in FIG. 5) is provided. The on-off valve 59 has a valve portion 60 that can shut off the communication path 57 and a pressure receiving portion 61 that receives pressure from the diaphragm portion 56, and moves when the pressure receiving portion 61 is pressed by the diaphragm portion 56. That is, the pressure receiving portion 61 also functions as a movable member that can move in a state of being in contact with the diaphragm portion 56 that is displaced in a direction in which the volume of the liquid storage portion 51 is reduced.

  An upstream urging member 62 is provided in the liquid inflow section 50, and a downstream urging member 63 is provided in the liquid storage section 51. Both the upstream urging member 62 and the downstream urging member 63 urge in a direction to close the on-off valve 59. The on-off valve 59 is configured such that the pressure applied to the first surface 56a is lower than the pressure applied to the second surface 56b, and the difference between the pressure applied to the first surface 56a and the pressure applied to the second surface 56b is a predetermined value. (For example, 1 kPa) or more, the valve changes from the closed state to the open state.

  This predetermined value is required for the urging force of the upstream urging member 62, the urging force of the downstream urging member 63, the force required to displace the diaphragm portion 56, and the force required to cut off the communication path 57 by the valve portion 60. This value is determined according to the pressing force (seal load), the pressure in the liquid inflow portion 50 acting on the surface of the valve portion 60, and the pressure in the liquid storage portion 51. That is, the predetermined value increases as the urging force of the upstream urging member 62 and the downstream urging member 63 increases.

  The urging force of the upstream urging member 62 and the downstream urging member 63 is a negative pressure state (for example, the second pressure state) in a range where the pressure in the liquid container 51 can form the meniscus 64 at the gas-liquid interface in the nozzle 19. When the pressure applied to the surface 56b is the atmospheric pressure, the pressure is set to -1 kPa). In this case, the gas-liquid interface is a boundary between the liquid and the gas, and the meniscus 64 is a curved liquid surface formed by the liquid in contact with the nozzle 19. It is preferable that a concave meniscus 64 suitable for ejecting liquid is formed in the nozzle 19.

  The pressing mechanism 48 is capable of adjusting the pressure in the pressure adjusting chamber 66, an expansion / contraction section 67 forming a pressure adjustment chamber 66 on the second surface 56 b side of the diaphragm section 56, a pressing member 68 for pressing the expansion / contraction section 67. And a pressure adjusting section 69. The expansion / contraction unit 67 is formed in a balloon shape by, for example, rubber or resin, and expands or contracts as the pressure of the pressure adjustment chamber 66 is adjusted by the pressure adjustment unit 69. The holding member 68 has a bottomed cylindrical shape, and a part of the expansion / contraction portion 67 is inserted into an insertion hole 70 formed in the bottom.

  The edge of the holding member 68 on the side of the opening 71 on the inner surface is rounded and rounded. The holding member 68 is attached to the pressure adjusting mechanism 35 such that the opening 71 is closed by the pressure adjusting mechanism 35, thereby forming an air chamber 72 that covers the second surface 56 b of the diaphragm 56. The pressure in the air chamber 72 is set to the atmospheric pressure, and the atmospheric pressure acts on the second surface 56b of the diaphragm portion 56.

  That is, the pressure adjusting section 69 expands the expansion / contraction section 67 by adjusting the pressure in the pressure adjusting chamber 66 to a pressure higher than the atmospheric pressure which is the pressure of the air chamber 72. Then, the pressing mechanism 48 presses the diaphragm 56 in a direction in which the volume of the liquid storage unit 51 decreases as the pressure adjusting unit 69 expands the expansion / contraction unit 67. At this time, the expansion / contraction portion 67 of the pressing mechanism 48 presses a region of the diaphragm portion 56 where the pressure receiving portion 61 contacts. The area of the region of the diaphragm 56 where the pressure receiving portion 61 contacts is larger than the cross-sectional area of the communication path 57.

  As shown in FIG. 4, the pressure adjusting unit 69 includes a pressurizing pump 74 that pressurizes a fluid such as air or water, a connection path 75 that connects the pressurizing pump 74 and the expansion / contraction unit 67, and a connection path 75. And a fluid pressure adjusting unit 77 provided in the apparatus. The downstream side of the connection path 75 is branched into a plurality (four in this embodiment) and connected to the inflation / contraction portions 67 of the plurality (four in this embodiment) of the pressure adjusting devices 47, respectively. . By providing a switching valve for switching between a communication state and a non-communication state of the flow path in each of the plurality of branched flow paths of the connection path 75, the pressurized fluid can be selectively supplied to the plurality of expansion / contraction sections 67. It is also possible to supply.

  That is, the fluid pressurized by the pressurizing pump 74 is supplied to each expansion / contraction section 67 via the connection path 75. The detecting unit 76 detects the pressure of the fluid in the connection path 75, and the fluid pressure adjusting unit 77 is configured by, for example, a safety valve. When the pressure of the fluid in the connection path 75 becomes higher than a predetermined pressure, the fluid pressure adjusting unit 77 automatically opens the valve and discharges the fluid in the connection path 75 to the outside to thereby open the connection path. The pressure of the fluid in 75 is reduced.

  In addition, the liquid ejecting apparatus 11 includes a control unit 78 that controls the driving of the pressurizing pump 74 based on the pressure of the fluid in the connection path 75 detected by the detecting unit 76. The control unit 78 controls the driving of the entire liquid ejecting apparatus 11 as a whole, and controls, for example, the driving of various mechanisms, various motors, various pumps, and the like.

Next, the operation of the pressure adjusting device 47 for adjusting the pressure of the liquid supplied to the liquid ejecting unit 12 will be described.
As shown in FIG. 3, when the liquid ejecting unit 12 ejects the liquid, the liquid stored in the liquid storage unit 51 is supplied to the liquid ejecting unit 12 via the liquid supply path 27. Then, as shown in FIG. 5, when the pressure in the liquid storage portion 51 decreases and the difference between the pressure applied to the first surface 56a and the pressure applied to the second surface 56b of the diaphragm portion 56 becomes a predetermined value or more. Thus, the diaphragm portion 56 bends and deforms in a direction to reduce the volume of the liquid storage portion 51. When the pressure receiving portion 61 is pressed and moved with the deformation of the diaphragm portion 56, the on-off valve 59 is opened.

  Then, since the liquid in the liquid inflow section 50 is pressurized by the pressurizing mechanism 31, the liquid is supplied from the liquid inflow section 50 to the liquid storage section 51, and the pressure in the liquid storage section 51 increases. Thereby, the diaphragm portion 56 is deformed so as to increase the volume of the liquid storage portion 51. When the difference between the pressure applied to the first surface 56a and the pressure applied to the second surface 56b of the diaphragm 56 becomes smaller than a predetermined value, the on-off valve 59 changes from the open state to the closed state, and the liquid Inhibits flow.

  In this manner, the pressure adjusting mechanism 35 adjusts the pressure of the liquid supplied to the liquid ejecting section 12 by displacing the diaphragm section 56, thereby reducing the pressure in the liquid ejecting section 12 that becomes the back pressure of the nozzle 19. adjust.

Next, a description will be given of the operation in the case where the cleaning is performed by forcibly flowing the liquid from the liquid supply source 13 to the liquid ejecting unit 12 for the maintenance of the liquid ejecting unit 12.
As shown in FIG. 4, when the control unit 78 drives the pressurizing pump 74, the pressurized fluid is supplied to the expansion / contraction unit 67. Then, as shown in FIG. 5, the expansion / contraction section 67 to which the fluid has been supplied expands and presses a region of the diaphragm section 56 where the pressure receiving section 61 contacts, thereby opening the on-off valve 59.

  That is, the pressing mechanism 48 opens the on-off valve 59 by moving the pressure receiving portion 61 against the urging force of the upstream urging member 62 and the downstream urging member 63. In this case, since the pressure adjusting units 69 are connected to the expansion / contraction units 67 of the plurality of pressure adjusting devices 47, the open / close valves 59 of all the pressure adjusting devices 47 are opened.

  At this time, since the diaphragm portion 56 is deformed in a direction to reduce the volume of the liquid containing portion 51, the liquid contained in the liquid containing portion 51 is pushed out to the liquid ejecting portion 12 side. That is, the pressure at which the diaphragm 56 presses the liquid container 51 is transmitted to the liquid ejecting unit 12, so that the meniscus 64 is broken and the liquid overflows from the nozzle 19. That is, the pressing mechanism 48 sets the pressure in the liquid storage unit 51 higher than the pressure at which at least one meniscus 64 is broken (for example, the pressure at which the liquid pressure at the gas-liquid interface is 3 kPa higher than the gas pressure). The diaphragm part 56 is pressed so as to be in the position.

  Further, the pressing mechanism 48 opens the on-off valve 59 by pressing the diaphragm portion 56 irrespective of the pressure in the liquid inflow portion 50. In this case, the pressing mechanism 48 presses the diaphragm 56 with a pressing force that is larger than a pressing force generated when a pressure obtained by adding the above-described predetermined value to the pressure at which the pressing mechanism 31 presses the liquid is applied to the diaphragm 56. Press.

  Then, the control unit 78 periodically drives the pressure reducing unit 43 in the open state of the on-off valve 59 by the pressing mechanism 48 pressing the diaphragm unit 56, and thereby the liquid pressurized by the pressurizing mechanism 31. Is supplied to the liquid ejecting unit 12. That is, when the pressure in the negative pressure chamber 42 is reduced by driving the pressure reducing unit 43, the flexible member 37 moves in a direction to increase the volume of the pump chamber 41.

  Then, the liquid flows into the pump chamber 41 from the liquid supply source 13. When the decompression by the decompression unit 43 is released, the flexible member 37 is urged by the urging force of the urging member 44 in a direction to reduce the volume of the pump chamber 41. That is, the liquid in the pump chamber 41 is pressurized by the urging force of the urging member 44 via the flexible member 37, and is supplied to the downstream side of the liquid supply path 27 through the one-way valve 40 on the downstream side. Is done.

  The open state of the on-off valve 59 is maintained while the pressing mechanism 48 is pressing the diaphragm portion 56. Therefore, when the pressurizing mechanism 31 pressurizes the liquid in this state, the pressing force is applied to the liquid inflow portion 50, Pressure cleaning is performed in which the liquid is transmitted to the liquid ejecting unit 12 via the communication path 57 and the liquid storage unit 51 and the liquid is discharged from the nozzle 19.

  When the pressure cleaning is completed, the control unit 78 releases the pressing state of the diaphragm unit 56 by the pressing mechanism 48 in a state where the liquid is pressed by the pressing mechanism 31, and closes the on-off valve 59. To In this case, the control unit 78 drives the actuator 24 of the liquid ejecting unit 12 in the process of changing the on-off valve 59 from the open state to the closed state.

  That is, when the actuator 24 is driven, the liquid is ejected from the nozzle 19 and the ejected liquid is supplied to the liquid ejecting section 12 from the liquid accommodating section 51. The on-off valve 59 is closed with the liquid flowing through the part 51. Thereafter, the control unit 78 causes the wiping member 130 to wipe (wiping) the nozzle forming surface 18 and then drives the actuator 24 to perform flushing. As a result, a meniscus 64 is formed in the nozzle 19.

Next, a manufacturing method for manufacturing the pressure adjusting device 47 by joining the pressure adjusting mechanism 35 and the pressing mechanism 48 will be described.
First, the main body 52 of the present embodiment is formed of a light-absorbing resin (for example, polypropylene or polybutylene terephthalate) that absorbs laser light and generates heat, or a resin colored with a dye that absorbs light. Further, the diaphragm portion 56 is formed by laminating different materials such as polypropylene and polyethylene terephthalate, and has transparency and flexibility for transmitting laser light. The pressing member 68 is formed of a light-transmitting resin (for example, polystyrene or polycarbonate) that transmits laser light. That is, the transparency of the diaphragm portion 56 is higher than the transparency of the main body portion 52 and lower than the transparency of the pressing member 68.

  As shown in FIG. 3, first, the diaphragm portion 56 is clamped by the pressing member 68 in which a part of the expansion / contraction portion 67 is inserted into the insertion hole 70 and the main body 52 (a clamping step). Then, a laser beam is irradiated via the pressing member 68 (irradiation step). Then, the laser beam transmitted through the pressing member 68 is absorbed by the main body 52 and generates heat. The heat generated at this time causes the main body portion 52, the diaphragm portion 56, and the pressing member 68 to be welded. Therefore, the holding member 68 also functions as a jig for holding the diaphragm 56 when manufacturing the pressure adjusting device 47.

As described above, according to the first embodiment, the following effects can be obtained.
(1) Even if the pressure in the liquid inflow section 50 fluctuates, the pressing mechanism 48 can open the on-off valve 59 regardless of the pressure in the liquid inflow section 50. Therefore, the liquid can be stably supplied to the liquid ejecting unit 12.

  (2) The pressure adjustment unit 69 adjusts the pressure in the pressure adjustment chamber 66 to press the diaphragm 56 in a direction in which the volume of the liquid storage unit 51 decreases. Therefore, the pressing mechanism 48 can appropriately press the diaphragm portion 56.

  (3) The pressure adjusting section 69 presses the diaphragm section 56 in a direction in which the volume of the liquid storage section 51 decreases by expanding the expansion / contraction section 67. Therefore, the pressing mechanism 48 can appropriately press the diaphragm portion 56.

  (4) During pressure cleaning in which the liquid supplied from the liquid supply source 13 is discharged from the nozzle 19, the liquid is supplied under a pressure higher than the pressure at which the meniscus 64 is broken. In this regard, in the present embodiment, since the pressure in the liquid storage unit 51 at which the diaphragm unit 56 is pressed by the pressing mechanism 48 is higher than the pressure at which the meniscus 64 is broken, the on-off valve 59 is opened even when pressure cleaning is performed. State.

  (5) Since the pressing mechanism 48 presses the region of the diaphragm 56 where the pressure receiving portion 61 contacts, deformation of the diaphragm 56 can be limited as compared with the case where the pressure adjusting mechanism 35 does not have the pressure receiving portion 61. Therefore, when the pressing mechanism 48 releases the pressing of the diaphragm portion 56 and the diaphragm portion 56 is displaced in a direction to increase the volume of the liquid storage portion 51, the possibility that gas or the like is drawn from the nozzle 19 can be reduced.

  (6) By supplying the liquid pressurized by the pressurizing mechanism 31 to the liquid ejecting unit 12 in a state where the on-off valve 59 is opened, the liquid ejecting unit 12 can be suitably cleaned.

  (7) The diaphragm portion 56 pressed by the pressing mechanism 48 is displaced in a direction to reduce the volume of the liquid storage portion 51 to open the on-off valve 59. Therefore, when the pressing of the pressing mechanism 48 is released, the diaphragm is released. The section 56 tends to be displaced in a direction to increase the volume of the liquid storage section 51. In this case, since the liquid pressurized by the pressurizing mechanism 31 is supplied to the pressure adjusting mechanism 35, it is possible to reduce a possibility that the liquid is drawn from the liquid ejecting unit 12 side. Therefore, the possibility that gas or the like is drawn from the nozzle 19 can be reduced.

  (8) The liquid ejecting unit 12 ejects the liquid supplied from the liquid supply source 13 from the nozzle 19 by driving the actuator 24. That is, since the liquid can flow from the liquid supply source 13 toward the liquid ejecting unit 12, the possibility that gas or the like is drawn from the nozzle 19 can be reduced.

  (9) The on-off valve 59 can be opened regardless of the pressure of the liquid inflow section 50. For this reason, for example, even when the pressure of the liquid inflow unit 50 becomes high when the recording process is performed on the medium 113 by ejecting the liquid from the nozzle 19, the liquid ejection unit 12 is opened by opening the on-off valve 59. Liquid can be supplied. Therefore, it is possible to suppress the interruption of the recording process and the deterioration of the recording quality due to the interruption of the recording process.

  (10) Since the fluid pressure adjusting unit 77 is provided in the connection path 75, even when the pressure of the connection path 75 is increased due to unexpected driving of the pressurizing pump 74, the pressure of the fluid supplied to the expansion / contraction unit 67 is reduced. Can be adjusted. Therefore, the possibility that unexpected pressure is applied to the expansion / contraction section 67 can be reduced.

  (11) After the open / close valve 59 is changed from the open state to the closed state, wiping and flushing are performed, whereby the meniscus 64 can be adjusted. For example, when the diaphragm portion 56 moves in a direction to increase the volume of the liquid storage portion 51, a region not in contact with the pressure receiving portion 61 moves in a direction to decrease the volume of the liquid storage portion 51, and the liquid overflows from the nozzle 19. Even in the case where the meniscus 64 has been lost, the meniscus 64 can be prepared.

(2nd Embodiment)
Next, a second embodiment of the liquid ejecting apparatus will be described with reference to the drawings.
In the second embodiment, the pressure adjusting device 47 in the first embodiment is changed to a pressure adjusting device 200 shown in FIGS. 6 and 7, and the other points are substantially the same as those in the first embodiment. The same components are denoted by the same reference numerals, and the description thereof will not be repeated.

  As shown in FIGS. 6 and 7, the pressure adjusting device 200 includes an air chamber forming unit 201, a pressure adjusting mechanism forming unit 202, a bottom plate member 203, a connecting portion forming unit 204, and two lever units 205. It is formed by assembling.

  The connection part forming unit 204 includes a main body part 206 and a connection film 207 attached so as to cover an outer surface of the main body part 206. On the upper surface of the main body 206, a first liquid connection 208 and a second liquid connection 209 to which two of the plurality of liquid supply paths 27 are respectively connected, and a pressure connection 211 to which a pressure adjustment unit 210 is connected. And protruding. On the inner surface of the main body 206, a first liquid outlet 212, a second liquid outlet 213, and a pressure supply unit, which communicate with the first liquid connection 208, the second liquid connection 209, and the pressure connection 211, respectively. 214 are protruded.

  Three grooves (not shown) are formed on the outer surface of the main body 206 of the connection part forming unit 204, and three flow paths (not shown) are formed by the three grooves and the connection film 207. These three flow paths (not shown) include a first liquid connection part 208, a second liquid connection part 209, and a pressure connection part 211, a first liquid derivation part 212, a second liquid derivation part 213, and a pressure supply part. 214 are connected respectively.

  The air chamber forming unit 201 includes a main body 215 and flexible air chamber films 216 attached to both side surfaces of the main body portion 215 so as to cover the entire side surfaces. An air introduction unit 217 to which the pressure supply unit 214 is connected is provided on a side surface of the main body unit 215 on the connection unit forming unit 204 side. Substantially T-shaped mounting portions 218 to which the lever unit 205 is mounted are protrudingly provided on both sides of the main body 215 near the boundaries with the pressure adjusting mechanism forming unit 202.

  As shown in FIGS. 6 and 8, circular concave portions 219 are respectively formed on both side surfaces of the main body 215 of the air chamber forming unit 201. The space surrounded by each recess 219 and each air chamber film 216 is a pressure adjustment chamber 220 which is an air chamber. A circular portion corresponding to the concave portion 219 in each air chamber film 216 is a flexible wall 221 that forms a part of the pressure adjustment chamber 220. In the present embodiment, a turning power applying unit is configured by the flexible wall 221.

  As shown in FIGS. 9 and 10, grooves 222 are respectively formed on both side surfaces of the main body 215 of the air chamber forming unit 201, and these grooves 222 communicate with each other through through holes 223. The two grooves 222 communicate with the center of the recess 219 located on the opposite side via a through hole 224. An air flow path 225 is formed by a space surrounded by the two grooves 222 and the two air chamber films 216. Therefore, the air passage 225 extends over both side surfaces of the main body 215. The air passage 225 communicates with the air introduction unit 217.

  As shown in FIG. 6, the pressure adjusting mechanism forming unit 202 includes a main body 226 and flexible pressure films 227 attached to both sides of the main body 226 so as to cover the entire sides. Have. A first liquid introduction portion 228 and a second liquid introduction portion 229 to which the first liquid lead-out portion 212 and the second liquid lead-out portion 213 are respectively connected are provided on the side surface of the main body 226 on the side of the connection portion forming unit 204. I have.

  As shown in FIGS. 6 and 8, circular concave portions 230 are respectively formed on both side surfaces of the main body 226 of the pressure adjusting mechanism forming unit 202. The space surrounded by each concave portion 230 and each pressure film 227 is a liquid storage portion 231. A circular portion corresponding to the concave portion 230 in each pressure film 227 is a diaphragm portion 232 that forms a part of the liquid container 231.

  As shown in FIGS. 6 and 10, the lever unit 205 includes a rectangular plate-shaped lever 233 and a torsion spring 235 locked by the locking portion 234 of the lever 233. A mounting hole 236 for mounting the lever unit 205 to the mounting portion 218 is formed at a position slightly closer to one end side of the lever 233 than the center in the longitudinal direction. The lever 233 has a substantially disc-shaped pressing portion 237 at one end in the longitudinal direction on one surface thereof, and a substantially hemispherical pressed portion 238 at the other end.

  When the lever unit 205 is attached to the attachment portion 218 in the attachment hole 236 of the lever 233, the lever unit 205 is rotatable about a fulcrum that is a contact portion of the lever 233 with the attachment portion 218. At this time, the pressing portion 237 faces the center of the diaphragm 232, and the pressed portion 238 contacts the center of the flexible wall 221.

  Further, at this time, the urging force of the torsion spring 235 acts as a resistance force when the lever 233 is rotated in a direction in which the pressing portion 237 approaches the diaphragm portion 232. Therefore, the pressing part 237 is usually separated from the diaphragm part 232.

  As shown in FIG. 11, the pressure adjustment unit 210 includes an annular annular pipe 240, a pump 241 provided in the middle of the annular pipe 240, and an annular pipe 240 provided at a position on the annular pipe 240 opposite to the pump 241. A connection pipe 242 for connecting the pressure connection 240 to the pressure connection part 211 is provided. A second valve V2 is provided between a connection position of the annular pipe 240 and the connection pipe 242 and the pump 241. A third valve V3 is provided at a position of the annular pipe 240 opposite to the second valve V2. I have.

  A base end of a first branch pipe 243 whose distal end side is open to the atmosphere is connected between the second valve V2 and the pump 241 in the annular pipe 240, and a first valve V1 is provided at an intermediate position of the first branch pipe 243. Have been. A base end of a second branch pipe 244 whose distal end is open to the atmosphere is connected between the third valve V3 and the pump 241 in the annular pipe 240, and a fourth valve V4 is provided at an intermediate position of the second branch pipe 244. Have been.

  The pump 241 drives the air in the annular pipe 240 to flow in one direction indicated by an arrow in FIG. Then, the pressure adjustment unit 210 closes the first valve V1 and the third valve V3 and drives the pump 241 in a state where the second valve V2 and the fourth valve V4 are open, so that the pressure connection unit 211 Air is supplied under pressure to pressurize the pressure adjustment chamber 220 (see FIGS. 7 and 8).

  On the other hand, the pressure adjusting unit 210 operates the pump 241 in a state where the first valve V1 and the third valve V3 are opened and the second valve V2 and the fourth valve V4 are closed. The air is sucked to reduce the pressure in the pressure adjustment chamber 220 (see FIGS. 7 and 8).

  Therefore, the pressure adjusting unit 210 functions as a pressurizing and depressurizing device that can simultaneously pressurize and depressurize the two pressure adjusting chambers 220 (see FIGS. 7 and 8) of the pressure adjusting device 200. The first to fourth valves V1 to V4 are constituted by electromagnetic valves, and their opening and closing operations are respectively controlled by the control unit 78 (see FIG. 4).

Next, the pressure adjusting device 200 will be described in detail.
Here, the description will be made mainly based on FIGS. 3 and 12, but in FIG. 3, the description will be made assuming that the pressure adjusting device 47 is replaced with a pressure adjusting device 200 shown in FIG.

  As shown in FIGS. 3 and 12, the pressure adjusting device 200 includes a pressure adjusting mechanism 250 provided in the liquid supply path 27 and constituting a part of the liquid supply path 27, and a pressing mechanism that presses the pressure adjusting mechanism 250. 251 are provided. Therefore, the pressure adjusting device 200 can adjust the pressures of two kinds of liquids by one.

  The pressure adjusting mechanism 250 included in the pressure adjusting mechanism forming unit 202 includes a liquid inflow portion 252 into which the liquid supplied from the liquid supply source 13 via the liquid supply path 27 flows, and a liquid storage portion 231 capable of storing the liquid therein. And a main body 226 formed with the same. The liquid supply path 27 and the liquid inflow portion 252 are partitioned by a wall 247 and communicate with each other by a through hole 248 formed in the wall 247. A filter member 249 is disposed immediately upstream of the through hole 248 in the liquid supply path 27. Therefore, the liquid in the liquid supply path 27 is filtered by the filter member 249 and flows into the liquid inflow section 252.

  The liquid storage part 231 has a part of a wall surface constituted by a diaphragm part 232. The diaphragm portion 232 receives the pressure of the liquid in the liquid storage portion 231 on the first surface 232a serving as the inner surface of the liquid storage portion 231, while reducing the atmospheric pressure on the second surface 232b serving as the outer surface of the liquid storage portion 231. receive.

  Therefore, the diaphragm 232 is displaced in accordance with the pressure in the liquid container 231. Therefore, the volume of the liquid container 231 changes as the diaphragm 232 is displaced. The liquid inflow section 252 and the liquid storage section 231 are connected by a communication path 254.

  The pressure adjusting mechanism 250 connects the liquid inflow portion 252 and the liquid storage portion 231 with each other in a valve-closed state (a state shown in FIG. 12) in which the liquid inflow portion 252 and the liquid storage portion 231 are not communicated with each other. An on-off valve 255 capable of switching between an open state (the state shown in FIG. 13) is provided.

  The on-off valve 255 includes a valve part 256 that can shut off the communication path 254 and a rod part 257 that is inserted into the communication path 254. The rod portion 257 is in contact with a substantially disk-shaped pressure receiving portion 258 that is disposed so that the tip thereof contacts the center of the first surface 232a of the diaphragm portion 232. In this case, the pressure receiving portion 258 may be fixed to the tip of the rod portion 257, or may be fixed to the center of the first surface 232a of the diaphragm portion 232.

  The on-off valve 255 moves by being pressed by the diaphragm 232 via the pressure receiving part 258. That is, the pressure receiving portion 258 also functions as a movable member that can move in a state of being in contact with the diaphragm portion 56 that is displaced in a direction to reduce the volume of the liquid storage portion 231.

  An upstream biasing member 259 is provided in the liquid inflow section 252, and a downstream biasing member 260 is provided in the liquid storage section 231. The upstream urging member 259 urges the opening / closing valve 255 in the closing direction, and the downstream urging member 260 urges the pressure receiving portion 258 toward the diaphragm portion 232. The on-off valve 255 is configured such that the pressure applied to the first surface 232a is lower than the pressure applied to the second surface 232b, and the difference between the pressure applied to the first surface 232a and the pressure applied to the second surface 232b is a predetermined value. (For example, 1 kPa) or more, the valve changes from the closed state to the open state.

  This predetermined value is required for the urging force of the upstream urging member 259, the urging force of the downstream urging member 260, the force required to displace the diaphragm 232, and the cutoff of the communication path 254 by the valve 256. This value is determined according to the pressing force (seal load), the pressure in the liquid inflow portion 252 acting on the surface of the valve portion 256, and the pressure in the liquid storage portion 231. That is, the predetermined value increases as the urging force of the upstream urging member 259 and the downstream urging member 260 increases.

  The urging force of the upstream urging member 259 and the downstream urging member 260 is in a negative pressure state (for example, the second pressure state) in a range where the pressure in the liquid container 231 can form the meniscus 64 at the gas-liquid interface in the nozzle 19. When the pressure applied to the surface 232b is atmospheric pressure, the pressure is set to -1 kPa). In this case, the gas-liquid interface is a boundary between the liquid and the gas, and the meniscus 64 is a curved liquid surface formed by the liquid in contact with the nozzle 19. It is preferable that a concave meniscus 64 suitable for ejecting liquid is formed in the nozzle 19.

  The pressing mechanism 251 has a rotatable lever 233 having a pressing portion 237 capable of pressing the second surface 232 b side of the diaphragm portion 232, and a pressure adjusting chamber having a flexible wall 221 for applying a rotating power to the lever 233. 220 and a pressure adjusting unit 210 (see FIG. 7) capable of adjusting the pressure in the pressure adjusting chamber 220. The flexible wall 221 bulges or dents as the pressure in the pressure adjustment chamber 220 is adjusted by the pressure adjustment unit 210 (see FIG. 7).

  Then, the pressing mechanism 251 expands the flexible wall 221 by adjusting the pressure in the pressure adjusting chamber 220 to a pressure higher than the atmospheric pressure by the pressure adjusting unit 210 (see FIG. 7), thereby expanding the diaphragm 232. The opening / closing valve 255 is opened by pressing the liquid storage unit 231 in a direction in which the volume of the liquid storage unit 231 is reduced by the pressing unit 237 of the lever 233.

  That is, when the flexible wall 221 expands in a state of being in contact with the pressed portion 238 of the lever 233, the pressed portion 238 is pressed by the flexible wall 221, and a turning power is applied to the lever 233. Rotate around a fulcrum, which is a contact portion with the mounting portion 218, as a rotation center.

  With the rotation of the lever 233, the pressing portion 237 presses the second surface 232b side of the diaphragm portion 232 in a direction in which the volume of the liquid storage portion 231 decreases, so that the on-off valve 255 is opened from the closed state. State. At this time, the pressing portion 237 of the pressing mechanism 251 presses a region of the diaphragm 232 where the pressure receiving portion 258 contacts. In this case, the area of the region of the diaphragm 232 where the pressure receiving part 258 contacts is larger than the cross-sectional area of the communication path 254.

  Further, the pressing mechanism 251 is configured such that the pressure adjusting unit 210 (see FIG. 7) lowers the pressure in the pressure adjusting chamber 220 to a pressure lower than the pressure in the pressure adjusting chamber 220 when the diaphragm 232 is pressed by the pressing unit 237 of the lever 233. , The pressing of the diaphragm portion 232 by the pressing portion 237 of the lever 233 is released. Note that, in a state where the rotation power is not applied to the lever 233 by the flexible wall 221, the pressing portion 237 is separated from the diaphragm portion 232.

Next, the operation of the pressure adjusting device 200 for adjusting the pressure of the liquid supplied to the liquid ejecting unit 12 will be described.
When the liquid ejecting unit 12 ejects the liquid, the liquid accommodated in the liquid accommodating unit 231 is supplied to the liquid ejecting unit 12 via the liquid supply path 27. Then, as shown in FIG. 13, when the pressure in the liquid storage portion 231 decreases and the difference between the pressure applied to the first surface 232a and the pressure applied to the second surface 232b of the diaphragm portion 232 becomes equal to or greater than a predetermined value. The diaphragm portion 232 is bent and deformed in a direction to reduce the volume of the liquid storage portion 231. With the deformation of the diaphragm portion 232, the on-off valve 255 is pressed and moved via the pressure receiving portion 258, and the on-off valve 255 is opened.

  Then, since the liquid in the liquid inflow section 252 is pressurized by the pressurizing mechanism 31, the liquid is supplied from the liquid inflow section 252 to the liquid storage section 231 and the pressure in the liquid storage section 231 increases. As a result, the diaphragm 232 is deformed so as to increase the volume of the liquid container 231. When the difference between the pressure applied to the first surface 232a and the pressure applied to the second surface 232b of the diaphragm 232 becomes smaller than a predetermined value, the on-off valve 255 moves by the urging force of the upstream urging member 259. As a result, the valve is changed from the open state to the closed state, and the flow of the liquid is inhibited.

  In this way, the pressure adjusting mechanism 250 adjusts the pressure of the liquid supplied to the liquid ejecting unit 12 by displacing the diaphragm unit 232, thereby reducing the pressure in the liquid ejecting unit 12 that becomes the back pressure of the nozzle 19. adjust.

Next, a description will be given of the operation in the case where the cleaning is performed by forcibly flowing the liquid from the liquid supply source 13 to the liquid ejecting unit 12 for the maintenance of the liquid ejecting unit 12.
As shown in FIG. 11, the control unit 78 (see FIG. 4) closes the first valve V1 and the third valve V3 of the pressure adjusting unit 210 and opens the second valve V2 and the fourth valve V4. When the pump 241 is driven, air is supplied under pressure from the pressure connection part 211, and the pressure in the pressure adjustment chamber 220 (see FIG. 12) is adjusted to a pressure higher than the atmospheric pressure.

  As a result, as shown in FIG. 13, the flexible wall 221 expands and presses the pressed portion 238 of the lever 233, and the lever 233 is a contact portion with the mounting portion 218 against the urging force of the torsion spring 235. It rotates around the fulcrum.

  Then, the pressing portion 237 of the lever 233 presses the area of the diaphragm 232 where the pressure receiving portion 258 contacts, against the urging force of the downstream urging member 260. Then, the on-off valve 255 also receives the pressing force of the pressing portion 237 via the diaphragm 232 and the pressure receiving portion 258 and moves against the urging force of the upstream urging member 259, and the on-off valve 255 is opened.

  That is, the pressing mechanism 251 opens the on-off valve 255 by moving the pressure receiving portion 258 and the on-off valve 255 against the urging force of the upstream urging member 259 and the downstream urging member 260. That is, the control unit 78 causes the pressing mechanism 251 to press the diaphragm 232 to open the on-off valve 255. In this case, since the pressure adjustment units 210 are connected to the pressure connection units 211 of the plurality of pressure adjustment devices 200, the on-off valves 255 of all the pressure adjustment devices 200 are opened.

  At this time, since the diaphragm 232 is deformed in a direction to reduce the volume of the liquid container 231, the liquid stored in the liquid container 231 is pushed out to the liquid ejecting unit 12 side. In other words, the pressure at which the diaphragm 232 presses the liquid container 231 is transmitted to the liquid ejecting unit 12, so that the meniscus 64 is broken and the liquid overflows from the nozzle 19.

  That is, the pressing mechanism 251 sets the pressure in the liquid container 231 higher than the pressure at which at least one meniscus 64 is broken (for example, the pressure at which the liquid pressure at the gas-liquid interface becomes 3 kPa higher than the gas pressure). The diaphragm part 232 is pressed so as to make it.

  Further, the pressing mechanism 251 opens the on-off valve 255 by pressing the diaphragm 232 regardless of the pressure in the liquid inflow portion 252. In this case, the pressing mechanism 251 presses the diaphragm 232 with a pressing force greater than a pressing force generated when a pressure obtained by adding the above-described predetermined value to the pressure at which the pressing mechanism 31 presses the liquid is applied to the diaphragm 232. Press.

  Then, in a state where the on-off valve 255 is opened by the pressing mechanism 251 pressing the diaphragm 232 by the pressing mechanism 251, the control unit 78 periodically drives the depressurizing unit 43, so that the pressurizing unit 31 pressurizes the part. A fixed amount of liquid is supplied to the liquid ejecting unit 12. That is, when the pressure in the negative pressure chamber 42 is reduced by driving the pressure reducing unit 43, the flexible member 37 moves in a direction to increase the volume of the pump chamber 41.

  Then, the liquid flows into the pump chamber 41 from the liquid supply source 13. When the decompression by the decompression unit 43 is released, the flexible member 37 is urged by the urging force of the urging member 44 in a direction to reduce the volume of the pump chamber 41. That is, a predetermined amount of liquid in the pump chamber 41 is pressurized by the urging force of the urging member 44 via the flexible member 37, passes through the one-way valve 40 on the downstream side, and flows downstream of the liquid supply path 27. Side to be supplied to the liquid ejecting unit 12.

  Since the open / close valve 255 is kept open while the pressing mechanism 251 is pressing the diaphragm 232, when the pressing mechanism 31 presses a predetermined amount of liquid in this state, the pressing force increases the liquid inflow. Pressure cleaning is performed in which the liquid is discharged (dropped) from the nozzle 19 through the unit 252, the communication path 254, and the liquid storage unit 231 to the liquid ejecting unit 12. That is, the control unit 78 supplies a predetermined amount of liquid in a pressurized state to the liquid ejecting unit 12 by causing the pressurizing mechanism 31 to pressurize the liquid, and discharges the liquid from the nozzle 19.

  When a predetermined amount of liquid (a predetermined amount of liquid in the pump chamber 41) is discharged from the nozzle 19, the discharge of the liquid from the nozzle 19 is stopped. That is, when the pressurizing mechanism 31 discharges (drops) a predetermined amount of pressurized liquid from the nozzle 19, the level of pressurization of the supplied liquid decreases with the discharge of the liquid, and the pressurizing mechanism 31 The pressure level is such that no liquid is discharged.

  In this state, the control unit 78 drives the wiping motor 131 to cause the wiping member 130 to wipe the nozzle forming surface 18. As a result, the meniscus 64 is formed in the nozzle 19 at an internal pressure higher than the internal pressure of the liquid ejecting unit 12 at the time of normal meniscus formation. Thereafter, when the control unit 78 opens the first valve V1 and the third valve V3 of the pressure adjustment unit 210 and closes the second valve V2 and the fourth valve V4, air is sucked from the pressure connection unit 211 and the pressure is reduced. The pressure in the adjustment chamber 220 is reduced.

  As a result, the bulging flexible wall 221 is deflated and dented. Then, the lever 233 is rotated by the biasing force of the torsion spring 235 about the fulcrum, which is a contact portion with the mounting portion 218, and returns to the original position. That is, the pressing portion 237 of the lever 233 is separated from the diaphragm 232.

  Then, the diaphragm portion 232 and the pressure receiving portion 258 return to the original position by the urging force of the downstream urging member 260, and the on-off valve 255 moves by the urging force of the upstream urging member 259 to be in a closed state. That is, the control unit 78 closes the on-off valve 255 by releasing the pressing state of the diaphragm unit 232 by the pressing mechanism 251 in a state where the liquid is pressurized by the pressing mechanism 31 to such an extent that the liquid is not discharged from the nozzle 19. State.

  At this time, when the internal pressure of the liquid ejecting unit 12 is reduced by the closing operation of the on-off valve 255, the meniscus 64 in the nozzle 19 may be broken and air or the like may be drawn into the nozzle 19. In this regard, in the present embodiment, as described above, the meniscus 64 is formed in the nozzle 19 at an internal pressure higher than the internal pressure of the liquid ejecting unit 12 at the time of normal meniscus formation. Even if the internal pressure of the liquid ejecting unit 12 is reduced, it is possible to prevent the meniscus 64 from breaking and drawing air or the like into the nozzle 19. Thus, the pressure cleaning of the liquid ejecting unit 12 is completed, and then the control unit 78 stops the pump 241 of the pressure adjusting unit 210.

As described above, according to the second embodiment, the following effects can be obtained.
(12) In the liquid ejecting apparatus 11, the pressing mechanism 251 rotates the lever 233 by the pressure adjusting unit 210 adjusting the pressure in the pressure adjusting chamber 220 to apply the rotating power to the lever 233 by the flexible wall 221. Then, the pressing portion 237 presses the second surface 232 b side of the diaphragm portion 232. Therefore, the pressing force by the pressing portion 237 can be changed only by changing the specifications (lever ratio, shape, etc.) of the lever 233 without changing the specifications (pressure, size, etc.) of the pressure adjustment chamber 220. it can. That is, even if the necessary pressing force of the pressing portion 237 changes, it is possible to cope with the change of the specification of the lever 233 without changing the specification of the pressure adjusting chamber 220. it can.

  (13) In the liquid ejecting apparatus 11, the pressing portion 237 is separated from the diaphragm portion 232 in a state where the rotating power is not applied to the lever 233 by the flexible wall 221. For this reason, it is possible to suppress the occurrence of operation failure of the pressure adjustment mechanism 250 caused by the contact of the pressing portion 237 of the lever 233 with the diaphragm portion 232.

  (14) In the liquid ejecting apparatus 11, the pressing mechanism 251 presses the area of the diaphragm 232 where the pressure receiving part 258 contacts with the pressing part 237 of the lever 233. Therefore, the diaphragm portion 232 can be pressed by the pressing portion 237 so as not to deform the outer region (peripheral region) of the pressure receiving portion 258 in the diaphragm portion 232 toward the liquid storage portion 231. Then, after the pressing of the diaphragm portion 232 by the pressing portion 237 is released, the outer region of the pressure receiving portion 258 in the diaphragm portion 232 moves in the direction in which the volume of the liquid storage portion 231 increases, and returns to the state before the pressing. In addition, it is possible to prevent bubbles and liquid from being drawn from the nozzle 19.

  (15) In the liquid ejecting apparatus 11, the pressing mechanism 251 adjusts the pressure in the pressure adjusting chamber 220 to a pressure higher than the atmospheric pressure by the pressure adjusting unit 210, and thereby the diaphragm 232 is pressed by the pressing unit 237 of the lever 233. Press. Therefore, the diaphragm portion 232 can be pressed by the pressing portion 237 of the lever 233 only by adjusting the pressure in the pressure adjustment chamber 220 to a pressure higher than the atmospheric pressure.

  (16) In the liquid ejecting apparatus 11, the pressing mechanism 251 causes the pressure adjusting unit 210 to reduce the pressure in the pressure adjusting chamber 220 to a pressure lower than the pressure in the pressure adjusting chamber 220 when the diaphragm 232 is pressed by the pressing unit 237. By adjusting, the pressing of the diaphragm portion 232 by the pressing portion 237 of the lever 233 is released. Therefore, the pressing state of the diaphragm portion 232 by the pressing portion 237 of the lever 233 can be easily released.

  (17) In the liquid ejecting apparatus 11, the turning power applying unit is the flexible wall 221 that forms a part of the pressure adjustment chamber 220, and applies the turning power to the lever 233 by coming into contact with the lever 233. For this reason, the flexible wall 221 that forms a part of the pressure adjustment chamber 220 can suitably function as a turning power applying unit that applies turning power to the lever 233.

  (18) In the liquid ejecting apparatus 11, the pressurizing mechanism 31 pressurizes the liquid in the open state of the on-off valve 255 by the pressing mechanism 251 pressing the diaphragm 232, thereby ejecting the liquid in the pressurized state. Supply to the unit 12. For this reason, cleaning in which the liquid in the pressurized state is supplied to the liquid ejecting unit 12 and discharged from the nozzle 19 by pressurizing the liquid by the pressurizing mechanism 31 in a state where the on-off valve 255 is forcibly opened, that is, so-called cleaning. Pressure cleaning can be performed.

  (19) In a state where the liquid is pressurized by the pressurizing mechanism 31, the liquid ejecting apparatus 11 releases the pressing state of the diaphragm 232 by the pressing mechanism 251 and closes the on-off valve 255. Therefore, it is possible to suppress bubbles and liquid from being drawn in from the nozzle 19 after the pressure cleaning.

  (20) In the liquid ejecting apparatus 11, the control unit 78 opens the on-off valve 255 by pressing the diaphragm unit 232 by the pressing mechanism 251 and pressurizes the liquid by the pressing mechanism 31 by pressing the liquid. After the liquid is supplied to the liquid ejecting unit 12 and discharged from the nozzle 19, the wiping member 130 wipes the nozzle forming surface 18. For this reason, after performing the pressure cleaning in which the liquid pressurized by the pressing mechanism 31 is supplied to the liquid ejecting unit 12 and forcibly discharged from the nozzle 19, the wiping member 130 wipes the nozzle forming surface 18 (wiping). ), A meniscus 64 can be formed in the nozzle 19. Therefore, after the pressure cleaning is performed, it is possible to suppress the liquid attached to the vicinity of the nozzle opening on the nozzle forming surface 18 from being sucked into the nozzle 19 together with the foreign matter and bubbles.

  (21) In the liquid ejecting apparatus 11, the control section 78 supplies the liquid ejecting section 12 with a predetermined amount of liquid in a pressurized state by causing the pressurizing mechanism 31 to pressurize a predetermined amount of liquid. After the discharge of the liquid is stopped, the wiping member 130 wipes the nozzle forming surface 18, and then the pressing mechanism 251 releases the pressing state of the diaphragm 232 to close the on-off valve 255.

  Normally, when a predetermined amount of pressurized liquid is discharged from the nozzle 19, the level of pressurization of the supplied liquid decreases with the discharge of the liquid, and the pressurization level is such that the liquid is not discharged from the nozzle 19 soon. become. By wiping (wiping) the nozzle forming surface 18 by the wiping member 130 in this state, the meniscus 64 can be formed in the nozzle 19 at an internal pressure higher than the internal pressure of the liquid ejecting unit 12 during normal meniscus formation. . For this reason, when the internal pressure of the liquid ejecting unit 12 decreases due to the valve closing operation of the on-off valve 255, it is possible to prevent the meniscus 64 in the nozzle 19 from breaking and drawing air or the like into the nozzle 19.

(Example of change)
The above embodiments may be modified as follows.
(Modification 1) The pressure cleaning for maintenance of the liquid ejecting unit 12 in the second embodiment may be performed as follows. That is, first, the control unit 78 causes the pressing mechanism 251 to press the diaphragm unit 232 to open the on-off valve 255, and then supplies the liquid to a pressurizing pump (pressurizing mechanism) that can continuously pressurize the liquid. By applying pressure, the liquid in a pressurized state is supplied to the liquid ejecting unit 12 and discharged from the nozzle 19. Then, the control unit 78 closes the on-off valve 255 by causing the pressing mechanism 251 to release the pressing state of the diaphragm unit 232 to stop the supply of the liquid in the pressurized state to the liquid ejecting unit 12, and then the wiping member. 130 causes the nozzle forming surface 18 to be wiped. Thus, the pressure cleaning is completed. With this configuration, if the on-off valve 255 is closed while the pressurized liquid is being discharged from the nozzle 19, the liquid in the pressurized state of the liquid ejecting unit 12 is discharged from the nozzle 19 even after the on-off valve 255 is closed. The liquid is discharged and has a pressurized level at which the liquid is not discharged from the nozzle 19 soon. By wiping (wiping) the nozzle forming surface 18 by the wiping member 130 in this state, the meniscus 64 can be formed in the nozzle 19 at an internal pressure higher than the internal pressure of the liquid ejecting unit 12 during normal meniscus formation. . For this reason, when the internal pressure of the liquid ejecting unit 12 decreases due to the valve closing operation of the on-off valve 255, it is possible to prevent the meniscus 64 in the nozzle 19 from breaking and drawing air or the like into the nozzle 19.

  (Modification 2) In Modification 1, as shown in FIG. 14, the control unit 78 caps the cap 134 on a region including the nozzle 19 on the nozzle forming surface 18 of the liquid ejecting unit 12. When the liquid is pressurized by the pressurizing mechanism, the liquid in a pressurized state is supplied to the liquid ejecting unit 12 and discharged from the nozzle 19. Then, after closing the on-off valve 255 to stop the discharge of the liquid from the nozzle 19, the control unit 78 releases the capping state of the area by the cap 134, and then attaches the nozzle forming surface 18 to the wiping member 130. You may make it wipe. With this configuration, when the liquid is discharged from the nozzle 19 in a state where the area including the nozzle 19 on the nozzle forming surface 18 of the liquid ejecting unit 12 is capped by the cap 134, the pressure in the cap 134 increases and the atmospheric pressure is increased. Therefore, a resistance is generated which prevents the liquid from being discharged from the nozzle 19. Therefore, the pressure level when the liquid is no longer discharged from the nozzle 19 is higher than when no capping is performed. Even if the capping state by the cap 134 is released in this state, it is difficult for air or the like to be drawn into the nozzle 19. Thereafter, by wiping (wiping) the nozzle forming surface 18 by the wiping member 130, the meniscus 64 can be formed in the nozzle 19 at an internal pressure higher than the internal pressure of the liquid ejecting unit 12 during normal meniscus formation. Therefore, when the internal pressure of the liquid ejecting unit 12 decreases due to the valve closing operation of the on-off valve 255, it is possible to prevent the meniscus 64 in the nozzle 19 from breaking and drawing air or the like into the nozzle 19.

  (Modification 3) In Modification 2, as shown in FIG. 15, a discharge channel 301 for discharging the liquid in the cap 134 to the box-shaped waste liquid collecting container 300 is provided on the bottom wall of the cap 134. It may be. With this configuration, when the liquid is discharged from the nozzle 19 in a state where the area including the nozzle 19 on the nozzle forming surface 18 of the liquid ejecting unit 12 is capped by the cap 134, the flow when the liquid flows through the discharge flow path 301 Due to the influence of the road resistance, the pressure in the cap 134 rises and becomes higher than the atmospheric pressure, as in the case of the second modification. For this reason, it is possible to obtain the same operation and effect as the above-described second modification.

  (Modification 4) In Modification 2, as shown in FIG. 16, the cap 134 is formed on the bottom wall of the cap 134 when the region including the nozzle 19 on the nozzle forming surface 18 of the liquid ejecting unit 12 is capped. A communication channel 302 for communicating a closed space with the atmosphere is provided. Further, an air release valve 303 that can be switched between a communicating state in which the closed space communicates with the atmosphere and a non-communicating state in which the closed space does not communicate with the atmosphere may be provided at an intermediate position of the communication channel 302. Then, the control unit 78 may switch the air release valve 303 from the communication state to the non-communication state during a certain time during the discharge of the liquid from the nozzle 19 and at the time of releasing the capping state of the area by the cap 134. In this way, the liquid is discharged from the nozzle 19 while the air release valve 303 is in communication and the area including the nozzle 19 on the nozzle forming surface 18 of the liquid ejecting unit 12 is capped by the cap 134, and the air is released to the atmosphere from the middle. By switching the valve 303 to the non-communication state, the pressure in the cap 134 can be changed. That is, by changing the timing of switching the atmosphere release valve 303 from the communicating state to the non-communicating state, the degree of increase in the pressure in the cap 134 can be adjusted. Incidentally, since the pressure in the cap 134 changes depending on the amount of liquid discharged, for example, when the volume of the cap 134 is small and the amount of liquid discharged into the cap 134 is large, the communication state of the atmosphere release valve 303 is changed. If the timing of switching to the non-communication state is too early, the pressure in the cap 134 becomes too large. Therefore, the liquid may not be discharged from the nozzle 19 into the cap 134.

  (Modification 5) In the second embodiment, as shown in FIG. 16, a discharge flow path 304 for discharging the liquid in the cap 134 is provided on the bottom wall of the cap 134, and the discharge flow path 304 is located at an intermediate position. Is provided with a suction pump 305 capable of sucking the inside of the cap 134. Then, after performing the suction cleaning for discharging the liquid from the nozzle 19 by the suction force of the suction pump 305, the pressure cleaning of the fourth modification may be performed in combination.

  (Modification 6) In the second embodiment, as shown in FIG. 17, the pressure adjusting chamber and the turning power applying unit in the pressing mechanism 251 are configured to expand and contract due to the internal pressure being adjusted by the pressure adjusting unit 210. It may be constituted by an elastic member 306 having a portion. In FIG. 17, the extended state of the elastic member 306 is indicated by a solid line, and the contracted state is indicated by a two-dot chain line. Alternatively, the pressure adjusting chamber and the turning power applying unit in the pressing mechanism 251 may be configured by an air cylinder.

  (Modification 7) In the second embodiment, the pressing portion 237 of the lever 233, the rotation center of the lever 233, and the pressed portion 238 of the lever 233 are, for example, the rotation center of the lever 233 and the pressing portion of the lever 233. 237 and the pressed portion 238 of the lever 233 may be arranged in this order. In this case, the pressure adjustment chamber 220 and the flexible wall 221 are arranged on the same side as the above-described second embodiment, and when the pressure adjustment chamber 220 is depressurized, the lever 233 is rotated, and the diaphragm 232 is pressed by the pressing part 237. Pressed. Further, in this case, the pressed portion 238 and the flexible wall 221 need to be connected to each other.

(Modification 8) In the second embodiment, the turning power applying unit does not necessarily need to be the flexible wall 221.
(Modification 9) In the second embodiment, the pressure receiving portion 258 may be omitted.

  (Modification 10) In the above-described second embodiment, in a state where the rotating power is not applied to the lever 233 by the flexible wall 221, the pressing portion 237 does not necessarily have to be separated from the diaphragm 232.

(Modification 11) In the second embodiment, a pressure receiving portion may be provided on the flexible wall 221.
(Modification 12) In the second embodiment, the lever 233 may be made of metal, and the lever 233 may press the diaphragm 232 using the elasticity of the metal. By doing so, the torsion spring 235 can be omitted.

(Modification 13) In the second embodiment, the on-off valve 255 and the pressure receiving portion 258 may be connected to each other or may be formed integrally.
(Modification 14) In the second embodiment, the pressurizing mechanism 31 may be constituted by a gear pump, a screw pump, a piston pump, or the like.

  (Modification 15) In each of the above embodiments, the liquid ejecting apparatus 11 may be a liquid ejecting apparatus that ejects or discharges liquid other than ink. Note that the state of the liquid ejected as a minute amount of liquid droplets from the liquid ejecting apparatus includes a state in which the liquid ejects a tail in a granular shape, a tear shape, or a thread shape. Further, the liquid referred to here may be any material that can be ejected from the liquid ejecting apparatus. For example, the substance may be in the state of being in a liquid phase, and may be a liquid substance having high or low viscosity, sol, gel water, other inorganic solvent, organic solvent, solution, liquid resin, liquid metal (metal melt). )). In addition, not only a liquid as one state of a substance but also a substance in which particles of a functional material formed of a solid such as a pigment or metal particles are dissolved, dispersed, or mixed in a solvent is included. Representative examples of the liquid include various liquid compositions such as aqueous inks, non-aqueous inks, oil-based inks, gel inks, hot-melt inks, and liquid crystals described in the above embodiments. As a specific example of the liquid ejecting apparatus, for example, a liquid containing materials such as an electrode material and a coloring material used in the manufacture of a liquid crystal display, an EL (electroluminescence) display, a surface-emitting display, a color filter, and the like in a dispersed or dissolved form. There is a liquid ejecting apparatus that ejects liquid. Further, a liquid ejecting apparatus for ejecting a biological organic substance used for manufacturing a biochip, a liquid ejecting apparatus used as a precision pipette for ejecting a liquid serving as a sample, a printing apparatus, a microdispenser, or the like may be used. Further, a transparent resin liquid such as an ultraviolet curable resin is used to form a liquid ejecting device that injects a lubricating oil into a precision machine such as a watch or a camera in a pinpoint manner, and a micro hemispherical lens (optical lens) used for an optical communication element. May be a liquid ejecting apparatus that ejects the liquid onto the substrate. Further, a liquid ejecting apparatus which ejects an etching solution such as an acid or an alkali for etching a substrate or the like may be used.

  DESCRIPTION OF SYMBOLS 11 ... Liquid ejection apparatus, 12 ... Liquid ejection part, 13 ... Liquid supply source, 14 ... Supply mechanism, 16 ... Injection part filter, 17 ... Common liquid chamber, 18 ... Nozzle formation surface, 19 ... Nozzle, 20 ... Pressure chamber, DESCRIPTION OF SYMBOLS 21 ... diaphragm, 22 ... communication hole, 23 ... accommodation chamber, 24 ... actuator, 26 ... mounting part, 27 ... liquid supply path, 28 ... circulation path forming part, 29 ... circulation pump, 31 ... pressurizing mechanism, 32 ... Filter unit, 33 static mixer, 34 liquid storage unit, 35 pressure adjustment mechanism, 37 flexible member, 38 volumetric pump, 39 one-way valve, 40 one-way valve, 41 pump chamber, 42 .., Negative pressure chamber, 43, pressure reducing section, 44, urging member, 45, spring, 47, pressure adjusting device, 48, pressing mechanism, 50, liquid inflow section, 51, liquid storage section, 52, main body section, 53 Wall part, 54 ... through-hole, 55 ... Filter member, 56 diaphragm part, 56a first surface, 56b second surface, 57 communication path, 59 opening / closing valve, 60 valve part, 61 pressure receiving part, 62 upstream biasing member, 63 ... downstream side urging member, 64 ... meniscus, 66 ... pressure adjustment chamber, 67 ... expansion and contraction part, 68 ... holding member, 69 ... pressure adjustment part, 70 ... insertion hole, 71 ... opening, 72 ... air chamber, 74 ... Pressure pump, 75 ... Connection path, 76 ... Detection unit, 77 ... Fluid pressure adjustment unit, 78 ... Control unit, 112 ... Support table, 113 ... Medium, 114 ... Conveyance unit, 115 ... Printing unit, 116 ... Main unit 117: cover, 118: transport roller pair, 119: transport roller pair, 120: guide plate, 122: guide shaft, 123: guide shaft, 124: carriage, 126: wiper unit, 127: flushing unit, 128: cap 130, a wiping member, 131, a wiping motor, 132, a liquid receiving portion, 133, a flushing motor, 134, a cap, 135, a capping motor, 200, a pressure adjusting device, 201, an air chamber forming unit, 202, a pressure adjusting mechanism. Forming unit, 203: bottom plate member, 204: connecting unit forming unit, 205: lever unit, 206: main body, 207: connecting film, 208: first liquid connecting unit, 209: second liquid connecting unit, 210: pressure adjustment Part, 211: pressure connection part, 212, first liquid outlet part, 213, second liquid outlet part, 214, pressure supply part, 215, main body part, 216, air chamber film, 217, air introduction part, 218, mounting Part, 219 ... concave part, 220 ... pressure adjustment chamber, 221 ... flexible wall (rotational power applying part), 222 ... groove, 2 23 ... through-hole, 224 ... through-hole, 225 ... air passage, 226 ... main body part, 227 ... pressure film, 228 ... first liquid introduction part, 229 ... second liquid introduction part, 230 ... concave part, 231 ... liquid storage Part, 232 ... diaphragm part, 232a ... first surface, 232b ... second surface, 233 ... lever, 234 ... locking part, 235 ... torsion spring, 236 ... mounting hole, 237 ... pressing part, 238 ... pressed Part, 240 ... annular pipe, 241 ... pump, 242 ... connecting pipe, 243 ... first branch pipe, 244 ... second branch pipe, 247 ... wall part, 248 ... through hole, 249 ... filter member, 250 ... pressure adjusting mechanism , 251: Pressing mechanism, 252: Liquid inflow section, 254: Communication path, 255: Open / close valve, 256: Valve section, 257: Rod section, 258: Pressure receiving section (moving member), 259: Upstream biasing member, 260 …downstream Urging member, 300: waste liquid collecting container, 301: discharge channel, 302: communication channel, 303: atmosphere release valve, 304: discharge channel, 305: suction pump, 306: telescopic member, A: supply direction, B ... circulation direction, X ... scanning direction, Y ... transport direction, Z ... vertical direction, V1 ... first valve, V2 ... second valve, V3 ... third valve, V4 ... fourth valve.

Claims (7)

A liquid supply path capable of supplying the liquid from a liquid supply source to a liquid ejecting unit that ejects liquid from a nozzle by driving an actuator,
A pressure adjusting mechanism provided in the liquid supply path,
A liquid inflow portion into which the liquid supplied from the liquid supply source flows,
A liquid storage portion capable of storing the liquid therein and having an internal volume that changes due to displacement of a diaphragm portion,
A communication path for communicating the liquid inflow section and the liquid storage section,
The pressure applied to the first surface of the diaphragm portion that is the inner surface of the liquid storage portion is lower than the pressure applied to the second surface of the diaphragm portion that is the outer surface of the liquid storage portion, and the pressure applied to the first surface. When the difference between the pressure and the pressure applied to the second surface becomes equal to or greater than a predetermined value, the liquid inflow portion and the liquid storage portion are changed from the valve-closed state in which the liquid inflow portion and the liquid storage portion are not communicated in the communication path. A pressure regulating mechanism having an on-off valve that is in an open state to communicate with the section,
By pressing the diaphragm portion in a direction in which the volume of the liquid storage portion decreases, a pressing mechanism that opens the on-off valve,
A pressurizing mechanism capable of pressurizing the liquid supplied to the pressure adjusting mechanism by a predetermined amount ,
A wiping member capable of wiping a nozzle forming surface on which the nozzle is formed in the liquid ejecting unit,
The predetermined amount of the liquid in a pressurized state is supplied to the liquid ejecting unit by pressing the liquid by the pressing mechanism by opening the on-off valve by pressing the diaphragm unit by the pressing mechanism and pressing the liquid by the pressing mechanism. And a controller configured to cause the wiping member to wipe the nozzle forming surface after discharging from the nozzle. Prior Symbol controller, the liquid of the predetermined amount before Symbol pressurized and supplied to the liquid ejecting portion after the discharge of the liquid from the nozzle is stopped, wiping the nozzle formation surface in the wiping member 2. The liquid ejecting apparatus according to claim 1, wherein the on-off valve is closed by causing the pressing mechanism to release the pressing state of the diaphragm portion. Wherein, prior Symbol the liquid of the predetermined amount of pressurized and supplied to the liquid ejecting portion is discharged from the nozzle, the on-off valve by releasing the pressing state of the diaphragm portion to the pressing mechanism 2. The liquid ejecting apparatus according to claim 1, wherein the valve is closed to stop supplying the pressurized liquid to the liquid ejecting unit, and then the wiping member wipes the nozzle forming surface. 3. A liquid supply path that can supply the liquid from a liquid supply source to a liquid ejecting unit that ejects liquid from a nozzle,
A pressure adjusting mechanism provided in the liquid supply path,
A liquid inflow portion into which the liquid supplied from the liquid supply source flows,
A liquid storage portion capable of storing the liquid therein and having an internal volume that changes due to displacement of a diaphragm portion,
A communication path for communicating the liquid inflow section and the liquid storage section,
The pressure applied to the first surface of the diaphragm portion that is the inner surface of the liquid storage portion is lower than the pressure applied to the second surface of the diaphragm portion that is the outer surface of the liquid storage portion, and the pressure applied to the first surface. When the difference between the pressure and the pressure applied to the second surface becomes equal to or greater than a predetermined value, the liquid inflow portion and the liquid storage portion are changed from the valve-closed state in which the liquid inflow portion and the liquid storage portion are not communicated in the communication path. A pressure regulating mechanism having an on-off valve that is in an open state to communicate with the section,
By pressing the diaphragm portion in a direction in which the volume of the liquid storage portion decreases, a pressing mechanism that opens the on-off valve,
A pressure mechanism capable of pressurizing the liquid supplied to the pressure adjustment mechanism,
A wiping member capable of wiping a nozzle forming surface on which the nozzle is formed in the liquid ejecting unit,
A cap capable of forming a closed space including the nozzle by capping a region including the nozzle of the liquid ejecting unit ,
The on-off valve is opened by the pressing mechanism, and the liquid is pressurized by the pressurizing mechanism to supply the liquid in a pressurized state to the liquid ejecting unit in a state where the cap is capped in the area. and is discharged from the nozzle, the pressure of the closed space releases the capping state of the area by previous SL cap higher than atmospheric pressure, and a control unit for wiping the nozzle formation surface in the wiping member liquids ejection device you wherein a. Said cap, between the closed space formed upon capping the region having the air release valve capable of switching between a non-communicated state which is not communicating with the communication with the atmosphere communication with the atmosphere,
Wherein, in the middle the discharge of the liquid from the nozzle of the and the cap air opening valve is in the communication state is in the capping state, to switch the air release valve from the communicating state to the non-communicated state The liquid ejecting apparatus according to claim 4, wherein: A liquid supply path capable of supplying the liquid from a liquid supply source to a liquid ejecting unit that ejects liquid from a nozzle by driving an actuator,
A pressure adjusting mechanism provided in the liquid supply path,
A liquid inflow portion into which the liquid supplied from the liquid supply source flows,
A liquid storage portion capable of storing the liquid therein and having an internal volume that changes due to displacement of a diaphragm portion,
A communication path for communicating the liquid inflow section and the liquid storage section,
The pressure applied to the first surface of the diaphragm portion that is the inner surface of the liquid storage portion is lower than the pressure applied to the second surface of the diaphragm portion that is the outer surface of the liquid storage portion, and the pressure applied to the first surface. When the difference between the pressure and the pressure applied to the second surface becomes equal to or greater than a predetermined value, the liquid inflow portion and the liquid storage portion are changed from the valve-closed state in which the liquid inflow portion and the liquid storage portion are not communicated in the communication path. A pressure regulating mechanism having an on-off valve that is in an open state to communicate with the section,
By pressing the diaphragm portion in a direction in which the volume of the liquid storage portion decreases, a pressing mechanism that opens the on-off valve,
A pressurizing mechanism capable of pressurizing the liquid supplied to the pressure adjusting mechanism by a predetermined amount ,
A wiping member capable of wiping a nozzle forming surface on which the nozzles are formed in the liquid ejecting unit, and a maintenance method for the liquid ejecting apparatus,
The opening / closing valve was opened by pressing the diaphragm unit by the pressing mechanism, and the predetermined amount of the liquid pressurized by the pressing mechanism was supplied to the liquid ejecting unit and discharged from the nozzle. After that, the nozzle forming surface is wiped by the wiping member. A liquid supply path that can supply the liquid from a liquid supply source to a liquid ejecting unit that ejects liquid from a nozzle,
A pressure adjusting mechanism provided in the liquid supply path,
A liquid inflow portion into which the liquid supplied from the liquid supply source flows,
A liquid storage portion capable of storing the liquid therein and having an internal volume that changes due to displacement of a diaphragm portion,
A communication path for communicating the liquid inflow section and the liquid storage section,
The pressure applied to the first surface of the diaphragm portion that is the inner surface of the liquid storage portion is lower than the pressure applied to the second surface of the diaphragm portion that is the outer surface of the liquid storage portion, and the pressure applied to the first surface. When the difference between the pressure and the pressure applied to the second surface becomes equal to or greater than a predetermined value, the liquid inflow portion and the liquid storage portion are changed from the valve-closed state in which the liquid inflow portion and the liquid storage portion are not communicated in the communication path. A pressure regulating mechanism having an on-off valve that is in an open state to communicate with the section,
By pressing the diaphragm portion in a direction in which the volume of the liquid storage portion decreases, a pressing mechanism that opens the on-off valve,
A pressure mechanism capable of pressurizing the liquid supplied to the pressure adjustment mechanism,
A wiping member capable of wiping a nozzle forming surface of the liquid ejecting unit where the nozzle is formed , and a cap capable of forming a closed space including the nozzle by capping a region including the nozzle of the liquid ejecting unit. A method for maintaining a liquid ejecting apparatus, comprising:
The on-off valve is opened by the pressing mechanism, the liquid pressurized by the pressurizing mechanism is supplied to the liquid ejecting unit in a state where the area is capped by the cap, discharged from the nozzle, and closed. A maintenance method for the liquid ejecting apparatus, wherein the capping state of the area is released in a state where the pressure of the space is higher than the atmospheric pressure, and the nozzle forming surface is wiped by the wiping member.

Images