JP2019018427A - Liquid jet head and liquid jet head inspection method - Google Patents

Abstract

To provide a liquid jet head which inhibits liquid entry into a gas path, and to provide a liquid jet head inspection method.SOLUTION: A liquid jet head (a recording head 7) includes: a nozzle (86); a first member (a second external cover 37, an intermediate passage member 33 etc.) having a space (a lower space 52 etc.), a first connection passage (a first gas connection passage 51) communicating with the space (the lower space 52 etc.), and a first liquid path (a lower insertion passage 49 etc.); and a second member (a valve unit 34) having a gas path (53) leading from a second connection passage (a second gas connection passage 54) to an opening and a second liquid path (a lower passage 65 etc.). The liquid jet head (the recording head 7) is characterized in that the first member (the second external cover 37, the intermediate passage member 33 etc.) and the second member (the valve unit 34) are detachably attached in a state where the first connection passage (the first gas connection passage 51) and the second connection passage (the second gas connection passage 54) are connected in an airtight manner.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a liquid ejecting head including a gas path and a liquid path, and an inspection method for the liquid ejecting head.

  The liquid ejecting head is a device that ejects various liquids from nozzles, and is mounted on a liquid ejecting apparatus or the like. As this liquid ejecting apparatus, for example, there is an image recording apparatus such as an ink jet printer or an ink jet plotter, but recently, various types of manufacturing have been made by taking advantage of the ability to accurately land a very small amount of liquid on a predetermined position. It is also applied to devices. For example, a display manufacturing apparatus for manufacturing a color filter such as a liquid crystal display, an electrode forming apparatus for forming an electrode such as an organic EL (Electro Luminescence) display or FED (surface emitting display), and a chip for manufacturing a biochip (biochemical element) Applied to manufacturing equipment. The recording head for the image recording apparatus ejects liquid ink, and the color material ejecting head for the display manufacturing apparatus ejects solutions of R (Red), G (Green), and B (Blue) color materials. The electrode material ejecting head for the electrode forming apparatus ejects a liquid electrode material, and the bioorganic matter ejecting head for the chip manufacturing apparatus ejects a bioorganic solution.

  The liquid ejecting head includes a plurality of members and includes a liquid path that supplies liquid to the nozzle. In addition, some liquid ejecting heads include a gas path that communicates with a space formed inside (see, for example, Patent Document 1). The liquid path and the gas path are formed across a plurality of members, and are connected by, for example, inserting a needle-shaped portion formed in one member into the other member at a connection portion between adjacent members. Yes.

Japanese Patent Laying-Open No. 2015-189139

  By the way, while the connection part of the liquid path | route in patent document 1 mentioned above is connected via a sealing member, the connection part of a gas path | route is connected not via a sealing member, and the clearance gap is formed between members. . The gas path is open to the atmosphere through this gap. For this reason, for example, when connecting adjacent members, liquid leaked from the connection portion of the liquid path may enter the inside of the gas path from the gap in the connection portion of the gas path. As a result, for example, liquid may adhere to a circuit disposed in a space communicating with the gas path, and the circuit may be destroyed.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid ejecting head in which intrusion of liquid into a gas path is suppressed, and an inspection method for the liquid ejecting head. .

The liquid jet head of the present invention has been proposed in order to achieve the above object, and a nozzle for jetting liquid;
A first member having a space, a first connection path communicating with the space, and a first liquid path for supplying a liquid to the nozzle;
A gas path from a second connection path connected to the first connection path to an opening that opens to a position different from the position facing the space; and the first liquid path and an external flow path. A second member having a second liquid path to be communicated,
The first member and the second member are detachably attached in a state where the first connection path and the second connection path are hermetically connected.

  According to this structure, since the 1st connection path and the 2nd connection path were connected airtightly, it can suppress that a liquid approachs into space through this connection location. Further, since the second member has a gas path, the distance from the other member connected to the opening or the atmosphere to the space becomes long. Thereby, even if the liquid enters from the opening, the liquid can be prevented from reaching the space. As a result, it is possible to suppress, for example, a circuit or the like disposed in the space from being destroyed or soiled. Furthermore, since the first member and the second member are detachably attached, it is easy to replace the first member or the second member.

  In the above configuration, it is desirable that the first connection path and the second connection path are connected via an elastic member.

  According to this structure, the airtightness in the connection location of a 1st connection path and a 2nd connection path can be improved.

In any of the above-described configurations, either one of the first connection path and the second connection path is formed in a protruding portion protruding from the first member or the second member. And
The first connection path and the second connection path are connected by inserting the protruding portion into the other connection path of the first connection path or the second connection path. Is desirable.

  According to this configuration, the connection between the first connection path and the second connection path is facilitated.

Furthermore, in the said structure, an elastic member is provided between the said protrusion part and the inner wall face of the said other connection path,
The elastic member is preferably attached to an inner wall surface of the other connection path.

  According to this configuration, it is possible to reduce the frictional force received from the elastic member when the protruding portion is inserted into the other connection path as compared with the case where the elastic member is disposed around the protruding portion. Thereby, the connection between the first connection path and the second connection path is further facilitated.

  In any one of the above-described configurations, it is preferable that a flange portion protruding from the inner wall surface is formed inside the one connection path.

  According to this configuration, even when the liquid enters the inside of the connection path, it is possible to further suppress the liquid from reaching the space by the collar portion.

  Furthermore, in any of the above-described configurations, it is preferable that the protruding portion tapers toward the tip.

  According to this configuration, the connection between the first connection path and the second connection path is further facilitated. Moreover, it becomes difficult for the liquid to enter the first connection path or the second connection path by opening the first connection path or the second connection path at the tip of the protrusion.

  In the above configuration, it is preferable that the one connection path is opened in a direction intersecting a protruding direction of the protruding portion at a tip portion of the protruding portion.

  According to this configuration, the liquid becomes more difficult to enter the first connection path or the second connection path.

In any of the above-described configurations, the first member has a third connection path different from the first connection path,
The second member has a fourth connection path different from the second connection path,
It is desirable that the third connection path and the fourth connection path are connected at a position different from a connection location between the first connection path and the second connection path.

  According to this configuration, since there are at least two connection portions between the first member and the second member, misalignment between the first member and the second member is difficult to occur.

Furthermore, in any one of the above configurations, a flexible member having flexibility is disposed on the inner wall surface of either the space or the gas path,
It is desirable that at least a part of the space or the gas path is partitioned from the outer space by the flexible member.

  According to this configuration, the flexible member can be deformed by sending gas to the gas path. Thereby, an external force can be applied to a mechanism (for example, a pressure receiving member) disposed in the outer space.

The liquid jet head inspection method of the present invention is a liquid jet head inspection method according to any of the above-described configurations,
A connecting step of connecting the first connection path and the second connection path;
After the connection step, in a state where the first connection path and the second connection path are connected, an airtight inspection step of sending a fluid from the opening of the gas path;
It is characterized by going through.

  According to this configuration, the airtightness test can be easily performed.

  Further, in the above inspection method, after the connection step and before the airtightness inspection step, the cleaning liquid is discharged from the opening of the gas path in a state where the first connection path and the second connection path are connected. It is desirable to pass through a cleaning process in which a cleaning liquid is passed through the first liquid path and the second liquid path without introducing water.

  According to this configuration, the cleaning liquid can be prevented from entering the space.

2 is a plan view illustrating a configuration of a printer. FIG. FIG. 2 is a side view illustrating the configuration of a printer. FIG. 3 is an exploded perspective view of a recording head unit. It is a perspective view of a recording head. FIG. 6 is a bottom view of the recording head. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. It is sectional drawing explaining the structure of a unit head. It is sectional drawing to which the connection part of a 2nd inner cover and a valve unit was expanded. 6 is a flowchart illustrating a flow of a recording head inspection method. It is sectional drawing to which the connection part of the intermediate | middle flow path and valve unit in 2nd Embodiment was expanded. It is sectional drawing to which the connection part of the intermediate flow path and valve unit in 3rd Embodiment was expanded. FIG. 10 is a perspective view of a recording head in a fourth embodiment. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. It is CC sectional drawing in FIG. FIG. 10 is a cross-sectional view of a recording head in a fifth embodiment.

  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 printer (hereinafter referred to as a printer) 1 will be described as an example of an apparatus including a liquid ejecting head.

  FIG. 1 is a plan view schematically illustrating the configuration of the printer 1, and FIG. 2 is a side view schematically illustrating the configuration of the printer 1. The printer 1 includes a recording head unit 2 (a kind of liquid ejecting head in a broad sense), an ink tank 3, a paper feed roller 4, a transport mechanism 5, and the like. The recording head unit 2 is an apparatus in which a plurality of recording heads 7 (a kind of liquid ejecting head in a narrow sense) for recording an image or the like by ejecting ink which is a kind of liquid are arranged, and a recording paper 6 (a recording medium or a recording medium). It is formed in a long shape along the paper width direction (a kind of landing target) (direction perpendicular to the conveyance direction of the recording paper 6). The ink tank 3 is a kind of liquid supply source in which ink to be supplied to the recording head unit 2 is stored. The ink in the ink tank 3 is supplied to the recording head unit 2 via the liquid supply tube 8. A configuration in which the liquid supply source is mounted above the recording head unit 2 can also be employed. The detailed configuration of the recording head unit 2 will be described later.

  The paper feed roller 4 is disposed on the upstream side of the transport mechanism 5. The paper feed roller 4 is composed of a pair of upper and lower rollers 4a and 4b that can rotate synchronously in opposite directions while sandwiching a recording paper 6 fed from a paper feed unit (not shown). The paper feed roller 4 is driven by power from the paper feed motor 9 and cooperates with a skew correction roller (not shown) to incline with respect to the transport direction of the recording paper 6 and a direction perpendicular to the transport direction (paper width of the recording paper 6). The recording paper 6 is supplied to the transport mechanism 5 side after correcting the positional deviation in the direction).

  The transport mechanism 5 includes a transport belt 11, a transport motor 12, a driving roller 13, a driven roller 14, a tension roller 15, and a pressure contact roller 16. The transport motor 12 is a drive source of the transport mechanism 5 and is a mechanism that transmits power to the drive roller 13. The conveyor belt 11 is an endless belt, and is stretched between the driving roller 13 and the driven roller 14. The tension roller 15 is a roller that abuts on the inner peripheral surface of the transport belt 11 between the driving roller 13 and the driven roller 14 and applies tension to the transport belt 11 by the biasing force of a biasing member such as a spring. The pressure roller 16 is a roller that is disposed immediately above the driven roller 14 with the conveyance belt 11 interposed therebetween, and presses the recording paper 6 toward the conveyance belt 11.

  On the outer peripheral surface of the conveyor belt 11, a linear scale 18 is disposed over the entire circumference. The linear scale 18 is a plurality of slit-shaped detection patterns arranged in a constant interval (for example, 360 dpi) in the conveyance direction of the conveyance belt 11. The detection pattern of the linear scale 18 is optically detected by the detection head 19, and the detection signal is output as an encoder signal to a control unit (not shown) of the printer 1. Therefore, the control unit can grasp the conveyance amount of the recording paper 6 by the conveyance mechanism 5 (conveyance belt 11) based on the encoder signal. The encoder signal defines the generation timing of a drive signal for driving a piezoelectric element 93 (described later) of the unit head 32.

  Next, the recording head unit 2 will be described with reference to FIGS. FIG. 3 is an exploded perspective view of the recording head unit 2. FIG. 4 is a perspective view of the recording head 7. FIG. 5 is a bottom view of the recording head 7. 6 is a cross-sectional view taken along line AA in FIG. 7 is a cross-sectional view taken along the line BB in FIG. In the following description, the stacking direction of the constituent members of the recording head unit 2 will be described as the vertical direction as appropriate.

  As shown in FIG. 3, the recording head unit 2 in this embodiment includes a supply member 22 that distributes ink to each recording head 7, a plurality (six in this embodiment) of recording heads 7, and each recording head 7. Is provided with a base plate 23 to which is attached. The supply member 22 is a member made of synthetic resin or the like to which the liquid supply tube 8 is connected. Inside the supply member 22 is formed a liquid flow path (not shown) having one end communicating with the liquid supply tube 8 and the other end communicating with the liquid inlet 24 of the recording head 7. Further, a circuit board (not shown) connected to the connector 25 of the recording head 7 is disposed inside the supply member 22 in the present embodiment. The liquid flow path and the circuit board are configured to be connected to the liquid inlet 24 and the connector 25 of the recording head 7 on the lower surface of the supply member 22, respectively.

  The base plate 23 is a hard plate material made of metal, for example. The recording head 7 is fixed in a state of being positioned on the base plate 23. The base plate 23 in the present embodiment includes a plurality of base through holes 26 that penetrate in the thickness direction and expose the lower surface of each recording head 7. By inserting the lower part of the recording head 7 into the base through hole 26, the relative position between the recording heads 7 can be defined. In the present embodiment, the recording head 7 and the base plate 23 are fixed by screws 28. Specifically, a flange portion 29 formed on a holder 27 (see FIG. 4) constituting the lower part of the recording head 7 is fixed to the edge of the base through hole 26 of the base plate 23 by screws 28. Further, in the present embodiment, two rows of recording heads 7 in which three recording heads 7 are arranged in the longitudinal direction are provided.

  As shown in FIGS. 4 to 6, the recording head 7 in this embodiment includes a holder 27 that holds the unit head 32, an intermediate flow path member 33 that supplies ink to the unit head 32, and a pressure adjustment valve 58 and the like inside. The formed valve unit 34, a plurality of cover members (specifically, a first outer cover 35, a first inner cover 36, a second outer cover 37, a second inner cover 38) and the like are provided. ing. Further, as shown in FIG. 4, a liquid introduction port 24, an air release port 30, and a connector 25 are projected from the upper surface of the recording head 7. The liquid introduction port 24 and the connector 25 are connected to the supply member 22 as described above, while the atmosphere release port 30 is open to the atmosphere without being connected to the supply member 22. In the present embodiment, the liquid inlet 24, the atmosphere opening 30, and the connector 25 are formed in the first outer cover 35.

  As shown in FIGS. 6 and 7, the first outer cover 35 and the first inner cover 36 are plate-like members that cover the upper part of the valve unit 34. Specifically, the first inner cover 36 is a cover member that covers the upper surface and the upper side surface of the valve unit 34, and the first outer cover 35 is further outside (that is, the first inner cover 36). It is a cover member that covers the outer side. The first inner cover 36 in the present embodiment is attached to the valve unit 34 without a substantial gap. Further, as shown in FIG. 6, a first cover opening 39 is opened at a position corresponding to an opening at the upper end of a gas path 53 (described later) on the upper surface of the first inner cover 36. Further, as shown in FIG. 7, the second cover opening 40 is opened at a position corresponding to the upper end opening of the upper flow path 60 (described later) on the upper surface portion of the first inner cover 36.

  The first outer cover 35 is arranged with a space so that a space is formed between the first outer cover 35 and the first inner cover 36. In the present embodiment, a space is formed between the upper surface portion of the first outer cover 35 and the upper surface portion of the first inner cover 36, while the side surface portion of the first outer cover 35 and the first inner portion are formed. The cover 36 is attached so as not to be substantially spaced from the side surface portion. Thereby, a substrate arrangement space 42 and an upper space 43 are formed between the first outer cover 35 and the first inner cover 36. The board placement space 42 and the upper space 43 are partitioned by a partition plate 44 extending downward from the upper surface portion of the first outer cover 35.

  The board arrangement space 42 communicates with the connector space 46 inside the portion that becomes the connector 25 extending upward from the upper surface of the first outer cover 35, and is a space in which the first relay board 45 is arranged. is there. The first relay board 45 is accommodated in the connector space 46 and the board placement space 42 with the terminals 47 exposed in the openings of the connector space 46. As shown in FIG. 6, the bottom surface portion of the upper space 43 communicates with the gas path 53 through the first cover opening 39. Further, the upper surface portion of the upper space 43 is communicated with the atmosphere via the atmosphere opening port 30 (specifically, the space inside the atmosphere opening port 30) protruding from the upper surface portion of the first outer cover 35. ing. Further, as shown in FIG. 7, the upper space 43 protrudes downward from a portion corresponding to the liquid inlet 24 of the first outer cover 35 (that is, opposite to the liquid inlet 24). An upper insertion channel 48 is disposed. The upper insertion channel 48 has its tip inserted into the valve unit 34 (specifically, the upper channel 60 of the valve unit 34), and ink flowing from the liquid introduction port 24 enters the upper channel 60 of the valve unit 34. This is the supply part. A seal member 50 is disposed between the outer periphery of the distal end portion of the upper insertion channel 48 and the inner periphery of the upper channel 60. As a result, the upper insertion channel 48 and the upper channel 60 are in fluid-tight communication. The first outer cover 35 is fixed to the second outer cover 37 with screws or the like, and the first inner cover 36 is fixed to the second inner cover 38 with screws or the like.

  As shown in FIGS. 6 and 7, the second outer cover 37 and the second inner cover 38 are plate-like members that cover the lower part of the valve unit 34. The second outer cover 37 is a wall member that stands up from the outer peripheral edge on the upper surface of the holder 27 and is fixed to the outer peripheral edge with an adhesive or the like. The second inner cover 38 in the present embodiment is attached to the upper surface of the holder 27 with a space therebetween, and is attached to the valve unit 34 without a substantial gap. Therefore, a lower space 52 in which the intermediate flow path member 33 is disposed is formed between the lower surface portion of the second inner cover 38 and the upper surface of the holder 27. The lower space 52 is substantially sealed by, for example, filling a filler or the like between the second outer cover 37 and the second inner cover 38. Further, as shown in FIG. 6, the lower space 52 communicates with a first gas connection path 51 (corresponding to the first connection path in the present invention) that penetrates the second inner cover 38. This gas connection path 51 is connected to a gas path 53 (specifically, a second gas connection path 54 to be described later). The first gas connection path 51 in the present embodiment extends upward from the lower surface portion of the second inner cover 38. Further, as shown in FIG. 7, the lower insertion channel 49 is inserted into a position corresponding to a lower insertion channel 49 (described later) in the lower surface portion (in other words, the bottom surface portion) of the second inner cover 38. A third cover opening 41 is opened.

  The valve unit 34 (corresponding to the second member in the present invention) is a unit sandwiched between the first inner cover 36 and the second inner cover 38. Inside the valve unit 34 are a gas path 53 that opens the lower space 52 to the atmosphere, and a series of flow paths that adjust the supply pressure of ink supplied from the ink tank 3 to the unit head 32 (second in the present invention). Equivalent to the liquid path). Specifically, as shown in FIG. 6, the gas path 53 is formed in a state of penetrating in the vertical direction at a position corresponding to the first cover opening 39. In other words, the upper end of the gas path 53 corresponds to the position corresponding to the first cover opening 39 (specifically, the upper surface of the valve unit 34 (that is, the surface opposite to the lower surface of the valve unit 34 facing the lower space 52). ) At a position corresponding to the first cover opening 39) and communicates with the upper space 43 via the first cover opening 39. The opening at the upper end of the gas path 53 corresponds to the opening in the present invention. Further, the lower end portion of the gas path 53 is a second gas connection path 54 (corresponding to the second connection path in the present invention) into which the first gas connection path 51 is inserted. The first gas connection path 51 and the second gas connection path 54 are airtightly connected via a seal member 55 (a kind of elastic member in the present invention). The connection structure between the first gas connection path 51 and the second gas connection path 54 will be described in detail later.

  As shown in FIG. 7, the valve unit 34 is provided with a pressure adjusting portion 59 having a filter chamber 57 in which a filter 56 is disposed and a pressure adjusting valve 58. The filter chamber 57 is a chamber into which ink sent from the supply member 22 through the liquid inlet 24 and the upper insertion flow path 48 is introduced. The filter chamber 57 and the upper insertion channel 48 are connected via an upper channel 60. Further, a filter 56 is disposed at a boundary portion between the filter chamber 57 and the pressure adjusting portion 59 (specifically, the valve accommodating chamber 61). By this filter 56, it can suppress that the foreign material etc. which have flowed from the upstream side flow to the downstream side. The pressure adjusting unit 59 seals the valve accommodating chamber 61 in which the pressure regulating valve 58 is disposed, the pressure regulating chamber 62 communicating with the valve accommodating chamber 61, and the opening on one side of the pressure regulating chamber 62. And a pressure receiving member 63 arranged in the above. The wall partitioning the pressure regulating chamber 62 and the valve accommodating chamber 61 is provided with an inlet 64 that allows the valve accommodating chamber 61 and the pressure regulating chamber 62 to communicate with each other. It functions as a valve seat. The pressure adjustment valve 58 is urged toward the pressure adjustment chamber 62 by an urging member 68 such as a coil spring, and the shaft portion is inserted into the pressure adjustment chamber 62 via the inflow port 64.

  The opening of the pressure adjusting chamber 62 is sealed by a diaphragm-shaped pressure receiving member 63 and partitioned from the atmospheric pressure space 69. Note that the atmospheric pressure space 69 is a space outside the pressure adjustment chamber 62. For example, a path (a path different from the gas path 53) formed in the first outer cover 35, the first inner cover 36, or the like is used. Through the space outside the recording head 7, that is, open to the atmosphere. The pressure receiving member 63 includes a flexible film member 66 that elastically deforms to the inside of the pressure adjustment chamber 62 (on the valve housing chamber 61 side) when the internal pressure of the pressure adjustment chamber 62 becomes lower than a predetermined pressure. It is comprised by the operating piece 67 provided inside. The operating piece 67 is configured to be rotatable with the deformation of the film member 66 with one end portion as a fulcrum. When the pressure receiving member 63 is elastically deformed inward and is pressed by the pressure receiving member 63 and the pressure adjusting valve 58 moves toward the filter chamber 57 against the urging force of the urging member 68, the pressure adjusting valve 58 causes the flow. The state changes from a closed state where the inlet 64 is closed to an open state where the inflow of ink is allowed from the valve storage chamber 61 side to the pressure adjustment chamber 62 side through the inflow port 64. In addition, a lower flow path 65 communicates with the bottom of the pressure adjusting chamber 62 on the downstream side of the inlet 64. The lower end of the lower flow path 65 opens at a position (specifically, a position shifted in the nozzle row direction) different from the opening at the lower end of the gas path 53 (that is, the opening of the second gas connection path 54). In addition, the first gas connection path 51 and the second gas connection path 54 are connected to the lower insertion flow path 49 at a position different from the connection location. In the present embodiment, the lower channel 65 and the lower insertion channel 49 are connected by inserting the lower insertion channel 49 into the lower end of the lower channel 65. A seal member 50 is disposed between the outer periphery of the distal end portion of the lower insertion channel 49 and the inner periphery of the lower channel 65. As a result, the lower insertion flow path 49 and the lower flow path 65 are in fluid-tight communication. The lower insertion channel 49 corresponds to the third connection path in the present invention, and the lower end of the lower channel 65 corresponds to the fourth connection path in the present invention.

  The intermediate flow path member 33 is a member that is disposed on the upper surface of the holder 27 and is held between the upper surface of the holder 27 and the lower surface portion of the second inner cover 38 (that is, in the lower space 52). The intermediate flow path member 33 is inserted into the valve unit 34 and distributes the ink introduced through the lower insertion flow path 49 to the respective unit heads 32 through which the ink from the valve unit 34 is introduced. And a distribution channel 70. The lower insertion flow path 49 protrudes from the upper surface of the intermediate flow path member 33 toward the valve unit 34 at a position different from the first gas connection path 51 (specifically, a position shifted in the nozzle row direction). And is inserted into the lower flow path 65 as described above. The distribution channel 70 is a channel whose one end (upstream side) communicates with the lower insertion channel 49 and whose other end (downstream side) is connected to the in-holder channel 77. The distribution flow path 70 in this embodiment is branched into four according to the number of unit heads 32.

  The holder 27 is a box-shaped member made of synthetic resin or the like that forms the lower part of the recording head 7. Inside the holder 27, a head accommodating space 73 for accommodating the unit head 32 is formed. In the present embodiment, as shown in FIG. 5, since one recording head 7 includes four unit heads 32, four head accommodating spaces 73 are formed correspondingly. A fixing plate 74 is attached to the lower surface of the holder 27 so as to close the opening on the lower surface side of the head accommodating space 73. The fixing plate 74 is fixed to the lower surface of the holder 27 and the lower surface of the unit head 32 using an adhesive or the like in a state where the unit head 32 is accommodated in the head accommodating space 73. The head accommodation space 73 is sealed by the fixing plate 74. The fixed plate 74 is formed with a fixed plate opening 75 through which the nozzle 86 of each unit head 32 is exposed.

  Further, as shown in FIGS. 6 and 7, a wiring member arrangement space 76 and a flow path 77 in the holder penetrating from the head accommodation space 73 to the upper surface of the holder 27 are formed in the holder 27 for each head accommodation space 73. Has been. As shown in FIG. 6, the wiring member arrangement space 76 is a space that connects the head accommodating space 73 and the space above the holder 27 (that is, the lower space 52). The second wiring member 80 extending from the unit head 32 is connected to a second relay substrate 78 disposed between the holder 27 and the intermediate flow path member 33 through the wiring member arrangement space 76. As shown in FIG. 7, the in-holder channel 77 includes a liquid introduction channel 84 (see FIG. 8) of the unit head 32 housed in the head housing space 73 and a distribution channel 70 in the intermediate channel member 33. It is the flow path to connect. That is, the lower end of the in-holder flow path 77 is liquid-tightly connected to the liquid introduction path 84, and the upper end of the in-holder flow path 77 is liquid-tightly connected to the distribution flow path 70.

  As shown in FIG. 6, the first relay board 45 and the second relay board 78 described above are connected by a first wiring member 79 such as an FPC (flexible printed circuit board). The first wiring member 79 passes through the gap between the first outer cover 35 and the first inner cover 36 and the gap between the second outer cover 37 and the second inner cover 38. To the lower space 52. The upper end of the first wiring member 79 is connected to the first relay board 45 in the board placement space 42, and the lower end is connected to the second relay board 78 in the lower space 52. Of the gap where the first wiring member 79 is disposed, at least a part of the gap between the second outer cover 37 and the second inner cover 38 is inserted into the first wiring member 79. It can be filled with a filler or the like.

  Next, the unit head 32 in this embodiment will be described in detail. FIG. 8 is a cross-sectional view of the main part of the unit head 32. As shown in FIG. 8, the unit head 32 in this embodiment is a state in which a nozzle plate 85, a flow path substrate 90, a piezoelectric element 93 (a kind of actuator), a sealing plate 94, a compliance substrate 98, and the like are laminated. Thus, the head case 82 is attached.

  The flow path substrate 90 is a silicon substrate (for example, a silicon single crystal substrate) that is long along the nozzle row direction. As shown in FIG. 8, two long communication portions 88 are formed in the flow path substrate 90 along the longitudinal direction of the flow path substrate 90. The communication portion 88 communicates with the through portion 95 of the sealing plate 94 to form a common liquid chamber 87. A plurality of pressure chambers 91 are arranged in parallel along the nozzle row direction in a region sandwiched between the two communicating portions 88 of the flow path substrate 90. The rows of pressure chambers 91 are formed in two rows corresponding to the two communicating portions 88. Each pressure chamber 91 communicates with the communication portion 88 via a supply path 89 formed with a narrower width than the pressure chamber 91.

  A nozzle plate 85 is fixed to the lower surface (surface opposite to the sealing plate 94) of the flow path substrate 90 via an adhesive or the like. The nozzle plate 85 is made of a silicon substrate (for example, a silicon single crystal substrate), and a plurality of nozzles 86 communicating with the pressure chamber 91 are formed in each pressure chamber 91. That is, a plurality of nozzles 86 are provided in the nozzle plate 85 in a straight line shape (in other words, in a row) along the longitudinal direction of the nozzle plate 85. The plurality of nozzles 86 arranged side by side are provided at equal intervals at a pitch corresponding to the dot formation density from the nozzle 86 on one end side to the nozzle 86 on the other end side. In the present embodiment, two rows of nozzles 86 spaced from each other are formed in two rows corresponding to the rows of pressure chambers 91 formed in two rows.

A diaphragm 92 is laminated on the upper surface of the flow path substrate 90 (the surface opposite to the nozzle plate 85). The vibration plate 92 includes, for example, an elastic film made of silicon dioxide (SiO ₂ ) formed on the upper surface of the flow path substrate 90 (that is, the surface opposite to the sealing plate 94 side), and the elastic film And an insulating film made of zirconium dioxide (ZrO ₂ ). The diaphragm 92 seals the upper opening of the space to be the pressure chamber 91. In other words, the upper surface of the pressure chamber 91 is partitioned by the diaphragm 92. A portion of the diaphragm 92 corresponding to the pressure chamber 91 (specifically, an upper opening of the pressure chamber 91) functions as a displacement portion that is displaced in a direction away from or near to the nozzle 86 as the piezoelectric element 93 is bent and deformed. To do. A region corresponding to the communication portion 88 in the diaphragm 92 is an opening from which the diaphragm 92 is removed.

  Piezoelectric elements 93 are stacked in regions corresponding to the pressure chambers 91 on the upper surface of the diaphragm 92. The piezoelectric element 93 in the present embodiment is a so-called bending mode piezoelectric element. A plurality of piezoelectric elements 93 are arranged in parallel along the nozzle row direction corresponding to each nozzle 86. Each piezoelectric element 93 is formed by, for example, sequentially laminating a lower electrode layer serving as an individual electrode, a piezoelectric layer, and an upper electrode layer serving as a common electrode in order from the vibration plate 92. Note that the lower electrode layer can be a common electrode and the upper electrode layer can be an individual electrode depending on the convenience of the drive circuit and wiring. When an electric field corresponding to the potential difference between the two electrodes is applied between the lower electrode layer and the upper electrode layer, the piezoelectric element 93 configured as described above bends and deforms in a direction away from or close to the nozzle 86. As a result, the volume of the pressure chamber 91 changes, and the pressure in the ink in the pressure chamber 91 changes. The unit head 32 ejects ink from the nozzles 86 by utilizing the pressure fluctuation.

  A sealing plate 94 made of a silicon substrate (for example, a silicon single crystal substrate) is joined to the upper surface of the vibration plate 92. The sealing plate 94 is formed with a penetrating portion 95 serving as a common liquid chamber 87 and a piezoelectric element array accommodating space 96 isolated from the penetrating portion 95. The penetrating portion 95 is formed in a state penetrating in the thickness direction at a position corresponding to the communicating portion 88. The penetrating portion 95 in the present embodiment is formed long along the nozzle row direction. Note that the width (specifically, the dimension in the direction orthogonal to the nozzle row direction) of the upper portion of the penetrating portion 95 (in other words, the portion on the head case 82 side) is lower than the penetrating portion 95 (in other words, on the flow path substrate 90 side The width is larger than the width of the portion. In the present embodiment, the inner portion of the upper portion of the penetrating portion 95 (that is, the center side in the direction orthogonal to the nozzle row direction) is not penetrated in the plate thickness direction from the upper surface of the sealing plate 94. It is formed in a state of being depressed halfway in the thickness direction. A liquid introduction path 84 to be described later is communicated with a portion recessed from the upper surface of the through portion 95. Further, two penetrating portions 95 in the present embodiment are provided corresponding to the two communicating portions 88. The lower end of each penetrating part 95 communicates with the communicating part 88 to constitute a common liquid chamber 87.

  The piezoelectric element row accommodating spaces 96 are formed in two rows corresponding to the rows of piezoelectric elements 93 formed in two rows. The piezoelectric element row accommodating space 96 is formed long along the nozzle row direction. In addition, the piezoelectric element array accommodating space 96 is formed in a state of being recessed from the lower surface of the sealing plate 94 to the middle in the thickness direction so as not to inhibit the displacement of the piezoelectric element 93. Further, a connection space 97 is formed between the two piezoelectric element array accommodating spaces 96 in which the sealing plate 94 is removed in the thickness direction. The connection space 97 communicates with an insertion space 83 to be described later, and an end portion of a second wiring member 80 such as an FPC (flexible printed circuit board) inserted into the insertion space 83 is disposed therein. The end portion of the second wiring member 80 is connected to a lead wiring terminal (not shown) extending from each piezoelectric element 93 in the connection space 97. The piezoelectric element array accommodating space 96 is opened to the space outside the unit head 32, that is, the head accommodating space 73 through an air opening path (not shown) in which the flow path resistance is increased as much as possible.

  A compliance substrate 98 is bonded to the upper surface of the sealing plate 94. The compliance substrate 98 is a substrate that seals the upper surface of the communication portion 88 to partition the common liquid chamber 87, and includes a flexible sealing film 100 and a fixed substrate 99 made of a hard member such as metal. It is made up of layers. In the present embodiment, the compliance substrate 98 is bonded to the upper surface of the sealing plate 94 with the sealing film 100 disposed below (that is, on the sealing plate 94 side). A position corresponding to the insertion space 83 and a position corresponding to the liquid introduction path 84 in the compliance substrate 98 are openings penetrating in the thickness direction. In addition, in the region of the compliance substrate 98 that faces the common liquid chamber 87, the region other than the periphery of the liquid inlet 24 is only the sealing film 100 from which the fixed substrate 99 is removed. The portion consisting only of the sealing film 100 functions as a compliance portion that absorbs pressure fluctuations of the ink in the common liquid chamber 87.

  A head case 82 is joined to the upper surface of the compliance substrate 98. The head case 82 in this embodiment is a box-shaped member made of synthetic resin. An insertion space 83 that is a long space along the nozzle row direction is formed at the center of the head case 82. The insertion space 83 is a space through which the second wiring member 80 is inserted, and is formed in a state of penetrating the head case 82 in the plate thickness direction. In other words, the insertion space 83 opens to the upper surface of the unit head 32 and communicates with the head accommodation space 73 and the wiring member arrangement space 76. In addition, a liquid introduction path 84 connected to the in-holder flow path 77 is formed inside the head case 82. The lower end of the liquid introduction path 84 is connected to the common liquid chamber 87 (specifically, the through portion 95). Furthermore, a compliance space 101 having a depth that does not hinder flexible deformation of the sealing film 100 is formed in a state of being recessed from the lower surface of the lower surface of the head case 82 corresponding to the common liquid chamber 87. . The compliance space 101 is opened to the space outside the unit head 32, that is, the head accommodating space 73, through an air opening path (not shown) in which the flow path resistance is increased as much as possible.

  As described above, the space in the unit head 32, that is, the connection space 97 and the insertion space 83 in which the second wiring member 80 is disposed, the piezoelectric element array accommodation space 96, and the compliance space 101 are included in the head accommodation. It communicates with the space 73. The head accommodating space 73 is in communication with the lower space 52 via the wiring member arrangement space 76. A series of spaces including the space in the unit head 32, the head accommodating space 73, the wiring member arrangement space 76, and the lower space 52 correspond to the space in the present invention. Further, this series of spaces is kept airtight except for a portion communicating with the first gas connection path 51. Further, the lower space 52 communicates with the gas path 53 in an airtight manner by the connection of the first gas connection path 51 and the second gas connection path 54. The gas path 53 communicates with the atmosphere via the upper space 43 and the atmosphere opening 30. That is, a series of spaces including the space in the unit head 32, the head accommodating space 73, the wiring member arrangement space 76, and the lower space 52 are open to the atmosphere.

  On the other hand, ink from the ink tank 3 is introduced into the valve unit 34 via the liquid supply tube 8, the liquid flow path in the supply member 22, the liquid inlet 24, and the upper insertion flow path 48. In addition, the some flow path which consists of any one flow path among these flow paths formed in the member outside these valve units 34, or these combination is equivalent to the external flow path in this invention. Ink introduced into the valve unit 34 is supplied from the upper flow path 60, the filter chamber 57, the valve storage chamber 61, the inlet 64, the pressure adjustment chamber 62, and the lower flow path 65 when the pressure adjustment valve 58 is open. It is introduced into the intermediate flow path member 33 through a series of flow paths in the valve unit 34. A series of flow paths in the valve unit 34 corresponds to the second liquid path in the present invention. Further, the ink introduced into the intermediate flow path member 33 flows through the lower insertion flow path 49 and the distribution flow path 70 in the intermediate flow path member 33 and the flow path in the unit head 32 via the in-holder flow path 77. To be supplied. Then, the ink introduced into the unit head 32 is supplied to the nozzle 86 via the flow path in the unit head 32, that is, the liquid introduction path 84, the common liquid chamber 87, the supply path 89, and the pressure chamber 91. Is done. A series of flow paths (in other words, liquid paths) extending from the flow path in the unit head 32 to the nozzle 86 including the flow path in the holder 77, the distribution flow path 70, and the lower insertion flow path 49 are provided in the present invention. This corresponds to the first liquid path. A group of members including the second outer cover 37, the second inner cover 38, the intermediate flow path member 33, the holder 27, the unit head 32, and the fixing plate 74 corresponds to the first member in the present invention.

  Here, the valve unit 34 is sandwiched between the first inner cover 36 and the second inner cover 38 without using an adhesive or the like. Therefore, the valve unit 34 can be easily detached from the second inner cover 38 by removing the first inner cover 36 from the second inner cover 38. And when attaching the valve unit 34 again, the lower insertion flow path 49 and the lower flow path 65 are connected, and the first gas connection path 51 and the second gas connection path 54 are connected. The valve unit 34 may be disposed on the second inner cover 38 and the first inner cover 36 may be fixed to the second inner cover 38. In short, the valve unit 34 is detachably attached to the second inner cover 38. In a state where the valve unit 34 is attached to the second inner cover 38, that is, in a state where the valve unit 34 is sandwiched between the first inner cover 36 and the second inner cover 38, the first gas connection path 51 and the 2nd gas connection path 54 are connected airtightly. Further, the upper insertion channel 48 and the upper channel 60 are liquid-tightly connected, and the lower insertion channel 49 and the lower channel 65 are liquid-tightly connected. In addition, the fixing method of the valve unit 34 is not restricted to what was illustrated by this embodiment. For example, the valve unit 34 may be attached to the second inner cover 38 by locking a locking portion or screwing a screw. In short, any fixing method may be used as long as the valve unit 34 can be detachably attached to the second inner cover 38.

  Next, the connection location between the first gas connection path 51 and the second gas connection path 54 will be described in detail. FIG. 9 is an enlarged cross-sectional view of a connection location between the first gas connection path 51 of the second inner cover 38 and the second gas connection path 54 of the valve unit 34. As described above, the first gas connection path 51 is a gas path (passage) extending upward from the second inner cover 38, and the first gas connection path 51 has a protrusion 102 protruding from the second inner cover 38. It is formed inside. Specifically, the protruding portion 102 is formed in a cylindrical shape, and the first gas connection path 51 is formed so as to penetrate the second inner cover 38 in the protruding portion 102. That is, one end of the first gas connection path 51 is opened at the tip of the protruding portion 102, and the other end is opened at the lower surface of the second inner cover 38 (surface on the lower space 52 side). In addition, a flange 103 is formed in the first gas connection path 51 so as to protrude inward from the inner wall surface that defines the first gas connection path 51. The flange 103 has a flow passage area (cross-sectional area) of the first gas connection path 51 in the middle of the first gas connection path 51 in the vertical direction (that is, the extending direction of the first gas connection path 51). ). The first gas connection path 51 is divided into two spaces of an upper connection path 104 and a lower connection path 105 by the flange 103. The upper connection path 104 and the lower connection path 105 are connected to each other through a communication opening 106 formed in the gap of the flange 103.

  The communication opening 106 is a space having a smaller diameter than the upper connection path 104 and the lower connection path 105, which penetrates the flange portion 103 in the vertical direction. The communication opening 106 in the present embodiment is formed in a circular shape and concentric with the upper connection path 104 and the lower connection path 105 in plan view. The communication opening 106 is preferably formed to have a diameter that allows the liquid to form a meniscus when a liquid such as ink flows into the communication opening 106, for example, a diameter of 0.2 mm or less. Has been. Note that the number of communication openings 106 formed in the flange 103 is not limited to one, and two or more may be formed. That is, as long as the flow area (cross-sectional area) of the first gas connection path 51 can be reduced, the shape of the flange portion 103 and the communication opening 106 may be any shape.

  The second gas connection path 54 is a portion that forms the lower end of the gas path 53 of the valve unit 34. The inner diameter of the second gas connection path 54 is formed to be larger (that is, larger) than the outer shape of the protrusion 102 so that the protrusion 102 can be inserted. Then, the first gas connection path 51 and the second gas connection path 54 are connected by inserting the protruding portion 102 into the second gas connection path 54. The inner diameter of the second gas connection path 54 in the present embodiment is formed larger than the inner diameter of the other part of the gas path 53. Note that the inner diameter of the second gas connection path 54 and the inner diameter of the other part of the gas path 53 can be formed to the same size. An annular seal member 55 is disposed between the protruding portion 102 and the inner wall surface of the second gas connection path 54. The seal member 55 in this embodiment is attached to the inner wall surface of the second gas connection path 54. Specifically, a mounting piece 107 extending downward is formed on the outer peripheral portion of the seal member 55, and the mounting space 107 is formed on the inner peripheral surface of the second gas connection path 54. The seal member 55 is attached to the inner peripheral surface of the second gas connection path 54 by being fitted into the second gas connection path 54. Note that the inner diameter of the seal member 55 is smaller than the outer diameter of the protrusion 102 in a state where the protrusion 102 is not inserted into the seal member 55. For this reason, when the protrusion 102 is inserted into the seal member 55, the seal member 55 is deformed, and the first gas connection path 51 and the second gas connection path 54 are hermetically sealed via the seal member 55. Communicate.

  As described above, since the first gas connection path 51 and the second gas connection path 54 are airtightly connected, the recording head 7 of the present invention can suppress the liquid from entering the space through this connection point. . Further, since the lower space 52 is opened to the atmosphere via the gas path 53 of the valve unit 34, the distance from the upper space 43 to the lower space 52 becomes longer, and as a result, the distance from the atmosphere to the lower space 52 becomes longer. . As a result, liquid such as ink that has entered the upper space 43 through the air opening 30, moisture dripping due to condensation or the like, or cleaning liquid remaining when the valve unit 34 is cleaned is opened at the upper end of the gas path 53. Even if it enters from the part, it is possible to suppress the liquid from reaching the space below the lower space 52. As a result, it is possible to prevent the second relay substrate 78 disposed in the lower space 52 and the piezoelectric elements 93 in the piezoelectric element array accommodating space 96 from being destroyed or damaged. Furthermore, in this embodiment, since the flange 103 is formed inside the first gas connection path 51, the liquid as described above enters the first gas connection path 51 through the gas path 53. Even if it does, it can suppress further that a liquid reaches | attains the lower space 52 by the collar part 103. FIG. In particular, if the diameter of the communication opening 106 formed in the gap between the flanges 103 is set to a size that allows the liquid to form a meniscus, the entry of the liquid into the lower space 52 can be further suppressed. Since the valve unit 34 is detachably attached to the second inner cover 38, for example, when replacing the valve unit 34 in repair or the like, the valve unit 34 can be easily replaced.

  Further, the first gas connection path 51 is formed in the protrusion 102, and the protrusion 102 is inserted into the second gas connection path 54, so that the first gas connection path 51 and the second gas connection are connected. Connection to the path 54 is facilitated. In addition, the positioning of the valve unit 34 with respect to the second inner cover 38 is facilitated. Furthermore, since the first gas connection path 51 and the second gas connection path 54 are connected via the seal member 55, the connection location between the first gas connection path 51 and the second gas connection path 54. The airtightness can be improved. In particular, since the seal member 55 is attached to the inner wall surface of the second gas connection path 54, the protrusion 102 is connected to the second gas connection path as compared with the case where the seal member 55 is disposed around the protrusion 102. 54 becomes easy to insert. That is, when the seal member is disposed around the protrusion, the outer peripheral surface of the seal member having a relatively large area and the inner wall surface of the second gas connection path rub against each other, so that the frictional force (resistance force) increases. On the other hand, when the seal member 55 is disposed on the inner wall surface of the second gas connection path 54 as in the present embodiment, the inner peripheral surface of the seal member 55 having a relatively small area and the outer peripheral surface of the protruding portion 102 rub against each other. , The frictional force becomes smaller. In short, the frictional force received from the seal member 55 when the protrusion 102 is inserted into the second gas connection path 54 can be reduced. Thereby, the connection of the 1st gas connection path 51 and the 2nd gas connection path 54 becomes still easier.

  Furthermore, since the lower end of the lower flow path 65 and the lower insertion flow path 49 are connected at a position different from the connection location between the first gas connection path 51 and the second gas connection path 54, the second internal Because there are at least two or more connection points between the lower portion (that is, the first member) of the recording head 7 including the cover 38, the intermediate flow path member 33, and the like and the valve unit 34 (that is, the second member). The position difference between the valve unit 34 and the member composed of the second inner cover 38, the intermediate flow path member 33, and the like is difficult to occur. Further, since the upper end of the gas path 53 opens to a position deviated from the lower space 52 side (in this embodiment, the upper surface of the valve unit 34), it becomes easy to inspect the airtightness described later through the opening. . Specifically, since the atmosphere opening 30 that communicates with the opening can be provided, it becomes easy to connect an airtight inspection device to be described later to the atmosphere opening 30. Furthermore, since the lower space 52 can be opened to the atmosphere at an arbitrary position via the gas path 53 of the valve unit 34, the degree of freedom in design increases.

  Note that the first gas connection channel 51 as shown in FIG. 9 is also connected at the connection point between the upper insertion channel 48 and the upper channel 60 and at the connection point between the lower insertion channel 49 and the lower channel 65. A configuration similar to that of the connection portion with the second gas connection path 54 can be adopted. That is, the annular seal member 50 is attached to the inner wall surface of the upper flow path 60, and the upper insertion flow path 48 protruding from the first outer cover 35 is inserted into the seal member 50, so that the upper insertion flow path 48 and the upper flow path A configuration for connecting the path 60 can be employed. Further, it is possible to adopt a configuration in which the annular seal member 50 is attached to the inner wall surface of the lower flow path 65 and the lower insertion flow path 49 protruding from the intermediate flow path member 33 is inserted into the seal member 50 and connected. In this case, unlike the first gas connection channel 51, the flange 103 is not formed inside the upper insertion channel 48 and the lower insertion channel 49.

  Next, a method for inspecting the recording head 7 performed when the recording head 7 described above is manufactured will be described. FIG. 10 is a flowchart for explaining the flow of the inspection method of the recording head 7. First, the second outer cover 37, the second inner cover 38, the intermediate flow path member 33, the holder 27, the unit head 32, the fixing plate 74, and the like are assembled, and the lower part of the recording head 7 is produced. Next, in the connecting step, the valve unit 34 is attached to the lower part of the created recording head 7 (step S1). That is, the protrusion 102 is inserted into the second gas connection path 54 to connect the first gas connection path 51 and the second gas connection path 54, and the lower flow path 65 and the lower insertion flow path 49 are connected to each other. In the connected state, the first outer cover 35 and the first inner cover 36 are fixed to the second outer cover 37 and the second inner cover 38, so that the valve unit with respect to the lower part of the recording head 7. 34 is fixed. Next, in this state, in the cleaning process, the cleaning liquid is introduced into the liquid inlet 24 without introducing the cleaning liquid from the atmosphere opening port 30, that is, without introducing the cleaning liquid from the opening at the upper end of the gas path 53. (Step S2). For example, a cleaning device is connected to the liquid inlet 24 and the cleaning liquid is introduced into the recording head 7 from the cleaning device. As a result, the cleaning liquid is passed through the liquid channel in the recording head 7 from the liquid inlet 24 to the nozzle 86, and the liquid channel is cleaned. When the cleaning liquid is passed through the liquid channel for a predetermined time to clean the liquid channel, the liquid passing is terminated and the recording head 7 is dried. Finally, in a state in which the first gas connection path 51 and the second gas connection path 54 are connected, a fluid (for example, air) is passed through the opening at the upper end of the gas path 53 from the atmosphere opening port 30 in the airtightness inspection process. To check the airtightness (step S3). For example, an airtight inspection device including a pump that sends air to the atmosphere opening 30 is connected, and air is introduced into the recording head 7 from the airtight inspection device. Then, after inspecting whether air has leaked to the outside of the recording head 7, the inspection is terminated.

  In this way, airtightness inspection can be performed by introducing a fluid such as air from the atmosphere opening 30, so that airtightness inspection becomes easy. In addition, since the cleaning liquid is not introduced from the air opening 30 in the cleaning process, the liquid can be prevented from reaching the space below the lower space 52. As a result, it is possible to further prevent the second relay substrate 78 disposed in the lower space 52, the piezoelectric elements 93 in the piezoelectric element array housing space 96, and the like from being destroyed or soiled.

  By the way, in 1st Embodiment mentioned above, the 1st gas connection path 51 is inserted in the 2nd gas connection path 54, and the 1st gas connection path 51 and the 2nd gas connection path 54 connect. However, it is not limited to this. For example, a configuration may be adopted in which the second gas connection path is inserted into the first gas connection path and the first gas connection path and the second gas connection path are connected. That is, a protrusion may be provided below the valve unit, a second gas connection path may be formed in the protrusion, and a first gas connection path into which the protrusion is inserted may be provided in the second inner cover. . When comprised in this way, a sealing member is attached to the inner wall face of the 1st gas connection path in which a protrusion part is inserted. In this case, the protruding portion may penetrate the second inner cover, and the tip portion may be inserted into the lower space. In short, as long as the first gas connection path and the second gas connection path are hermetically connected via the seal member, the second gas connection path and the lower space may be in direct communication.

  In the first embodiment described above, the protruding portion 102 is formed in a cylindrical shape, but is not limited thereto. The protrusion 102 in the second embodiment shown in FIG. 11 and the protrusion 102 in the third embodiment shown in FIG. 12 are formed in a needle shape that tapers toward the tip.

  Specifically, as shown in FIG. 11, the protruding portion 102 in the second embodiment is inserted into the second gas connection path 54, and the tip portion on the upper side (back side) of the seal member 55. 109 is formed to be tapered (in other words, to have a reduced diameter). In addition, the first gas connection path 51 in the present embodiment includes a lower connection path 105 below the collar part 103, an upper connection path 104 above the collar part 103, and a tip connection path that penetrates the tip part 109. 110. The tip connection path 110 is a portion having a smaller diameter than the lower connection path 105 and the upper connection path 104, and extends along the vertical direction (that is, the protruding direction of the protruding portion 102). The tip connection path 110 is opened at the tip of the tip portion 109. Thus, since the protrusion part 102 was formed in the taper shape, it becomes easy to insert the 1st gas connection path 51 in the seal member 55. FIG. As a result, the connection between the first gas connection path 51 and the second gas connection path 54 is further facilitated. In addition, since the first gas connection path 51 is opened at the tip of the protruding portion 102, it becomes difficult for the liquid to enter the inside of the first gas connection path 51. That is, as the broken line shown in FIG. 11, the liquid flows along the inclination of the tip portion 109, so that it is difficult to enter the tip connection path 110. Note that the upper end side (that is, the back side) of the second gas connection path 54 is reduced in diameter according to the shape of the protruding portion 102. Other configurations are the same as those of the first embodiment described above, and thus description thereof is omitted.

  In addition, as shown in FIG. 12, the first gas connection path 51 in the third embodiment is opened in a direction intersecting the protruding direction of the protruding portion 102 at the tip portion 109 of the protruding portion 102. . Specifically, the first gas connection path 51 in the present embodiment includes a lower connection path 105 that is lower than the flange 103, an upper connection path 104 that is higher than the flange 103, and the slope side of the tip portion 109. And a tip connection path 110 that opens to the front. That is, the tip connection path 110 in the present embodiment extends from the upper end of the upper connection path 104 toward the tip of the protruding portion 102, is bent in the middle, and opens to the slope of the tip portion 109. As described above, by opening the distal end connection path 110 on the slope side of the distal end portion, the liquid becomes more difficult to enter the first gas connection path 51. The tip connection path 110 may have any configuration as long as it opens to the side of the tip portion 109. For example, the tip connection path may be configured to extend obliquely from the upper end of the upper connection path toward the slope of the tip portion. Other configurations are the same as those of the above-described second embodiment, and thus description thereof is omitted.

  By the way, in each of the above-described embodiments, each space in the unit head 32 (that is, the connection space 97 and the insertion space 83 in which the second wiring member 80 is disposed, the piezoelectric element array housing space 96, and the compliance space 101). ) Is opened to the atmosphere via one gas path 53, but is not limited thereto. For example, the lower space may be divided so as to correspond to each space, and each space and each lower space communicate with each other in an airtight manner, and a gas path that communicates with each lower space may be provided. In addition, a configuration in which a part of a series of gas paths is partitioned by a flexible member may be employed. For example, in 4th Embodiment illustrated in FIGS. 13-16, it is comprised so that the pressure receiving member 63 can be pressed by the flexible member 111 which has flexibility. This will be described in detail below. FIG. 13 is a perspective view of the recording head 7 in the fourth embodiment. 14 is a sectional view taken along line AA in FIG. 13, FIG. 15 is a sectional view taken along line BB, and FIG. 16 is a sectional view taken along line CC.

  As shown in FIG. 13, in addition to the liquid introduction port 24, the air release port 30, and the connector 25, a connection port 113 projects from the upper surface of the recording head 7 in this embodiment. The connection port 113 is connected to the supply member 22 and communicates with a pressurization mechanism (not shown) through a gas path 53 in the supply member 22 (not shown). As shown in FIG. 15, an upper gas connection path 114 protruding downward from the first outer cover 35 is formed on the opposite side of the first outer cover 35 from the connection port 113. The upper gas connection path 114 is a gas path communicating with the connection port 113. The tip of the upper gas connection path 114 is inserted into the valve unit 34 via a fourth cover opening 115 formed in the upper surface portion of the first inner cover 36. The upper gas connection path 114 is airtightly connected to a pressure adjustment path 116 formed inside the valve unit 34. In addition, the connection location of the pressure adjustment path 116 and the upper gas connection path 114 is substantially the same as the connection position of the first gas connection path 51 and the second gas connection path 54 shown in FIG. Since it is a structure, description is abbreviate | omitted.

  The pressure adjustment path 116 communicates with the vertical path 117 extending in the vertical direction from the upper surface of the valve unit 34 to the middle of the lower surface side, and a part of the vertical path 117, and intersects the extending direction of the vertical path 117. A horizontal path 118 extending in the direction of the horizontal axis. The end of the horizontal path 118 opposite to the vertical path 117 is connected to a pressing space 119 facing the pressure receiving member 63 via the atmospheric pressure space 69. As shown in FIG. 16, the pressing space 119 is a space in which the opening on the atmospheric pressure space 69 side is sealed with a flexible member 111 made of a thin film made of synthetic resin, for example. That is, the flexible member 111 is a film that is disposed on the inner wall surface of the pressing space 119 and forms the inner wall surface of the pressing space 119. The flexible member 111 divides the pressing space 119 and the outer atmospheric pressure space 69. The atmospheric pressure space 69 is open to the atmosphere through a gas path (not shown). Further, as shown in FIG. 14, the gas path from the atmosphere opening 30 to the space in the unit head 32 has substantially the same configuration as that of the first embodiment, and the description thereof will be omitted. Further, as shown in FIG. 16, the liquid flow path from the liquid introduction port 24 to the nozzle 86 via the flow path in the unit head 32 has substantially the same configuration as that of the first embodiment described above. Omitted.

  Thus, in this embodiment, since the pressing space 119 and the atmospheric pressure space 69 are partitioned by the flexible member 111, the pressurizing mechanism is driven to connect the connection port 113, the upper insertion channel 48, and the pressure adjustment path. 116 and the flexible member 111 can be deformed to the outside (that is, the pressure receiving member 63 side) by sending gas (for example, air) to the pressing space 119. Then, the pressure receiving member 63 disposed in the atmospheric pressure space 69 can be pressed using the deformation of the flexible member 111. As a result, the pressure receiving member 63 is deformed inward, and the pressure adjusting valve 58 can be changed to the open state. That is, the pressure adjustment valve 58 is forcibly changed to the open state, and the ink from the ink tank 3 can be sent to the unit head 32 side.

  In this embodiment, if attention is paid to the gas path from the connection port 113 to the pressing space 119, the valve unit 34 corresponds to the first member of the present invention, and the first outer cover 35 corresponds to the first member of the present invention. It corresponds to 2 members. In this case, the pressure adjustment path 116 other than the part where the upper gas connection path 114 is inserted, and the pressing space 119 correspond to the space in the present invention, and the part where the upper gas connection path 114 of the pressure adjustment path 116 is connected. This corresponds to the first connection path in the present invention. The series of flow paths in the valve unit 34 corresponds to the first liquid path in the present invention. Furthermore, the upper gas connection path 114 corresponds to the second connection path in the present invention, and the upper insertion flow path 48 corresponds to the second liquid path in the present invention. The opening at the upper end of the connection port 113 corresponds to the opening in the present invention, and a series of paths from the upper gas connection path 114 to the opening at the upper end of the connection port 113 corresponds to the gas path in the present invention. On the other hand, if attention is paid to the gas path from the atmosphere opening 30 to the space in the unit head 32, the second outer cover 37, the second inner cover 38, the intermediate flow path member, as in the above-described embodiments. 33, the holder 27, the unit head 32, and the fixing plate 74 correspond to the first member in the present invention, and the valve unit 34 corresponds to the second member in the present invention.

  Further, in each of the above-described embodiments, the upper end of the gas path 53 is connected to the atmosphere opening 30 via the first cover opening 39 and the upper space 43, but this is not restrictive. A configuration similar to the connection point between the upper insertion channel 48 and the upper channel 60 can also be adopted. For example, in the fifth embodiment shown in FIG. 17, the gas path 53 is connected to the atmosphere opening 30 without passing through the upper space 43. FIG. 17 is a cross-sectional view of the recording head 7 according to the fifth embodiment. FIG. 17 is a cross-sectional view taken along the line AA of the recording head 7 according to the first embodiment shown in FIG. It is a figure equivalent to the AA sectional view of recording head 7 in an embodiment.

  More specifically, as shown in FIG. 17, the upper part of the gas path 53 in the present embodiment is a first upper gas connection path 120 into which the second upper gas connection path 121 is inserted. A seal member 55 is disposed inside the first upper gas connection path 120. The first outer cover 35 in the present embodiment has a second upper gas connection path 121 protruding downward from a portion corresponding to the atmosphere opening 30 (that is, the side opposite to the atmosphere opening 30). Is formed. The tip of the second upper gas connection path 121 extends below the upper space 43 and is inserted into the gas path 53 (specifically, the first upper gas connection path 120) of the valve unit 34. Yes. The first upper gas connection path 120 and the second upper gas connection path 121 are airtightly connected via the seal member 55. As described above, the gas path 53 is opened to the atmosphere via the gas path of the first outer cover 35 without passing through the upper space 43, that is, through the second upper gas connection path 121 and the atmosphere opening 30. Therefore, a more accurate airtight inspection can be performed without sealing the upper space 43. Thereby, it is not necessary to ensure airtightness between the first outer cover 35 and the first inner cover 36, and the recording head 7 can be easily assembled. In addition, in the connection location of the 1st upper gas connection path 120 and the 2nd upper gas connection path 121, the connection of the 1st gas connection path 51 and the 2nd gas connection path 54 which are shown in FIGS. Any of the configurations of the portions or a configuration obtained by inverting the configuration in the vertical direction can be employed. Other configurations are the same as those in the first embodiment or the fourth embodiment described above, and thus the description thereof is omitted.

  In addition, although the valve unit 34 illustrated above was comprised with the single member, it is not restricted to this. The valve unit 34 may be composed of a plurality of members. For example, the member may be divided for each of the liquid path and the gas path. That is, the 1st member in the present invention and the 2nd member are not restricted to being constituted by a single member, and may be constituted by a plurality of members. In the first to fourth embodiments described above, as a part of the space in the present invention, a space in which electronic components such as a wiring member and a piezoelectric element are accommodated (that is, the connection space 97, the insertion space 83, and Piezoelectric element array accommodating space 96, etc.), a space defined by a thin film formed in a portion functioning as a compliance portion (ie, compliance space 101), or a space used for opening and closing a valve (ie, pressing space 119). However, the present invention is not limited to this. For example, the present invention is also applied to a space that is separated from the liquid flow path through a gas permeable member and depressurized by a pump or the like in order to defoam ink in the liquid flow path. it can.

  By the way, in each of the above-described embodiments, the so-called flexural vibration type piezoelectric element 93 is exemplified as the driving element that causes the pressure fluctuation in the ink in the pressure chamber 91, but is not limited thereto. For example, various actuators such as a so-called longitudinal vibration type piezoelectric element, a heating element, and an electrostatic actuator that varies the volume of the pressure chamber by using electrostatic force can be employed. Further, in each of the above-described embodiments, the recording head unit 2 (so-called line head) in which a plurality of recording heads 7 are arranged is exemplified as the liquid ejecting head. However, the present invention is not limited to this. The present invention can also be applied to a liquid ejecting head (so-called serial head) that ejects ink while scanning (reciprocating) in a direction orthogonal to the conveyance direction of a recording medium such as recording paper.

  In the above description, the recording head unit 2 that ejects ink has been described as an example of the liquid ejecting head. However, the present invention can also be applied to other liquid ejecting heads. For example, a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, an electrode material ejecting head used for forming an electrode such as an organic EL (Electro Luminescence) display, FED (surface emitting display), a biochip (biochemical element) The present invention can also be applied to bioorganic matter ejecting heads and the like used in the production of In a color material ejecting head for a display manufacturing apparatus, a solution of each color material of R (Red), G (Green), and B (Blue) is ejected as a kind of liquid. Further, an electrode material ejecting head for an electrode forming apparatus ejects a liquid electrode material as a kind of liquid, and a bioorganic matter ejecting head for a chip manufacturing apparatus ejects a bioorganic solution as a kind of liquid.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Recording head unit, 3 ... Ink tank, 4 ... Paper feed roller, 5 ... Conveyance mechanism, 6 ... Recording paper, 7 ... Recording head, 8 ... Liquid supply tube, 9 ... Paper feed motor, 11 ... Conveying belt, 12 ... conveying motor, 13 ... driving roller, 14 ... driven roller, 15 ... tension roller, 16 ... pressure roller, 18 ... linear scale, 19 ... detection head, 22 ... supply member, 23 ... base plate, 24 ... liquid Inlet port, 25 ... Connector, 26 ... Base through hole, 27 ... Holder, 28 ... Screw, 29 ... Flange part, 30 ... Air release port, 32 ... Unit head, 33 ... Intermediate flow path member, 34 ... Valve unit, 35 ... 1st outer cover, 36 ... 1st inner cover, 37 ... 2nd outer cover, 38 ... 2nd inner cover, 39 ... 1st cover opening, 40 2nd cover opening, 41 ... 3rd cover opening, 42 ... Board arrangement space, 43 ... Upper space, 44 ... Partition plate, 45 ... First relay board, 46 ... Connector space, 47 ... Terminal, 48 ... Upper Insertion flow path, 49 ... lower insertion flow path, 50 ... seal member, 51 ... first gas connection path, 52 ... lower space, 53 ... gas path, 54 ... second gas connection path, 55 ... seal member, 56 DESCRIPTION OF SYMBOLS ... Filter, 57 ... Filter chamber, 58 ... Pressure adjustment valve, 59 ... Pressure adjustment part, 60 ... Upper flow path, 61 ... Valve accommodation chamber, 62 ... Pressure adjustment chamber, 63 ... Pressure receiving member, 64 ... Inlet, 65 ... Lower flow path, 66 ... Film member, 67 ... Working piece, 68 ... Biasing member, 69 ... Atmospheric pressure space, 70 ... Distribution flow path, 73 ... Head accommodating space, 74 ... Fixed plate, 75 ... Fixed plate opening, 76 ... Wiring member placement space, 77 ... Flow path in holder 78: Second relay substrate, 79: First wiring member, 80: Second wiring member, 82: Head case, 83: Insertion space, 84: Liquid introduction path, 85 ... Nozzle plate, 86 ... Nozzle, 87 DESCRIPTION OF SYMBOLS ... Common liquid chamber, 88 ... Communication part, 89 ... Supply path, 90 ... Flow path board, 91 ... Pressure chamber, 92 ... Vibrating plate, 93 ... Piezoelectric element, 94 ... Sealing plate, 95 ... Penetrating part, 96 ... Piezoelectric Element array housing space, 97 ... Connection space, 98 ... Compliance substrate, 99 ... Fixed substrate, 100 ... Sealing film, 101 ... Compliance space, 102 ... Protrusion, 103 ... Bridge, 104 ... Upper connection path, 105 ... Lower Connection path 106, communication opening 107, mounting piece 108, mounting space 109, tip portion 110, tip connection path 111, flexible member, 113 connection port, 114 upper gas connection path 115 4 cover openings, 1 16 ... Pressure adjustment path, 117 ... Vertical path, 118 ... Horizontal path, 119 ... Press space, 120 ... First upper gas connection path, 121 ... Second upper gas connection path

Claims (11)

A nozzle for ejecting liquid;
A first member having a space, a first connection path communicating with the space, and a first liquid path for supplying a liquid to the nozzle;
A gas path from a second connection path connected to the first connection path to an opening that opens to a position different from the position facing the space; and the first liquid path and an external flow path. A second member having a second liquid path to be communicated,
The liquid ejecting head, wherein the first member and the second member are detachably attached in a state where the first connection path and the second connection path are hermetically connected.   The liquid ejecting head according to claim 1, wherein the first connection path and the second connection path are connected via an elastic member. Either one of the first connection path and the second connection path is formed in a protruding portion protruding from the first member or the second member,
The first connection path and the second connection path are connected by inserting the protruding portion into the other connection path of the first connection path or the second connection path. The liquid ejecting head according to claim 1, wherein the liquid ejecting head is a liquid ejecting head. An elastic member is provided between the protrusion and the inner wall surface of the other connection path,
The liquid ejecting head according to claim 3, wherein the elastic member is attached to an inner wall surface of the other connection path.   The liquid ejecting head according to claim 3, wherein a flange portion protruding from an inner wall surface is formed inside the one connection path.   The liquid ejecting head according to claim 3, wherein the protruding portion tapers toward a tip.   The liquid ejecting head according to claim 6, wherein the one connection path is opened in a direction intersecting a protruding direction of the protruding portion at a tip portion of the protruding portion. The first member has a third connection path different from the first connection path,
The second member has a fourth connection path different from the second connection path,
2. The third connection path and the fourth connection path are connected at a position different from a connection location between the first connection path and the second connection path. The liquid ejecting head according to claim 7. A flexible member having flexibility is disposed on the inner wall surface of either the space or the gas path,
9. The liquid ejecting head according to claim 1, wherein at least a part of the space or the gas path is partitioned from an outer space by the flexible member. 10. An inspection method for a liquid jet head according to any one of claims 1 to 9,
A connecting step of connecting the first connection path and the second connection path;
After the connection step, in a state where the first connection path and the second connection path are connected, an airtight inspection step of sending a fluid from the opening of the gas path;
And a liquid jet head inspection method.   After the connection step and before the airtightness inspection step, the first connection path and the second connection path are connected to each other without introducing a cleaning liquid from the opening of the gas path. The method of inspecting a liquid jet head according to claim 10, wherein a cleaning step of passing a cleaning liquid through one liquid path and the second liquid path is performed.

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