Patent Publication Number: US-2023134134-A1

Title: Liquid Ejecting Head And Liquid Ejecting Apparatus

Description:
The present application is based on, and claims priority from JP Application Serial Number 2021-180017, filed Nov. 4, 2021, the disclosure of which is hereby incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a liquid ejecting head that ejects a liquid from a nozzle and a liquid ejecting apparatus, and more particularly, to an ink jet recording head that ejects ink as the liquid and an ink jet recording apparatus. 
     2. Related Art 
     For example, an ink jet recording head (hereinafter, simply referred to as a recording head), which is a representative example of a liquid ejecting head that ejects liquid droplets, includes a plurality of head chips that eject ink, a holder holding the plurality of head chips, and a fixing plate to which the holder and the plurality of head chips are fixed (for example, see JP-A-2016-130026). 
     In the recording head described in JP-A-2016-130026, a space around a communicating part of a liquid introduction flow passage of a holder and a case flow passage of the head chip in a gap between the holder and the head chip is filled with an adhesive, and an upper surface of the head chip and a head mounting surface of the holder adhere to each other by the adhesive. 
     In the recording head with the configuration described above, the fixing plate is formed with an opening where a nozzle of the head chip is exposed. However, when the opening is sealed with a cap, an external force is applied to the fixing plate by the cap. In addition, when a medium to be recorded comes into contact with the fixing plate, the external force is applied to the fixing plate. When the external force is applied to the fixing plate as such, the adhesive filling a space between the head chip and the holder is crushed, such that the head chip is pushed closer to the holder, which may result in deformation of the fixing plate, which is problematic. 
     The problem may occur in the ink jet recording head having any configuration, and the same problem exists not only in an ink jet recording head that ejects ink but also in a liquid ejecting head that ejects a liquid other than ink. 
     SUMMARY 
     According to an aspect of the present disclosure, there is provided a liquid ejecting head including: a first head chip having a plurality of first nozzles that eject a liquid in an ejecting direction; a holder holding the first head chip; and a fixing plate to which the holder and the first head chip are fixed, having a first opening for exposing the plurality of first nozzles to an outside, in which a first adhesive surface formed with an opening of a flow passage is provided on an upper portion of the first head chip, the holder accommodates the first head chip between the holder and the fixing plate, and has a second adhesive surface formed with an opening of a flow passage communicating with the first head chip, the first adhesive surface and the second adhesive surface adhere to each other with a first adhesive so as to define a coupling flow passage that couples the flow passage communicating with the first head chip of the holder and the flow passage of the first head chip, the upper portion of the first head chip has a first contact portion, the holder has a first contacted portion facing the first contact portion, and a first dimension between the first contact portion and the first contacted portion is smaller than a second dimension between the first adhesive surface and the second adhesive surface. 
     According to another aspect of the present disclosure, there is provided a liquid ejecting apparatus including the liquid ejecting head in the aspect described above and a transport portion configured to transport a medium. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic view of an ink jet recording apparatus. 
         FIG.  2    is a sectional view of an enlarged main portion of the ink jet recording apparatus. 
         FIG.  3    is an exploded perspective view of a recording head according to a first embodiment. 
         FIG.  4    is a plan view of a head chip according to the first embodiment when viewed in a +Z direction. 
         FIG.  5    is a sectional view taken along line V-V in  FIG.  4   . 
         FIG.  6    is a sectional view of the recording head according to the first embodiment. 
         FIG.  7    is a sectional view of an enlarged main portion of the recording head according to the first embodiment. 
         FIG.  8    is a plan view of a recording head according to the first embodiment when viewed in a -Z direction. 
         FIG.  9    is a sectional view of a recording head according to a second embodiment. 
         FIG.  10    is a sectional view of a recording head according to a third embodiment. 
         FIG.  11    is a plan view of a head chip according to a fourth embodiment when viewed in the +Z direction. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, the present disclosure will be described based on embodiments. However, the following description shows an aspect of the present disclosure, and it is possible to make changes in an arbitrary manner within the scope of the present disclosure. The same reference numeral will be given to the same member in the drawings, and a redundant description thereof will be omitted. In the drawings, X, Y, and Z represent three spatial axes orthogonal to one another. In this specification, directions along these axes are described as X, Y, and Z directions. A direction of an arrow in the drawings is described as a positive (+) direction, and a direction opposite to the arrow is described as a negative (-) direction. The Z direction indicates a vertical direction, a +Z direction indicates a vertically downward direction, and a -Z direction indicates a vertically upward direction. Further, the three spatial axes of X, Y, and Z that do not limit the positive direction and the negative direction will be described as the X axis, the Y axis, and the Z axis, respectively. 
     First Embodiment 
       FIG.  1    is a schematic view of an ink jet recording apparatus.  FIG.  2    is a sectional view of an enlarged main portion of the ink jet recording apparatus, and is a sectional view taken along a plane perpendicular to the Y axis and passing through an ink jet recording head  1 , a transport mechanism  4 , and a moving mechanism  6  which will be described later. According to the present disclosure, an ink jet recording apparatus I (hereinafter, simply referred to as “recording apparatus I”) is a printing apparatus that performs an image or the like by ejecting and landing ink as droplets, which is a type of the liquid, onto the medium S such as a printing sheet and arranging dots formed on the medium S. As the medium S, any material such as a resin film or cloth can be used in addition to a recording sheet. 
     The recording apparatus I includes the ink jet recording head  1  (hereinafter, simply referred to as “recording head  1 ”) which is an example of the liquid ejecting head, a liquid container  3 , the transport mechanism  4  configured to feed out the medium S, a control unit  5 , and the moving mechanism  6 . The transport mechanism  4  is an example of a “transport portion”. 
     The liquid container  3  stores the ink ejected from the recording head  1 . Examples of the liquid container  3  include a cartridge that can be attached to and detached from the recording apparatus I, a bag-shaped ink pack that is formed of a flexible film, and an ink tank that can refill the ink. In the present embodiment, the cartridge that is attachably and detachably provided on the recording head  1  is used as the liquid container  3 . Moreover, the liquid container  3  separately stores inks having a plurality of different colors or types. 
     The control unit  5  is not particularly illustrated, and includes, for example, a control device such as a central processing unit (CPU) or a field programmable gate array (FPGA), and a storage device such as a semiconductor memory. The control unit  5  generally controls respective components of the ink jet recording apparatus I, that is, the transport mechanism  4 , the moving mechanism  6 , the recording head  1 , and the like, by executing a program stored in the storage device by the control device. 
     The transport mechanism  4  is controlled by the control unit  5  to transport the medium S in the +X direction. Specifically, the transport mechanism  4  includes a platen  400  provided on an apparatus main body  2 , a paper feed unit  410 , and a transport unit  420 . 
     The platen  400  is a member extending in the ±Y direction and supporting a surface opposite to a surface of the medium S where the ink is ejected, that is, a surface of the medium S on a +Z direction side. The platen  400  is disposed on the +Z direction side from the recording head  1  at least in a movement range of the recording head  1  in the ±Y direction, and has a surface facing a side of the recording head  1  and supporting the medium S. The platen  400  is disposed on a +X direction side from the paper feed unit  410  which will be described later, and disposed on a -X direction side from the transport unit  420  which will be described later. 
     The platen  400  may include an adsorption unit for adsorbing the medium S onto the surface of the platen  400  facing the recording head  1 . Examples of the adsorption unit include a unit that adsorbs the medium S by suction and a unit that electrostatically adsorbs the medium S by an electrostatic force. 
     The paper feed unit  410  transports the medium S in the +X direction and feeds the medium S to the recording head  1  disposed on the apparatus main body  2 . Specifically, the paper feed unit  410  includes a paper feed roller  411 , a paper feed driven roller  412 , and a drive unit such as a drive motor (not illustrated), and is disposed on the -X direction side from the recording head  1 . The paper feed roller  411  is a member extending in the ±Y direction, which is attached to the apparatus main body  2  in a rotatable manner around the Y axis and rotated by the drive unit. The paper feed driven roller  412  is a member extending in the ±Y direction, which is attached to the apparatus main body  2  in a rotatable manner around the Y axis and driven by the paper feed roller  411 . The paper feed roller  411  is disposed on the +Z direction side from the medium S, and the paper feed driven roller  412  is disposed on the -Z direction side from the medium S. The control unit  5  rotates the paper feed roller  411  by driving the drive unit. The medium S passes between the paper feed roller  411  and the paper feed driven roller  412 , which are rotating, and is transported to the +X direction side. The paper feed roller  411  may be disposed on the -Z direction side from the medium S, and the paper feed driven roller  412  may be disposed on the +Z direction side from the medium S. 
     The transport unit  420  transports the medium S in the +X direction and discharges the medium S to the outside of the apparatus main body  2 . Specifically, the transport unit  420  includes a transport roller  421 , a transport driven roller  422 , and a drive unit such as a drive motor (not illustrated), and is disposed on the +X direction side from the recording head  1 . The transport roller  421  is a member extending in the ±Y direction, which is attached to the apparatus main body  2   in a rotatable manner around the Y axis and rotated by the drive unit. The transport driven roller  422  is a member extending in the ±Y direction, which is attached to the apparatus main body  2  in a rotatable manner around the Y axis and driven by the transport roller  421 . The transport roller  421  is disposed on the +Z direction side from the medium S, and the transport driven roller  422  is disposed on the -Z direction side from the medium S. The control unit  5  rotates the transport roller  421  by driving the drive unit. The medium S passes between the transport roller  421  and the transport driven roller  422 , which are rotating, and is transported to the +X direction side. The transport roller  421  is disposed on the -Z direction side from the medium S, and the transport driven roller  422  is disposed on the +Z direction side from the medium S. 
     The medium S is transported by the paper feed unit  410  in the +X direction and fed to the recording head  1 . The medium S is supported by the platen  400  from the +Z direction side, and ink droplets ejected from the recording head  1  are landed onto the medium S. The medium S where the ink droplets are landed is discharged to the outside of the apparatus main body  2  by the transport unit  420 . 
     The transport mechanism  4  configured to transport the medium S is not limited to a structure using a roller such as the paper feed roller  411  or the transport roller  421 , and may be a roller transporting the medium S by a belt or a drum. 
     The moving mechanism  6  is controlled by the control unit  5  to reciprocate the recording head  1  in the ±Y direction. The ±Y direction in which the moving mechanism  6  reciprocates the recording head  1  is a direction intersecting the +X direction in which the medium S is transported. 
     Specifically, the moving mechanism  6  in the present embodiment includes a holding member  7 , a transport belt  8 , and a guide rail  8   b  for holding the recording head  1 . The holding member  7  is a substantially box-shaped structure accommodating the recording head  1 , a so-called carriage, and is fixed to the transport belt  8 . The transport belt  8  is an endless belt provided along the ±Y direction. A driving force of a drive motor  8   a  is transmitted to the transport belt  8  under the control of the control unit  5 , and the transport belt  8  is rotated, thus reciprocating the recording head  1  together with the holding member  7  along the guide rail  8   b  extending along the ±Y direction. In the recording apparatus I, the recording head  1  ejects the ink to the medium S in parallel with transporting of the medium S and reverse reciprocating of the recording head  1 , thereby forming a desired image on a surface of the medium S. The liquid container  3  is mounted on the holding member  7  together with the recording head  1 , but the present embodiment is not limited to such a configuration. The liquid container  3  can be mounted in the apparatus main body  2  separately from the recording head  1 . 
     The recording apparatus I is provided with a cap  9  on the -Y direction side. Although the detailed configuration of the cap  9  will be described later, the cap  9  is a member sealing a nozzle  11  (see  FIG.  5   ) of the recording head  1 , which is provided on the recording apparatus I so as to be movable in the +Z direction. The control unit  5  controls the recording head  1  to move to a position where the recording head  1  overlaps with the cap  9  when viewed in the +Z direction, and controls the cap  9  to move to the recording head  1  side, such that the nozzle  11  is sealed in a closed space  9   a  (see  FIG.  7   ) formed by the cap  9  and the recording head  1 . 
     An example of the recording apparatus I described above includes, but is not limited to, an apparatus that reciprocates the recording head  1  in the ±Y direction. For example, the present disclosure can be also applied to a so-called line recording apparatus in which the recording head  1  is longer than a width of the medium S, and printing is performed only by moving the medium S in the ±X direction without moving the recording head  1  while the liquid is ejected to the medium S for printing. 
       FIG.  3    is an exploded perspective view of the recording head  1 . The recording head  1  includes a head chip  10 , a holder  70 , and a fixing plate  80 . In the present embodiment, one recording head  1  includes four head chips  10 , in which a first head chip  10 A, a second head chip  10 B, a third head chip  10 C, and a fourth head chip  10 D are arranged from the +Y direction side to the -Y direction side. The number of head chips  10  held by the holder  70  is not limited to four, may be two or more, or may be one. In addition, the arrangement of a plurality of head chips  10  is not limited to an example illustrated in  FIG.  3   . 
     Hereinafter, the description of “head chips  10 A to  10 D” refers to the first head chip  10 A, the second head chip  10 B, the third head chip  10 C, and the fourth head chip  10 D. The configuration common to the head chips  10 A to  10 D will be described as the head chip  10 . The specific configuration of each of the “head chips  10 A to  10 D” will be described as the first head chip  10 A, the second head chip  10 B, the third head chip  10 C, or the fourth head chip  10 D. 
     An example of the head chip  10  will be described with reference to  FIGS.  4  and  5   .  FIG.  4    is a plan view of the head chip  10  when viewed in the +Z direction, and  FIG.  5    is a sectional view taken along line V-V in  FIG.  4   .  FIG.  5    illustrates a section of the fixing plate  80 . In the present embodiment, each direction of the head chip  10  will be described based on a direction when the head chip  10  is mounted on the recording head  1 . 
     The head chip  10  includes a plurality of nozzles  11 , a case  13 , and a flexible substrate  23 . The head chip  10  in the present embodiment further includes a communication plate  14 , a pressure chamber forming substrate  15 , a vibration plate  16 , a compliance substrate  17 , a piezoelectric actuator  18 , and the like. A plurality of constituent members constituting the head chip  10  are stacked and bonded with an adhesive or the like to form a unit. 
     The plurality of nozzles  11  are formed on a nozzle plate  12  and discharges the ink toward the +Z direction. The nozzle  11  of the first head chip  10 A is an example of a “first nozzle”, and the nozzle  11  of the second head chip  10 B is an example of a “second nozzle”. A surface on which the nozzle  11  of the nozzle plate  12  is provided is referred to as a nozzle surface. 
     The pressure chamber forming substrate  15  has a plurality of pressure chambers  19  communicating the plurality of nozzles  11  formed on the nozzle plate  12 , respectively. A plurality of piezoelectric actuators  18  are provided for the corresponding pressure chambers  19 . The piezoelectric actuator  18  is a pressure generating element or an energy generating element that generates energy required for pressure fluctuation in the ink in the corresponding pressure chamber  19 , that is, for ejecting the ink from the nozzle  11  communicating with the pressure chamber  19 . The vibration plate  16  is provided between the pressure chamber  19  and the piezoelectric actuator  18 . The vibration plate  16  seals an opening of the pressure chamber  19  on the -Z direction side to partition a part of the pressure chamber  19 . The pressure chamber forming substrate  15  and the vibration plate  16  may be integrally formed. The respective piezoelectric actuators  18  are each stacked in a region corresponding to the corresponding pressure chamber  19  on the vibration plate  16 . The piezoelectric actuator  18  in the present embodiment has a first electrode  20 , a piezoelectric layer  21 , and a second electrode  22  which are sequentially stacked on the vibration plate  16 . The piezoelectric actuator  18  having such a configuration is bent and deformed when an electric field caused due to a potential difference between the first electrode  20  and the second electrode  22  is applied. 
     Moreover, the flexible substrate  23  is coupled to the piezoelectric actuator  18 . In the present embodiment, each electrode of the piezoelectric actuator  18  and the flexible substrate  23  are coupled to each other through lead-out wiring  24  that is led out from the piezoelectric actuator  18  onto the vibration plate  16 . The flexible substrate  23  is mounted with a circuit substrate having a switching element such as a transmission gate for driving the piezoelectric actuator  18  or a drive circuit  25  such as a semiconductor integrated circuit (IC). Such a flexible substrate  23  is led out in the -Z direction of the pressure chamber forming substrate  15 . The flexible substrate  23  is not limited to a chip on film (COF) substrate provided with the drive circuit  25  as described above. For example, instead of the flexible substrate  23 , flexible wiring on which no drive circuit  25  is mounted, such as flexible flat cable (FFC) and flexible printed circuit (FPC), may be used. 
     The communication plate  14  having a larger area than the pressure chamber forming substrate  15  is bonded to a surface of the pressure chamber forming substrate  15  on the +Z direction side, in plan view when viewed in the +Z direction. The communication plate  14  is formed with a nozzle communication port  26  for communication between the pressure chamber  19  and the nozzle  11 , a common liquid chamber  27  commonly provided in each pressure chamber  19 , and a separate communication port  28  for communication between the common liquid chamber  27  and the pressure chamber  19 . The common liquid chamber  27  is a space extending along the ±X direction as a direction in which the nozzles  11  are arranged side by side. In the present embodiment, two common liquid chambers  27  are formed corresponding to respective rows of two nozzles  11  provided on the nozzle plate  12 . A plurality of separate communication ports  28  are each formed for a corresponding one of the pressure chambers  19  along the ±X direction as a nozzle row direction. The separate communication port  28  communicates with an end portion of the pressure chamber  19 , which is opposite to a part communicating with the nozzle communication port  26 . 
     The nozzle plate  12  on which the plurality of nozzles  11  are formed is bonded to a substantially central part of a surface of the communication plate  14  on the +Z direction side. In the present embodiment, the nozzle plate  12  is a plate having an outer shape smaller than that of the communication plate  14 , in plan view when viewed in the -Z direction. The nozzle plate  12  is bonded to a region of a surface of the communication plate  14  on the +Z direction side, which is a position away from an opening of the common liquid chamber  27  and in which the nozzle communication port  26  is opened, with an adhesive or the like, in a state in which the nozzle communication ports  26  and the plurality of nozzles  11  communicate with each other. In the present embodiment, the nozzle plate  12  is formed with a total of two nozzle rows (not illustrated) in which the plurality of nozzles  11  are arranged side by side in the ±X direction, which is the nozzle row direction described above. The two nozzle rows are arranged side by side in the ±Y direction. 
     Moreover, the compliance substrate  17  is bonded to the position away from the nozzle plate  12  on the surface of the communication plate  14  on the +Z direction side. The compliance substrate  17  seals the opening of the common liquid chamber  27  on the surface of the communication plate  14  on the +Z direction side, in a state in which the compliance substrate  17  is positioned on the surface of the communication plate  14  on the +Z direction side and bonded thereto. 
     In the present embodiment, the compliance substrate  17  includes a flexible sealing film  17   a  formed of a thin film such as resin, and a frame member  17   b  formed of a hard material such as metal of stainless steel or the like. A region facing the common liquid chamber  27  of the frame member  17   b  is a compliance opening portion  17   c  that is totally removed in a thickness direction. Therefore, one surface of the common liquid chamber  27  is a compliance portion  17   d  which is a flexible portion sealed by only the flexible sealing film  17   a . The compliance portion  17   d  is bent and deformed, thus having a function of reducing the pressure fluctuation in an ink flow passage, particularly, the common liquid chamber  27 . 
     Moreover, a protective substrate  29  having the substantially same size as the pressure chamber forming substrate  15  is bonded to the pressure chamber forming substrate  15  in the -Z direction. The protective substrate  29   has a holding portion  30  which is a space for protecting the piezoelectric actuator  18 . 
     The pressure chamber forming substrate  15 , the protective substrate  29 , and the communication plate  14  are fixed to the case  13 . Inside the case  13 , introduction liquid chambers  31  communicating with the common liquid chamber  27  of the communication plate  14  are formed on both sides of the case  13  with the pressure chamber forming substrate  15  being interposed therebetween. Further, the protective substrate  29  and the case  13  are provided with a wiring insertion hole  33  through which the flexible substrate  23  is inserted. The flexible substrate  23  drawn out from the pressure chamber forming substrate  15  in the -Z direction is inserted through the wiring insertion hole  33  of the protective substrate  29  and the case  13 , and drawn out to the case  13  on the -Z direction side. 
     An adhesive portion  40  is provided on an upper portion of the head chip  10 , that is, on a part of the case  13  on the -Z direction side. The adhesive portion  40  has a shape protruding from the upper portion of the case  13  to the -Z direction side. In addition, the adhesive portion  40  is provided on each of both ends of the case  13  in the ±X direction. A first supply flow passage  101  for communicating with the introduction liquid chamber  31  is formed in the adhesive portion  40  on the +X direction side. A first discharge flow passage  111  for communicating with the introduction liquid chamber  31  is formed in the adhesive portion  40  on the -X direction side. In the present embodiment, two common liquid chambers  27  are formed in one head chip  10 , and each common liquid chamber  27  is provided with one first supply flow passage  101  and one first discharge flow passage  111 . 
     An adhesive surface  41  is a surface of the adhesive portion  40  on the -Z direction side. The first supply flow passage  101  is opened in the adhesive surface  41  of the adhesive portion  40  on the +X direction side, and an opening of the first discharge flow passage  111  is formed in the adhesive surface  41  of the adhesive portion  40  on the -X direction side. Although the details thereof will be described later, the adhesive surface  41  is applied with a first adhesive  45  (see  FIG.  6   ) around the first supply flow passage  101  and the opening of the first discharge flow passage  111  in the adhesive surface  41 . The adhesive surface  41  is provided for each of the head chips  10 A to  10 D. The adhesive surface  41  of the first head chip  10 A is an example of a “first adhesive surface”, and the adhesive surface  41  of the second head chip  10 B is an example of a “third adhesive surface”. 
     As illustrated in  FIG.  6   , a contact portion  51  and a contact portion  52  are provided on the upper portion of the head chip  10 . The contact portion  51  faces a contacted portion  71  of the holder  70  which will be describe later, and the contact portion  52  faces a contacted portion  72  of the holder  70  which will be described later. Specifically, the contact portion  51  and the contact portion  52  have a cylindrical shape protruding from the upper portion of the case  13  to the -Z direction side. The shapes of the contact portion  51  and the contact portion  52  are not limited to the cylindrical shape. The contact portion  51  is provided for each of the head chips  10 A to  10 D. The contact portion  51  of the first head chip  10 A is an example of a “first contact portion”, and the contact portion  51  of the second head chip  10 B is an example of a “third contact portion”. In addition, the contact portion  52  provided on the first head chip  10 A is an example of a “second contact portion”. 
     Moreover, the contact portion  51  is disposed on the -X direction side, and the contact portion  52  is disposed on the +X direction side, with respect to a longitudinal direction of the head chip  10 , in the present embodiment, with respect to the center of the head chip  10  in the ±X direction. In such a disposition, two sets of the contact portion  51  and the contact portion  52  are disposed in the ±Y direction with the wiring insertion hole  33  being interposed therebetween. 
     A non-contact portion  43  which does not come into contact with the holder  70  is provided on the upper portion of the head chip  10 . In the present embodiment, the non-contact portion  43  is a part on the upper portion of the head chip  10  in which the adhesive portion  40 , the contact portion  51 , and the contact portion  52  are not provided. The non-contact portion  43  is a surface facing the holder  70 , and is formed substantially planar. 
     The adhesive surface  41  and the contact portion  51  located on the -X direction side are disposed so as to interpose the non-contact portion  43  therebetween, when viewed in the +Z direction. Similarly, the adhesive surface  41  and the contact portion  52  located on the +X direction side are disposed so as to interpose the non-contact portion  43  therebetween when viewed in the +Z direction. 
     Moreover, an area of the non-contact portion  43  is larger than that of the contact portion  51 , when viewed in the +Z direction. Similarly, the area of the non-contact portion  43  is larger than that of the contact portion  52 , when viewed in the +Z direction. In addition, the non-contact portion  43  is larger than the contact portion  51  and the contact portion  52 , in the ±X direction which is the longitudinal direction of the head chip  10  and the ±Y direction which is a transverse direction of the head chip  10 . 
     Moreover, the contact portion  51  is located in the -Z direction opposite to the +Z direction, which is an ink ejecting direction, from the adhesive surface  41 . Similarly, the contact portion  52  is located in the -Z direction opposite to the +Z direction, which is the ink ejecting direction, from the adhesive surface  41 . 
     Configurations of the holder  70  for holding the head chip  10 , the fixing plate  80 , a circuit substrate  95 , and a flow passage member  90  will be described with reference to  FIGS.  3 ,  6 ,  7 , and  8   .  FIG.  6    is a sectional view of the recording head  1  with an appropriately bent sectional line, so as to include the adhesive surface  41 , the introduction liquid chamber  31 , the first supply flow passage  101 , the contact portion  51 , and the contact portion  52 .  FIG.  7    is a sectional view of an enlarged main portion of the recording head  1  taken along a plane, as a section, perpendicular to the ±X direction and passing through the center of the head chip  10  in the ±X direction.  FIG.  8    is a plan view of the recording head  1  when viewed in the -Z direction. In  FIG.  8   , a broken line indicates an outer shape of each of the head chips  10 A to  10 D, an alternate long and short dash line indicates an abutting position  83  which will be described later, and a hatching region indicates a fixed position  82  which will be described later. 
     The holder  70  is a member holding the four head chips  10  and accommodating the four head chips  10  between the holder  70  and the fixing plate  80 . Specifically, the holder  70  includes a plate-shaped base portion  75 , an outer peripheral wall  76  protruding from the base portion  75  to the +Z direction side. The plurality of head chips  10  are accommodated in a plurality of accommodating portions  77  formed by a surface of the base portion  75  on the +Z direction side and an inner surface of the outer peripheral wall  76 . As understood from  FIGS.  6  to  8   , the outer peripheral wall  76  includes a frame-shaped outermost wall  76   a  and a plurality of partition wall portions  76   b , when viewed in the -Z direction. Specifically, when viewed in the -Z direction, the outermost wall  76   a  is provided to surround the four head chips  10 , and the plurality of partition wall portions  76   b  divide the accommodating portion  77  surrounded by the outermost wall  76   a  into a plurality of portions. That is, each head chip  10  is disposed one by one in the accommodating portion  77 , which is a space surrounded by a part of the outermost wall  76   a  and one or more partition wall portions  76   b , when viewed in the -Z direction. In the present embodiment, because three partition wall portions  76   b  are provided, four accommodating portions  77  are provided corresponding to the four head chips, respectively. The outer peripheral wall  76  may include only the outermost wall  76   a  without having the partition wall portion  76   b , and may accommodate the plurality of head chips in one accommodating portion  77 . Further, the number of partition wall portions  76   b  may be any number including zero. 
     The holder  70  has a second supply flow passage  102  and a second discharge flow passage  112 , which penetrate the base portion  75  in the ±Z direction, as examples of a flow passage communicating with the head chip  10 . In the present embodiment, two second supply flow passages  102  are provided corresponding to two first supply flow passages  101  provided in the head chip  10 . Similarly, two second discharge flow passages  112  are provided corresponding to two first discharge flow passage  111  provided in the head chip  10 . 
     An adhesive surface  42  is a surface of the holder  70  on the +Z direction side and a surface applied with the first adhesive  45  which will be described later. The adhesive surface  42  is formed with openings of the second supply flow passage  102  and the second discharge flow passage  112 . The adhesive surface  42  is provided on the holder  70  corresponding to each of the head chips  10 A to  10 D. However, the adhesive surface  42  provided on the holder  70  corresponding to the first head chip  10 A is an example of a “second adhesive surface”, and the adhesive surface  42  provided on the holder  70  corresponding to the second head chip  10 B is an example of a “fourth adhesive surface”. 
     Moreover, the holder  70  has the contacted portion  71  facing the contact portion  51 , and the contacted portion  72  facing the contact portion  52 . In the present embodiment, a bottom surface  78  of the holder  70  on the +Z direction side inside the outer peripheral wall  76  is formed planar, and the contacted portion  71  is a part of the bottom surface  78  facing the contact portion  51 . In addition, the contacted portion  72  is a part of the bottom surface  78  facing the contact portion  52 . Two contacted portions  71  are provided corresponding to two contact portions  51 , respectively, and two contacted portions  72  are provided corresponding to two contact portions  52 , respectively. The contacted portion  71  is provided on the holder  70  corresponding to each of the head chips  10 A to  10 D. The contacted portion  71  provided on the holder  70  corresponding to the first head chip  10 A is an example of a “first contacted portion”, and the contacted portion  71  provided on the holder  70  corresponding to the second head chip  10 B is an example of a “third contacted portion”. The contacted portion  72  is provided on the holder  70  corresponding to each of the head chips  10 A to  10 D. The contacted portion  72  provided on the holder  70  corresponding to the first head chip  10 A is an example of a “second contacted portion”. 
     A flow passage member  90  is provided in the holder  70  on the -Z direction side. The flow passage member  90  has a third supply flow passage  103  which is a flow passage through which the ink is supplied from the liquid container  3  on a surface of flow passage member  90  on the -Z direction side. In addition, the flow passage member  90  has a third discharge flow passage  113  as a flow passage through which the ink is discharged from the head chip  10  on a surface of flow passage member  90  on the -Z direction side. 
     Although not particularly illustrated, the third supply flow passage  103  is branched so as to have one opening that is coupled to the liquid container  3  and two openings coupled to the second supply flow passage  102  of the holder  70 . As described above, two first supply flow passages  101  are provided in one head chip  10 , and two second supply flow passages  102  are provided in the holder  70  corresponding to the two first supply flow passages  101 . The third supply flow passage  103  is branched in order to supply the ink from one liquid container  3  to the two second supply flow passages  102 . Four third supply flow passages  103  are provided corresponding to the number of liquid containers  3 , which is four in the present embodiment. 
     Although not particularly illustrated, the third discharge flow passage  113  is branched so as to have one opening that is coupled to the liquid container  3  and two openings coupled to the second discharge flow passage  112  of the holder  70 . As described above, two first discharge flow passages  111  are provided in one head chip  10 , and two second discharge flow passages  112  are provided in the holder  70  corresponding to the two first discharge flow passages  111 . The third discharge flow passage  113  is merged in order to discharge the ink from the two second discharge flow passages  112  to one liquid container  3 . Four third discharge flow passages  113  are provided corresponding to the number of liquid containers  3 , which is four in the present embodiment. 
     The holder  70  holds the circuit substrate  95  between the holder  70  and the flow passage member  90 . Specifically, a recessed portion  91  is formed in a surface of the flow passage member  90  on the +Z direction side. The circuit substrate  95  is fixed to the flow passage member  90  on the +Z direction side and the holder  70  on the -Z direction side, and is accommodated in a space formed by the recessed portion  91  and the holder  70 , in a state in which the circuit substrate  95  is located on the holder  70 , that is, stacked on the holder  70 . 
     The circuit substrate  95  is a rigid substrate that is common to the plurality of flexible substrates  23  of the plurality of head chips  10 . The base portion  75  of the holder  70  is formed with a first substrate insertion hole  98  which penetrates in the ±Z direction and through which the flexible substrate  23  can be inserted. Further, the circuit substrate  95  is formed with a second substrate insertion hole  97  which penetrates in the ±Z direction and through which the flexible substrate  23  can be inserted. The flexible substrate  23  of each head chip  10  is folded by being inserted through the first substrate insertion hole  98  and the second substrate insertion hole  97 , and electrically coupled to a surface of the circuit substrate  95  on the -Z direction side. Further, the circuit substrate  95  is provided with a first insertion hole  96  through which the third supply flow passage  103  and the third discharge flow passage  113  are inserted. The third supply flow passage  103  is inserted through the first insertion hole  96  and coupled to the second supply flow passage  102 . The third discharge flow passage  113  is inserted through the first insertion hole  96  and coupled to the second discharge flow passage  112 . 
     Moreover, the fixing plate  80  is fixed to each head chip  10 . The fixing plate  80  is a plate-shaped member formed of a metal material such as stainless steel, and includes an opening  81  for exposing the plurality of nozzles  11  of the head chip  10  to the outside. In the present embodiment, a plurality of openings  81  are independently formed for each head chip  10  so as to have a size in which the nozzle plate  12  of the head chip  10  is exposed. In this case, the opening  81  that exposes the plurality of nozzles  11  of the first head chip  10 A to the outside is an example of a “first opening”, and the opening  81  that exposes the plurality of nozzles  11  of the second head chip  10 B to the outside is an example of a “second opening”. 
     The head chip  10  is fixed to the fixing plate  80 . The “head chip  10  is fixed to the fixing plate  80 ” means that the fixing plate  80  is fixed to the head chip  10  on the +Z direction side. The “head chip  10  is fixed to the fixing plate  80 ” is not limited to a portion of the head chip  10  to which the fixing plate  80  is fixed, and in the present embodiment, means that the fixing plate  80  is fixed to the compliance substrate  17 . Of course, the present embodiment is not limited to such a configuration, for example, the fixing plate  80  may be fixed to the nozzle plate  12 . 
     Moreover, the holder  70  is fixed to the fixing plate  80 . In the present embodiment, the fixing plate  80  is fixed to the outer peripheral wall  76  of the holder  70 . That is, a tip of the outer peripheral wall  76  on the +Z direction side is fixed to the fixing plate  80 . A part of the fixing plate  80  to which the outer peripheral wall  76  is fixed is referred to as the fixed position  82 . When viewed in the -Z direction, the outer peripheral wall  76 , in other words, the outermost wall  76   a  and the partition wall portion  76   b  surround the head chip  10  at an interval from the head chip  10 . 
     As described above, the head chip  10  of which the +Z direction side is fixed to the fixing plate  80  adheres to the holder  70  with the first adhesive  45  on the -Z direction side. Specifically, the adhesive surface  41  of the head chip  10  and the adhesive surface  42  of the holder  70  adhere to each other with the first adhesive  45 . 
     The first adhesive  45  adheres to the head chip  10  and the holder  70 , and defines a coupling flow passage  44  coupled between the first supply flow passage  101  and the second supply flow passage  102 . Similarly, the first adhesive  45  defines the coupling flow passage  44  coupled between the first discharge flow passage  111  and the second discharge flow passage  112 . The first adhesive  45  is not necessarily provided on the entire surface of the adhesive surface  41  or adhesive surface  42 , and may be provided in the vicinity of the openings of the first supply flow passage  101 , the second supply flow passage  102 , the first discharge flow passage  111 , and the second discharge flow passage  112 . As the first adhesive  45 , for example, a silicone-based adhesive can be used, but the present embodiment is not limited thereto. 
     It has been described that the holder  70  accommodates the head chip  10  between the holder  70  and the fixing plate  80 . However, this means that the head chip  10  on the +Z direction side is fixed to the fixing plate  80 , and the head chip  10  on the -Z direction side adheres to the holder  70 , in a state in which the head chip  10  is disposed between the holder  70  and the fixing plate  80 . 
     In the recording head  1  including the head chip  10  of the above-described configuration, the ink in the liquid container  3  is supplied to the first supply flow passage  101  of the head chip  10  through the third supply flow passage  103  provided in the flow passage member  90 , the second supply flow passage  102  provided in the holder  70 , and the coupling flow passage  44  formed by the first adhesive  45 . In a state in which the flow passage from the first supply flow passage  101  to the introduction liquid chamber  31 , the nozzle  11  passing through the common liquid chamber  27  and the pressure chamber  19  is filled with the ink, the piezoelectric actuator  18  is driven, and the pressure fluctuation in the ink thus occurs in the pressure chamber  19 , and the ink is ejected from a predetermined nozzle  11  due to the pressure fluctuation. In addition, in the recording head  1 , the ink that has not been ejected from the nozzle  11  is discharged from the introduction liquid chamber  31  to the first discharge flow passage  111 , the coupling flow passage  44 , the second discharge flow passage  112 , and the third discharge flow passage  113 . The recording head  1  is a circulation-type recording head  1  in which the ink discharged from the third discharge flow passage  113  is supplied from the third supply flow passage  103  to the head chip  10  again. 
     As illustrated in  FIGS.  1  and  7   , the recording apparatus I is provided with the cap  9  corresponding to each head chip  10  that is accommodated between the holder  70  and the fixing plate  80 . 
     That is, the caps  9  are separately provided for the head chips  10 A to  10 D and are also referred to as caps  9 A,  9 B,  9 C, and  9 D (the cap  9 D is not illustrated in  FIG.  7   ). Hereinafter, the description of the “caps  9 A to  9 D” means the caps  9 A,  9 B,  9 C, and  9 D. The configuration common to the caps  9 A to  9 D will be described as the cap  9 . 
     Each of the caps  9 A to  9 D has a shape capable of closing the openings  81  provided corresponding to the head chips  10 A to  10 B, respectively. The “first cap” corresponds to the cap  9 A provided on the first head chip  10 A, and the “second cap” corresponds to the cap  9 B provided on the second head chip  10 B. 
     The apparatus main body  2  includes the cap  9  as a constituent element of a maintenance unit (not illustrated). The maintenance unit includes the cap  9 , a moving mechanism (not illustrated) for moving the cap  9 , and a suction pump (not illustrated). 
     The cap  9  is a bottomed box-shaped member that is open to the -Z direction side and has a plate-shaped bottom portion  901  facing the nozzle plate  12  and a wall portion  902  extending from each side of the bottom portion  901  to the -Z direction side. A shape of the opening of the cap  9  is at least larger than that of the opening  81  of the fixing plate  80 . 
     The recording head  1  can move to the -Y direction side along the guide rail  8   b  and stop at a predetermined position on the -Y direction side from the -Y direction side from a range in which the medium S is transported. The predetermined position is referred to as a cap position. When the recording head  1  is stopped at the cap position, the cap  9  is disposed to face the nozzle plate  12  when viewed in the +Z direction and to cover the opening  81 . 
     A cap moving mechanism of the maintenance unit moves the cap  9  in the ±Z direction. In a state in which the recording head  1  stops at the cap position, the control unit  5  controls the cap moving mechanism to move the cap  9  to the -Z direction side. Due to the operation of the cap moving mechanism, the cap  9  moves from the +Z direction side to the -Z direction side at a position that is located inside the fixed position  82  and overlaps the head chip  10 , and comes into contact with the fixing plate  80 , when viewed in the +Z direction. As illustrated in  FIGS.  7  and  8   , a part of the fixing plate  80  which abuts a surface of the wall portion  902  of the cap  9  on the -Z direction side is the abutting position  83 . The abutting position  83  is located outside the opening  81  of the fixing plate  80  and inside the fixed position  82 . 
     The wall portion  902  of the cap  9  comes into contact with the abutting position  83  of the fixing plate  80  to close the opening  81 , such that the closed space  9   a  is formed by a part where the nozzle plate  12  of the recording head  1  is exposed to the opening  81 , an inner peripheral surface of the opening  81 , and the cap  9 . That is, the cap  9  functions as a seal that shields the nozzle  11  from the outside air. Therefore, it is possible to shield the nozzle  11  of the nozzle plate  12  from the outside air by forming the closed space  9   a  to stop the recording head  1  at the cap position and cover the nozzle plate  12  by the cap  9 . As a result, since the nozzle  11  can be moisturized, it is possible to prevent the ink from thickening in the vicinity of the nozzle  11 , for example. 
     The suction pump of the maintenance unit sets the closed space  9   a  formed by the cap  9  to a negative pressure. For example, the cap  9  is provided with a communication path (not illustrated) for allowing the closed space  9   a  to communicate with the outside, and it is possible to set the closed space  9   a  to a negative pressure through the communication path. 
     By setting the closed space  9   a  to the negative pressure by operating the suction pump in a state in which the closed space  9   a  is formed by the cap  9 , it is possible to perform cleaning in which the ink thickened in the ink flow passage of the recording head  1 , air bubbles, and the like accumulated in the flow path are forcibly discharged from the nozzle  11 . The cap  9  can also be used for receiving the ink ejected from the nozzle  11  by flushing without operating the suction pump. 
     In this case, a dimension between the contact portion  51  and the contacted portion  71  is defined as a first dimension H1. A dimension between the adhesive surface  41  and the adhesive surface  42  is defined as a second dimension H2. A dimension between the contact portion  52  and the contacted portion  72  is defined as a third dimension H3. The first dimension H1 is smaller than the second dimension H2, and the third dimension H3 is smaller than the second dimension H2. In a relationship in size between the first dimension H1 and the third dimension H3, one of the first dimension H1 and the third dimension H3 may be larger than the other dimension, or the first dimension H1 and the third dimension H3 may be substantially the same as each other. In addition, the contact portion  51  and the contacted portion  71  may be in contact with each other. That is, the first dimension H1 may be zero. The contact portion  52  and the contacted portion  72  may be in contact with each other. That is, the third dimension H3 may be zero. As for the second head chip  10 B, a “fourth dimension” between the “third contact portion” and the “third contacted portion” corresponds to the first dimension H1 in the first head chip  10 A, but the “fourth dimension” is smaller than the second dimension H2. 
     For example, the second dimension is 0.14 ± 0.11 mm (tolerance at the time of manufacturing). That is, the second dimension H2 is within a range of 0.03 to 0.25 mm. The first dimension H1 is preferably narrower than 0.03 mm, which is the minimum gap of the second dimension H2 in consideration of the tolerance. In other words, the first dimension H1 is preferably about 0.00 mm to 0.029 mm. Specifically, the first dimension H1 is more preferably 0.020 ± 0.009 mm, that is, about 0.011 mm to 0.029 mm. By setting the first dimension H1, the second dimension H2, and the third dimension H3 as such, deformation of the fixing plate  80  can be prevented as follows. 
     Moreover, a dimension between the non-contact portion  43  and a part facing the non-contact portion  43  of the holder  70  is defined as a dimension H. The dimension H is larger than the second dimension H2. That is, on the upper portion of the head chip  10 , the contact portion  51  and the contact portion  52  come into contact with the holder  70 , and the other non-contact portion  43  does not come into contact with the holder  70 . 
     As described above, the fixing plate  80  is fixed to the tip of the outer peripheral wall  76  of the holder  70 , and fixed to the head chip  10  that is disposed at an interval from the outer peripheral wall  76 . When the fixing plate  80  comes into contact with the cap  9  inside the fixed position  82  and at the abutting position  83  that overlaps with the head chip  10  when viewed in the +Z direction, an external force is applied to the -Z direction side in the vicinity of the head chip  10  of the fixing plate  80 . 
     When the external force is applied to the fixing plate  80  by the cap  9 , the head chip  10  is pushed in the -Z direction, and the first adhesive  45  is crushed. However, since the first dimension H1 is smaller than the second dimension H2, the contact portion  51  and the contacted portion  71  come into contact with each other. The contact restricts the head chip  10  from moving in the -Z direction due to the external force of the cap  9 . The movement of the head chip  10  to the -Z direction is restricted, such that it is possible to prevent the fixing plate  80  from being deformed in the -Z direction side. 
     Moreover, the external force due to the medium S may be applied to the fixing plate  80 . For example, when the medium S having the bent part or the wrinkled part is transported, or when the medium S has the bent part or winkled part in the middle of the transporting, the bent part or the wrinkled part reaches a space between the recording head  1  and the platen  400  (see  FIG.  2   ), such that the external force that allows the fixing plate  80  to be pressurized on the -Z direction side may be applied. Particularly, when the medium S is cloth, a thickness of the bent part or the wrinkled part in the ±Z direction tends to be thick, and the external force applied to the fixing plate  80  tends to be large. However, since the recording head  1  in the present embodiment can restrict the movement of the head chip  10  in the -Z direction by the contact between the contact portion  51  and the contacted portion  71  due to the external force of the medium S as described above, the recording head  1  can prevent the deformation of the fixing plate  80  even with respect to the external force caused by the medium S. 
     The Young’s modulus of the contact portion  51  and the contact portion  52  is higher than that of the first adhesive  45 . Specifically, the contact portion  51  and the contact portion  52  are rigid bodies that are not deformed by the external force applied from the cap  9  or the medium S via the fixing plate  80 . In the present embodiment, the contact portion  51  and the contact portion  52  are formed as a part of the case  13 . Examples of a material constituting such a case  13  include resin, metal and ceramic. The contact portion  51  and the contact portion  52  may be separated from the case  13 . 
     The Young’s moduli of the contacted portion  71  and the contacted portion  72  are higher than that of the first adhesive  45 . Specifically, the contacted portion  71  and the contacted portion  72  are rigid bodies that are not deformed by the external force applied from the cap  9  or the medium S via the fixing plate  80 . In the present embodiment, the contacted portion  71  and the contacted portion  72  are a part of the holder  70 . Examples of a material constituting such a holder  70  include resin, metal, and ceramic. The contacted portion  71  and the contacted portion  72  may be separated from the holder  70 . 
     The resin constituting the case  13  or the holder  70  may be, for example, a thermoplastic resin or a thermosetting resin. Examples of the thermoplastic resin include polyphenylene ether resin (PPE), modified polyphenylene ether resin (m-PPE), polyethylene resin (PE), polystyrene resin (PS), polyamide resin (PA), PPS, PP, LCP, ABS resin, vinyl chloride-vinyl acetate copolymer resin, polyvinyl chloride resins, and mixtures thereof. In addition, examples of the thermosetting resin include phenolic resin such as bakelite, epoxy resin such as epoxy glass, urethane resin, melamine resin, and ester resin. The case  13  or the holder  70  is preferably formed using the thermosetting resin having excellent temperature stability, liquid resistance, and high rigidity. 
     As described above, the recording head  1  according to the present embodiment includes the head chip  10 , the holder  70 , and the fixing plate  80 , and the head chip  10  is accommodated between the holder  70  and the fixing plate  80 . The adhesive surface  41 , the contact portion  51 , and the contact portion  52  are provided on the head chip  10 , and the adhesive surface  42 , the contacted portion  71 , and the contacted portion  72  are provided on the holder  70 . The head chip  10  adheres to the adhesive surface  42  with the first adhesive  45  on the adhesive surface  41 , and is fixed to the fixing plate  80 . The first dimension H1 is smaller than the second dimension H2, and the third dimension H3 is smaller than the second dimension H2. 
     Even when the external force in the -Z direction is applied to the head chip  10  via the fixing plate  80 , the recording head  1  can come into contact with the contact portion  51  and the contacted portion  71  for making the first dimension H1 smaller than the second dimension H2, and restrict movement of the head chip  10  to the -Z direction by the external force of the cap  9 . Since the movement of the head chip  10  to the -Z direction is restricted, such that it is possible to prevent the fixing plate  80  from being deformed. 
     Moreover, the head chip  10  and the holder  70  are fixed with the first adhesive  45 . Therefore, an inclination of the nozzle surface due to a dimensional error of each head chip  10  can be adjusted by changing a thickness of the first adhesive  45  in the ±Z direction when the head chip  10  is attached to the holder  70 . Particularly, the thickness of the first adhesive  45  in the ±Z direction is easily changed by adopting a silicone-based adhesive having a relatively small Young’s modulus as the first adhesive  45 . 
     The contact portion  51  and the contacted portion  71  as described in the embodiment are not in contact with each other in a state in which the external force is not applied to the fixing plate  80 . However, the contact portion  51  and the contacted portion  71  are not limited to such a configuration, and may be in direct contact with each other. In the recording head  1  in which the contact portion  51  and the contacted portion  71  are in direct contact with each other, the deformation of the fixing plate  80  can be reliably prevented, as compared with a case in which the contact portion  51  and the contacted portion  71  are not in contact with each other. 
     In addition to the contact portion  51  and the contacted portion  71 , when the contact portion  52  and the contacted portion  72  are provided, that is, when a plurality of sets of the contact portion and the contacted portion are provided, the contact portion and the contacted portion may be in contact with each other in all the sets, or the contact portion and the contacted portion may be in contact with each other only in any set. 
     Moreover, the recording head  1  in the present embodiment has an area of the non-contact portion  43  which is larger than those of the contact portion  51  and the contact portion  52 , when viewed in the +Z direction which is the ink ejecting direction. That is, the configuration in which the contact portion  51  and the contact portion  52  are provided on a part of the upper portion of the case  13  can improve accuracy of the first dimension H1 by improving surface accuracy of the contact portion  51  and the contact portion  52 , as compared with a configuration in which the contact portion is provided on the entire surface other than the adhesive surface  41  on the upper portion of the case  13 . 
     Moreover, the head chip  10  includes the case  13  having the contact portion  51  and the contact portion  52 , the contact portion  51  and the contact portion  52  are formed as a part of the upper portion of the case  13 . The rigid case  13  abuts the holder  70 , such that the deformation of the fixing plate  80  can be reliably prevented. 
     The head chip  10  includes the flexible substrate  23  coupled to the circuit substrate  95  and raised along the ±Z direction, which is the ink ejecting direction. Thus, the flexible substrate  23  capable of absorbing the tolerance to the ±Z direction can couple the drive circuit  25  of the head chip  10  and the circuit substrate  95  held by the holder  70 , such that the inclination of the head chip  10  to the holder  70  in the ±Z direction can be adjusted. The flexible substrate  23  may be raised obliquely with respect to the ±Z direction. 
     In the present embodiment, the recording head  1  has the contact portion  52  and the contacted portion  72 . When the third dimension H3 between the contact portion  52  and the contacted portion  72  is equal to the first dimension H1, the contact portion  51  and the contact portion  52  come into contact with the contacted portion  71  and the contacted portion  72 , respectively, by the external force of the fixing plate  80 . As such, since the plurality of contact portions come into contact with the contacted portion and receive the external force applied from the fixing plate  80 , it is possible to reliably prevent the fixing plate  80  from being deformed. When the third dimension H3 is not equal to the first dimension H1, either the contact portion  51  or the contact portion  52  comes into contact with the contacted portion  71  or the contacted portion  72 . That is, the plurality of sets of the contact portion and the contacted portion are provided. Even when the respective sets have different dimensions in the ±Z direction, one of the sets comes into contact with other sets, such that the deformation of the fixing plate  80  can be prevented as described above. 
     In the present embodiment, the contact portion  51  is disposed on the -X direction side, and the contact portion  52   is disposed on the +X direction side, with respect to a longitudinal direction of the head chip  10  and the center of the head chip  10  in the ±X direction in the present disclosure. By disposing the contact portion  51  and the contact portion  52  as such, the external force applied from the fixing plate  80  is distributed in the +X direction and the -X direction, such that the deformation of the fixing plate  80  can be further prevented. 
     In the present embodiment, the plurality of caps  9  are separately provided for the respective head chips  10 . Therefore, a large load is easily applied to the head chip  10  via the fixing plate  80  as compared with a configuration in which one cap  9  is commonly provided on the plurality of head chips  10 . However, even when the separate cap  9  is provided on the plurality of head chips  10 , the recording head  1  in the present embodiment can withstand such a large load and prevent the deformation of the fixing plate  80 . Further, the plurality of caps  9  are separately provided for the respective head chips  10 , such that it is possible to improve a moisture retaining property of the nozzle  11  and prevent clogging or the like. Also, a sealing property of the closed space  9   a  can be improved. 
     Second Embodiment 
       FIG.  9    is a sectional view of a recording head  1 A according to a second embodiment of the present disclosure. In detail,  FIG.  9    is a sectional view of the recording head  1  with an appropriately bent sectional line, so as to include the adhesive surface  41 , the introduction liquid chamber  31 , the first supply flow passage  101 , the contact portion  51 A, and the contact portion  52 A. The same reference numerals will be given to the same members as in the first embodiment in the drawings, and a redundant description thereof will be omitted. 
     A holder  70 A in the present embodiment is not provided with the second supply flow passage  102  and the second discharge flow passage  112  described in the first embodiment. The holder  70 A is provided with a second insertion hole  79  penetrating in the ±Z direction. 
     The third supply flow passage  103  provided in a flow passage member  90 A extends in the +Z direction and is inserted through the second insertion hole  79 . A surface of the third supply flow passage  103  on the +Z direction side adheres to the first adhesive  45 , and the third supply flow passage  103  communicates with the coupling flow passage  44  and the first supply flow passage  101 . An opening edge of the third supply flow passage  103  on the +Z direction side is the adhesive surface  42 . 
     The third discharge flow passage  113  provided in the flow passage member  90 A extends in the +Z direction and is inserted through the second insertion hole  79 . A surface of the third discharge flow passage  113  on the +Z direction side adheres to the first adhesive  45 , and the third discharge flow passage  113  communicates with the coupling flow passage  44  and the first discharge flow passage  111 . An opening edge of the third discharge flow passage  113  on the +Z direction side is the adhesive surface  42 . 
     The contact portion  51 A is located in the +Z direction, which is the ejecting direction, from the adhesive surface  41 . Similarly, the contact portion  52 A is located in the +Z direction, which is the ejecting direction, from the adhesive surface  41 . In addition, a contacted portion  71 A protrudes from a surface of the holder  70  facing the head chip  10 . Similarly, a contacted portion  72 A protrudes from the surface of the holder  70  facing the head chip  10 . 
     A first dimension H1 between the contact portion  51 A and the contacted portion  71 A is smaller than a second dimension H2. In addition, a third dimension H3 between the contact portion  52 A and the contacted portion  72 A is smaller than the second dimension H2. 
     The contact portion  51 A and the contacted portion  71 A adhere to each other via the second adhesive  46 , and the contact portion  52 A and the contacted portion  72 A adhere to each other via the second adhesive  46 . The second adhesive  46  may have the same composition as the first adhesive  45 , or may have a different composition. When the second adhesive  46  having the different composition from the first adhesive  45  is used, it is preferable that the second adhesive  46  has a higher Young’s modulus than the first adhesive  45 . When the silicone-based adhesive is used as the first adhesive  45 , an epoxy-based adhesive can be used as the second adhesive  46  having a higher Young’s modulus than the first adhesive  45 . 
     The Young’s moduli of the contact portion  51 A and the contact portion  52 A are higher than that of the second adhesive  46 . Further, a Young’s modulus of the contacted portion  71 A and the contacted portion  72 A is higher than that of the second adhesive  46 . 
     In the recording head  1 A having such a configuration, the adhesive surface  41  and the adhesive surface  42  adhere to each other with the first adhesive  45 , and the head chip  10  is fixed to the fixing plate  80 . The first dimension H1 is smaller than the second dimension H2, and the third dimension H3 is smaller than the second dimension H2. Therefore, the recording head  1 A has the same effect as the recording head  1  in the first embodiment. 
     The contact portion  51 A and the contacted portion  71 A adhere to each other via the second adhesive  46 . Such a recording head  1 A can reliably prevent the deformation of the fixing plate  80  as compared with a case in which the contact portion  51 A and the contacted portion  71 A are not in contact with each other. 
     The first adhesive  45  and the second adhesive  46  may be the same type, but the second adhesive  46  preferably has a higher Young’s modulus than the first adhesive  45 . In the recording head  1 A in which the contact portion  51 A and the contacted portion  71 A adhere to each other via the second adhesive  46  having a higher Young’s modulus than the first adhesive  45 , the deformation of the fixing plate  80  can be reliably prevented, as compared with a case in which the contact portion  51 A and the contacted portion  71 A are not in contact with each other, and furthermore, as compared with a case in which an adhesive that has the same Young’s modulus as the first adhesive  45  and the second adhesive  46  is used. 
     Third Embodiment 
       FIG.  10    is a sectional view of a recording head  1 B according to a third embodiment of the present disclosure. In detail,  FIG.  10    is a sectional view of the recording head  1  with an appropriately bent sectional line, so as to include the adhesive surface  41 , the introduction liquid chamber  31 , the first supply flow passage  101 , the contact portion  51 , and the contact portion  52 . The same reference numerals will be given to the same members as in the first and second embodiments in the drawings, and a redundant description thereof will be omitted. 
     In a recording head  1 B in the present embodiment, the circuit substrate  95  is disposed on an upper portion of a holder  70 B, that is, on the -Z direction side of the holder  70 B. 
     The second supply flow passage  102  provided in the holder  70 B protrudes from the bottom surface  78  in the +Z direction. A surface of the second supply flow passage  102  on the +Z direction side adheres to the first adhesive  45 , and the second supply flow passage  102  communicates with the coupling flow passage  44  and the first supply flow passage  101 . An opening edge of the second supply flow passage  102  on the +Z direction side is the adhesive surface  42 . 
     The second discharge flow passage  112  provided in the holder  70 B protrudes from the bottom surface  78  in the +Z direction. A surface of the second discharge flow passage  112  on the +Z direction side adheres to the first adhesive  45 , and the second discharge flow passage  112  communicates with the coupling flow passage  44  and the first discharge flow passage  111 . An opening edge of the second discharge flow passage  112  on the +Z direction side is the adhesive surface  42 . 
     In the recording head  1 B having such a configuration, the adhesive surface  41  and the adhesive surface  42  adhere to each other with the first adhesive  45 , and the head chip  10  is fixed to the fixing plate  80 . The first dimension H1 is smaller than the second dimension H2, and the third dimension H3 is smaller than the second dimension H2. Therefore, the recording head  1 B has the same effect as the recording head  1  in the first embodiment. 
     Fourth Embodiment 
       FIG.  11    is a plan view of the head chip  10  when viewed in the +Z direction. The same reference numerals will be given to the same members as in the first to third embodiments in the drawings, and a redundant description thereof will be omitted. 
     According to the first to third embodiments, the head chip  10  has a configuration in which the coupling flow passage  44  defined by the first adhesive  45  is disposed on each of an end portion on the +X direction side, which is the longitudinal direction, and an end portion of the -X direction side. That is, in the ±X direction, the head chip  10  has a configuration in which the coupling flow passage  44  is disposed outside thereof and the contact portion  51  and the contact portion  52  are disposed inside thereof. Such a configuration is preferable when the ink is circulated in the head chip  10 . 
     On the other hand, as illustrated in  FIG.  11   , the head chip  10  according to the present embodiment has a configuration in which the first discharge flow passage  111  is not provided, the first supply flow passage  101  is coupled to each of two common liquid chambers  27  (see  FIG.  5   ), and the coupling flow passage  44  (see  FIG.  6   ) is coupled to the first supply flow passage  101 . That is, the head chip  10  does not have a configuration in which the ink is circulated. 
     According to the present embodiment, the head chip  10   has a configuration in which the contact portion  51  and the contact portion  52  are disposed outside thereof, and the first supply flow passage  101  is disposed inside thereof, in the ±X direction. When the ink is not circulated in the head chip  10 , the contact portion  51  and the contact portion  52  are provided on the outside in the ±X direction, which is preferable in terms of strength of the head chip  10 . 
     Other Embodiments 
     As described above, the embodiments of the present disclosure have been described, but the basic configurations of the present disclosure are not limited to the embodiments described above. 
     In the embodiments, the contact portion  51  and the contact portion  52  are provided on the head chip  10 , but the present embodiment is not limited to the configuration in which the plurality of contact portions are provided. The number of contact portions may be one. 
     When one contact portion is provided, it is preferable that one contact portion is provided at the center of the head chip  10  in the ±X direction, which is the longitudinal direction of the head chip  10 . When two contact portions are provided, it is preferable that the two contact portions are provided on both ends of the head chip  10  in the ±X direction, respectively, as described in the fourth embodiment. It is preferable that four contact portions are provided at four corners at the center of the head chip  10  in the ±X direction, as described in the first embodiment. The “both ends of the head chip in the ±X direction, which is the longitudinal direction of the head chip” means respective parts of three to five parts into which the head chip  10  is virtually divided so as to be arranged in the ±X direction, the respective parts being located closest to both the ends of the head chip. The “center of the head chip in the ±X direction, which is the longitudinal direction of the head chip” means a region of a part inside the parts located closest to both the ends of the head chip described above. 
     In the embodiments, only a part of the head chip  10  forming the coupling flow passage  44  adheres to the holder  70  with the first adhesive  45 . By adhering with the first adhesive  45  as such, the inclination of the head chip  10  in the ±Z direction can be easily adjusted, and an amount of the adhesive used can be reduced. The first adhesive  45  may be applied not only to the part of the head chip  10  forming the coupling flow passage  44  but also to a part other than the part. That is, the first adhesive  45  may be provided between the non-contact portion  43  and the holder  70 . Thus, it is possible to firmly fix the head chip  10  by the holder  70 . 
     In the second and third embodiments, the contacted portion  71 A, the contacted portion  71 B, the contacted portion  72 A, and the contacted portion  72 B are provided so as to protrude from the bottom surface  78  of the holder  70  to the +Z direction side. However, the present embodiment is not limited to such a configuration. For example, the contacted portion may be provided so as to protrude from the outer peripheral wall  76  of the holder  70  toward the ±X direction or the ±Y direction. 
     In the embodiments, the fixing plate  80  is directly fixed to the head chip  10 , but the present embodiment is not limited to such a configuration. For example, a reinforcing plate may be provided between the fixing plate  80  and the head chip  10 , and the fixing plate  80  may be indirectly fixed to the head chip  10  through the reinforcing plate. 
     As long as the first dimension H1, the second dimension H2, and the third dimension H3 satisfy the relationships described above, the adhesive surface  41 , the contact portion  51 , the contact portion  51 A, the contact portion  52 , and the contact portion  52 A may protrude in the -Z direction from the non-contact portion  43 , or may be flush with the non-contact portion  43  or recessed in the +Z direction side from the non-contact portion  43 . 
     As long as the first dimension H1, the second dimension H2, and the third dimension H3 satisfy the relationships described above, the adhesive surface  42 , the contacted portion  71 , the contacted portion  71 A, the contacted portion  72 , and the contacted portion  72 A may protrude from the bottom surface  78  facing the head chip  10  of the holder  70  to the +Z direction side, or may be flush with the bottom surface  78  or recessed in the -Z direction from the bottom surface  78 . 
     Furthermore, the present disclosure is intended for a wide range of the liquid ejecting head. For example, the present disclosure can be also applied to recording heads such as various ink jet recording heads used in image recording apparatuses such as printers, coloring material ejecting heads used in manufacturing color filters for liquid crystal displays, and the like, electrode material ejecting heads used for electrode formation such as organic electroluminescent (EL) displays, field emission displays (FEDs), bio-organic matter ejecting heads used in biochip manufacturing, and the like. Although the ink jet recording apparatus has been described as an example of the liquid ejecting apparatus, a liquid ejecting apparatus using other liquid ejecting heads described above can be also used.