JP5962935B2 - Liquid ejecting head and liquid ejecting apparatus - Google Patents

Description

  The present invention relates to a liquid ejecting head and a liquid ejecting apparatus that eject liquid from nozzle openings, and more particularly to an ink jet recording head and an ink jet recording apparatus that eject ink as liquid.

  An ink jet recording head, which is a typical example of a liquid ejecting head that ejects liquid droplets, includes, for example, a flow path forming substrate in which a pressure generating chamber is formed, and a piezoelectric actuator provided on one side of the flow path forming substrate. In some cases, an ink droplet is ejected from a nozzle opening by applying a pressure in the pressure generating chamber by the displacement of the piezoelectric actuator.

  In such an ink jet recording head, the components contained in the ink evaporate from the nozzle openings, thereby increasing the viscosity of the ink, causing variations in the ejection characteristics of the ink droplets over time, and keeping the liquid ejection quality constant. I can't. In addition, the liquid ejection quality is also due to the difference between the ink droplet component when the component contained in the ink settles and ejected continuously and the component of the ink droplet when ejected for a long time. Variation will occur.

  For this reason, ink is supplied to a common liquid chamber in which a plurality of pressure generating chambers communicate in common, ink is recovered from the common liquid chamber, and the ink is circulated by repeating supply and recovery, thereby An ink jet recording head that suppresses thickening and sedimentation of components contained in ink has been proposed (see, for example, Patent Documents 1 and 2).

JP 2009-247938 A Japanese Patent No. 3161095

  However, as in Patent Documents 1 and 2, even if the ink in the common liquid chamber that communicates in common with the plurality of pressure generation chambers is circulated, the viscosity of the ink in the vicinity of the nozzle opening immediately before being ejected as an ink droplet is increased. Further, there is a problem that the sedimentation of the ink components cannot be suppressed, and the jetting quality of the liquid is deteriorated.

  Such a problem exists not only in an ink jet recording head that ejects ink but also in a liquid ejecting head that ejects liquid other than ink.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid ejecting head and a liquid ejecting apparatus that can reliably suppress liquid thickening and sedimentation of components to improve liquid ejecting quality.

An aspect of the present invention that solves the above problems includes a nozzle plate provided with a nozzle opening for ejecting liquid, a flow path forming substrate provided with a pressure generation chamber communicating with the nozzle opening, and a liquid in the pressure generation chamber. Pressure generating means for causing a pressure change in the gas, and a communication plate provided between the nozzle plate and the flow path forming substrate. The communication plate includes the pressure generation chamber, the nozzle opening, A communication path that communicates with the communication path and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and the nozzle plate is smaller than the communication plate. The communication plate is formed by laminating a first communication plate and a second communication plate, and the first communication plate has a concave shape opening to the second communication plate side, and the second communication plate Is in the liquid jet head covering the concave shape.
In this aspect, by providing the communication plate having the communication path and the circulation flow path, the liquid in the vicinity of the nozzle opening can be circulated by the flow path closer to the nozzle opening than the pressure generating chamber, and immediately before being discharged as a droplet. It is possible to reliably suppress the drying of the liquid and sedimentation of the contained components.
Moreover, the flow path of a nozzle plate or a flow path formation board | substrate can be simplified by providing the flow path of various functions, such as a communication path and a circulation flow path, in a communicating plate. Furthermore, by making the nozzle plate smaller than the communication plate, it is possible to increase the number of nozzle plates and flow path forming substrates, thereby reducing the cost.
According to another aspect of the present invention, a nozzle plate provided with a nozzle opening for ejecting liquid, a flow path forming substrate provided with a pressure generation chamber communicating with the nozzle opening, and a liquid in the pressure generation chamber are provided. Pressure generating means for generating a pressure change, and a communication plate provided between the nozzle plate and the flow path forming substrate, and the communication plate includes the pressure generating chamber and the nozzle opening. A communication passage that communicates, and a circulation passage that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and the nozzle plate is smaller than the communication plate, The circulation flow path along the juxtaposed direction of the pressure generation chambers is disposed at a position overlapping the pressure generation chamber and the common liquid chamber in the stacking direction of the flow path forming substrate and the communication plate. Located in the liquid jet head.
In this aspect, by providing the communication plate having the communication path and the circulation flow path, the liquid in the vicinity of the nozzle opening can be circulated by the flow path closer to the nozzle opening than the pressure generating chamber, and immediately before being discharged as a droplet. It is possible to reliably suppress the drying of the liquid and sedimentation of the contained components.
Moreover, the flow path of a nozzle plate or a flow path formation board | substrate can be simplified by providing the flow path of various functions, such as a communication path and a circulation flow path, in a communicating plate. Furthermore, by making the nozzle plate smaller than the communication plate, it is possible to increase the number of nozzle plates and flow path forming substrates, thereby reducing the cost.
Furthermore, the circulation channel is arranged at a position overlapping the pressure generation chamber and the common liquid chamber in the stacking direction of the channel formation substrate and the communication plate, thereby increasing the cross-sectional area of the circulation channel and circulating the circulation channel. The characteristics can be improved.
Here, the communication plate is formed by laminating a first communication plate and a second communication plate, the first communication plate has a concave shape that opens to the second communication plate side, and the second communication plate The communication plate preferably covers the concave shape.
The flow path forming substrate is provided with a plurality of rows in which the pressure generating chambers are arranged in parallel, and the circulation flow channel communicates with each row of the pressure generating chambers and is independent for each row. Are preferably provided. According to this, a different kind of liquid can be supplied and discharged for every row | line | column of each pressure generation chamber.
Furthermore, another aspect of the present invention provides a nozzle plate provided with a nozzle opening for ejecting liquid, a flow path forming substrate provided with a pressure generation chamber communicating with the nozzle opening, and a liquid in the pressure generation chamber. Pressure generating means for generating a pressure change, and a communication plate provided between the nozzle plate and the flow path forming substrate, and the communication plate includes the pressure generating chamber and the nozzle opening. A communication passage that communicates, and a circulation passage that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and the nozzle plate is smaller than the communication plate, The nozzle plate is in a liquid ejecting head that covers the circulation flow path and the communication path.
In this aspect, by providing the communication plate having the communication path and the circulation flow path, the liquid in the vicinity of the nozzle opening can be circulated by the flow path closer to the nozzle opening than the pressure generating chamber, and immediately before being discharged as a droplet. It is possible to reliably suppress the drying of the liquid and sedimentation of the contained components.
Moreover, the flow path of a nozzle plate or a flow path formation board | substrate can be simplified by providing the flow path of various functions, such as a communication path and a circulation flow path, in a communicating plate. Furthermore, by making the nozzle plate smaller than the communication plate, it is possible to increase the number of nozzle plates and flow path forming substrates, thereby reducing the cost.
According to another aspect of the present invention, a nozzle plate provided with a nozzle opening for ejecting liquid, a flow path forming substrate provided with a pressure generation chamber communicating with the nozzle opening, and a liquid in the pressure generation chamber are provided. Pressure generating means for generating a pressure change, and a communication plate provided between the nozzle plate and the flow path forming substrate, and the communication plate includes the pressure generating chamber and the nozzle opening. A communication passage that communicates, and a circulation passage that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and the nozzle plate is smaller than the communication plate, The flow path forming substrate is provided with at least two rows in which the pressure generation chambers are arranged in parallel, and the circulation flow path is provided as a common liquid chamber communicating with the two rows of the pressure generation chambers. To the liquid jet head That.
In this aspect, by providing the communication plate having the communication path and the circulation flow path, the liquid in the vicinity of the nozzle opening can be circulated by the flow path closer to the nozzle opening than the pressure generating chamber, and immediately before being discharged as a droplet. It is possible to reliably suppress the drying of the liquid and sedimentation of the contained components.
Moreover, the flow path of a nozzle plate or a flow path formation board | substrate can be simplified by providing the flow path of various functions, such as a communication path and a circulation flow path, in a communicating plate. Furthermore, by making the nozzle plate smaller than the communication plate, it is possible to increase the number of nozzle plates and flow path forming substrates, thereby reducing the cost.
Further, the liquid in the two rows of pressure generating chambers can be circulated through one circulation channel, and the structure can be simplified and the cost can be reduced.
Here, it is preferable that the nozzle plate covers the circulation flow path and the communication path.
Moreover, it is preferable that the flow path forming substrate is provided with an extended portion that communicates with the circulation flow path and expands a cross-sectional area of the circulation flow path. According to this, it is possible to improve the circulation characteristic by increasing the cross-sectional area of the circulation channel.
Further, it is preferable that the common liquid chamber is defined by the communication plate and is not defined by the nozzle plate.
According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect.
In this aspect, a liquid ejecting apparatus with improved liquid ejecting quality can be realized.
In another aspect , a pressure change is caused in the liquid in the pressure generating chamber, the nozzle plate provided with the nozzle opening for ejecting the liquid, the flow path forming substrate provided with the pressure generating chamber communicating with the nozzle opening. A pressure generating means; and a communication plate provided between the nozzle plate and the flow path forming substrate, and the communication plate includes a communication passage communicating the pressure generation chamber and the nozzle opening. A circulation channel that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and the nozzle plate is smaller than the communication plate. Located in the jet head.
In this aspect, by providing the communication plate having the communication path and the circulation flow path, the liquid in the vicinity of the nozzle opening can be circulated by the flow path closer to the nozzle opening than the pressure generating chamber, and immediately before being discharged as a droplet. It is possible to reliably suppress the drying of the liquid and sedimentation of the contained components.
Moreover, the flow path of a nozzle plate or a flow path formation board | substrate can be simplified by providing the flow path of various functions, such as a communication path and a circulation flow path, in a communicating plate. Furthermore, by making the nozzle plate smaller than the communication plate, it is possible to increase the number of nozzle plates and flow path forming substrates, thereby reducing the cost.
Here, it is preferable that the common liquid chamber is defined by the communication plate and not defined by the nozzle plate.
The communication plate is formed by laminating a first communication plate and a second communication plate, and the first communication plate has a concave shape opened to the second communication plate side, and the second communication plate The plate preferably covers the concave shape.
In addition, the circulation flow path along the direction in which the pressure generation chambers are arranged is disposed at a position overlapping the pressure generation chamber and the common liquid chamber in the stacking direction of the flow path forming substrate and the communication plate. It is preferable. According to this, it is possible to improve the circulation characteristic by increasing the cross-sectional area of the circulation channel.
The flow path forming substrate is provided with a plurality of rows in which the pressure generating chambers are arranged in parallel, and the circulation flow channel communicates with each row of the pressure generating chambers and is independent for each row. Are preferably provided. According to this, a different kind of liquid can be supplied and discharged for every row | line | column of each pressure generation chamber.
The nozzle plate preferably covers the circulation channel and the communication path.
Further, the flow path forming substrate is provided with at least two rows in which the pressure generation chambers are arranged in parallel, and the circulation flow path is a common liquid chamber communicating with the two rows of the pressure generation chambers. It is preferable that it is provided as. According to this, the liquid in the two rows of pressure generating chambers can be circulated through one circulation flow path, the structure can be simplified, and the cost can be reduced.
Moreover, it is preferable that the flow path forming substrate is provided with an extended portion that communicates with the circulation flow path and expands a cross-sectional area of the circulation flow path. According to this, it is possible to improve the circulation characteristic by increasing the cross-sectional area of the circulation channel.
According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect.
In this aspect, a liquid ejecting apparatus with improved liquid ejecting quality can be realized.
In another aspect, a pressure change is caused in the liquid in the pressure generating chamber, the nozzle plate provided with the nozzle opening for ejecting the liquid, the flow path forming substrate provided with the pressure generating chamber communicating with the nozzle opening. A pressure generating means; and a communication plate provided between the nozzle plate and the flow path forming substrate and provided with a communication path that communicates the pressure generation chamber and the nozzle opening. In the liquid ejecting head, the plate is provided with a circulation channel that communicates the communication path and a common liquid chamber that communicates in common with the plurality of pressure generation chambers.
In this aspect, by providing the communication plate having the communication path and the circulation flow path, the liquid in the vicinity of the nozzle opening can be circulated by the flow path closer to the nozzle opening than the pressure generating chamber, and immediately before being discharged as a droplet. It is possible to reliably suppress the drying of the liquid and sedimentation of the contained components. Moreover, the flow path of a nozzle plate or a flow path formation board | substrate can be simplified by providing the flow path of various functions, such as a communication path and a circulation flow path, in a communicating plate. Therefore, the area of the nozzle plate and the flow path forming substrate can be reduced, and the number of nozzle plates and flow path forming substrates can be increased to reduce the cost.

  Here, the flow path forming substrate is provided with at least two rows in which the pressure generation chambers are arranged in parallel, and the circulation flow path is a common liquid communicating with the two rows of the pressure generation chambers. It is preferable that it is provided as a chamber. According to this, the liquid in the two rows of pressure generating chambers can be circulated through one circulation flow path, the structure can be simplified, and the cost can be reduced.

  The flow path forming substrate is provided with a plurality of rows in which the pressure generating chambers are arranged in parallel, and the circulation flow channel communicates with each row of the pressure generating chambers and is independent for each row. Are preferably provided. According to this, a different kind of liquid can be supplied and discharged for every row | line | column of each pressure generation chamber.

  Moreover, it is preferable that the flow path forming substrate is provided with an extended portion that communicates with the circulation flow path and expands a cross-sectional area of the circulation flow path. According to this, it is possible to improve the circulation characteristic by increasing the cross-sectional area of the circulation channel.

  Further, it is preferable that the circulation flow path is disposed at a position overlapping the pressure generation chamber in the stacking direction of the flow path forming substrate and the communication plate. According to this, it is possible to improve the circulation characteristic by increasing the cross-sectional area of the circulation channel.

  In addition, the circulation channel is provided to be inclined with respect to the flow direction in which the liquid flows from the pressure generation chamber toward the common liquid chamber, and the cross-sectional area of the circulation channel is gradually reduced toward the downstream side. And a second wall surface that is inclined with respect to the flow direction and that gradually increases the cross-sectional area that is gradually reduced by the first wall surface. The inclination angle of one wall surface with respect to the inner surface upstream of the first wall surface of the circulation channel is larger than the inclination angle of the second wall surface with respect to the inner surface downstream of the second wall surface of the circulation channel. Is preferred. According to this, by providing the throttle part, it is possible to cause a difference in the channel resistance between the forward direction from the pressure generation chamber of the liquid passing through the circulation channel toward the manifold and the opposite direction which is the opposite direction. it can. For this reason, the liquid can be circulated only by the pressure fluctuation to the liquid in the pressure generating chamber by the pressure generating means, and a separate pump or the like is not required, and the cost can be reduced.

  Moreover, it is preferable that a plurality of the throttle portions are provided. According to this, the difference (ratio) of the flow path resistance between the forward direction and the reverse direction can be increased.

  The first wall surface may be formed of a curved surface.

According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect.
In this aspect, a liquid ejecting apparatus with improved liquid ejecting quality can be realized.

FIG. 3 is an exploded perspective view of the recording head according to the first embodiment. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment. FIG. 3 is a cross-sectional view illustrating a flow path of the recording head according to the first embodiment. 6 is a cross-sectional view of a recording head according to Embodiment 2. FIG. FIG. 6 is a cross-sectional view illustrating a flow path of a recording head according to a third embodiment. FIG. 10 is an enlarged perspective view illustrating a main part showing a flow path of a recording head according to a third embodiment. FIG. 10 is an enlarged plan view showing a main part showing a flow channel according to Embodiment 3. FIG. 10 is a cross-sectional view showing a modification of the flow channel according to the third embodiment. It is the top view to which the principal part which shows the modification of the flow path which concerns on Embodiment 3 was expanded. It is the top view to which the principal part which shows the modification of the flow path which concerns on Embodiment 3 was expanded. 1 is a diagram illustrating a schematic configuration of a recording apparatus according to an embodiment.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is an exploded perspective view of an ink jet recording head showing an example of a liquid jet head according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view in a short direction of a pressure generating chamber of the ink jet recording head. FIG. 3 is a cross-sectional view taken along the line AA ′ in FIG. 2 and an enlarged cross-sectional view thereof, and FIG. 4 is a cross-sectional view showing a flow path configuration.

  As shown in the figure, the flow path forming substrate 10 is made of a silicon single crystal substrate having a plane orientation (110) in this embodiment, and an elastic film 50 made of silicon dioxide is formed on one surface thereof. The flow path forming substrate 10 is formed with two rows in which a plurality of pressure generating chambers 12 are arranged in a substantially straight line. In the two rows in which the pressure generation chambers 12 are arranged in a substantially straight line, the row of the pressure generation chambers 12 is arranged in the direction of arrangement of the other pressure generation chambers 12 with respect to the row of one pressure generation chamber 12. It is arranged at a position shifted by half of the adjacent interval. As a result, the nozzle openings 21 to be described in detail later are similarly arranged so that two rows of the nozzle openings 21 are shifted by a half interval to double the resolution.

  In addition, an ink supply path 14 is provided on one end side in the longitudinal direction of the pressure generation chamber 12 of the flow path forming substrate 10, and ink from a manifold that is a common liquid chamber common to the plurality of pressure generation chambers 12. Is supplied to the pressure generating chamber 12 through the ink supply path 14. The ink supply path 14 is formed with a narrower width than the pressure generation chamber 12, and maintains a constant flow path resistance of ink flowing from the manifold 100 into the pressure generation chamber 12. Incidentally, in this embodiment, the pressure generating chamber 12 and the ink supply path 14 constitute a plurality of individual flow paths communicating with the manifold which is a common flow path.

  Further, a communication plate 15 is provided on the opening surface side (the side opposite to the elastic film 50) of the flow path forming substrate 10 via an adhesive, a heat welding film, or the like. The communication plate 15 is provided with a communication passage 16 penetrating in the thickness direction communicating with each pressure generating chamber 12. The communication passage 16 is provided in communication with an end portion on the opposite side of the end portion communicating with the ink supply path 14 in the longitudinal direction of the pressure generation chamber 12. The communication path 16 is provided independently for each pressure generating chamber 12. Therefore, the communication path 16 is also arranged on a substantially straight line in the same manner as the row formed by the pressure generation chambers 12. The pressure generation chamber 12 communicates with a nozzle opening 21 described later in detail through such a communication passage 16.

  The communication plate 15 is provided with a circulation channel 17. The circulation channel 17 is provided between the row of the pressure generation chambers 12 arranged in parallel and another row of the pressure generation chambers 12 adjacent to the row and arranged in a substantially straight line. A plurality of pressure generating chambers 12 are provided along the juxtaposed direction. The circulation passage 17 is provided with each communication passage 16 of the communication plate 15 for each communication passage 16 and communicates with each other via a circulation communication passage 16a having a concave shape opened to the nozzle plate 20 side. Has been. Further, in the present embodiment, each of the rows formed by the pressure generation chambers 12 arranged in parallel is connected to the circulation flow path 17 via each communication path 16 in common.

  Such a circulation channel 17 is provided through the communication plate 15 in the thickness direction. Moreover, in this embodiment, the extended part 18 which has a concave shape is provided so that a part of circulation flow path 17 of the flow path formation board | substrate 10 may be faced. The expansion portion 18 has a concave shape that has substantially the same opening width as the circulation flow path 17 and substantially the same opening length as the circulation flow path 17, and has a cross-sectional area (flow path diameter) of the circulation flow path 17. (Direction cross-sectional area) is widened. That is, actually, the circulation flow path 17 provided in the communication plate 15 and the extended portion 18 provided in the flow path forming substrate 10 constitute the circulation flow path of the present embodiment.

  In addition, the surface (surface on the nozzle plate 20 side) opposite to the side where the expansion portion 18 of the circulation channel 17 is provided is sealed by the nozzle plate 20.

  Such a communication plate 15 has a larger area than the flow path forming substrate 10 (bonding surface with the flow path forming substrate 10), and a case described later in detail outside the ink supply path 14 of the flow path forming substrate 10. A manifold 100 is defined with the member 40. For this reason, the communication plate 15 has substantially the same area as the case member 40 in a plan view from the droplet discharge direction.

  A nozzle plate 20 is provided on the side of the communication plate 15 opposite to the flow path forming substrate 10 via an adhesive, a heat welding film, or the like. The nozzle plate 20 is provided with nozzle openings 21 that communicate with the pressure generation chambers 12 through the communication passages 16. The nozzle plate 20 is made of a metal such as stainless steel, glass ceramics, a silicon single crystal substrate, or the like.

  Such a nozzle plate 20 is smaller than the communication plate 15 in this embodiment. The nozzle plate 20 has a size that covers in common the openings on the nozzle plate 20 side of at least two rows of communication paths 16. The nozzle plate 20 has a size that seals the circulation channel 17. That is, the nozzle plate 20 is provided in such a size as to cover the circulation flow path 17 and the communication path 16 provided in the communication plate 15 without covering one side of the communication plate 15. Thus, the cost can be reduced by making the area in plan view from the discharge direction of the nozzle plate 20 smaller than the area in plan view from the discharge direction of the communication plate 15. Incidentally, although not shown, a water repellent film having water repellency (liquid repellency) is provided on the liquid ejecting surface of the nozzle plate 20 (the surface opposite to the communication plate 15). Such a water-repellent film is expensive, and the cost of the nozzle plate 20 increases depending on the area where the water-repellent film is formed. In the present embodiment, by reducing the area of the nozzle plate 20, the area for forming the water repellent film can be reduced and the cost of the nozzle plate 20 can be reduced. Of course, the cost can be reduced by simply reducing the area of the metal plate or ceramic plate that is the material of the nozzle plate 20.

  On the other hand, the elastic film 50 is formed on the side opposite to the opening surface of the flow path forming substrate 10 as described above, and an insulator film 55 made of, for example, zirconium oxide is formed on the elastic film 50. Is formed. Further, on the insulator film 55, the first electrode 60, the piezoelectric layer 70, and the second electrode 80 are sequentially stacked by film formation and lithography to constitute the piezoelectric actuator 300. Here, the piezoelectric actuator 300 refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. In general, one electrode of the piezoelectric actuator 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In the present embodiment, the first electrode 60 is a common electrode of the piezoelectric actuator 300, and the second electrode 80 is an individual electrode of the piezoelectric actuator 300. However, there is no problem even if this is reversed for the convenience of the drive circuit and wiring. In the above-described example, the elastic film 50, the insulator film 55, and the first electrode 60 function as a diaphragm. However, the present invention is not limited to this. For example, the elastic film 50 and the insulator film 55 are provided. Instead, only the first electrode 60 may act as a diaphragm. Further, the piezoelectric actuator 300 itself may substantially serve as a diaphragm.

  In addition, a lead electrode 90 made of, for example, gold (Au) or the like is connected to the second electrode 80 that is an individual electrode of each piezoelectric actuator 300. The lead electrode 90 is connected to a wiring board 121 such as a COF which is a flexible wiring provided with a driving circuit 120 such as a driving IC. A signal from the driving circuit 120 passes through the wiring board 121 and the lead electrode 90. And supplied to each piezoelectric actuator 300.

  Further, a protective substrate 30 having a holding portion 31 capable of securing a space that does not hinder its movement in a region facing the piezoelectric actuator 300 is provided on the surface of the flow path forming substrate 10 on the side of the piezoelectric actuator 300. It is joined via a heat welding film or the like. Since the piezoelectric actuator 300 is formed in the holding portion 31, it is protected in a state where it is hardly affected by the external environment. In the present embodiment, two rows in which the piezoelectric actuators 300 are juxtaposed in the width direction are provided corresponding to two rows in which the pressure generating chambers 12 are juxtaposed in the width direction. In addition to being provided in common across the 300 rows arranged in the width direction, the holding portion 31 was provided independently for each row of the piezoelectric actuators 300.

  The protective substrate 30 is provided with a through hole 32 provided between the two holding portions 31 so as to penetrate the protective substrate 30 in the thickness direction. The end portion of the lead electrode 90 drawn out from the piezoelectric actuator 300 of the flow path forming substrate 10 is extended so as to be exposed in the through hole 32, and the lead electrode 90 and the wiring substrate 121 are in the through hole 32. Electrically connected.

  In this embodiment, such a protective substrate 30 is formed with substantially the same size (area on the bonding surface side) as the flow path forming substrate 10. Examples of the material of the protective substrate 30 include glass, ceramic material, metal, resin, and the like, but it is more preferable that the protective substrate 30 is formed of substantially the same material as the thermal expansion coefficient of the flow path forming substrate 10. In this embodiment, the silicon single crystal substrate made of the same material as the flow path forming substrate 10 is used.

  A case member 40 constituting the manifold 100 is joined to the surface of the protective substrate 30 opposite to the flow path forming substrate 10.

  The case member 40 has a recess 41 that holds the flow path forming substrate 10 and the protective substrate 30 inside on the protective substrate 30 side. The recess 41 has a larger area than the surface of the protective substrate 30 bonded to the flow path forming substrate 10, and has substantially the same depth as the combined thickness of the flow path forming substrate 10 and the protective substrate 30. . Then, the protective substrate 30 and the flow path forming substrate 10 are held in the recess 41 by sealing the opening surface of the recess 41 with the communication plate 15. That is, the surface of the protective substrate 30 opposite to the flow path forming substrate 10 is joined to the inner surface of the recess 41, and the communication plate is connected to the surface (surface around the recess 41) where the recess 41 of the case member 40 opens. 15 surfaces on the flow path forming substrate 10 side are joined. Accordingly, the flow path forming substrate 10 and the protective substrate 30 are held in the recess 41, and the case member 40 and the communication plate are disposed outside (end surface) of the flow path forming substrate 10 and the protective substrate 30 on the ink supply path 14 side. 15, a manifold 100 is formed. In the present embodiment, the protective substrate 30 and the flow path forming substrate 10 are held in the central portion of the concave portion 41 of the case member 40, and the manifold communicates in common with each pressure generating chamber 12 on both sides of the central portion of the concave portion 41. 100 was formed. As shown in FIG. 4, the manifold 100 has a flow path branched so that the ink flowing from the introduction path 42 provided in the case member 40 is distributed to each row of the pressure generation chambers 12. Yes. The case member 40 includes an introduction path 42 that communicates with the manifold 100 and supplies ink to the manifold 100, and a discharge path 43 that communicates with the circulation path 17 and discharges ink from the circulation path 17. , Is provided.

  The introduction path 42 communicates with the central portion of the upper portion of the manifold 100 (on the side opposite to the communication plate 15) provided on one side in the short direction of the pressure generation chamber 12 of the flow path forming substrate 10 and the protection substrate 30. Are arranged to be.

  The discharge path 43 is disposed on the side opposite to the introduction path 42 in the direction in which the pressure generation chambers 12 are arranged. In addition, a communication discharge path 44 that connects the discharge path 43 of the case member 40 and the circulation flow path 17 is provided in the flow path forming substrate 10, the protective substrate 30, and a sealing film 45 described later.

  As shown in FIG. 4, the supply path 8 and the recovery pipe 9 that are tubular members such as tubes connected to the liquid storage means 5 in which external ink is stored are provided in the introduction path 42 and the discharge path 43. Connected. Specifically, the supply pipe 8 has one end connected to the liquid storage unit 5 and the other end connected to the introduction path 42, and supplies the ink of the liquid storage unit 5 to the case member 40.

  The recovery pipe 9 has one end connected to the liquid storage means 5 and the other end connected to the discharge path 43. A pump 9a is provided in the middle of the recovery pipe 9, and the ink from the liquid storage means 5 is returned from the ink jet recording head 1 to the liquid storage means 5 by the pressure of the pump 9a.

  A sealing film 45 is provided on the bottom surface of the recess 41 of the case member 40 to which the protective substrate 30 is bonded. The sealing film 45 is made of a material having low rigidity and flexibility, such as polyphenylene sulfide (PPS). A part of the manifold 100 is sealed by the sealing film 45.

  Moreover, since the area | region which opposes the manifold 100 of the case member 40 is the space part 46 which has a concave shape, a part by the case member 40 side (opposite side to the communicating plate 15) of the manifold 100 is sealed. It is a flexible part 47 which is sealed only by the stop film 45 and can be deformed.

  Further, the case member 40 is provided with a connection port 48 that penetrates in the thickness direction and communicates with the through hole 32 of the protective substrate 30. The wiring board 121 inserted through the connection port 48 is inserted through the through hole 32 of the protective substrate 30 and connected to the lead electrode 90. A wall 49 is provided at the opening edge of the connection port 48 on the opposite side of the surface of the case member 40 from which the recess 41 is opened. The wall portion 49 holds the wiring board 121 and the connection board 122 connected to the wiring board 121. In the present embodiment, the connection substrate 122 is a rigid substrate provided with a connector 123 to which external wiring is connected, and the wiring substrate 121 connected to the lead electrode 90 is electrically connected. Then, an external wiring (not shown) is connected to the connector 123 of the connection board 122, thereby supplying a print signal from the external wiring to the wiring board 121.

  By forming the manifold 100 using such a case member 40, the flow path forming substrate 10 and the protective substrate 30 can be reduced in size. Here, for example, when the manifold is provided on the flow path forming substrate or the protective substrate, the flow path forming substrate and the protective substrate define the peripheral wall of the manifold, and the flow path forming substrate and the protective substrate are arranged in the longitudinal direction of the pressure generating chamber. It gets bigger in the direction. On the other hand, in the present embodiment, the end surfaces of the flow path forming substrate 10 and the protective substrate 30 define one surface of the manifold 100 (longitudinal direction of the pressure generating chamber 12), and the other surface of the manifold 100 is the case member. Since 40 is defined, the flow path forming substrate 10 and the protective substrate 30 can be reduced in size. Thus, when the plurality of flow path forming substrates 10 and the protective substrate 30 are integrally formed on a large substrate such as a silicon wafer, the flow path forming substrate 10 and the protective substrate 30 are reduced in size. The number of steps from the substrate can be increased, and the cost can be reduced. By integrally forming a plurality of flow path forming substrates 10 and protective substrates 30 on a large substrate such as a silicon wafer, it becomes possible to form a plurality of flow path forming substrates 10 and protective substrates 30 simultaneously. Cost can be reduced.

  Further, in the present embodiment, since the surface of the manifold 100 on the nozzle plate 20 side is defined by the communication plate 15, it is not necessary for the nozzle plate 20 to overlap the manifold 100 in the stacking direction (thickness direction). . Thereby, the area of the nozzle plate 20 can be narrowed, and the cost of the nozzle plate 20 can be reduced.

  In such an ink jet recording head 1, the ink from the liquid storage unit 5 is supplied to the introduction path 42 via the supply pipe 8. The ink supplied to the introduction path 42 is supplied from the manifold 100 to each pressure generating chamber 12. Then, in accordance with a signal from the drive circuit 120, the piezoelectric actuator 300 corresponding to the pressure generation chamber 12 is driven to bend and deform, thereby changing the volume of the pressure generation chamber 12 and ejecting ink droplets from the nozzle openings 21. The

  The ink supplied to the pressure generating chamber 12 is discharged to the recovery pipe 9 via the communication path 16, the circulation path 17 and the discharge path 43 by the pressure of the pump 9 a, and the liquid storage means 5 via the recovery pipe 9. To be recovered. At this time, the communication path 16 that connects the pressure generation chamber 12 and the nozzle opening 21 is provided, and the communication path 16 is connected to the circulation flow path 17 so that the ink immediately before ejection near the nozzle opening 21 is supplied to the liquid storage unit 5. The so-called circulation can be performed. Therefore, it is possible to suppress the increase in viscosity due to drying of the ink immediately before ejection and the sedimentation of the components contained in the ink, so that the ink ejection characteristics can be made substantially constant even after a certain time has elapsed. As a result, it is possible to improve the ejection quality of the liquid while suppressing variations in ejection characteristics.

(Embodiment 2)
FIG. 5 is a cross-sectional view of an ink jet recording head which is an example of a liquid jet head according to Embodiment 2 of the present invention. In addition, the same code | symbol is attached | subjected to the member similar to embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 5, the ink jet recording head 1 </ b> A of the present embodiment includes a flow path forming substrate 10 provided with a piezoelectric actuator 300 and the like, a nozzle plate 20 provided with a nozzle opening 21, and a flow path forming substrate 10. And a communication plate 15 </ b> A provided between the nozzle plate 20, a protective substrate 30, and a case member 40.

  The communication plate 15A is provided between the flow path forming substrate 10 and the nozzle plate 20, and is provided on the first communication plate 151 provided on the flow path forming substrate 10 side and the nozzle plate 20 side. The second communication plate 152 is laminated.

  The communication plate 15A is provided with a communication path 16A, a circulation flow path 17A, and a circulation communication path 16a that communicates the communication path 16A and the circulation flow path 17A.

  The communication path 16 </ b> A communicates the pressure generation chamber 12 and the nozzle opening 21 at the end of the pressure generation chamber 12 opposite to the ink supply path 14.

  The circulation channel 17A has a concave shape that opens to the second communication plate 152 side of the first communication plate 151, and the opening of the circulation channel 17A on the nozzle plate 20 side is sealed by the second communication plate 152. Yes. Such a circulation flow path 17A includes a row of pressure generation chambers 12 arranged in parallel in the width direction in the stacking direction of the communication plate 15A and the flow path forming substrate 10, and a manifold common to one row of the pressure generation chambers 12. 100 and the position overlapping with 100. Further, the circulation channel 17A is provided for each row arranged in parallel in the width direction of the pressure generating chamber 12.

  The circulation flow path 17A and the communication path 16A have a concave shape opened on the surface of the first communication plate 151 on the second communication plate 152 side, and the circulation communication path 16a provided for each communication path 16A. It is communicated through.

  In the ink jet recording head 1A having such a circulation channel 17A, since the circulation channel 17A is provided for each row of the pressure generation chambers 12, the types of ink supplied to the two manifolds 100 may be different. it can. That is, different ink can be ejected from the two rows of nozzle openings 21.

(Embodiment 3)
FIG. 6 is a cross-sectional view showing a flow path configuration according to Embodiment 3 of the present invention, FIG. 7 is an enlarged perspective view of a main part of the circulation flow path, and FIG. 8 is a main part of the circulation flow path. FIG. In addition, the same code | symbol is attached | subjected to the member similar to embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in the drawing, the ink jet recording head 1B of the present embodiment has the same configuration as that of the first embodiment described above except that the throttle portion 200 is provided in the middle of the circulation flow path 17A.

  Specifically, a plurality of throttle portions 200 are provided on the downstream side (on the discharge passage 43 side) from the region connected to each circulation communication passage 16a of the circulation passage 17A, and two in the present embodiment.

  The throttle unit 200 is provided so as to protrude from the inner surface of the circulation channel 17A in the radial direction of the channel. That is, the throttle unit 200 protrudes in a direction intersecting the circulation flow path 17A with the flow of ink (hereinafter referred to as the forward direction d) flowing from the pressure generation chamber 12 side toward the manifold 100 (discharge path 43) side. The cross-sectional area in the flow path radial direction of the circulation flow path 17A is narrowed down. Hereinafter, the cross-sectional area of the circulation flow path 17A is a cross-sectional area in the flow path radial direction, and is a cross-sectional area that crosses the forward direction d.

  Further, the throttle unit 200 is provided to be inclined with respect to the forward direction d, and the first wall surface 201 that gradually decreases the cross-sectional area of the circulation channel 17A toward the downstream side (the discharge channel 43 side), and the forward direction d. A second wall surface 202 that is inclined with respect to the first wall surface 201 and gradually returns to the same cross-sectional area as the upstream side of the first wall surface 201. It has.

  That is, the narrowed portion 200 has a first wall surface 201 facing the upstream side in the forward direction d and a second wall surface 202 facing the downstream side.

  Further, in the throttle unit 200, the first wall surface 201 and the second wall surface 202 are formed as flat surfaces, and a shape that is continuous at the front end surface thereof, that is, the throttle unit 200 is viewed from the flow path forming substrate 10 side. It has a triangular shape.

Then, the first wall surface 201 of the throttle unit 200 has an inclination angle θ ₁ with respect to the inner surface of the circulation channel 17A upstream in the forward direction d with respect to the first wall surface 201 from the second wall surface 202 of the second wall surface 202. Is also larger than the inclination angle θ _{2 with} respect to the inner surface of the downstream circulation channel 17A in the forward direction d (θ ₁ > θ ₂ ).

  In other words, the first wall surface 201 of the throttle unit 200 has a ratio (decrease rate: inclination) of decreasing the cross-sectional area of the circulation channel 17A per unit distance in the forward direction d opposite to the forward direction d of the second wall surface 202. It is smaller than the rate (decrease rate: inclination) of decreasing the cross-sectional area of the circulation channel 17A per unit distance in the opposite direction.

  When the throttle unit 200 having the first wall surface 201 and the second wall surface 202 is provided as described above, the flow path resistance in the forward direction d of the ink flowing through the circulation flow path 17A can be made smaller than the flow path resistance in the reverse direction. it can. Specifically, when the width of the circulation channel 17A (the width in the longitudinal direction of the pressure generating chamber 12) throttled by the throttle unit 200 is 5.0 μm, the channel resistance in the forward direction d and the channel resistance in the reverse direction Is 0.84%. Further, when the width of the circulation channel 17A is set to 10 μm by the throttle unit 200, the ratio of the channel resistance becomes 0.65%.

  Therefore, in such an ink jet recording head 1 </ b> B, when the volume of the pressure generation chamber 12 is enlarged or reduced by driving the piezoelectric actuator 300 to generate positive pressure and negative pressure in the ink in the pressure generation chamber 12, the circulation is performed. The ink reciprocates in the forward direction d and the reverse direction in the flow path 17A. At this time, since the flow path resistance of the ink flowing in the circulation flow path 17A is different between the forward direction d and the reverse direction by providing the throttle part 200, the ink easily flows in the forward direction d, and in the reverse direction. Makes it difficult for ink to flow. Thereby, the ink in the pressure generating chamber 12 can be sent in the forward direction d through the circulation flow path 17 </ b> A by driving the piezoelectric actuator 300.

  Further, as in the first or second embodiment described above, the ink can be circulated only by driving the piezoelectric actuator 300 without providing the pump 9a. For this reason, the circulation channel 17A may be directly connected to the manifold 100. Such an example is shown in FIG. In the ink jet recording head shown in FIG. 9, the discharge path 43 and the communication discharge path 44 are not provided, and the manifold 100 </ b> A is provided over the outer periphery of the flow path forming substrate 10 and the protection substrate 30. One end (second wall surface 202 side) of the circulation channel 17A is connected to the manifold 100A. Even with such a configuration, the ink can be circulated only by driving the piezoelectric actuator 300 without providing the pump 9a and the like.

  In the above-described example, the two throttle portions 200 are provided on the opposing wall surfaces of the circulation channel 17A, respectively, but the present invention is not particularly limited thereto. For example, as shown in FIG. 10, the two throttle portions 200 may be provided so as to protrude in the same direction from the same wall surface of the circulation channel 17A. Further, the first wall surface 201 and the second wall surface 202 of the throttle unit 200 are not limited to flat surfaces because the cross-sectional area of the circulation channel 17A may be gradually reduced or gradually increased in the forward direction d. That is, for example, as shown in FIG. 11, the first wall surface 201 </ b> A having a curved surface (a cross section of an arc) may be provided in the diaphragm 200 </ b> A instead of a flat surface.

  Of course, the number and arrangement of the apertures 200 and 200A are not limited to those described above. For example, one or more apertures 200 and 200A may be provided, and the apertures 200 and 200A may be provided. You may make it provide in the circulation communication path 16a.

(Other embodiments)
As mentioned above, although each embodiment of this invention was described, the basic composition of this invention is not limited to what was mentioned above. For example, in each of the above-described embodiments, a silicon single crystal substrate is illustrated as the flow path forming substrate 10, but the present invention is not particularly limited thereto. For example, a material such as an SOI substrate, glass, metal, or the like may be used. .

  Further, in each of the embodiments described above, the thin film piezoelectric actuator 300 has been described as the pressure generating means for causing a pressure change in the pressure generating chamber 12, but the present invention is not particularly limited thereto. For example, a green sheet is attached. It is possible to use a thick film type piezoelectric actuator formed by such a method, a longitudinal vibration type piezoelectric actuator in which piezoelectric materials and electrode forming materials are alternately stacked and expanded and contracted in the axial direction. Also, as a pressure generating means, a heating element is arranged in the pressure generating chamber, and droplets are discharged from the nozzle opening by bubbles generated by the heat generated by the heating element, or static electricity is generated between the diaphragm and the electrode. Thus, a so-called electrostatic actuator that discharges liquid droplets from the nozzle openings by deforming the diaphragm by electrostatic force can be used.

  The ink jet recording head 1 described above constitutes a part of the ink jet recording head unit and is mounted on the ink jet recording apparatus. FIG. 12 is a schematic view showing an example of the ink jet recording apparatus.

  The ink jet recording apparatus of the present embodiment fixes the ink jet recording head 1 to the apparatus main body, and transports a medium to be ejected such as recording paper in a direction orthogonal to the direction in which the nozzle openings 21 are arranged in parallel. This is a so-called line-type ink jet recording apparatus that performs printing on a medium.

  Specifically, as shown in FIG. 12, an ink jet recording apparatus I supplies an ink jet recording head unit 2 having an ink jet recording head 1, an apparatus main body 3, and a recording sheet S as a recording medium. A paper roller 4 and liquid storage means 5 are provided.

  The ink jet recording head unit 2 (hereinafter also referred to as the head unit 2) includes a plurality of ink jet recording heads 1 and a plate-like base plate 6 that holds the plurality of ink jet recording heads 1. The head unit 2 is fixed to the apparatus main body 3 via a frame member 7 attached to the base plate 6.

  The apparatus body 3 is provided with a roller 4. The roller 4 conveys a recording sheet S such as paper that is an ejection medium fed to the apparatus main body 3 and passes the recording sheet S through the ink ejection surface side of the ink jet recording head 1.

  Further, as described above, each ink jet recording head 1 is connected to the liquid storage means 5 that is fixed to the apparatus main body 3 and stores ink via a supply pipe 8 such as a flexible tube and a recovery pipe 9. . Ink from the liquid storage means 5 is supplied to each ink jet recording head 1 via the supply pipe 8, and ink that has not been ejected by the ink jet recording head 1 is recovered to the liquid storage means 5 via the recovery pipe 9. The A pump 9a is provided in the middle of the recovery pipe 9, and ink from the liquid storage means 5 is supplied to the liquid flow path (manifold 100, circulation flow path 17 and the like) in the ink jet recording head 1 by the pressure of the pump 9a. ) To circulate.

  In such an ink jet recording apparatus I, the recording sheet S is transported in the transport direction by the roller 4, and ink is ejected by the ink jet recording head 1 of the head unit 2 to print an image or the like on the recording sheet S. .

  In the above example, only one head unit 2 including a plurality of ink jet recording heads 1 is provided in the ink jet recording apparatus I. However, two head units 2 mounted on the ink jet recording apparatus I are provided. You may provide above. Further, the ink jet recording head 1 may be directly mounted on the ink jet recording apparatus I.

  In the above-described example, the so-called line-type ink jet recording apparatus I that performs printing only by transporting the recording sheet S while the ink jet recording head 1 is fixed is illustrated, but the present invention is not particularly limited thereto. Absent. For example, an ink jet recording head 1 is mounted on a carriage that moves in a direction (main scanning direction) that intersects the conveyance direction of the recording sheet S, and printing is performed while moving the ink jet recording head 1 in the main scanning direction. The present invention can also be applied to a type of ink jet recording apparatus.

  Further, in the present embodiment, the ink jet type recording apparatus I in which the liquid storing means 5 is fixed to the apparatus main body 3 is illustrated, but the present invention is not particularly limited thereto. For example, the liquid storing means such as an ink cartridge is used for each ink jet. The present invention can also be applied to an ink jet recording apparatus of a type that is fixed to the ink jet recording head 1, the ink jet recording head unit 2, or a carriage.

  Furthermore, in this embodiment, the ink jet recording apparatus has been described as an example of the liquid ejecting apparatus. However, the present invention is intended for all liquid ejecting apparatuses having a liquid ejecting head widely, and liquid other than ink is used. Of course, the present invention can also be applied to a liquid ejecting apparatus including a liquid ejecting head for ejecting. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (field emission displays). Examples thereof include an electrode material ejection head used for electrode formation, a bioorganic matter ejection head used for biochip production, and the like.

  I ink jet recording apparatus (liquid ejecting apparatus), 1, 1A, 1B ink jet recording head (liquid ejecting head), 2 ink jet recording head unit (liquid ejecting head unit), 10 flow path forming substrate, 12 pressure generating chamber, 14 Ink supply path, 15, 15A communication plate, 16, 16A communication path, 17, 17A Circulation flow path, 18 Expansion section, 20 Nozzle plate, 21 Nozzle opening, 30 Protection substrate, 31 Holding section, 40 Case member, 41 Concavity , 50 elastic film, 55 insulator film, 60 first electrode, 70 piezoelectric layer, 80 second electrode, 90 lead electrode, 100, 100A manifold (common liquid chamber), 120 drive circuit, 121 wiring board, 122 connection board , 123 connector, 300 piezoelectric actuator Eta (pressure generating means)

Claims (10)

A nozzle plate provided with nozzle openings for ejecting liquid;
A flow path forming substrate provided with a pressure generating chamber communicating with the nozzle opening;
Pressure generating means for causing a pressure change in the liquid in the pressure generating chamber;
A communication plate provided between the nozzle plate and the flow path forming substrate,
In the communication plate,
A communication path communicating the pressure generation chamber and the nozzle opening;
A circulation channel that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and
The nozzle plate is rather smaller than the communicating plate,
The communication plate is formed by laminating a first communication plate and a second communication plate,
The first communication plate has a concave shape that opens to the second communication plate side,
The second communication plate is a liquid jet head that covers the concave shape. A nozzle plate provided with nozzle openings for ejecting liquid;
A flow path forming substrate provided with a pressure generating chamber communicating with the nozzle opening;
Pressure generating means for causing a pressure change in the liquid in the pressure generating chamber;
A communication plate provided between the nozzle plate and the flow path forming substrate,
In the communication plate,
A communication path communicating the pressure generation chamber and the nozzle opening;
A circulation channel that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and
The nozzle plate is rather smaller than the communicating plate,
The circulation flow path along the juxtaposed direction of the pressure generation chambers is disposed at a position overlapping the pressure generation chamber and the common liquid chamber in the stacking direction of the flow path forming substrate and the communication plate. Liquid jet head. The communication plate is formed by laminating a first communication plate and a second communication plate,
The first communication plate has a concave shape that opens to the second communication plate side,
It said second communicating plate, liquid-jet head according to claim 2, wherein the covering the concave shape. The flow path forming substrate is provided with a plurality of rows in which the pressure generation chambers are arranged in parallel, and the circulation flow channel communicates with each row of the pressure generation chambers and is independent for each row. liquid jet head according to any one of claim 1 to 3, characterized in that are provided. A nozzle plate provided with nozzle openings for ejecting liquid;
A flow path forming substrate provided with a pressure generating chamber communicating with the nozzle opening;
Pressure generating means for causing a pressure change in the liquid in the pressure generating chamber;
A communication plate provided between the nozzle plate and the flow path forming substrate,
In the communication plate,
A communication path communicating the pressure generation chamber and the nozzle opening;
A circulation channel that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and
The nozzle plate is rather smaller than the communicating plate,
The nozzle plate is a liquid ejecting head that covers the circulation flow path and the communication path. A nozzle plate provided with nozzle openings for ejecting liquid;
A flow path forming substrate provided with a pressure generating chamber communicating with the nozzle opening;
Pressure generating means for causing a pressure change in the liquid in the pressure generating chamber;
A communication plate provided between the nozzle plate and the flow path forming substrate,
In the communication plate,
A communication path communicating the pressure generation chamber and the nozzle opening;
A circulation channel that communicates the communication passage and a common liquid chamber that communicates in common with the plurality of pressure generation chambers, and
The nozzle plate is rather smaller than the communicating plate,
The flow path forming substrate is provided with at least two rows in which the pressure generation chambers are arranged in parallel, and the circulation flow path is provided as a common liquid chamber communicating with the two rows of the pressure generation chambers. Liquid ejecting head. The liquid ejecting head according to claim 6 , wherein the nozzle plate covers the circulation flow path and the communication path. The flow path forming substrate is in communication with the circulation flow path, according to any one of claims 5-7, characterized in that the extended portion to widen the sectional area of the circulation flow path is provided Liquid jet head. The common liquid chamber, said defined by communication plate, a liquid ejecting head according to any one of claims 1 to 8, characterized in that not defined by the nozzle plate. A liquid ejecting apparatus comprising the liquid ejecting head according to any one of claims 1 to 9.

Images