JP5691218B2 - Liquid ejecting apparatus and liquid ejecting head - Google Patents

Description

  The present invention relates to a liquid ejecting apparatus such as an ink jet printer, and a liquid ejecting head, and in particular, a liquid ejecting apparatus capable of more effectively suppressing volatilization of a liquid solvent from a nozzle, and The present invention relates to a liquid ejecting head.

  The liquid ejecting apparatus is an apparatus that includes a liquid ejecting head capable of ejecting liquid and ejects liquid from the liquid ejecting head to land on a landing target. As a typical example of this liquid ejecting apparatus, for example, an ink jet recording head (a type of liquid ejecting head; hereinafter simply referred to as a recording head) is provided, and liquid ink is ejected from nozzles of the recording head to perform recording. An image recording apparatus such as an ink jet printer (hereinafter simply referred to as a printer) that records an image, text, or the like by landing on a recording medium (a kind of landing target) such as a printing surface of paper or an optical disk can be given. . In recent years, the ink jet technology of the liquid ejecting apparatus is applied not only to the image recording apparatus but also to various manufacturing apparatuses such as a manufacturing apparatus for a color filter such as a liquid crystal display and an electrode forming apparatus.

  In such a liquid ejecting apparatus, the nozzle is exposed to the atmosphere during the printing operation. For this reason, the liquid solvent component volatilizes through the nozzle. As a result, the viscosity of the liquid increases in the vicinity of the nozzle, which may cause problems such as a decrease in the weight of the ejected ink and a decrease in the flying speed of the ink. Various measures are taken in the liquid ejecting apparatus in order to suppress such problems caused by the thickening of the liquid. For example, taking the above ink jet printer as an example, a cleaning liquid tank and a pump are connected to a cap member that seals the surface of the recording head where the nozzles are opened (hereinafter referred to as a nozzle opening surface), and the cleaning liquid is contained in the cap member. Ink solvent in the vicinity of the nozzles can be supplied and discharged by maintaining the inside of the cap member at a high humidity by holding the cleaning liquid in the cap member after cleaning the nozzles of the recording head during the non-recording operation. The structure which suppresses volatilization of this is proposed (refer patent document 1).

JP 2004-209897 A

  However, in the above-described configuration, the nozzle opening surface is released from the cap member during the recording process (during the ejection process) on the recording medium, and thus it has not been possible to reliably prevent ink thickening.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a liquid ejecting apparatus and a liquid ejecting head that can more effectively suppress the volatilization of a liquid solvent from a nozzle. It is to provide.

The present invention has been proposed to achieve the above object, and has a nozzle opening surface provided with a nozzle row composed of a plurality of opened nozzles, and a liquid is provided in a pressure chamber communicating with the nozzles. A liquid ejecting apparatus including a liquid ejecting head capable of ejecting liquid droplets from the nozzle by applying a pressure fluctuation to the liquid in the pressure chamber,
A humidifying liquid supply means for supplying the humidifying liquid to the nozzle opening surface side;
A groove portion for supplying the humidifying liquid from the humidifying liquid supply means is formed at a position off the nozzle opening on the nozzle opening surface,
The groove portion extends from one side of the nozzle row toward the other side, and holds the humidifying liquid by capillary force ,
A humidifying liquid detecting means for detecting the humidifying liquid held in the groove,
The humidifying liquid supply means includes
A humidifying liquid supply pressure chamber independent of the flow path of the liquid ejected from the nozzle, and a humidifying liquid supply pressure generating means for applying pressure fluctuation to the humidifying liquid supply pressure chamber;
Filling the humidifying liquid supply pressure chamber with the humidifying liquid, and driving the humidifying liquid supply pressure generating means to supply the humidifying liquid in the humidifying liquid supply pressure chamber to the groove portion. Features.

According to this configuration, the groove portion is formed at a position off the nozzle opening on the nozzle opening surface, and the groove portion holds the humidifying liquid by the capillary force, so that the humidifying liquid held in the groove portion evaporates. By humidifying the atmosphere, the humidity near the nozzle can be maintained at a higher level. Thereby, the evaporation of the liquid from a nozzle is suppressed and the raise of a liquid viscosity is suppressed. As a result, ejection failure due to thickening of the liquid, that is, malfunction such as the amount of the ejected liquid and the flying speed being significantly reduced from the design target values, or the liquid not being ejected from the nozzle, is prevented. can do.
Further, since the humidifying liquid is held in the groove portion of the nozzle opening surface, it is possible to suppress static electricity from being transmitted from the nozzle to the pressure generating means, the drive circuit, and the like through the liquid.
Further, since a large-scale device such as a mechanism for sending the volatilizing liquid for humidification to the nozzle side is unnecessary, it is possible to suppress the increase in size of the device and the cost.
The humidifying liquid supply means includes a humidifying liquid detecting means for detecting the humidifying liquid held in the groove, and the humidifying liquid supply means is a pressure chamber for supplying a humidifying liquid independent of a flow path of the liquid ejected from the nozzle. And a humidifying liquid supply pressure generating means for applying a pressure fluctuation to the humidifying liquid supply pressure chamber, the humidifying liquid supply pressure chamber is filled with the humidifying liquid, and the humidifying liquid supply pressure generation is performed. By driving the means, the humidifying liquid in the humidifying liquid supply pressure chamber is supplied to the groove portions, so that the humidifying liquid can be supplied to each groove portion without unevenness.

In the above structure, before Symbol groove, formed in plural on the nozzle opening surface,
It is desirable that each groove part extends along the nozzle arrangement direction.
Further, the nozzle opening surface is provided with a plurality of the nozzle rows,
The groove is preferably provided between the two nozzle rows.
According to this structure, it can humidify with respect to each nozzle uniformly by the humidification liquid hold | maintained at the groove part.

Moreover, it is desirable that the humidifying liquid supply means arranges a humidifying liquid storage section storing the humidifying liquid above the nozzle opening surface in the gravity direction.
According to the said structure, the liquid for humidification can be supplied to the groove part side using gravity.

Further, in the above configuration, a wiping member for wiping the nozzle opening surface of the liquid jet head is provided,
The groove is preferably formed along the wiping direction of the wiping member.
According to the said structure, a possibility that a wiping member may be damaged by a groove part can be reduced.

Further, in the above configuration, when the humidifying liquid supply means does not detect the humidifying liquid, the humidifying liquid supply pressure is driven by driving the humidifying liquid supply pressure generating means. It is desirable to employ a configuration in which the chamber humidifying liquid is supplied to the groove.
According to the above configuration, the humidifying liquid can be retained in the groove portion without excess or deficiency.

In the above configuration, the liquid is ink.
The humidifying liquid may employ a configuration including one or more volatile components of ink.

Furthermore, it is desirable that a liquid repellent treatment is performed on the nozzle opening surface.
According to this structure, it is suppressed that the liquid for humidification hold | maintained at the groove part leaks to the outer side of a groove part. Thereby, it is possible to prevent the humidifying liquid from dripping from the liquid jet head. Various existing configurations can be adopted as the liquid repellent treatment.

The liquid ejecting head of the present invention has a nozzle opening surface provided with a nozzle row composed of a plurality of opened nozzles, fills a pressure chamber communicating with the nozzle with liquid, A liquid ejecting head capable of ejecting liquid droplets from the nozzle by applying a pressure fluctuation to the liquid;
A humidifying liquid supply means for supplying the humidifying liquid to the nozzle opening surface side;
A groove portion for supplying the humidifying liquid from the humidifying liquid supply means is formed at a position off the nozzle opening on the nozzle opening surface,
The groove portion extends from one side of the nozzle row toward the other side, and holds the humidifying liquid by capillary force ,
A humidifying liquid detecting means for detecting the humidifying liquid held in the groove,
The humidifying liquid supply means includes
A humidifying liquid supply pressure chamber independent of the flow path of the liquid ejected from the nozzle, and a humidifying liquid supply pressure generating means for applying pressure fluctuation to the humidifying liquid supply pressure chamber;
Filling the humidifying liquid supply pressure chamber with the humidifying liquid, and driving the humidifying liquid supply pressure generating means to supply the humidifying liquid in the humidifying liquid supply pressure chamber to the groove portion. Features.

According to this configuration, the groove portion is formed at a position off the nozzle opening on the nozzle opening surface, and the groove portion holds the humidifying liquid by the capillary force, so that the humidifying liquid held in the groove portion evaporates. By humidifying the atmosphere, the humidity near the nozzle can be maintained at a higher level. Thereby, the evaporation of the liquid from a nozzle is suppressed and the raise of a liquid viscosity is suppressed. As a result, ejection failure due to thickening of the liquid, that is, malfunction such as the amount of the ejected liquid and the flying speed being significantly reduced from the design target values, or the liquid not being ejected from the nozzle, is prevented. can do.
Further, since the humidifying liquid is held in the groove portion of the nozzle opening surface, it is possible to suppress static electricity from being transmitted from the nozzle to the pressure generating means, the drive circuit, and the like through the liquid.

FIG. 3 is a perspective view illustrating a configuration of a printer. FIG. 3 is a plan view of the recording head as viewed from the nozzle opening surface side. FIG. 3 is a perspective view illustrating a configuration of a recording head. It is the sectional view on the AA line in FIG. FIG. 3 is a cross-sectional view of a main part of the recording head. FIG. 6 is a plan view of a recording head in a second embodiment. FIG. 6 is a perspective view of a recording head in a second embodiment. It is the sectional view on the AA line in FIG. FIG. 10 is a plan view of a recording head according to a third embodiment. FIG. 10 is a left side view of a recording head according to a third embodiment. FIG. 10 is a right side view of a recording head according to a third embodiment. It is the sectional view on the AA line in FIG. It is the BB sectional view taken on the line in FIG. It is CC sectional view taken on the line in FIG. It is an enlarged view of the area | region X in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In the embodiments described below, various limitations are made as preferred specific examples of the present invention. However, the scope of the present invention is not limited to the following description unless otherwise specified. However, the present invention is not limited to these embodiments. In the following, an ink jet recording apparatus (hereinafter referred to as a printer) will be described as an example of the liquid ejecting apparatus of the invention.

  The printer 1 shown in FIG. 1 has a cartridge mounting portion 2 to which an ink cartridge 5 storing ink (a kind of liquid in the present invention) is attached, and a humidifying liquid tank 17 described later (humidifying liquid in the present invention). A carriage 4 on which the recording head 3 (a kind of liquid ejecting head in the present invention) and a recording head 3 are mounted is provided. The carriage 4 is connected to a timing belt 10 installed between the drive pulley 8 and the idle pulley 9 while being supported by the guide rod 6. The drive pulley 8 is joined to the rotating shaft of the pulse motor 11. The operation of the pulse motor 11 causes the carriage 4 to move in the width direction of the recording paper 7 (recording medium or a kind of landing target), that is, main scanning. It is designed to move in the direction.

  A paper feed roller 12 is disposed below the guide rod 6 in parallel with the guide rod 6. The paper feed roller 12 is configured to be rotated by the driving force from the paper feed motor 13 to convey the recording paper 7 on the platen 14 in the sub-scanning direction.

  A home position serving as a base point for the movement of the recording head 3 is located in an end area outside the recording area in which an image or the like is printed on an ejection target such as recording paper within the movement range of the carriage 4. Is set. On the home position side, a capping mechanism 15 capable of capping (sealing) the nozzle opening surface of the recording head 3 and a wiping mechanism 16 for wiping the nozzle opening surface are disposed adjacent to each other. . The capping mechanism 15 includes a cap member 15 ′ that can seal the nozzle opening surface of the recording head 3, that is, the ejection side surface of the nozzle plate 31, and can move the cap member 15 ′ up and down. It is configured. The cap member 15 'is a substantially rectangular box in plan view, more specifically, a tray-like member having an open upper surface side, and the whole is made of an elastic material such as an elastomer. When the carriage 4 is positioned at the home position, the cap member 15 ′ moves upward to enter a capping state that seals the nozzle opening surface of the recording head 3. In this capping state, the nozzle 37 established on the nozzle opening surface faces the empty space inside the cap member 15 ', and the upper end edge of the cap member 15' and the nozzle opening surface are in close contact with each other. Accordingly, evaporation of the ink solvent from the nozzles of the recording head 3 is suppressed, and an increase in ink viscosity is suppressed. When the recording head 3 records an image or the like on the ejection target, the capping state of the cap member 15 ′ with respect to the nozzle opening surface is released. In addition, the nozzle opening surface in this invention is not restricted to the injection surface of the nozzle plate 31, Other members (for example, flow path) provided in the outer periphery (it is not restricted on the same surface) of the injection surface of the nozzle plate 31 When the substrate 30 or a metal cover is present, the member is also included in the nozzle opening surface. Therefore, the structure which provides the groove part 45 mentioned later to the said member is also employable.

  A wiping mechanism 16 is provided between the capping mechanism 15 and the recording area (platen 14). The wiping mechanism 16 has a wiper blade 16 '(a kind of wiping member in the present invention). The wiping mechanism 16 advances and retreats to and from a wiping position where the tip of the wiper blade 16 ′ overlaps the movement path of the recording head 3 and a retreat position where the tip of the blade 16 ′ is not in contact with the recording head 3. It is possible. When wiping the nozzle opening surface of the recording head 3, the wiper blade 16 ′ is moved to the wiping position, and the recording head 3 and the wiper blade 16 ′ are in contact with the tip of the wiper blade 16 ′ in contact with the nozzle opening surface. The wiper blade 16 'wipes the ink and the like adhering to the nozzle opening surface. In the present embodiment, the relative movement direction of the wiper blade 16 ′ with respect to the nozzle opening surface is parallel to the nozzle row 44.

  2 to 5 are diagrams for explaining the configuration of the recording head 3, the ink cartridge 5, and the humidifying liquid tank 17 in the first embodiment. FIG. 2 shows the nozzle 37 of the recording head 3 opened. FIG. 3 is a perspective view, and FIG. 4 is a cross-sectional view taken along line AA in FIG. 2 as viewed from the surface (nozzle plate 31) side. FIG. 5 is a cross-sectional view of the main part of the recording head 3 and shows only the configuration corresponding to one of the two nozzle rows 44. 2 to 4, the carriage 4 is not shown. Further, in FIG. 5, the configuration corresponding to the other nozzle row 44 is omitted because it is symmetrical in the left-right direction with that shown in FIG.

  The ink cartridge 5 and the humidifying liquid tank 17 are detachably attached to the carriage 4 so as to be positioned on the upper surface side of the recording head 3. In other words, the ink cartridge 5 and the humidifying liquid tank 17 are arranged above the nozzle opening surface (surface on the ejection side of the nozzle plate 31) of the recording head 3 in the gravity direction. As a result, ink and humidification liquid can be supplied to the recording head 3 side using gravity. The ink cartridge 5 is a member formed in the shape of a hollow box, and ink is accommodated in an ink storage space 5 ′ partitioned therein. In the present embodiment, two ink cartridges 5 can be attached to the recording head 3. An ink introduction needle 22 provided on the upper surface (the surface opposite to the nozzle opening surface) of the recording head 3 is inserted into the ink cartridge 5, and ink is stored through the ink introduction needle 22. Ink stored in the void 5 ′ is introduced into an ink flow path (a type of liquid flow path) inside the recording head 3. The humidifying liquid tank 17 is a member formed in the shape of a hollow box like the ink cartridge 5, and the nozzle opening surface of the recording head 3 is located in the humidifying liquid storage space 17 ′ partitioned inside the ink cartridge 5. Contains a humidifying liquid for humidifying. The humidifying liquid storage space 17 ′ communicates with the humidifying liquid supply path 27 formed in the case 23 of the recording head 3 through the humidifying liquid supply tube 18. The humidifying liquid is a liquid for increasing the humidity of the nozzle opening surface by being held in a groove 45 described later. As the humidifying liquid, pure water, an ink solvent, or the like can be used. From the viewpoint of humidifying the nozzle opening surface, it is desirable that the humidifying liquid contains one or more volatile components of the ink. As the volatile component, petroleum or alcohol can be employed. In this embodiment, the ink cartridge 5 and the humidifying liquid tank 17 are mounted on the carriage 4. However, the present invention is not limited to this. For example, the ink cartridge 5 and the humidifying liquid tank 17 are arranged on the main body side of the printer 1 and the ink and the humidifying liquid stored in the ink cartridge 5 and the humidifying liquid tank 17 are supplied to the recording head 3 side through a supply tube or the like. It is also possible to adopt.

  The humidifying liquid supply path 27 is a flow path formed in the recording head 3 independently at a position outside the ink flow path. The humidifying liquid supply path 27 in the present embodiment includes a lateral flow path 27a parallel to the nozzle opening surface (nozzle plate 31) and a vertical flow path 27b perpendicular to the nozzle opening surface. The lateral flow path 27a is a flow path having one end opened on the side surface of the case 23 and the other end extending to a position corresponding to the space between the nozzle rows. The lateral flow paths 27 a are formed at both ends of the case 23 in the nozzle row direction, and are located on the upper surface side opposite to the nozzle opening surface in the height direction of the case 23. The humidifying liquid supply tube 18 is connected in a liquid-tight state to one end of each horizontal flow path 27a. On the other hand, the vertical flow path 27b is a flow path whose upper end communicates with the horizontal flow path 27a, and whose lower end is opened in a groove 45 (described later) on the nozzle opening surface, as shown in FIG. And is formed over the constituent members (the diaphragm 32 and the flow path substrate 30) of the recording head 3 including the case 23. Therefore, the humidifying liquid that has flowed from the humidifying liquid tank 17 into the humidifying liquid supply path 27 through the humidifying liquid supply tube 18 passes through the horizontal flow path 27a and the vertical flow path 27b into the groove 45 on the nozzle opening surface. It comes to be supplied. Therefore, the humidifying liquid tank 17 and the humidifying liquid supply path 27 correspond to a kind of humidifying liquid supply means in the present invention.

Next, a configuration for ejecting ink of the recording head 3 will be described.
The recording head 3 includes a case 23, a vibrator unit 24 housed in the case 23, a flow path unit 25 joined to the bottom surface (tip surface) of the case 23, and the like. The case 23 is made of, for example, an epoxy resin, and a housing empty portion 26 for housing the vibrator unit 24 is formed therein. The vibrator unit 24 includes a piezoelectric vibrator 20 that functions as a kind of pressure generating means, a fixed plate 28 to which the piezoelectric vibrator 20 is joined, and a flexible cable 29 for supplying a drive signal and the like to the piezoelectric vibrator 20. And. The piezoelectric vibrator 20 is a laminated type produced by cutting a piezoelectric plate in which piezoelectric layers and electrode layers are alternately laminated into a comb-like shape, and can be expanded and contracted in a direction perpendicular to the lamination direction (electric field direction). This is a piezoelectric vibrator in a longitudinal vibration mode (field transverse effect type).

  The flow path unit 25 is configured by joining a nozzle plate 31 to one surface of the flow path substrate 30 and a diaphragm 32 to the other surface of the flow path substrate 30. The flow path unit 25 is provided with a reservoir 33 (common liquid chamber), an ink supply port 34, a pressure chamber 35, a nozzle communication port 36, and a nozzle 37. A series of ink flow paths from the ink supply port 34 to the nozzle 37 through the pressure chamber 35 and the nozzle communication port 36 are formed corresponding to each nozzle 37.

  The nozzle plate 31 is a member in which a plurality of nozzles 37 are formed in rows at a pitch (for example, 180 dpi) corresponding to the dot formation density. In the present embodiment, the nozzle plate 31 is made of, for example, stainless steel. The nozzle plate 31 may be made of a silicon single crystal substrate. The nozzle plate 31 is characterized in that a groove 45 for holding the humidifying liquid is provided on a surface (nozzle opening surface) on the ink ejection side. Details of this point will be described later.

  The diaphragm 32 has a double structure in which an elastic film 39 is laminated on the surface of a support plate 38. In this embodiment, the vibration plate 32 is manufactured using a composite plate material in which a stainless steel plate, which is a kind of metal plate, is used as the support plate 38 and a resin film is laminated on the surface of the support plate 38 as an elastic film 39. The diaphragm 32 is provided with a diaphragm portion 40 that changes the volume of the pressure chamber 35. The diaphragm 32 is provided with a compliance portion 41 that seals a part of the reservoir 33.

  The diaphragm 40 is produced by partially removing the support plate 38 by etching or the like. That is, the diaphragm portion 40 includes an island portion 42 to which a free end portion of the piezoelectric vibrator 20 is joined, and a thin elastic portion 43 surrounding the island portion 42. The compliance part 41 is produced by removing the support plate 38 in the region facing the opening surface of the reservoir 33 by etching or the like in the same manner as the diaphragm part 40, and the pressure fluctuation of the liquid stored in the reservoir 33 is reduced. Functions as a damper to absorb.

  Since the tip surface of the piezoelectric vibrator 20 is joined to the island portion 42, the volume of the pressure chamber 35 can be changed by expanding and contracting the free end of the piezoelectric vibrator 20. A pressure fluctuation occurs in the ink in the pressure chamber 35 along with the volume fluctuation. The recording head 3 ejects ink droplets from the nozzles 37 using this pressure fluctuation. Although not shown, the recording head 3 is attached with a metal head cover that covers the peripheral edge of the nozzle opening surface. The head cover is connected to a ground line, and is electrically connected to the nozzle plate 31 so that, for example, static electricity generated from the recording paper 7 or the like is transmitted through the nozzle plate, thereby damaging the driving IC or the like. And malfunctions such as malfunctions are prevented.

The nozzle plate 31 is provided with a plurality of nozzles 37 and a nozzle row 44 (nozzle group). One nozzle row 44 is composed of, for example, 180 nozzles 37. In this embodiment, two nozzle rows 44 are formed side by side in the moving direction of the recording head 3. A groove portion 45 is formed at a position on the ejection side surface (nozzle opening surface) of the nozzle plate 31 that is deviated (avoided) from the opening of the nozzle 37. As shown in FIG. 5, the groove 45 is a groove set to a width and a depth that allow the above-mentioned humidifying liquid to be held by capillary force, and is opposite from the nozzle opening surface side of the nozzle plate 31. The nozzle plate 31 is formed in a state of being depressed halfway toward the side (the ink flow path side such as the pressure chamber 35). As shown in FIG. 2, the groove 45 in the present embodiment has five first grooves 45 a extending in parallel along the nozzle row direction, and extends in a direction perpendicular to the nozzle row on both sides in the nozzle row direction. The second groove 45b intersects with each first groove 45a. As described above, the lower end of the longitudinal flow path 27b is open at the center of the second groove 45b. Since these groove portions 45 communicate with each other, the humidifying liquid flowing out from the opening of the longitudinal flow path 27b spreads to the groove portions 45a and 45b by capillary action. And each groove part 45 is comprised so that the liquid for humidification may be hold | maintained by capillary force. Note that the number and positions of the groove portions 45 formed on the nozzle opening surface are not limited to those exemplified in this embodiment, but at least the groove portions 45 are formed along the nozzle row direction at positions closer to the nozzle row. By forming, each nozzle 37 can be uniformly humidified by the humidifying liquid held in the groove 45.
In addition, it is desirable that a region other than the nozzle 37 and the groove 45 on the nozzle opening surface of the nozzle plate 31 is subjected to a liquid repellent treatment. Thereby, it becomes difficult for ink to adhere to the nozzle opening surface, and the wiping performance of the nozzle opening surface by wiping of the wiping mechanism 16 is improved. Further, the humidifying liquid held in the groove 45 is prevented from leaking outside the groove 45. Thereby, it is possible to prevent the humidifying liquid from dripping from the recording head 3. An existing configuration can be adopted as the liquid repellent treatment.

In the recording head 3 having the above-described configuration, the groove 45 formed on the nozzle opening surface holds the humidifying liquid by capillary force. Therefore, even if the nozzle opening surface is released from capping by the capping mechanism 15, When the humidifying liquid held in 45 evaporates and is humidified in the atmosphere, the humidity in the vicinity of the nozzle 37 can be maintained at a higher level. Thereby, evaporation of the ink solvent from the nozzle 37 is suppressed, and an increase in ink viscosity is suppressed. As a result, ejection failure due to ink thickening, that is, the amount of ejected ink and the flying speed are significantly reduced from the design target values, or the ink is not ejected from the nozzle 37, etc. Can be prevented.
In addition, since a large-scale device such as a mechanism for volatilizing the humidifying liquid and sending it to the nozzle side is unnecessary, it is possible to suppress the increase in size of the device and the cost.
Further, even in a recording head having a plurality of nozzle rows, it is possible to uniformly humidify the nozzles 37 without unevenness by providing the groove portions 45 along the nozzle rows.
Further, since the humidity in the vicinity of the nozzle 37 is maintained at a higher level, for example, static electricity generated from the recording paper 7 or the like is transmitted from the nozzle 37 through the ink to the piezoelectric vibrator 20 or the drive circuit and is damaged. It is suppressed. In particular, when a highly insulating liquid-repellent film or the like is formed on the nozzle opening surface, static electricity can be discharged to the humidifying liquid side held in the groove 45, and troubles due to static electricity can be more effectively prevented. Can be prevented.

Next, a second embodiment of the present invention will be described.
6 to 8 are diagrams illustrating the configuration of the present embodiment. FIG. 6 is a plan view of the recording head 3 viewed from the nozzle opening surface side, FIG. 7 is a perspective view, and FIG. It is A sectional view. The present embodiment is different from the first embodiment in that only five first groove portions 45a are formed and the second groove portion 45b is not formed with respect to the groove portion 45. That is, the groove 45 in the present embodiment is a first portion extending along the wiping direction of the wiper blade 16 ′ during wiping (the relative movement direction of the nozzle opening surface and the wiper blade 16 ′, indicated by an arrow in FIG. 6). It is comprised only by the groove part 45a. Thereby, when the wiper blade 16 'is wiped, there is no groove 45 in the direction intersecting with the wiping direction, and the groove 45 is not crossed, so that the wiper blade 16' can be prevented from being damaged. Further, it is possible to suppress an increase in operation sound during wiping. In addition, since there is no groove 45 on both sides in the wiping direction with respect to the nozzle row 44 (that is, on both sides of the nozzle row), when wiping with the wiper blade 16 ′, the humidifying liquid held in the groove portion 45 is transferred to the nozzle 37. Can be prevented from being mixed with ink. In addition, although each 1st groove part 45a becomes a mutually independent groove | channel, the longitudinal flow path 27b is opened at both ends, respectively. As shown in FIG. 8, since the vertical flow paths 27b corresponding to the respective groove portions 45a communicate with the horizontal flow paths 27a at the upper ends, the humidifying liquid from the humidifying liquid tank 17 is transferred to the horizontal flow paths 27a. In addition, the liquid is supplied to the corresponding groove 45a of the nozzle opening surface through each longitudinal flow path 27b. Since other configurations are the same as those in the first embodiment, description thereof is omitted.

Next, a third embodiment of the present invention will be described.
9 to 15 are diagrams for explaining the configuration of the present embodiment. FIG. 9 is a plan view of the recording head 3 as viewed from the nozzle opening surface side, FIG. 10 is a left side view of the recording head 3, and FIG. FIG. 4 is a right side view of the recording head. 12 is a cross-sectional view taken along line AA in FIG. 9, and FIG. 13 is a cross-sectional view taken along line BB in FIG. 14 is a cross-sectional view taken along the line CC in FIG. 10, and FIG. 15 is an enlarged view of a region X in FIG. In the present embodiment, one of the configurations for ejecting ink (the configuration of the flow path from the reservoir 33 to the pressure chamber 35 and the piezoelectric vibrator 20 and the like) is used as a supply pump (liquid feeding means) for humidification. The point which is comprised so that a liquid may be supplied to the groove part 45 differs from said each embodiment. More specifically, in the humidifying liquid reservoir 33 ′, the humidifying liquid supply port 34 ′, the humidifying liquid supply pressure chamber 35 ′, and the humidifying liquid supply pressure chamber 35 ′ independent of the ink flow path. A humidifying liquid supplying piezoelectric vibrator 20 '(a kind of humidifying liquid supplying pressure generating means) is provided. The configuration for supplying the humidifying liquid (part of the humidifying liquid supply means in the present invention) is basically the same as the configuration for ejecting ink, but the configuration for supplying the humidifying liquid is used. The difference is that the nozzle 37 is not provided.

As shown in FIG. 13, the humidifying liquid tank 17 communicates with the introduction flow path 46 formed in the case 23 of the recording head 3 through the humidification liquid supply tube 18. Communicates with the humidifying liquid reservoir 33 '. Therefore, the humidifying liquid that has flowed from the humidifying liquid tank 17 into the introduction flow path 46 through the humidifying liquid supply tube 18 is supplied through the humidifying liquid reservoir 33 ′ and the humidifying liquid supply port 34 ′. To the pressure chamber 35 '. One end of the communication channel 47 is opened on the side surface of the humidifying liquid supply pressure chamber 35 ′ opposite to the adjacent pressure chamber 35 for ink. As shown in FIG. 12, the other end of the communication channel 47 communicates with the lateral channel 27 a of the humidifying liquid supply channel 27. When the humidifying liquid supply piezoelectric vibrator 20 ′ is driven with the above-described configuration, the volume of the humidifying liquid supply pressure chamber 35 ′ fluctuates, and the humidifying liquid supply pressure chamber 35 varies with the volume fluctuation. Pressure fluctuation occurs in the humidifying liquid filled in the ′. Then, using this pressure fluctuation, the humidifying liquid can be supplied to each groove 45 from the humidifying liquid supply pressure chamber 35 ′ through the communication flow path 47 and the humidifying liquid supply path 27. Thereby, the liquid for humidification can be supplied to each groove part 45 without unevenness. Moreover, when the humidifying liquid is initially filled in each groove 45, the filling can be completed in a shorter time.
In addition, about the structure which functions as a pump for liquids for humidification, you may provide two or more. Further, instead of using the humidifying liquid supply pressure chamber 35 ′, the humidifying liquid supply piezoelectric vibrator 20 ′, and the like, a pump mechanism having another configuration may be used as the liquid feeding means for the humidifying liquid. .

The present embodiment is also characterized in that humidifying liquid detection means for detecting whether or not the humidifying liquid is held in the groove 45 is provided.
As shown in FIG. 14, in the recording head 3, an optical path 48 that crosses the direction orthogonal to the nozzle row is formed at one end in the nozzle row direction. The optical path 48 is a cylindrical hollow portion through which light can pass. A light emitting element 49 is disposed at one end (right end in FIG. 14) of the optical path 48, and a light receiving element 50 is disposed at the other end (left end in FIG. 14). The light emitting element 49 is composed of, for example, a light emitting diode. The light receiving element 50 is configured by a photodiode or a phototransistor. One of the groove portions 45 (the middle groove portion 45 in the example of FIG. 14) communicates with the optical path 48. As shown in FIG. 15, bending members 51 a and 51 b made of a member that can transmit light, such as transparent plastic or glass, are provided on both sides so as to sandwich the communicating portion between the groove 45 and the optical path 48. Each of the bent members 51a and 51b is formed in a dome shape, and is attached so as to block the optical path 48 in a state in which the surfaces of the depressed central portions face each other. While the humidifying liquid can flow into the space between the bending members 51a and 51b, the humidifying liquid does not flow out to the optical path 48 outside the bending members 51a and 51b. ing. In the present embodiment, the optical path 48, the light emitting element 49, the light receiving element 50, and the bending members 51a and 51b function as the humidifying liquid detection means in the present invention.

  When the groove 45 is not filled with the humidifying liquid and the humidifying liquid does not exist in the bending members 51a and 51b, the light from the light emitting element 49 is reflected by the bending members as indicated by Da in FIG. When the light passes through 51a and 51b, the light is diffused, so that the amount of light received by the light receiving element 50 is relatively small. On the other hand, when the groove 45 is sufficiently filled with the humidifying liquid and the bending members 51a and 51b are also filled with the humidifying liquid, both the bending members 51a and 51b and the humidifying liquid therebetween condense. Acting like a lens, the light from the light emitting element 49 is refracted and condensed on the light receiving element 50 as indicated by Db in FIG. In this case, the amount of received light increases compared to the case where the moisturizing liquid is not filled in the groove 45, and the detection signal increases accordingly. The refractive index of water is about 1.33 when air is 1.

  A detection signal from the light receiving element 50 is output to a control unit (not shown) of the printer 1 main body. Therefore, the control unit can determine whether the groove 45 is filled with the humidifying liquid based on the magnitude of the detection signal of the light receiving element 50. By setting a threshold value in advance and comparing this threshold value with the detection signal, it can be determined whether or not the dampening liquid is filled in the groove 45. The control unit functions as a part of the humidifying liquid supply means, and controls the humidifying liquid supply piezoelectric vibrator 20 ′ based on the detection signal, thereby holding the humidifying liquid in the groove 45 without excess or deficiency. And can be stably humidified. For example, when the humidifying liquid in the groove 45 is not detected, the humidifying liquid supplied in the humidifying liquid supply pressure chamber 35 ′ is driven by driving the humidifying liquid supplying piezoelectric vibrator 20 ′. To supply. Other configurations are the same as those in the second embodiment, and the description thereof is omitted.

  In the above, an ink jet printer which is a kind of liquid ejecting apparatus has been described as an example, but the present invention can also be applied to other liquid ejecting apparatuses. For example, a display manufacturing apparatus that manufactures color filters such as liquid crystal displays, an electrode manufacturing apparatus that forms electrodes such as organic EL (Electro Luminescence) displays and FEDs (surface emitting displays), and chips that manufacture biochips (biochemical elements) The present invention can also be applied to a manufacturing apparatus and a micropipette that supplies an accurate amount of a very small amount of sample solution. In the display manufacturing apparatus, a solution of each color material of R (Red), G (Green), and B (Blue) is ejected from the color material ejecting head. Moreover, in an electrode manufacturing apparatus, a liquid electrode material is ejected from an electrode material ejection head. In the chip manufacturing apparatus, a bioorganic solution is ejected from a bioorganic ejecting head.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 3 ... Recording head, 15 ... Capping mechanism, 16 ... Wiping mechanism, 16 '... Wiper blade, 17 ... Humidifying liquid tank, 20 ... Piezoelectric vibrator, 20' ... Piezoelectric vibrator for humidifying liquid supply 27 ... Humidification liquid supply path, 31 ... Nozzle plate, 33 ... Reservoir, 33 '... Humidification liquid reservoir, 34 ... Ink supply port, 34' ... Humidification liquid supply port, 35 ... Pressure chamber, 35 '... Humidification Liquid supply pressure chamber, 37 ... nozzle, 44 ... nozzle row, 45 ... groove, 46 ... introduction flow path, 47 ... communication flow path, 48 ... optical path, 49 ... light emitting element, 50 ... light receiving element, 51 ... curved member

Claims (9)

A nozzle opening surface provided with a nozzle array composed of a plurality of nozzles that are opened; filling a pressure chamber communicating with the nozzle with liquid; and applying pressure fluctuations to the liquid in the pressure chamber A liquid ejecting apparatus including a liquid ejecting head capable of ejecting liquid droplets from a nozzle,
A humidifying liquid supply means for supplying the humidifying liquid to the nozzle opening surface side;
A groove portion for supplying the humidifying liquid from the humidifying liquid supply means is formed at a position off the nozzle opening on the nozzle opening surface,
The groove portion extends from one side of the nozzle row toward the other side, and holds the humidifying liquid by capillary force ,
A humidifying liquid detecting means for detecting the humidifying liquid held in the groove,
The humidifying liquid supply means includes
A humidifying liquid supply pressure chamber independent of the flow path of the liquid ejected from the nozzle, and a humidifying liquid supply pressure generating means for applying pressure fluctuation to the humidifying liquid supply pressure chamber;
Filling the humidifying liquid supply pressure chamber with the humidifying liquid, and driving the humidifying liquid supply pressure generating means to supply the humidifying liquid in the humidifying liquid supply pressure chamber to the groove portion. A liquid ejecting apparatus. A plurality of the groove portions are formed on the nozzle opening surface,
The liquid ejecting apparatus according to claim 1, wherein each groove portion extends along a direction in which the nozzles are arranged. A plurality of the nozzle rows are provided on the nozzle opening surface,
The liquid ejecting apparatus according to claim 1, wherein the groove is provided between the two nozzle rows.   4. The humidifying liquid supply means arranges a humidifying liquid storage part that stores a humidifying liquid above the nozzle opening surface in a gravitational direction. The liquid ejecting apparatus according to one item. A wiping member for wiping the nozzle opening surface of the liquid jet head;
The liquid ejecting apparatus according to claim 1, wherein the groove is formed along a wiping direction of the wiping member. The humidifying liquid supply means drives the humidifying liquid supply pressure generating means to drive the humidifying liquid supply pressure chamber when the humidifying liquid detection means does not detect the humidifying liquid. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting apparatus is supplied to the groove portion. The liquid is ink;
The humidification liquid to a liquid ejecting apparatus according to any one of claims 1 to 6, characterized in that it comprises a volatile component of the ink one or more. Wherein the nozzle opening surface, the liquid ejecting apparatus according to any one of claims 1 to 7, characterized in that the liquid-repellent treatment is applied. A nozzle opening surface provided with a nozzle array composed of a plurality of nozzles that are opened; filling a pressure chamber communicating with the nozzle with liquid; and applying pressure fluctuations to the liquid in the pressure chamber A liquid ejecting head capable of ejecting liquid droplets from a nozzle,
  A humidifying liquid supply means for supplying the humidifying liquid to the nozzle opening surface side;
  A groove portion for supplying the humidifying liquid from the humidifying liquid supply means is formed at a position off the nozzle opening on the nozzle opening surface,
  The groove portion extends from one side of the nozzle row toward the other side, and holds the humidifying liquid by capillary force,
  A humidifying liquid detecting means for detecting the humidifying liquid held in the groove,
  The humidifying liquid supply means includes
  A humidifying liquid supply pressure chamber independent of the flow path of the liquid ejected from the nozzle, and a humidifying liquid supply pressure generating means for applying pressure fluctuation to the humidifying liquid supply pressure chamber;
  Filling the humidifying liquid supply pressure chamber with the humidifying liquid, and driving the humidifying liquid supply pressure generating means to supply the humidifying liquid in the humidifying liquid supply pressure chamber to the groove portion. A liquid ejecting head.

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