Patent Publication Number: US-11383517-B2

Title: Liquid ejecting head, liquid ejecting apparatus, and piezoelectric device

Description:
The present application is a continuation of U.S. patent application Ser. No. 15/804,819, filed Nov. 6, 2017, which claims priority to Japanese Patent Application No. 2016-235396, filed Dec. 2, 2016, the entire disclosures of which are expressly incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a liquid ejecting head which ejects a liquid from a nozzle, a liquid ejecting apparatus, and a piezoelectric device. In particular, the invention relates to an ink jet recording head which discharges an ink as the liquid, an ink jet recording apparatus, and a piezoelectric device. 
     2. Related Art 
     An ink jet recording head which discharges ink droplets is a representative example of the liquid ejecting head which discharges droplets. As this ink jet recording head, for example, there is known an ink jet recording head which includes a flow path forming substrate having a pressure generating chamber communicating with a nozzle opening and a piezoelectric actuator which is provided on one surface side of the flow path forming substrate, in which an ink droplet is ejected from a nozzle opening by using the piezoelectric actuator to generate a pressure change in the ink in a pressure generating chamber (for example, refer to Japanese Patent No. 5278654). 
     However, in order to obtain a high displacement amount in the piezoelectric actuator and in order to eject large ink droplets for the ink jet recording head, it is necessary to form the piezoelectric actuator long, that is, to form the piezoelectric actuator with a high aspect ratio, and there is a problem in that a space for disposing the piezoelectric actuator becomes necessary and the size becomes large. In particular, in a piezoelectric actuator having a high aspect ratio when viewed in plan view, since it is not possible to drive the end portion in the longitudinal direction, in order to improve the displacement amount of the piezoelectric actuator, it is necessary to make the piezoelectric actuator longer in the longitudinal direction and the size becomes large. 
     This problem is present not only in a liquid ejecting head ink that is represented by an ink jet recording head but also in the same manner in other piezoelectric devices. 
     SUMMARY 
     An advantage of some aspects of the invention is to provide a liquid ejecting head, a liquid ejecting apparatus, and a piezoelectric device which are capable of improving a displacement efficiency of a piezoelectric actuator with respect to the length thereof to obtain a reduction in size. 
     According to an aspect of the invention, a liquid ejecting head includes a flow path forming substrate in which a pressure generating chamber which communicates with a nozzle which ejects a liquid is formed by a partitioning wall, and a piezoelectric actuator in which a first electrode, a piezoelectric layer, and a second electrode are laminated, in which the piezoelectric layer includes a region which is interposed between the first electrode and the second electrode in a lamination direction, and in which when viewed in plan view from the lamination direction, the region overlaps at least a portion of the edges of each side of an opening of the pressure generating chamber on the piezoelectric actuator side and does not overlap one of the first electrode and the second electrode in at least a portion of the opening. 
     In this configuration, by providing the region which is interposed between the first electrode and the second electrode to overlap at least a portion of the edges of each side of the opening of the pressure generating chamber on the piezoelectric actuator side, it is possible to improve the displacement efficiency of the piezoelectric actuator with respect to the length of the pressure generating chamber. Therefore, even if the length of the pressure generating chamber is shortened and the length of the piezoelectric actuator is shortened, it is possible to suppress a reduction in the displacement characteristics, it is possible to reduce the size of the flow path forming substrate, and it is possible to dispose many pressure generating chambers and realize an increase in the number of nozzles. 
     Here, it is preferable that the opening be a parallelogram when viewed in plan view from the lamination direction. Accordingly, it is possible to easily dispose the nozzle communicating path, the supply path, and the like which communicate with the pressure generating chamber. 
     It is preferable that in at least a portion of the opening, a portion which does not overlap one of the first electrode and the second electrode have the same shape as the opening with a narrower area than the opening. Accordingly, it is possible to easily deform the piezoelectric actuator which faces the opening. 
     It is preferable that when viewed in plan view from the lamination direction, the region be provided to overlap an entirety of the edges of the opening. Accordingly, it is possible to easily perform the leading out of the individual electrode from the region. 
     It is preferable that a portion at which the first electrode and the second electrode do not overlap each other does not include the first electrode and the piezoelectric layer in at least a portion. Accordingly, it is possible to suppress the hindrance, caused by the piezoelectric layer, of the deformation of the portion which the first electrode and the second electrode do not overlap to easily deform the portion, and it is possible to easily deform the piezoelectric actuator. 
     It is preferable that a portion at which the first electrode and the second electrode do not overlap each other be provided at a center of the opening. Accordingly, it is possible to easily deform the piezoelectric actuator which faces the opening. 
     It is preferable that when viewed in plan view from the lamination direction, the nozzle be disposed on an outside of the region and on an inside of the pressure generating chamber. Accordingly, by setting the region which is interposed between the first electrode and the second electrode of the piezoelectric layer to a position which does not overlap the nozzle, the overlapping amount of the region over the partitioning wall is restricted, an excessive increase in the electrical capacitance of the piezoelectric actuator is suppressed, and it is possible to reduce the power consumption. When viewed in plan view from the lamination direction, by disposing the nozzle on the inside of the pressure generating chamber, it is possible to suppress an increase in the sizes of the flow path forming substrate and the nozzle plate. 
     It is preferable that the pressure generating chamber communicate with the nozzle on an opposite side from the piezoelectric actuator in the lamination direction, and that at least a portion of openings of the pressure generating chamber on the nozzle side does not overlap the region. Accordingly, the pressure generating chamber is provided to widen toward the opening on the nozzle side, it is possible to reduce the size of the opening of the pressure generating chamber on the piezoelectric actuator side and to obtain a reduction in size while securing the space to form the region which is interposed between the first electrode and the second electrode of the piezoelectric layer, and it is possible to increase the size of the opening of the pressure generating chamber on the nozzle side and to secure the necessary volume for the pressure generating chamber. 
     It is preferable that the opening of the pressure generating chamber on the opposite side from the piezoelectric actuator in the lamination direction be a parallelogram and a nozzle communicating path which communicates with the nozzle and a supply path which supplies a liquid to the pressure generating chamber be connected at each acute angle corner portion of the parallelogram. Accordingly, by connecting the nozzle communicating path and the supply path on the respective acute angle corner portions of the pressure generating chamber, it is possible to suppress the retention of the ink at the acute angle corner portions and to suppress the occurrence of ejection faults of the liquid caused by bubbles which are included in the liquid being retained at the acute angle corner portions. 
     It is preferable that multiple rows of the pressure generating chambers which are provided to line up in a first direction perpendicular to the lamination direction be formed in a second direction perpendicular to both the lamination direction and the first direction, and that the rows of pressure generating chambers which are provided in the second direction be disposed at different positions in the first direction. Accordingly, it becomes possible to dispose the nozzles at high density. 
     It is preferable that the pressure generating chamber include an inclined surface which is inclined in a direction widening to an opposite side from the piezoelectric actuator with respect to the lamination direction, and that when viewed in plan view from the lamination direction, an end portion of the region overlap the inclined surface. Accordingly, by providing an end portion of the region which is interposed between the first electrode and the second electrode of the piezoelectric layer on the inclined surface, it is possible to cause the boundary between the region which drives the piezoelectric actuator and the region which does not drive the piezoelectric actuator to be positioned on the inclined surface and to alleviate the stress of the boundary portion between the driving region and the non-driving region by the portion at which the inclined surface is formed deforming. Therefore, it is possible to suppress the occurrence of stress focusing at the boundary between the driving region and the non-driving region and to suppress destruction. 
     It is preferable that when viewed in plan view from the lamination direction, a width which overlaps the partitioning wall of the region in a normal line direction of the sides of the opening be greater than or equal to a thickness of the piezoelectric layer in the lamination direction and less than or equal to 10 μm. Accordingly, by setting the width of the region which is interposed between the first electrode and the second electrode of the piezoelectric layer to be greater than or equal to the thickness of the piezoelectric layer, it is possible to suppress the approaching of the boundary between the driving region on the partitioning wall and the non-driving region on the partitioning wall to an edge portion of the opening of the pressure generating chamber and to suppress destruction caused by stress at the boundary between the driving region on the partitioning wall and the non-driving region on the partitioning wall. By setting the width of the region which is interposed between the first electrode and the second electrode of the piezoelectric layer to less than or equal to 10 μm, it is possible to suppress an increase in the electrical capacitance of the piezoelectric actuator and an increase in the power consumption. 
     It is preferable that when viewed in plan view from the lamination direction, a width in which the region is provided to straddle an edge of the opening be in a range which is greater than or equal to 0.2 times and less than or equal to 0.5 times a width of the pressure generating chamber in a short direction. Accordingly, by defining the driving region which is interposed between the first electrode and the second electrode of the piezoelectric layer, it is possible to optimize the displacement efficiency of the piezoelectric actuator. 
     It is preferable that when viewed in plan view from the lamination direction, in at least a portion of the opening, a recessed portion which is open to an opposite side from the flow path forming substrate be provided in the piezoelectric layer of a portion which one of the first electrode and the second electrode does not overlap, and a width of the recessed portion in a short direction of the pressure generating chamber be in a range of greater than or equal to 0.1 times and less than or equal to 0.5 times a width of the pressure generating chamber. Accordingly, by defining the width of the recessed portion of the piezoelectric layer, it is possible to optimize the displacement efficiency of the piezoelectric actuator. 
     It is preferable that the piezoelectric actuator be formed on the flow path forming substrate via a diaphragm, and that a thickness of the diaphragm at a portion which one of the first electrode and the second electrode does not overlap in at least a portion of the opening in the lamination direction be thinner than the thickness of the diaphragm at the region. Accordingly, by reducing the thickness of the diaphragm at the portion which one of the first electrode and the second electrode does not overlap, the displacement of the portion becomes easy and it is possible to easily displace the piezoelectric actuator. 
     It is preferable that the piezoelectric layer be formed at a portion which one of the first electrode and the second electrode does not overlap in at least a portion of the opening. Accordingly, it is possible to suppress destruction which is caused by the displacement of the piezoelectric actuator. 
     According to another aspect of the invention, a liquid ejecting apparatus includes the liquid ejecting head of the above-described configuration. 
     In this configuration, it is possible to realize a liquid ejecting apparatus which is reduced in size. 
     Here, it is preferable to further include a control unit which supplies a drive signal, which includes an expanding element which charges the piezoelectric actuator to cause the pressure generating chamber to expand and a contracting element which discharges the piezoelectric actuator to cause the pressure generating chamber to contract, and causes a liquid to be ejected from the nozzle. Accordingly, since the internal stress of the piezoelectric layer is compressive stress in the expanding element, the destruction of the piezoelectric layer does not occur easily. Since the internal stress of the piezoelectric layer is only released in the contracting element, the destruction does not occur easily. 
     It is preferable that a potential difference of the expanding element be smaller than a potential difference of the contracting element. Accordingly, it is possible to further suppress the destruction of the piezoelectric layer. 
     According to still another aspect of the invention, a piezoelectric device includes a substrate in which a space is formed by a partitioning wall, and a piezoelectric actuator in which a first electrode, a piezoelectric layer, and a second electrode are laminated, in which the piezoelectric layer includes a region which is interposed between the first electrode and the second electrode in a lamination direction, and in which when viewed in plan view from the lamination direction, the region overlaps at least a portion of the edges of each side of an opening of the space on the piezoelectric actuator side and one of the first electrode and the second electrode does not overlap at least a portion of the opening. 
     In this configuration, by providing the region which is interposed between the first electrode and the second electrode to overlap at least a portion of the edges of each side of the opening of the space on the piezoelectric actuator side, it is possible to improve the displacement efficiency of the piezoelectric actuator with respect to the length of the space. Therefore, even if the length of the space is shortened and the length of the piezoelectric actuator is shortened, it is possible to suppress a reduction in the displacement characteristics, it is possible to reduce the size of the substrate, and it is possible to dispose many spaces. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIG. 1  is a diagram illustrating the schematic configuration of a recording apparatus according to a first embodiment of the invention. 
         FIG. 2  is an exploded perspective diagram of a recording head according to the first embodiment of the invention. 
         FIG. 3  is a plan view of a flow path forming substrate of the recording head according to the first embodiment of the invention. 
         FIG. 4  is an enlarged plan view of the main portions of the flow path forming substrate according to the first embodiment of the invention. 
         FIG. 5  is a sectional diagram of the recording head according to the first embodiment of the invention. 
         FIG. 6  is an enlarged sectional diagram of the main portions of the recording head according to the first embodiment of the invention. 
         FIG. 7  is an enlarged sectional diagram of the main portions of the recording head according to the first embodiment of the invention. 
         FIG. 8  is a block diagram illustrating the control configuration of the recording apparatus according to the first embodiment of the invention. 
         FIG. 9  is a drive waveform illustrating a drive signal according to the first embodiment of the invention. 
         FIG. 10  is a diagram illustrating an operation of a piezoelectric actuator according to the first embodiment of the invention. 
         FIG. 11  is a diagram illustrating an operation of the piezoelectric actuator according to the first embodiment of the invention. 
         FIG. 12  is a diagram illustrating an operation of the piezoelectric actuator according to the first embodiment of the invention. 
         FIG. 13  is an enlarged sectional diagram of the main portions of a recording head according to a second embodiment of the invention. 
         FIG. 14  is an enlarged sectional diagram of the main portions of a recording head according to a third embodiment of the invention. 
         FIG. 15  is a sectional diagram of a recording head according to a fourth embodiment of the invention. 
         FIG. 16  is a sectional diagram of a recording head according to another embodiment. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, a detailed description will be given of the invention based on the embodiments. 
     First Embodiment 
       FIG. 1  a diagram illustrating the schematic configuration of an ink jet recording apparatus which is an example of the liquid ejecting apparatus according to the first embodiment of the invention. 
     As illustrated, an ink jet recording apparatus I includes an ink jet recording head  1  (hereinafter also referred to as the recording head  1 ) which discharges an ink as a liquid. The recording head  1  is mounted on a carriage  3  and the carriage  3  is provided on a carriage shaft  5  which is attached to an apparatus main body  4  such that the carriage  3  is capable of moving in an axial direction of the carriage shaft  5 . An ink cartridge  2  which configures a liquid supply unit is provided in the carriage  3  to be attachable and detachable. 
     The carriage  3  to which the recording head  1  is mounted moves along the carriage shaft  5  due to the driving force of a drive motor  6  being transmitted to the carriage  3  via a plurality of gears (not illustrated) and a timing belt  7 . Meanwhile, the apparatus main body  4  is provided with a transport roller  8  as a transport unit and a recording sheet S, which is a medium such as paper on which the ink lands, is transported by the transport roller  8 . The transport unit which transports the recording sheet S is not limited to being a transport roller and may be a belt, a drum, or the like. In the present embodiment, a transport direction of the recording sheet S is referred to as a first direction X. The movement direction of the carriage  3  along the carriage shaft  5  is referred to as a second direction Y. A direction intersecting both the first direction X and the second direction Y is referred to as a third direction Z in the present embodiment. In the present embodiment, the relationship between the directions (X, Y, and Z) is perpendicular; however, the dispositional relationship of the components is not necessarily limited to being perpendicular. 
     In the ink jet recording apparatus I, so-called printing is performed by causing the ink to land across substantially the entire surface of the recording sheet S by causing ink droplets to be discharged from nozzles of the recording head  1  while transporting the recording sheet S in the first direction X with respect to the recording head  1  and causing the carriage  3  to move in the second direction Y with respect to the recording sheet S. 
     Here, a description will be given of an example of the recording head  1  which is mounted in the ink jet recording apparatus I with reference to  FIGS. 2 to 4 .  FIG. 2  is an exploded perspective diagram of an ink jet recording head which is an example of the liquid ejecting head according to the first embodiment of the invention,  FIG. 3  is a plan view of the flow path forming substrate of the ink jet recording head,  FIG. 4  is an enlarged diagram of the main portions of  FIG. 3 ,  FIG. 5  is a sectional diagram taken along an V-V line of  FIG. 3 ,  FIG. 6  is an enlarged sectional diagram of the main portions of  FIG. 5 , and  FIG. 7  is a sectional diagram taken along a VII-VII line of  FIG. 3 . In the present embodiment, a description of the directions of the recording head  1  will be given based on the directions when the ink jet recording apparatus I is mounted, that is, based on the first direction X, the second direction Y, and the third direction Z. Naturally, the disposition of the recording head  1  inside the ink jet recording apparatus I is not limited to the disposition which is illustrated hereinafter. 
     As illustrated, a plurality of pressure generating chambers  12  which are formed by partitioning walls  11  are formed in a flow path forming substrate  10  which configures the ink jet recording head  1  (hereinafter also referred to as the recording head  1 ) which is an example of the liquid ejecting head of the present embodiment. The plurality of pressure generating chambers  12  is provided to line up along the first direction X in which a plurality of nozzles  21  which discharge the same color of ink are provided to line up. In the flow path forming substrate  10 , in the second direction Y, multiple rows of the pressure generating chambers  12  are provided to line up in the first direction X and four rows are provided in the present embodiment. In the present embodiment, the rows of pressure generating chambers  12  which are provided to line up in the second direction Y are disposed at the same position in the first direction X. 
     The flow path forming substrate  10  of the present embodiment is formed of a silicon monocrystalline substrate having a surface with a crystalline plane azimuth of (100). The pressure generating chambers  12  are formed by subjecting the flow path forming substrate  10  to anisotropic etching from one surface side. In the present embodiment, as illustrated in  FIG. 5 , by subjecting the flow path forming substrate  10  which is formed of the monocrystalline substrate having a surface with a crystalline plane azimuth of (100) to anisotropic etching, the second direction Y side surfaces of the pressure generating chambers  12  form inclined surfaces  13  which are inclined with respect to the third direction Z such that the widths of the pressure generating chambers  12  become narrower toward a piezoelectric actuator  300  side. Incidentally, as illustrated in  FIGS. 4 and 6 , the side surfaces of the pressure generating chambers  12  in the second direction Y are surfaces which run along the third direction Z. By rendering the side surfaces of the pressure generating chambers  12  in the second direction Y surfaces which are parallel to the third direction Z, it is possible to dispose the pressure generating chambers  12  at high density in the first direction X. 
     As illustrated in  FIG. 4 , an opening  12   a  in the pressure generating chamber  12  on the piezoelectric actuator  300  side is a parallelogram when viewed in plan view from the third direction Z and an opening  12   b  in the pressure generating chamber  12  on the opposite side from the piezoelectric actuator  300 , the nozzle  21  side in the present embodiment, is a parallelogram when viewed in plan view from the third direction Z. However, the opening  12   a  and the opening  12   b  of the pressure generating chamber  12  are disposed such that the corner portions which have an acute angle are reversed. In the present embodiment, the pressure generating chambers  12  are formed such that the length in the second direction Y is longer than the width in the first direction X. In other words, the pressure generating chambers  12  are formed such that the first direction X is a short direction and the second direction Y is a longitudinal direction. In other words, the length in the second direction Y is the length of the opening  12   b  in the piezoelectric actuator  300  side. Naturally, the configuration is not limited thereto, and the pressure generating chambers  12  may be configured such that the first direction X is the longitudinal direction and the second direction Y is the short direction. The pressure generating chambers  12  may be provided such that the length of the first direction X is the same as the length of the second direction Y. 
     In this manner, by causing the pressure generating chamber  12  to widen toward the nozzle  21 , it is possible to reduce the size of the opening  12   a  of the pressure generating chamber  12  and obtain a reduction in size and an increase in density while securing the space which forms an active portion  310  (described later), and it is possible to increase the size of the opening  12   b  and secure the necessary volume for the pressure generating chamber  12 . 
     A communicating plate  15  and a nozzle plate  20  are sequentially laminated onto the first surface side of the flow path forming substrate  10  in the third direction Z as illustrated in  FIG. 5 . 
     A manifold  16  which communicates with every two rows of the rows of pressure generating chambers  12  which are provided to line up in the first direction X is provided in the communicating plate  15 . In other words, in the present embodiment, since four rows of the pressure generating chambers  12  are provided in the flow path forming substrate  10 , a total of two of the manifolds  16  which communicate with every two rows of the pressure generating chambers  12  are provided. 
     The manifold  16  has a recessed shape which is open to the nozzle plate  20  side of the communicating plate  15  without penetrating the communicating plate  15  in the third direction Z. As illustrated in  FIGS. 3 and 5 , when viewed in plan view from the third direction Z, the manifold  16  is formed at a position which straddles and overlaps the two rows of pressure generating chambers  12  which communicate in the second direction Y. Incidentally, the length of the manifold  16  in the second direction Y is shorter than the length of the two rows of the pressure generating chambers  12  in the second direction Y. Although described later in detail, this is because a nozzle communicating path  19  which communicates the pressure generating chamber  12  with the nozzle  21  is provided on the outside of the manifold  16  in the second direction Y. When viewed in plan view from the third direction Z, the manifold  16  is provided to be continuous across the first direction X of the two rows of pressure generating chambers  12  which are communicated. The manifold  16 , in the first direction X, is provided to extend to the outside of both end portions of the rows of pressure generating chambers  12 , and the ink is introduced via inlets (refer to  FIG. 2 ) which are provided in the communicating plate  15  at both end portions which are provided to extend. 
     As illustrated in  FIG. 5 , a supply path  18  which communicates with the manifold  16  and one end portion of the pressure generating chamber  12  in the second direction is provided in the communicating plate  15  independently for each of the pressure generating chambers  12 . The supply path  18  is provided to penetrate in the third direction Z so as to communicate the bottom surface of the manifold  16  on the pressure generation chamber  12  side and the bottom surface of the pressure generation chamber  12  on the manifold  16  side. In the present embodiment, as illustrated in  FIG. 4 , in the two rows of pressure generating chambers  12  which communicate with the single common manifold  16 , the supply paths  18  are provided to be open to an acute angle corner portion of one pressure generating chamber  12  on the other pressure generating chamber  12  side and an acute angle corner portion of the other pressure generating chamber  12  on the one pressure generating chamber  12  side. In other words, the supply paths  18  are disposed at the acute angle corner portions of the inside of the two rows of pressure generating chambers  12  in the second direction Y. 
     The nozzle communicating paths  19  which communicate the pressure generating chambers  12  with the nozzles  21  are provided in the communicating plate  15 . The nozzle communicating paths  19  are provided independently for each of the pressure generating chambers  12 . The nozzle communicating paths  19  are provided to penetrate the communicating plate  15  in the third direction Z. In the present embodiment, in the two rows of pressure generating chambers  12  which communicate with the single common manifold  16 , the nozzle communicating paths  19  are provided at the acute angle corner portion of the opposite side of the one pressure generating chamber  12  from the other pressure generating chamber  12  and the acute angle corner portion of the opposite side of the other pressure generating chamber  12  from the one pressure generating chamber  12 . In other words, the nozzle communicating paths  19  are disposed at the acute angle corner portions of the outside of the two rows of pressure generating chambers  12  in the second direction Y. In other words, in the opening  12   b  which is a parallelogram of the pressure generating chamber  12  on the communicating plate  15  side, the supply paths  18  are provided to be open at one corner portion of two the acute angle corner portions, and the nozzle communicating paths  19  are provided to be open at the other corner portion. In the two rows of pressure generating chambers  12 , the supply paths  18  are open to each of the acute angle corner portions of the inside of the second direction Y, and the nozzle communicating paths  19  are provided to be open to each of the acute angle corner portions of the outside of the second direction Y. Therefore, the nozzle communicating paths  19  which communicate with each of the rows of pressure generating chambers  12  are disposed at different positions in the first direction X in the two rows of pressure generating chambers  12  which communicate the single common manifold  16 . 
     In this manner, by providing the supply paths  18  and the nozzle communicating paths  19  on the respective acute angle corner portions of the openings  12   b  which are parallelograms of the pressure generating chambers  12 , it is possible to suppress the retention of the ink at the acute angle corner portions in the pressure generating chambers  12  and to suppress the occurrence of discharge faults of the ink droplets caused by bubbles which are included in the ink being retained at the acute angle corner portions. In other words, by providing the supply paths  18  and the nozzle communicating paths  19  on the respective acute angle corner portions of the openings  12   b  which are parallelograms of the pressure generating chambers  12 , it is possible to improve the bubble discharging properties. Incidentally, in a case in which the supply paths  18  and the nozzle communicating paths  19  are provided to communicate with the oblique corner portions or the like other than the acute angle corner portions of the openings  12   b  which are parallelograms of the pressure generating chambers  12 , for example, there is a concern that the ink will be retained at the acute angle corner portions, the bubbles which are included in the ink will be retained at the acute angle corner portions and grow, the pressure fluctuations of the driving of the piezoelectric actuators  300  will be absorbed by the bubbles, and discharge faults of the ink droplets will occur. 
     The nozzles  21  which communicate with each of the pressure generating chambers  12  via the nozzle communicating paths  19  are formed in the nozzle plate  20 . The nozzles  21  which eject the ink (the liquid) of the same type are provided line up in the first direction X to configure a nozzle row. Four nozzle rows which are configured by the nozzles  21  which are provided to line up in the first direction X are formed in the second direction Y. As described above, in the two rows of pressure generating chambers  12  which communicate with the single common manifold  16 , since the nozzle communicating paths which communicate with one row of pressure generating chambers  12  are disposed at positions which are different in the first direction X from the nozzle communicating paths  19  which communicate with the other row of pressure generating chambers  12 , the nozzle communicating paths  19  are also disposed at positions which are different in the first direction X at the nozzles  21  which communicate with the nozzle communicating paths  19 . In other words, in the nozzle plate  20 , two rows are provided to line up in the second direction Y, each of the rows having the nozzles  21  which communicate with the single common manifold  16  provided to line up in the first direction X, and the rows of nozzles  21  which are provided at different positions in the second direction Y are disposed to be shifted alternately in the first direction X. Accordingly, the nozzles  21  are disposed in a so-called zig-zag pattern along the first direction X. In this manner, it is possible to dispose the nozzles  21  at high density in the first direction X without disposing the two rows of pressure generating chambers  12  in the first direction X by rendering the openings  12   b  of the two rows of pressure generating chambers  12  parallelograms and causing the nozzle communicating paths  19  to communicate with the acute angle corner portions which have different positions in the first direction X. Therefore, it is possible to obtain a reduction in the size of the flow path forming substrate  10  and an increase in density of the nozzles  21 . It is possible to increase the distance in the second direction Y between the nozzle communicating paths  19  which communicate the two rows of pressure generating chambers  12  by forming the pressure generating chambers  12  to widen toward the nozzles  21  in the third direction Z and causing the nozzle communicating paths  19  to open to the corresponding acute angle corner portions of the outside of the two rows of pressure generating chambers  12 . Therefore, it is possible to dispose the manifold  16  between the two nozzle communicating paths  19  such that the manifold  16  is large in the second direction Y. 
     The openings of the manifold  16  on the opposite side from the pressure generating chambers  12  are sealed by the nozzle plate  20 . A recessed portion  22  which is open to the manifold  16  side is provided in the nozzle plate  20  in the region which seals the openings of the manifold  16 . By providing the recessed portion  22  in the nozzle plate  20  in this manner, the region which seals the manifold  16  o the nozzle plate  20  forms a compliance portion  23  which is a flexible portion which has a thinner thickness than the other regions. By providing the compliance portion  23  in the wall which forms the manifold  16  in this manner, it is possible to absorb the pressure fluctuations inside the manifold  16  through the deformation of the compliance portion  23 . 
     Meanwhile, a diaphragm  50  is formed on the opposite surface side of the flow path forming substrate  10  from the communicating plate  15 . In the present embodiment, an elastic film  51  which is provided on the flow path forming substrate  10  side and is formed of silicon oxide and an insulating film  52  which is provided on the elastic film  51  and is formed from zirconium oxide are provided as the diaphragm  50 . The liquid flow path of the pressure generating chamber  12  or the like is formed by subjecting the flow path forming substrate  10  to anisotropic etching from the side of the surface to which the nozzle plate  20  is bonded, and the other surface of the pressure generating chamber  12  is formed by being partitioned by the elastic film  51 . Naturally, the diaphragm  50  is not particularly limited thereto, and the diaphragm  50  may be provided on either one of the elastic film  51  and the insulating film  52 , or another film may be provided. 
     The piezoelectric actuator  300  is provided on the diaphragm  50  of the flow path forming substrate  10  as a drive element which generates pressure changes in the ink inside the pressure generating chamber  12  of the present embodiment. 
     The piezoelectric actuator  300  includes a first electrode  60 , a piezoelectric layer  70 , and a second electrode  80  which are sequentially laminated in the third direction Z from the diaphragm  50  side. In other words, the lamination direction of the first electrode  60 , the piezoelectric layer  70 , and the second electrode  80  is the third direction Z. 
     Displacement is generated in the piezoelectric actuator  300  which is configured by the first electrode  60 , the piezoelectric layer  70 , and the second electrode  80  by applying a voltage between the first electrode  60  and the second electrode  80 . In other words, piezoelectric strain is generated in the piezoelectric layer  70  which is interposed between the first electrode  60  and the second electrode  80  by applying a voltage between both electrodes. When a voltage is applied to both electrodes, a portion where piezoelectric strain is generated in the piezoelectric layer  70 , that is, a region which is interposed between the first electrode  60  and the second electrode  80  in the third direction Z which is the lamination direction is referred to as the active portion  310 . In comparison, a portion where piezoelectric strain is not generated in the piezoelectric layer  70 , that is, a region which is not interposed between the first electrode  60  and the second electrode  80  in the third direction Z which is the lamination direction is referred to as an inactive portion. In the present embodiment, in the piezoelectric actuator  300 , a portion at which either one of the first electrode  60  and the second electrode  80  does not overlap in the third direction Z is referred to as a non-drive portion. In other words, the non-drive portion refers to a portion in which either one of the first electrode  60  and the second electrode  80  is not formed or a portion in which both the first electrode  60  and the second electrode  80  are not formed and only the piezoelectric layer  70  is formed. In other words, the non-drive portion includes a portion in which the inactive portion of the piezoelectric layer  70  or the piezoelectric layer  70  is not formed and only one of the first electrode  60  and the second electrode  80  is formed. 
     In the present embodiment, although described later in detail, the active portion  310  which is a region of the piezoelectric layer  70  which is interposed between the first electrode  60  and the second electrode  80  is formed independently for each of the pressure generating chambers  12 . In other words, a plurality of the active portions  310  is formed on the flow path forming substrate  10  (on the diaphragm  50 ). Generally, one of the electrodes of the active portion  310  is a common electrode which is shared by a plurality of the active portions  310  and the other electrode is configured as an individual electrode which is independent for each of the active portions  310 . In the present embodiment, the first electrode  60  is an individual electrode and the second electrode  80  is a common electrode; however, the opposite configuration may be adopted. In other words, in the present embodiment, the first electrode  60  is set to the individual electrode by providing the first electrodes  60  independently for each of the plurality of active portions  310  and the second electrode  80  is set to the common electrode by providing the second electrode  80  continuously along the plurality of active portions  310 ; however, the first electrode  60  may be set to the common electrode by providing the first electrode  60  continuously along the plurality of active portions  310  and the second electrode  80  may be set to the individual electrode by providing the second electrodes  80  independently for each of the plurality of active portions  310 . In the example which is described above, the diaphragm  50  and the first electrode  60  act as a diaphragm; however, naturally, the configuration is not limited thereto, and, for example, a configuration may be adopted in which only the first electrode  60  acts as the diaphragm without providing the diaphragm  50 . The piezoelectric actuator  300  itself may also function effectively as the diaphragm. 
     Here, a more detailed description will be given of the piezoelectric actuator  300  of the present embodiment. The first electrode  60  which configures the piezoelectric actuator  300  is cut and divided for each of the pressure generating chambers  12  and configures an individual electrode which is independent for each of the active portions  310  which are the effective drive portions of the piezoelectric actuators  300 . 
     Specifically, as illustrated in  FIGS. 4, 6, and 7 , the first electrodes  60  which define the active portions are provided such that at least a portion overlaps the sides of the openings of the pressure generating chambers  12  on the piezoelectric actuator  300  side, that is, the openings of the parallelograms in plan view of the third direction Z. In other words, the first electrodes  60  are formed to straddle over the partitioning walls  11  which form the pressure generating chambers  12  of the flow path forming substrate  10  and over the regions facing the pressure generating chambers  12  (inside the openings of the pressure generating chambers  12 ) at the sides of the openings including the parallelograms of the pressure generating chambers  12  on the piezoelectric actuator  300  side. In the present embodiment, the first electrode  60  is provided to overlap the entirety of the edges of the opening of the pressure generating chamber  12  on the piezoelectric actuator  300  side when viewed in plan view from the third direction Z. 
     The first electrodes  60  of the present embodiment are not provided in at least a portion of the openings of the pressure generating chambers  12  on the piezoelectric actuator  300  side. In the present embodiment, when viewed in plan view from the third direction Z, the first electrode  60  is formed such that the width thereof in the normal line direction of the sides of the opening of the pressure generating chamber  12  on the piezoelectric actuator  300  side is the same width toward a direction along the sides, and the first electrode  60  is not formed at the center portion of the opening of the pressure generating chamber  12  on the piezoelectric actuator  300  side. 
     The piezoelectric layer  70  is formed of an oxide piezoelectric material which is formed on the first electrode  60  and has a polarized structure, for example, it is possible to form the piezoelectric layer  70  of a perovskite-type oxide which is illustrated by general formula ABO 3 . It is possible to use a lead-based piezoelectric material which contains lead, a non lead-based piezoelectric material which does not contain lead, or the like, for example, as the perovskite-type oxide which is used in the piezoelectric layer  70 . 
     In the present embodiment, as illustrated in  FIGS. 6 and 7 , the piezoelectric layer  70  is provided independently for each of the pressure generating chambers  12 , that is, for each of the active portions  310 . The piezoelectric layer  70  has a size which is large enough to cover the end portions of the first electrode  60  excluding the portion which leads out. In the present embodiment, a recessed portion  71  is formed in a portion (a non-drive portion  311 ) in which the first electrode  60  is not formed in the center portion of the opening of the pressure generating chamber  12  of the piezoelectric layer  70  on the piezoelectric actuator  300  side. 
     In the present embodiment, the piezoelectric layer  70  is cut up and provided independently for each of the active portions  310 ; however, the configuration is not particularly limited thereto, and the piezoelectric layer  70  may be provided continuously across the plurality of active portions  310 . 
     The second electrode  80  is provided on the opposite surface side of the piezoelectric layer  70  from the first electrode  60  and configures a common electrode which is shared by the plurality of active portions  310 . In the present embodiment, the second electrode  80  is provided continuously across the plurality of active portions  310  on the piezoelectric layer  70  and on the diaphragm  50 . The second electrode  80  is provided continuously on the inside of the recessed portion  71  of the piezoelectric layer  70 , that is, across the side surface of the recessed portion  71  and on the diaphragm  50  inside the recessed portion  71 . As described above, by forming the second electrode on the piezoelectric layer  70  and on the diaphragm  50 , the second electrode  80  is formed closer to the outside of the first electrode  60  than the end portions. Therefore, the active portion  310  of the present embodiment is defined by the first electrode  60 . However, as illustrated in  FIG. 3 , the second electrode  80  is not formed on the portion which leads out the first electrode  60  from the active portion  310 , and the active portion  310  is defined by the second electrode  80  in this portion. 
     In the piezoelectric actuator  300  having the first electrode  60 , the piezoelectric layer  70 , and the second electrode  80 , the portion in which the first electrode  60  is provided forms the active portion  310  and the portion in which the first electrode  60  is not formed and either one or both of the piezoelectric layer  70  and the second electrode  80  are not provided forms non-drive portions  311  and  312 . In the present embodiment, the active portion  310  is provided to overlap the entirety of the edges of the opening of the pressure generating chamber  12  on the piezoelectric actuator  300  side of the parallelogram when viewed in plan view from the third direction Z. In other words, the active portions  310  are formed to straddle over the partitioning walls  11  which form the pressure generating chambers  12  of the flow path forming substrate  10  and over the regions facing the pressure generating chambers  12  (inside the openings of the pressure generating chambers  12 ) at the sides of the openings including the parallelograms of the pressure generating chambers  12  on the piezoelectric actuator  300  side. 
     As illustrated in  FIG. 4 , by not forming the first electrode  60  at the center portion of the opening  12   a  of the pressure generating chamber  12  on the piezoelectric actuator  300  side, the non-drive portion  311  at which the first electrode  60  and the second electrode  80  do not overlap each other is formed at this portion. The first electrode  60  which defines the active portion  310  of the present embodiment is formed such that the width in the normal line direction of the sides of the opening  12   a  of the pressure generating chamber  12  on the piezoelectric actuator  300  side when viewed in plan view from the third direction Z is the same width toward a direction along the sides. Therefore, the non-drive portion  311  has the same shape as the opening  12   a , that is, is a parallelogram with a narrower area than the opening of the pressure generating chamber  12  of the piezoelectric actuator  300  side. As described above, the recessed portion  71  is formed in the piezoelectric layer  70  of the non-drive portion  311 . In other words, therefore, the hindrance of the deformation of the non-drive portion  311  by the piezoelectric layer  70  is suppressed, the non-drive portion  311  may deform more easily, and the active portion  310  may deform more easily. Incidentally, the non-drive portion  312  at which only the second electrode  80  is formed is present without the first electrode  60  being formed on the partitioning walls  11 . 
     As illustrated in  FIG. 3 , individual wirings  91  which are lead-out wirings are lead out from the first electrodes  60  which are the individual electrodes of each of the active portions  310 . In the present embodiment, the individual wirings  91  are lead out toward the center portion in the second direction Y of the flow path forming substrate  10 . 
     The second electrodes  80  are provided continuously at the portions other than the individual wirings  91 , and common wirings  92  are lead out from the second electrodes  80  toward the center portions in the second direction Y of the flow path forming substrate  10  at both sides in the first direction X of the active portions  310 . A flexible cable  120  is connected to the individual wirings  91  and the common wirings  92 . The flexible cable  120  is a flexible wiring substrate, and in the present embodiment, a drive circuit  121  which is a semiconductor element is installed. 
     As illustrated in  FIG. 5 , a protective substrate  30  is bonded to the surface of the flow path forming substrate  10  on the piezoelectric actuator  300  side. The protective substrate  30  includes a holding portion  31  which is a space for protecting the piezoelectric actuator  300 . Two of the holding portions  31  are formed to line up in the second direction Y, each being provided for one of the two rows of active portions  310  which are provided to line up in the first direction X. In other words, the two rows of active portions  310  are disposed inside the single holding portion  31 . A through hole  32  which penetrates the protective substrate  30  in the third direction Z is provided in the protective substrate  30  between the two holding portions  31  which are provided to line up in the second direction Y. The individual wirings  91  which are lead out from the first electrode  60  of the piezoelectric actuator  300  and the end portions of the common wirings  92  which are lead out from the second electrodes  80  are provided to extend to be exposed to the inside of the through holes  32  and are electrically connected to the flexible cable  120  inside the through holes  32 . 
     In the recording head  1 , when the ink is ejected, the ink is taken in from the inlets  17  and the inner portion of the flow paths from the manifolds  16  to the nozzles  21  are filled with the ink. Subsequently, by applying a voltage to each of the piezoelectric actuators  300  which correspond to the pressure generating chambers  12  according to the signals from the drive circuit  121 , the diaphragms  50  are caused to flex and deform together with the piezoelectric actuators  300 . Accordingly, the pressure inside the pressure generating chambers  12  increases and the ink droplets are ejected from the predetermined nozzles  21 . 
     As described above, the active portion  310  overlaps at least a portion of the edge of each of the sides of the opening  12   a  of the pressure generating chamber  12  on the piezoelectric actuator  300  side and has the non-drive portion  311  on at least a portion of the opening  12   a  when viewed in plan view from the third direction Z, and thus, it is possible to improve the displacement efficiency of the piezoelectric actuator  300  with respect to the length of the pressure generating chamber  12  in the second direction Y which is the longitudinal direction. Incidentally, in a case in which the active portion  310  of the piezoelectric actuator  300  is provided to not overlap the edge portions of the opening  12   a , that is, is provided at a position which overlaps the center portion of the pressure generating chamber  12  when viewed in plan view, in order to improve the displacement amount of the piezoelectric actuator  300 , it is necessary to lengthen the pressure generating chamber  12  in the second direction Y and to form the piezoelectric actuator  300  to be long in the second direction Y and the displacement efficiency of the piezoelectric actuator  300  is poor with respect to the length in the second direction Y. In the present embodiment, even if the length of the pressure generating chamber  12  in the second direction Y is shortened by providing the active portion  310  to overlap at least a portion of the edges of each of the sides of the opening  12   a , it is possible to suppress a reduction in the displacement characteristics. Therefore, it is possible to obtain a reduction in the size of the flow path forming substrate  10  and a reduction in the size of the recording head  1 . Since it is possible to shorten the length of the pressure generating chamber  12  in the second direction Y, it is possible to dispose a plurality of the rows of the pressure generating chambers  12 , which are provided to line up in the first direction X, in rows in the second direction Y, and it is possible to obtain a reduction in size and an increase in the number of nozzles. 
     In the present embodiment, the active portion  310  is provided to overlap the entirety of the edge of the opening  12   a  when viewed in plan view from the third direction Z. Therefore, it is possible to easily perform the pulling out and routing of the wiring from the individual electrode of the active portion  310 , in the present embodiment, from the first electrode  60 . Incidentally, in a case in which the active portion  310  is provided non-continuously at the edges of the opening  12   a , when the first electrode  60  is divided, the leading out of the wiring from the first electrode  60  increases and the routing of the individual wiring  91  becomes difficult. Therefore, in a case in which the active portion  310  is provided non-continuously at the edges of the opening  12   a , the first electrode  60  may be provided continuously at the edges of the opening  12   a , and the second electrode  80  may be provided such that a portion is non-continuous at the edges of the opening  12   a . In this case, it is possible to easily perform the leading out and the routing of the wiring from the first electrode  60  which is the individual electrode. 
     The opening  12   a  of the pressure generating chamber  12  on the piezoelectric actuator  300  side is a parallelogram when viewed in plan view from the third direction Z. In particular, it is possible to form the pressure generating chambers  12  with high precision and at high density by subjecting the monocrystalline silicon substrate which has a surface with a crystalline plane azimuth of (100) to anisotropic etching to form the pressure generating chambers  12 . 
     In the present embodiment, the active portion  310  is formed such that the width in the normal line direction of the sides of the opening  12   a  of the pressure generating chamber  12  on the piezoelectric actuator  300  side is the same width toward a direction along the sides when viewed in plan view from the third direction Z. Therefore, the non-drive portion  311  has the same shape as the opening  12   a , that is, is a parallelogram with a narrower area than the opening of the pressure generating chamber  12  on the piezoelectric actuator  300  side and is provided at the center portion of the opening  12   a . In this manner, by providing the non-drive portion  311  at the center portion of the opening  12   a  in the same shape as the opening  12   a , it is possible to cause the active portion  310  to deform easily. Naturally, the non-drive portion  311  may be the same shape as the opening  12   b  of the pressure generating chamber  12  and may be provided at a portion other than the center portion of the opening  12   a.    
     Since the active portion  310  and the non-drive portion  311  are defined by the first electrode  60 , the non-drive portion  311  does not include the first electrode  60 . The recessed portion  71  is provided in the piezoelectric layer  70  of the non-drive portion  311 . Therefore, at least a portion of the non-drive portion  311  does not include the first electrode  60  and the piezoelectric layer  70 . In this manner, due to at least a portion of the non-drive portion  311  not including the first electrode  60  and the piezoelectric layer  70 , the hindrance of the deformation of the non-drive portion  311  by the piezoelectric layer  70  is suppressed, the non-drive portion  311  may deform more easily, and the active portion  310  may deform more easily. 
     In the present embodiment, as illustrated in  FIG. 6 , when viewed in plan view from the third direction Z, the end portion of the active portion  310 , in the present embodiment, the end portion of the first electrode  60  is provided at a position which overlaps the inclined surface  13 . In this manner, by providing the end portion of the active portion  310  above the inclined surface  13  in the third direction Z, the boundary between the active portion  310  and the non-drive portion  312  is positioned above the inclined surface  13 . Since the thickness of the flow path forming substrate  10  in the third direction Z gradually increases toward the outside from the pressure generating chambers  12  due to the inclined surfaces  13 , the rigidity of the portions at which the inclined surfaces  13  of the flow path forming substrate  10  are provided gradually increases toward the outside from the pressure generating chambers  12 . Therefore, when the active portion  310  is driven, the stress of the boundary portion between the active portion  310  and the non-drive portion  312  is mitigated by the deformation of the inclined surface  13 . In particular, although the region in which the inclined surface  13  is provided deforms, since the rigidity of the flow path forming substrate  10  gradually increases from the pressure generating chamber  12  side toward the outside due to the inclined surface  13 , the flow path forming substrate  10  which is provided with the inclined surface  13  deforms more easily the closer to the active portion  310  side and deforms less easily the closer to the non-drive portion  312  side. Therefore, it is possible to effectively mitigate the focusing of stress between the active portion  310  and the non-drive portion  312  due to the deforming of the flow path forming substrate  10  which is provided with the inclined surface  13 , and it is possible to suppress the occurrence of stress focusing at the boundary between the active portion  310  and the non-drive portion  312  and to suppress the destruction. 
     Here, as illustrated in  FIG. 7 , when viewed in plan view from the third direction Z side, it is preferable that a width W 1  which overlaps the partitioning wall  11  of the first electrode  60  which defines the active portion  310  in the normal line direction of the side of the opening  12   a  of the pressure generating chamber  12  be greater than or equal to the thickness of the piezoelectric layer  70  in the third direction Z and less than or equal to 10 μm. For example, when the thickness of the piezoelectric layer  70  is thickened, the tensile stress which is the internal stress of the active portion  310  increases when the active portion  310  is driven. At this time, when the width W 1  of the first electrode  60  above the partitioning wall  11 , that is, the width W 1  of the active portion  310  above the partitioning wall  11  is narrow, the boundary between the active portion  310  and the non-drive portion  312  above the partitioning wall  11  approaches the edge portion of the opening of the pressure generating chamber  12  and there is a concern that destruction will occur at the boundary between the active portion  310  and the non-drive portion  312 . Therefore, it is preferable that the width W 1  of the active portion  310  above the partitioning wall  11  be greater than or equal to the thickness of the piezoelectric layer  70 . When the width W 1  of the first electrode  60 , that is, the active portion  310  above the partitioning wall  11  is too great, the capacity of the active portion  310  increases and the power consumption increases. Therefore, it is preferable that the width W 1  of the active portion  310  above the partitioning wall  11  be less than or equal to 10 μm. As illustrated in  FIG. 7 , the width W 1  which overlaps the partitioning wall  11  of the active portion  310  is not only the width with respect to the sides which are provided on both sides in the second direction Y, but also the same applies to the width with respect to the sides which are provided on both sides in the first direction X as illustrated in  FIG. 6 . 
     As illustrated in  FIG. 7 , when viewed in plan view from the third direction Z, it is preferable that a width W 2  in which the first electrode  60  which defines the active portion  310  is provided to straddle the opening  12   a  of the pressure generating chamber  12  be within a range of greater than or equal to 0.2 times and less than or equal to 0.5 times a width W c  of the pressure generating chamber  12  in the first direction X which is the short direction. As illustrated in  FIG. 7 , the width W 2  in which the active portion  310  straddles the opening  12   a  is not only the width with respect to the sides which are provided on both sides in the second direction Y, but also the same applies to the width with respect to the sides which are provided on both sides in the first direction X as illustrated in  FIG. 6 . 
     As illustrated in  FIG. 7 , when viewed in plan view from the third direction Z, it is preferable that the recessed portion  71  which is open to the opposite side from the flow path forming substrate  10  be provided in the piezoelectric layer  70  of the non-drive portion  311 , and that a width W 3  of the recessed portion  71  be within a range of greater than or equal to 0.1 times and less than or equal to 0.5 times the width W c  of the pressure generating chamber  12  in the first direction X which is the short direction of the pressure generating chamber  12 . It is possible to optimize the displacement efficiency of the active portion  310  by defining the width W 2  of the active portion  310  and the width W 3  of the recessed portion  71  of the piezoelectric layer  70  which is provided in the non-drive portion  311 . In other words, the displacement efficiency of the active portion is reduced by setting the active portion  310  and the non-drive portion  311  outside of the ranges described above. The width W 3  of the recessed portion  71  is the width at the opening portion on the opposite side from the flow path forming substrate  10 . As illustrated in  FIG. 7 , the width W 3  of the recessed portion  71  is not only the width between the sides which are provided on both sides in the second direction Y, but also the same applies to the width with respect to the sides which are provided on both sides in the first direction X as illustrated in  FIG. 6 . 
     As illustrated in  FIG. 4 , the active portion  310  is disposed at a position which does not overlap the nozzle  21  when viewed in plan view from the third direction Z. In other words, when viewed in plan view from the third direction Z, the nozzle  21  is disposed on the outside of the active portion  310  and the inside of the pressure generating chamber  12 . Due to the active portion  310  being set to a position which does not overlap the nozzle  21 , the overlapping amount of the active portion  310  above the partitioning wall  11  is restricted and it is possible to suppress the electrical capacitance of the active portion  310  from becoming too great and to reduce the power consumption. When viewed in plan view from the third direction Z, it is possible to suppress the increase in the sizes of the flow path forming substrate  10  and the nozzle plate  20  by disposing the nozzle  21  on the inside of the pressure generating chamber  12 , that is by disposing the nozzle  21  at a position which does not overlap the pressure generating chamber  12 . 
     In the present embodiment, the pressure generating chamber  12  communicates with the nozzle  21  on the opposite side from the piezoelectric actuator  300  in the third direction Z and the active portion  310  is disposed at a position at which at least a portion of the opening of the pressure generating chamber  12  on the nozzle  21  side does not overlap the active portion  310 . In other words, the pressure generating chamber  12  is provided to widen toward the opening  12   b  of the nozzle  21  side. In the present embodiment, the pressure generating chamber  12  widens toward the opening  12   b  of the nozzle  21  side due to the inclined surface  13 . In this manner, by causing the pressure generating chamber  12  to widen toward the nozzle  21  side, it is possible to reduce the size of the opening  12   a  of the pressure generating chamber  12  and to obtain a reduction in size while securing the space to form the active portion  310  and it is possible to increase the size of the opening  12   b  and secure the necessary volume for the pressure generating chamber  12 . 
     In the present embodiment, as illustrated in  FIG. 4 , in the third direction Z, in the pressure generating chamber  12 , the opening  12   b  of the opposite surface side from the piezoelectric actuator  300  is a parallelogram and the nozzle communicating path  19  which communicates with the nozzle  21  is connected to the supply path  18  which supplies the ink to the pressure generating chamber  12  at each of the acute angle corner portions of the parallelogram. In this manner, by connecting the nozzle communicating path  19  and the supply path  18  on the respective acute angle corner portions of the pressure generating chamber  12 , it is possible to suppress the retention of the ink at the acute angle corner portions and to suppress the occurrence of discharge faults of the ink droplets caused by bubbles which are included in the ink being retained at the acute angle corner portions. 
     It is possible to increase the distance in the second direction Y between the nozzle communicating paths  19  which communicate the two rows of pressure generating chambers  12  due to the pressure generating chambers  12  widening toward the nozzles  21  and by causing the nozzle communicating paths  19  to open to the corresponding acute angle corner portions of the outside of the two rows of pressure generating chambers  12  which communicate with the single common manifold  16 . Therefore, it is possible to dispose the manifold  16  which communicates in common with the two rows of pressure generating chambers  12  between the two nozzle communicating paths  19  such that the manifold  16  is large in the second direction Y. 
     As illustrated in  FIG. 1 , the ink jet recording apparatus I includes a control device  200 . Here, a description will be given of the electrical configuration of the ink jet recording apparatus I of the present embodiment with reference to  FIG. 8 .  FIG. 8  is a block diagram illustrating the control configuration of the ink jet recording apparatus according to the first embodiment of the present embodiment. 
     As illustrated in  FIG. 8 , the ink jet recording apparatus I is provided with a printer controller  210 , which is the control unit of the present embodiment, and a print engine  220 . 
     The printer controller  210  is an element which controls the entirety of the ink jet recording apparatus I, and in the present embodiment, is provided inside the control device  200  which is provided in the ink jet recording apparatus I. 
     The printer controller  210  is provided with an external interface  211  (hereinafter referred to as the external I/F  211 ), a RAM  212  which temporarily stores various data, a ROM  213  which stores control programs and the like, a control processing unit  214  which is configured to include a CPU and the like, an oscillating circuit  215  which generates a clock signal, a drive signal generating unit  216  which generates a drive signal for supplying to the recording head  1 , and an internal interface  217  (hereinafter referred to as the internal I/F  217 ) which transmits dot pattern data (bitmap data) which is expanded based on the drive signal and the print data to the print engine  220 . 
     The external I/F  211  receives the print data which is configured by character codes, graphic functions, image data, and the like, for example, from an external device  230  such as a host computer. Busy signals (BUSY) and acknowledgment signals (ACK) are output to the external device  230  through the external I/F  211 . 
     The RAM  212  functions as a reception buffer  212 A, an intermediate buffer  212 B, an output buffer  212 C, and a work memory (not illustrated). The reception buffer  212 A temporarily stores the print data which is received by the external I/F  211 , the intermediate buffer  212 B stores intermediate code data which is converted by the control processing unit  214 , and the output buffer  212 C stores dot pattern data. The dot pattern data is configured by printing data which is obtained by decoding (translating) gradation data. 
     In addition to control programs (control routines) for causing various data processes to be performed, the ROM  213  stores font data, graphic functions, and the like in advance. 
     The control processing unit  214  reads the print data in the reception buffer  212 A and causes the intermediate code data which is obtained by converting the print data to be stored in the intermediate buffer  212 B. The intermediate code data which is read from the intermediate buffer  212 B is analyzed and the intermediate code data is expanded into the dot pattern data with reference to the font data, graphic functions, and the like which are stored in the ROM  213 . The control processing unit  214  performs the necessary auxiliary processes and subsequently stores the expanded dot pattern data in the output buffer  212 C. 
     If one line worth of the dot pattern data is obtained by the recording head  1 , the one line worth of dot pattern data is output to the recording head  1  through the internal I/F  217 . When the one line worth of dot pattern data is output from the output buffer  212 C, the expanded intermediate code data is erased from the intermediate buffer  212 B and the expanding process is performed for the next item of intermediate code data. 
     The print engine  220  is configured to include the recording head  1 , a paper feed mechanism  221 , and a carriage mechanism  222 . The paper feed mechanism  221  is configured by the transport roller  8 , a motor (not illustrated) which drives the transport roller  8 , and the like and sequentially feeds out the recording sheet S in cooperation with the recording operation of the recording head  1 . In other words, the paper feed mechanism  221  moves the recording sheet S relative to the first direction X. The carriage mechanism  222  includes the carriage  3 , the drive motor  6  which causes the carriage  3  to move in the second direction Y along the carriage shaft  5 , and the timing belt  7 . 
     The recording head  1  is provided with the drive circuit  121  which includes a shift register  122 , a latch circuit  123 , a level shifter  124 , and a switch  125 , and the piezoelectric actuator  300 . The shift register  122 , the latch circuit  123 , the level shifter  124 , and the switch  125  generate an application pulse from the drive signal which is generated by the drive signal generating unit  216 . Here, the application pulse is actually applied to the piezoelectric actuator  300 . 
     Here, a description will be given of the drive signal which includes the drive waveform which is generated by the drive signal generating unit  216 .  FIG. 9  is a drive waveform illustrating the drive signal. 
     As illustrated in  FIG. 9 , a drive signal COM of the present embodiment is repeatedly generated from the drive signal generating unit  216  for every unit period T (the discharge period T) which is defined by the clock signal which is emitted from the oscillating circuit  215 . The unit period T corresponds to one pixel worth of the image or the like to be printed onto the recording sheet S. When one line worth (one raster worth) of the dot pattern is formed in the recording region of the recording sheet S during the printing, the drive signal is selectively applied to the piezoelectric actuator  300  corresponding to each of the nozzles  21 . In the present embodiment, the drive signal is supplied to the first electrode  60  which is the individual electrode using the second electrode  80  which is the common electrode of the piezoelectric actuator  300  as a reference potential (Vbs). In other words, the voltage which is applied to the first electrode  60  by the drive waveform is represented as the potential which is based on the reference potential (Vbs). 
     Specifically, the drive signal COM includes an expanding element P 1 , an expansion maintenance element P 2 , a contracting element P 3 , a contraction maintenance element P 4 , and an expanding recovery element P 5 . The expanding element P 1  charges from a reference potential Vm to a first potential V 1  to cause the volume of the pressure generating chamber  12  to expand from the reference volume, the expansion maintenance element P 2  maintains the volume of the pressure generating chamber  12  which is expanded by the expanding element P 1  for a fixed time, the contracting element P 3  discharges from the first potential V 1  to a second potential V 2  to cause the volume of the pressure generating chamber  12  to contract, the contraction maintenance element P 4  maintains the volume of the pressure generating chamber  12  which is contracted by the contracting element P 3  for a fixed time, and the expanding recovery element P 5  causes the pressure generating chamber  12  to recover from the contracted state of the second potential V 2  to the reference volume of the reference potential Vm. 
     In the present embodiment, the potential difference of the expanding element P 1 , that is, the potential difference between the reference potential Vm and the first potential V 1  is smaller than the potential difference of the contracting element P 3 , that is, the potential difference between the first potential V 1  and the second potential V 2 . 
     When the drive signal COM is supplied to the piezoelectric actuator  300 , by charging the piezoelectric actuator  300  with the reference potential Vm, as illustrated in  FIG. 10 , the pressure generating chamber  12  is expanded from the original volume to the reference volume. Next, by charging the piezoelectric actuator  300  with the expanding element P 1 , as illustrated in  FIG. 11 , the piezoelectric actuator  300  is caused to deform to the opposite side from the pressure generating chamber  12  and the pressure generating chamber  12  expands more from the reference volume. By discharging the piezoelectric actuator  300  using the contracting element P 3 , as illustrated in  FIG. 12 , the volume of the pressure generating chamber  12  contracts to the original volume (the non-charged volume) and an ink droplet is discharged from the nozzle  21 . 
     In this manner, according to the piezoelectric actuator  300  and the drive signal COM of the present embodiment, since the piezoelectric actuator  300  deforms to the opposite side from the pressure generating chamber  12  due to the expanding element P 1 , it is possible to set the internal stress of the piezoelectric actuator  300  to the contraction stress. Since the piezoelectric actuator  300  is only restored to the original shape by the contracting element P 3 , it is possible to suppress the internal stress of the piezoelectric actuator  300  from becoming a tensile stress. Incidentally, when the piezoelectric actuator  300  is caused to flex and deform inside the pressure generating chamber  12 , the inner portion of the piezoelectric actuator  300  is subjected to tensile stress. Since the piezoelectric layer  70  has a crystalline structure, the piezoelectric layer  70  is frailer to tensile stress than compressive stress. Therefore, by causing the piezoelectric actuator  300  to deform to the opposite side from the pressure generating chamber  12  and setting the internal stress to a compressive stress, it is possible to suppress destruction of the piezoelectric actuator  300  by internal stress. The potential difference which is applied by the expanding element P 1  is smaller than the potential difference which is applied by the contracting element P 3 , and since the contracting element P 3  only restores the piezoelectric actuator  300  to the original shape in which a voltage is not being applied, it is possible to reduce the internal stress from the expanding element P 1  to the contracting element P 3 . Therefore, it is possible to suppress the destruction of the piezoelectric actuator  300  by internal stress. 
     Second Embodiment 
       FIG. 13  is a sectional diagram of the main portions of the ink jet recording head which is an example of the liquid ejecting head according to the second embodiment of the invention. Members which are the same as those in the embodiment described above are assigned identical reference signs and numerals and a repeated description will be omitted. 
     As illustrated in  FIG. 13 , in the present embodiment, the diaphragm  50  of the non-drive portions  311  and  312  are thinner in the third direction Z than the other regions, that is, than the diaphragm  50  of the active portion  310 . In the present embodiment, in the non-drive portion  311 , the thickness of the diaphragm  50  which serves as the bottom surface of the recessed portion  71  of the piezoelectric layer  70  is thinner than the other regions. 
     For example, it is possible to form the diaphragm  50  by over etching when performing the patterning of the piezoelectric layer  70  using dry etching. 
     In this manner, by rendering the diaphragm  50  of the non-drive portion  311  thinner than the other regions, it is possible to suppress the hindrance of the deformation of the active portion  310  by the diaphragm  50  of the non-drive portion  311  and for displacement to occur more easily when driving the piezoelectric actuator  300 . 
     Third Embodiment 
       FIG. 14  is a sectional diagram of the main portions of the ink jet recording head which is an example of the liquid ejecting head according to the third embodiment of the invention. Members which are the same as those in the embodiment described above are assigned identical reference signs and numerals and a repeated description will be omitted. 
     As illustrated in  FIG. 14 , in the present embodiment, the piezoelectric layer  70  is formed at the non-drive portion  311 . In other words, the recessed portion  71  of the first and second embodiments which are described above is formed in the piezoelectric layer  70 . In this manner, by forming the piezoelectric layer  70  at the non-drive portion  311 , the rigidity of the non-drive portion  311  is increased, and it is possible to suppress the destruction of the non-drive portion  311 . 
     In the present embodiment, the piezoelectric layer  70  of the non-drive portion  311  is thinner than the active portion  310 . Even in the non-drive portion  312 , the piezoelectric layer  70  is formed thinly in the same manner as the non-drive portion  311 . It is possible to form the thin piezoelectric layer  70  of this thickness using half etching. Naturally, the piezoelectric layer  70  of the non-drive portions  311  and  312  may be formed at the same thickness as the active portion  310 . 
     Fourth Embodiment 
       FIG. 15  is a sectional diagram of the main portions of the ink jet recording head which is an example of the liquid ejecting head according to the fourth embodiment of the invention. Members which are the same as those in the embodiment described above are assigned identical reference signs and numerals and a repeated description will be omitted. 
     As illustrated in  FIG. 15 , in the present embodiment, a compliance substrate  40  is provided between the communicating plate  15  and the nozzle plate  20 . The compliance substrate  40  is a flexible material with low rigidity, for example, it is possible to use a polyphenylene sulfide (PPS) film or the like. Naturally, the compliance substrate  40  may be a metal, a resin, or the like, and the material is not particularly limited. 
     In the nozzle plate  20 , when viewed in plan view from the third direction Z, the recessed portion  22  which is open to the compliance substrate  40  side is provided at a position which overlaps the manifold  16 . The portion at which the recessed portion  22  is formed in the compliance substrate  40  serves as the compliance portion  23  which is capable of flexing and deforming. In the present embodiment, the recessed portion  22  is provided in the nozzle plate  20 ; however, the configuration is not particularly limited thereto, and a through hole which penetrates the nozzle plate  20  in the thickness direction may be provided at a position which overlaps the manifold  16 . However, since the compliance substrate  40  is exposed to the liquid ejecting surface in which the nozzles  21  are opened, it is preferable that the through hole of the nozzle plate  20  be covered by another member. 
     In this manner, even if the compliance portion  23  is formed by providing the compliance substrate  40 , it is possible to absorb the pressure fluctuations in the manifolds  16  using the compliance portion  23 . Other Embodiments 
     Each of the embodiments of the invention is described above; however, the basic configuration of the invention is not limited to the above-described configuration. 
     For example, in the embodiments which are described above, the active portion  310  which continues across the sides of the opening  12   a  of the parallelogram of the pressure generating chamber  12  is provided; however, the configuration is not particularly limited thereto, and the active portion  310  may be provided on at least the sides of the opening  12   a  of the parallelogram, and the active portion  310  may be noncontinuous along the sides. For example, when viewed in plan view from the third direction Z, the portions which overlap the corner portions of the opening  12   a  of the parallelogram may be set to non-drive portions and the active portion  310  may be provided to overlap sides other than at the corner portions. 
     In the embodiments which are described above, the first electrode  60  is set to the individual electrode by providing the first electrodes  60  independently for each of the plurality of active portions  310  and the second electrode  80  is set to the common electrode by providing the second electrode  80  continuously along the plurality of active portions  310 ; however, the configuration is not particularly limited thereto, and the first electrode  60  may be set to the common electrode by providing the first electrode  60  continuously along the plurality of active portions  310  and the second electrode  80  may be set to the individual electrode by providing the second electrodes  80  independently for each of the plurality of active portions  310 . Even if one of the first electrode  60  and the second electrode  80  is the individual electrode and the other is the common electrode, the active portion  310  may be defined by either of the first electrode  60  and the second electrode  80 . In other words, even if, as in the embodiments which are described above, the first electrode  60  is the individual electrode, the active portion  310  may be defined by the second electrode  80 , and the active portion  310  may be defined by both of the first electrode  60  and the second electrode  80 . Even if the second electrode  80  is the individual electrode, the active portion  310  may be defined by the first electrode  60 , and the active portion  310  may be defined by both of the first electrode  60  and the second electrode  80 . 
     In the embodiments which are described above, in the second direction Y four rows of the pressure generating chambers  12  are provided to line up in the first direction X; however, a group of two rows of the pressure generating chambers  12  which communicate with the single common manifold may be disposed at different positions in the first direction X. Accordingly, it is possible to dispose the nozzles  21  at twice the density in the first direction X. Therefore, high-density printing becomes possible. The number of rows of the pressure generating chambers  12  is not limited to that which is described above, and there may be one row or multiple rows of greater than or equal to two rows of the pressure generating chambers  12 . 
     In the embodiments which are described above, the compliance portion  23  is provided; however, the configuration is not particularly limited thereto. For example, in a case in which the volume of the manifold  16  is sufficiently secured with respect to the volume of the pressure generating chamber  12  and it is possible to absorb the pressure fluctuations inside the manifold  16  using the ink inside the manifold  16 , as illustrated in  FIG. 16 , the compliance portion  23  may not be provided.  FIG. 16  is a sectional diagram of the ink jet recording head according to the other embodiment of the invention. 
     In the embodiments which are described above, a silicon monocrystalline substrate having a surface with a crystalline plane azimuth of (100) is used as the flow path forming substrate  10 ; however, the configuration is not limited thereto, and a silicon monocrystalline substrate having a surface with a crystalline plane azimuth of (110) may be used, and a material such as an SOI substrate or glass may be used. The shape of the pressure generating chamber  12  is not limited to that which is described above and may be a shape in which the inclined surface  13  is not provided. The shapes of the openings  12   a  and  12   b  of the pressure generating chamber  12  are not limited to the parallelogram and may be shapes such as a polygon, a circle, and an ellipse. 
     In the ink jet recording apparatus I which is described above, a configuration is exemplified in which the recording head  1  is mounted on the carriage  3  and moves in the second direction Y; however, the configuration is not particularly limited thereto, and, for example, it is also possible to apply the invention to a so-called line recording apparatus in which the recording head  1  is fixed to the apparatus main body  4  and the printing is performed by only causing the recording sheet S such as the paper to move in the first direction X. 
     In the embodiments which are described above, the ink jet recording head is given as an example of the liquid ejecting head, and an ink jet recording apparatus is given as an example of the liquid ejecting apparatus; however, the invention is widely targeted at liquid ejecting heads and liquid ejecting apparatuses in general, and naturally, it is possible to apply the invention to a liquid ejecting head or a liquid ejecting apparatus which ejects a liquid other than the ink. Examples of other liquid ejecting heads include a variety of recording heads which are used in an image recording apparatus such as a printer, color material ejecting heads which are used in the manufacture of color filters of liquid crystal displays and the like, electrode material ejecting heads which are used to form electrodes of organic EL displays, field emission displays (FED), and the like, and biological organic matter ejecting heads which are used in the manufacture of biochips. It is possible to apply the other liquid ejecting heads to a liquid ejecting apparatus which is provided with the liquid ejecting head. 
     The invention is not limited to the liquid ejecting head and may also be used in another piezoelectric device having a substrate provided with a space and a piezoelectric actuator. Examples of other piezoelectric devices include, an ultrasonic device such as an ultrasonic transmitter, an ultrasonic motor, a thermoelectric converter, a pressure-electric converter, a ferroelectric transistor, a piezoelectric transformer, a filter such as a blocking filter of harmful light such as infrared rays, an optical filter using the photonic crystal effect by quantum dot formation, and an optical filter using thin film optical interference, various sensors such as an infrared sensor, an ultrasonic sensor, a thermal sensor, a pressure sensor, a pyroelectric sensor, and a gyroscope (an angular velocity sensor), and ferroelectric memory.