JP2017065001A - Flow path member for liquid discharge head, and liquid discharge head and recording apparatus using the same - Google Patents

Abstract

A flow path member for a liquid discharge head in which deterioration of discharge characteristics due to inflow of an adhesive into the flow path is reduced, and a liquid discharge head and a recording apparatus using the same are provided.
A flow path member 4 for a liquid discharge head has a plurality of discharge holes 8, a plurality of individual flow paths 12, and a manifold 5. Each of the individual flow paths 12 extends from the manifold 5 to the discharge holes 8. The pressurizing chamber 10 provided in the middle of the route to which the pressurizing chamber 10 is connected and the pressurizing chamber 10 and the manifold 5 are connected to each other. And a supply channel 6b having a channel resistance smaller than that of the squeezing body 6a. The supply channel 6b has an inner wall surface of the supply channel 6b and a cross section of the supply channel 6b. It has a step that changes.
[Selection] Figure 5

Description

  The present invention relates to a flow path member for a liquid discharge head, a liquid discharge head using the same, and a recording apparatus.

  Conventionally, as a liquid ejection head, for example, an inkjet head that performs various types of printing by ejecting a liquid onto a recording medium is known. As a flow path member having a discharge hole, a pressurizing chamber, and a common flow path used for a liquid discharge head, a plurality of metal plates having holes and grooves to be flow paths are stacked and bonded with an adhesive. Things are known. The metal plates are joined with an adhesive. In the metal plate, an adhesive relief groove is formed in order to prevent the adhesive from flowing into the hole or groove during bonding (see, for example, Patent Document 1).

JP 2002-67345 A

  However, in the above-described conventional liquid discharge head, when the metal plate is bonded with the adhesive, the adhesive flows into the hole or groove of the metal plate that becomes the flow path of the liquid, and the discharge characteristics such as the discharge amount and the discharge speed. There was a problem of worsening.

  An object of the present invention is to provide a flow path member for a liquid discharge head in which deterioration of discharge characteristics due to the inflow of an adhesive into the flow path is reduced, and a liquid discharge head and a recording apparatus using the same. is there.

  The flow path member for a liquid discharge head according to the present invention is configured by laminating a plurality of plates with an adhesive layer interposed therebetween, and corresponds to each of the plurality of discharge holes for discharging liquid and each of the discharge holes. A plurality of individual channels connected to the corresponding discharge holes, and a common channel connected to the plurality of individual channels, each of the individual channels Has a pressurizing chamber provided in the middle of a path from the common flow path to the discharge hole in the individual flow path, and a squeezing connecting the pressurizing chamber and the common flow path. The squeezing body is formed so as to extend in a direction along the plate, and the squeezing body is formed so as to extend in the stacking direction of the plates, and connects the common flow path and the squeezing body. A supply flow path having a flow path resistance smaller than that of the squeezing body. Cage, the feed passage, the inner wall surface of the supply passage has a stepped cross-section of the supply passage is changed.

  The liquid discharge head of the present invention is provided corresponding to each of the flow path member for the liquid discharge head and the pressurizing chamber, and each of the plurality of pressurizing members applies pressure to the corresponding pressurizing chamber. And a pressure part.

  The recording apparatus of the present invention includes the liquid discharge head, a transport unit that transports a recording medium to the liquid discharge head, and a control unit that controls the liquid discharge head.

  The flow path member for a liquid discharge head according to the present invention can reduce deterioration of discharge characteristics due to the inflow of an adhesive into the flow path.

(A) is a side view of a recording apparatus including a flow path member for a liquid discharge head according to the first embodiment of the present invention, and (b) is a plan view. FIG. 2 is a plan view of a head body that is a main part of the liquid ejection head of FIG. 1. FIG. 3 is an enlarged view of a region surrounded by an alternate long and short dash line in FIG. FIG. 3 is an enlarged view of a region surrounded by an alternate long and short dash line in FIG. It is a longitudinal cross-sectional view along the VV line of FIG. It is a top view which shows typically the structure of the squeezing which the flow-path member shown in FIGS. It is a top view which shows typically the structure of the supply flow path in the drawing of FIG. It is a typical longitudinal cross-sectional view along the WW line of FIG. FIG. 9 is a plan view similar to FIG. 7 schematically showing the structure of a supply flow path in a flow path member for a liquid ejection head according to a second embodiment of the present invention. It is a typical longitudinal cross-sectional view along the XX line of FIG. FIG. 9 is a longitudinal sectional view similar to FIG. 8 schematically showing the structure of a supply flow path in a flow path member for a liquid ejection head according to a third embodiment of the present invention. It is a top view which shows typically the structure of the supply flow path in the flow path member for liquid discharge heads concerning 4th Embodiment of this invention. It is a top view which shows typically the structure of the supply flow path in the flow path member for liquid discharge heads concerning 5th Embodiment of this invention. It is a typical longitudinal cross-sectional view along the YY line of FIG.

(First embodiment)
FIG. 1A is a color inkjet printer 1 (hereinafter simply referred to as a printer), which is a recording apparatus including a flow path member for a liquid discharge head according to a first embodiment of the present invention and a liquid discharge head including the flow path member. 1A is a schematic side view, and FIG. 1B is a schematic plan view. The printer 1 moves the print paper P relative to the liquid ejection head 2 by transporting the print paper P as a recording medium from the guide roller 82 </ b> A to the transport roller 82 </ b> B. The control unit 88 controls the liquid ejection head 2 based on image and character data, ejects liquid toward the recording medium P, causes droplets to land on the printing paper P, and prints on the printing paper P. Record such as.

  In this embodiment, the liquid ejection head 2 is fixed to the printer 1 and the printer 1 is a so-called line printer. However, the liquid ejection head 2 is arranged in a direction that intersects the transport direction of the printing paper P, for example, Alternatively, a so-called serial printer that alternately moves the printing paper P by reciprocating in a substantially orthogonal direction may be used.

A flat head mounting frame 70 (hereinafter sometimes simply referred to as a frame) is fixed to the printer 1 so as to be substantially parallel to the printing paper P. The frame 70 is provided with 20 holes (not shown), and the 20 liquid discharge heads 2 are mounted in the respective hole portions, and the portion of the liquid discharge head 2 that discharges the liquid is the printing paper P. It has come to face. The distance between the liquid ejection head 2 and the printing paper P is, for example, about 0.5 to 20 mm. The five liquid ejection heads 2 constitute one head group 72, and the printer 1 has four head groups 72.

  The liquid discharge head 2 has a long and narrow shape in the direction from the front to the back in FIG. 1A and in the vertical direction in FIG. This long direction is sometimes called the longitudinal direction. Within one head group 72, the three liquid ejection heads 2 are arranged along a direction that intersects the conveyance direction of the printing paper P, for example, a substantially orthogonal direction, and the other two liquid ejection heads 2 are conveyed. One of the three liquid ejection heads 2 is arranged at a position shifted along the direction. The liquid discharge heads 2 are arranged so that the printable range of each liquid discharge head 2 is connected in the width direction of the print paper P (in the direction intersecting the conveyance direction of the print paper P) or the ends overlap. Thus, printing without gaps in the width direction of the printing paper P is possible.

  The four head groups 72 are arranged along the conveyance direction of the recording paper P. A liquid, for example, ink is supplied to each liquid ejection head 2 from a liquid tank (not shown). The liquid discharge heads 2 belonging to one head group 72 are supplied with the same color ink, and the four head groups 72 can print four color inks. The colors of ink ejected from each head group 72 are, for example, magenta (M), yellow (Y), cyan (C), and black (K). A color image can be printed by printing such ink under the control of the control unit 88.

  The number of the liquid discharge heads 2 mounted on the printer 1 may be one if it is a single color and the range that can be printed by one liquid discharge head 2 is printed. The number of liquid ejection heads 2 included in the head group 72 and the number of head groups 72 can be changed as appropriate according to the printing target and printing conditions. For example, the number of head groups 72 may be increased in order to perform multicolor printing. Also, if a plurality of head groups 72 that print in the same color are arranged and printed alternately in the transport direction, the transport speed can be increased even if the liquid ejection heads 2 having the same performance are used. Thereby, the printing area per time can be increased. Alternatively, a plurality of head groups 72 for printing in the same color may be prepared and arranged so as to be shifted in a direction crossing the transport direction, so that the resolution in the width direction of the print paper P may be increased.

  Further, in addition to printing colored inks, a liquid such as a coating agent may be printed for surface treatment of the printing paper P.

  The printer 1 performs printing on a printing paper P that is a recording medium. The printing paper P is wound around the paper feed roller 80A, passes between the two guide rollers 82A, passes through the lower side of the liquid ejection head 2 mounted on the frame 70, and thereafter It passes between the two conveying rollers 82B and is finally collected by the collecting roller 80B. When printing, the printing paper P is transported at a constant speed by rotating the transport roller 82 </ b> B and printed by the liquid ejection head 2. The collection roller 80B winds up the printing paper P sent out from the conveyance roller 82B. The conveyance speed is, for example, 75 m / min. Each roller may be controlled by the controller 88 or may be manually operated by a person.

  In addition to the printing paper P, the recording medium may be a roll-like cloth. Further, instead of directly transporting the printing paper P, the printer 1 may transport the transport belt directly and transport the recording medium placed on the transport belt. By doing so, sheets, cut cloth, wood, tiles and the like can be used as the recording medium. Furthermore, a wiring pattern of an electronic device may be printed by discharging a liquid containing conductive particles from the liquid discharge head 2. Still further, the chemical may be produced by discharging a predetermined amount of liquid chemical agent or liquid containing the chemical agent from the liquid discharge head 2 toward the reaction container or the like and reacting.

In addition, a position sensor, a speed sensor, a temperature sensor, and the like may be attached to the printer 1, and the control unit 88 may control each part of the printer 1 according to the state of each part of the printer 1 that can be understood from information from each sensor. . For example, the temperature of the liquid discharge head 2, the temperature of the liquid in the liquid tank, the pressure applied by the liquid in the liquid tank to the liquid discharge head 2, etc. affect the discharge characteristics such as the discharge amount and discharge speed of the discharged liquid. For example, the drive signal for ejecting the liquid may be changed according to the information.

  Next, the liquid discharge head 2 will be described. FIG. 2 is a plan view showing a head main body 2a which is a main part of the liquid ejection head 2 shown in FIG. FIG. 3 is an enlarged plan view of a region surrounded by a one-dot chain line in FIG. 2, and is a part of the head main body 2a. In FIG. 3, for the sake of explanation, some of the flow paths are omitted. FIG. 4 is an enlarged plan view at the same position as FIG. 3, and a part of the flow path different from FIG. 3 is omitted. FIG. 5 is a longitudinal sectional view taken along line VV in FIG. 3 and 4, in order to make the drawings easy to understand, the pressurizing chamber 10, the squeezing 6, the discharge hole 8, and the like that are to be drawn by broken lines below the piezoelectric actuator substrate 21 are drawn by solid lines.

  In addition to the head main body 2a, the liquid discharge head 2 may include a reservoir for supplying liquid to the head main body 2a and a housing. The head body 2a includes a flow path member 4 and a piezoelectric actuator substrate 21 in which a displacement element 30 that is a pressurizing unit is formed.

  The flow path member 4 constituting the head body 2a includes a manifold 5 which is a common flow path, a plurality of pressurizing chambers 10 connected to the manifold 5, and a plurality of discharge holes respectively connected to the plurality of pressurizing chambers 10. 8 and. The pressurizing chamber 10 opens to the upper surface of the flow path member 4, and the upper surface of the flow path member 4 is a pressurizing chamber surface 4-2. Further, the upper surface of the flow path member 4 has an opening 5a which is an end of the manifold 5, and the liquid is supplied to the manifold 5 through the opening 5a.

  In addition, a piezoelectric actuator substrate 21 including a displacement element 30 is joined to the upper surface of the flow path member 4, and each displacement element 30 is disposed on the pressurizing chamber 10. The piezoelectric actuator substrate 21 is connected to a signal transmission unit 60 that supplies a signal to each displacement element 30. In FIG. 2, the outline of the vicinity of the signal transmission unit 60 connected to the piezoelectric actuator substrate 21 is indicated by a dotted line so that the two signal transmission units 60 are connected to the piezoelectric actuator substrate 21. The electrodes formed on the signal transmission unit 60 that are electrically connected to the piezoelectric actuator substrate 21 are arranged in a rectangular shape at the end of the signal transmission unit 60. The two signal transmission parts 60 are connected so that each end comes to the center part in the short direction of the piezoelectric actuator substrate 21.

  The head main body 2 a has one piezoelectric actuator substrate 21 including a flat plate-like channel member 4 and a displacement element 30 joined on the channel member 4. The planar shape of the piezoelectric actuator substrate 21 is rectangular, and is arranged on the upper surface of the flow path member 4 so that the long side of the rectangle is along the longitudinal direction of the flow path member 4.

  Two manifolds 5 are formed inside the flow path member 4. The manifold 5 has an elongated shape extending from one end side in the longitudinal direction of the flow path member 4 to the other end side, and the opening of the manifold 5 that opens to the upper surface of the flow path member 4 at both ends thereof. 5a is formed.

The manifold 5 is partitioned by a partition wall 15 provided at an interval in the short-side direction at least in the central portion in the longitudinal direction, which is a region connected to the pressurizing chamber 10. The partition wall 15 has the same height as the manifold 5 in the central portion in the longitudinal direction, which is a region connected to the pressurizing chamber 10, and completely separates the manifold 5 into a plurality of sub-manifolds 5b. By doing so, it is possible to provide the discharge hole 8 and the flow path connected from the discharge hole 8 to the pressurizing chamber 10 so as to overlap with the partition wall 15 in a plan view.

  The portion of the manifold 5 divided into a plurality of parts may be referred to as a sub-manifold 5b. In the present embodiment, two manifolds 5 are provided independently, and openings 5a are provided at both ends. One manifold 5 is provided with seven partition walls 15 and divided into eight sub-manifolds 5b. The width of the sub-manifold 5b is larger than the width of the partition wall 15, so that a large amount of liquid can flow through the sub-manifold 5b.

  The flow path member 4 is formed by two-dimensionally expanding a plurality of pressurizing chambers 10. The pressurizing chamber 10 is a hollow region having a substantially rhombic or elliptical planar shape with rounded corners.

  The pressurizing chamber 10 is connected to one sub-manifold 5 b through the throttle 6. Along with one sub-manifold 5b, two pressurizing chamber rows 11, which are rows of pressurizing chambers 10 connected to the sub-manifold 5b, are provided on each side of the sub-manifold 5b, for a total of two rows. Yes. Accordingly, 16 rows of pressurizing chambers 11 are provided for one manifold 5, and 32 heads of pressurizing chambers 11 are provided in the entire head body 2a. The intervals in the longitudinal direction of the pressurizing chambers 10 in the respective pressurizing chamber rows 11 are the same, for example, 37.5 dpi.

  One column of dummy pressurizing chambers 16 is provided at the end of each pressurizing chamber row 11. The dummy pressurizing chambers 16 in the dummy pressurizing chamber row are connected to the manifold 5 but are not connected to the discharge holes 8. Further, one dummy pressurizing chamber row in which dummy pressurizing chambers 16 are arranged in a straight line is provided outside the 32 pressurizing chamber rows 11. The dummy pressurizing chamber 16 in this dummy pressurizing chamber row is not connected to either the manifold 5 or the discharge hole 8. By these dummy pressurizing chambers 16, the structure (rigidity) around the pressurizing chamber 10 one inner side from the end is close to the structure (rigidity) of the other pressurizing chambers 10, so that the difference in liquid ejection characteristics can be reduced. Less. In addition, since the influence of the surrounding structure difference has a large influence on the pressurizing chambers 10 adjacent to each other in the length direction, the dummy pressurizing chambers are provided at both ends in the length direction. Since the influence in the width direction is relatively small, it is provided only on the side closer to the end of the head main body 21a. Thereby, the width | variety of the head main body 21a can be made small.

  The pressurizing chambers 10 connected to one manifold 5 are arranged in a lattice form having rows and columns along each outer side of the rectangular piezoelectric actuator substrate 21. As a result, the individual electrodes 25 formed on the pressurizing chamber 10 are arranged at equal distances from the outer side of the piezoelectric actuator substrate 21. Therefore, when forming the individual electrodes 25, the piezoelectric actuator substrate is formed. 21 can be hardly deformed. When the piezoelectric actuator substrate 21 and the flow path member 4 are joined, if this deformation is large, stress may be applied to the displacement element 30 near the outer side, resulting in variations in displacement characteristics. However, by reducing the deformation, The variation can be reduced. In addition, since the dummy pressurizing chamber row of the dummy pressurizing chamber 16 is provided outside the pressurizing chamber row 11 closest to the outer side, the influence of deformation can be made less susceptible. The pressurizing chambers 10 belonging to the pressurizing chamber row 11 are arranged at equal intervals, and the individual electrodes 25 corresponding to the pressurizing chamber rows 11 are also arranged at equal intervals. The pressurizing chamber rows 11 are arranged at equal intervals in the short direction, and the rows of the individual electrodes 25 corresponding to the pressurizing chamber rows 11 are also arranged at equal intervals in the short direction. Thereby, it is possible to eliminate a portion where the influence of the crosstalk becomes particularly large.

In the present embodiment, the pressurizing chambers 10 are arranged in a lattice shape, but the pressurizing chambers 10 of adjacent pressurizing chamber rows 11 may be arranged in a staggered manner so as to be positioned between each other. In this way, since the distance between the pressurizing chambers 10 belonging to the adjacent pressurizing chamber row 11 becomes longer, crosstalk can be further suppressed.

  Regardless of how the pressurizing chamber rows 11 are arranged, when the flow path member 4 is viewed in plan, the pressurizing chamber 10 belonging to one pressurizing chamber row 11 is added to the adjacent pressurizing chamber row 11. By arranging the pressure chamber 10 and the liquid discharge head 2 so as not to overlap in the longitudinal direction, crosstalk can be suppressed. On the other hand, when the distance between the pressurizing chamber rows 11 is increased, the width of the liquid discharge head 2 is increased, so that the accuracy of the installation angle of the liquid discharge head 2 relative to the printer 1 and the use of a plurality of liquid discharge heads 2 are increased. The influence of the relative position accuracy of the liquid discharge head 2 on the printing result is increased. Therefore, by making the width of the partition wall 15 smaller than that of the sub-manifold 5b, the influence of the accuracy on the printing result can be reduced.

  The pressurizing chamber 10 connected to one sub-manifold 5 b forms two rows of pressurizing chamber rows 11, and the discharge holes 8 connected to the pressurizing chambers 10 belonging to one pressurizing chamber row 11 are One discharge hole row 9 is formed. The discharge holes 8 connected to the pressurizing chambers 10 belonging to the two pressurizing chamber rows 11 open to different sides of the sub-manifold 5b. In FIG. 4, two discharge hole rows 9 are provided in the partition wall 15, but the discharge holes 8 belonging to each discharge hole row 9 are connected to the sub-manifold 5 b on the side close to the discharge holes 8 in the pressurizing chamber 10. Are connected through. When the discharge hole 8 connected to the adjacent sub-manifold 5b via the pressurizing chamber row 11 and the liquid discharge head 2 are arranged so as not to overlap in the longitudinal direction, the pressurizing chamber 10 and the discharge hole 8 are connected. Since crosstalk between the flow paths can be suppressed, crosstalk can be further reduced. If the entire flow path connecting the pressurizing chamber 10 and the discharge hole 8 is arranged so as not to overlap in the longitudinal direction of the liquid discharge head 2, crosstalk can be further reduced.

  A plurality of pressurizing chambers are formed by a plurality of pressurizing chambers 10 connected to one manifold 5. Since there are two manifolds 5, there are two pressurizing chamber groups. The arrangement of the pressurizing chambers 10 related to ejection in each pressurizing chamber group is the same, and is arranged at a position translated in the short direction. These pressurizing chambers 10 are arranged over almost the entire surface although there are portions where the gaps between the pressurizing chamber groups are slightly wide in the region facing the piezoelectric actuator substrate 21 on the upper surface of the flow path member 4. . That is, the pressurizing chamber group formed by these pressurizing chambers 10 occupies a region having almost the same shape as the piezoelectric actuator substrate 21. Further, the opening of each pressurizing chamber 10 is closed by bonding the piezoelectric actuator substrate 21 to the upper surface of the flow path member 4.

  From the corner portion of the pressurizing chamber 10 facing the corner portion to which the squeezing 6 is connected, the flow channel connected to the discharge hole 8 opened on the discharge hole surface 4-1 on the lower surface of the flow channel member 4 extends. . This flow path extends in a direction away from the pressurizing chamber 10 in a plan view. More specifically, the pressurizing chamber 10 extends away from the direction along the long diagonal line while being shifted to the left and right with respect to that direction. As a result, the discharge chambers 8 can be arranged at intervals of 1200 dpi as a whole, while the pressurization chambers 10 are arranged in a lattice pattern in which the intervals within the pressurization chamber rows 11 are 37.5 dpi.

In other words, when the discharge holes 8 are projected so as to be orthogonal to the virtual straight line parallel to the longitudinal direction of the flow path member 4, each manifold 5 is within the range of R of the virtual straight line shown in FIG. That is, 16 discharge holes 8 connected to, and a total of 32 discharge holes 8 are equally spaced by 1200 dpi. Thus, by supplying the same color ink to all the manifolds 5, an image can be formed with a resolution of 1200 dpi in the longitudinal direction as a whole. Further, one discharge hole 8 connected to one manifold 5 is equally spaced at 600 dpi within the range of R of the imaginary straight line. As a result, by supplying different colors of ink to the respective manifolds 5, it is possible to form two-color images with a resolution of 600 dpi in the longitudinal direction as a whole. In this case, if two liquid ejection heads 2 are used, an image of four colors can be formed with a resolution of 600 dpi, and printing accuracy is higher than when four liquid ejection heads capable of printing at 600 dpi are used. Can also be done easily. In addition, the range of R of the imaginary straight line is covered with the discharge holes 8 connected to the pressurizing chambers 10 belonging to the one pressurizing chamber row arranged in the short direction of the head main body 2a.

  Individual electrodes 25 are formed at positions facing the pressurizing chambers 10 on the upper surface of the piezoelectric actuator substrate 21. The individual electrode 25 includes an individual electrode main body 25a that is slightly smaller than the pressurizing chamber 10 and has a shape substantially similar to the pressurizing chamber 10, and an extraction electrode 25b that is extracted from the individual electrode main body 25a. In the same manner as the pressurizing chamber 10, the individual electrode 25 constitutes an individual electrode row and an individual electrode group. A common electrode surface electrode 28 is disposed on the upper surface of the piezoelectric actuator substrate 21. The common electrode surface electrode 28 and the common electrode 24 are electrically connected through a through conductor (not shown) disposed in the piezoelectric ceramic layer 21b.

  The discharge hole 8 is disposed at a position avoiding a region facing the manifold 5 disposed on the lower surface side of the flow path member 4. Further, the discharge hole 8 is disposed in a region facing the piezoelectric actuator substrate 21 on the lower surface side of the flow path member 4. These discharge holes 8 occupy a region having almost the same shape as the piezoelectric actuator substrate 21 as one group, and a droplet is discharged from the discharge hole 8 by displacing the displacement element 30 of the corresponding piezoelectric actuator substrate 21. Can be discharged.

  The flow path member 4 included in the head main body 2a has a laminated structure in which a plurality of plates are laminated with an adhesive layer 18 interposed therebetween. These plates are, in order from the upper surface of the flow path member 4, a plate 4a, a plate 4b, a plate 4c, a plate 4d, a plate 4e, a plate 4f, a plate 4g, a plate 4h, a plate 4i, a plate 4j, a plate 4k, and a plate 4m. They are stacked in order. A number of holes are formed in these plates. Since the thickness of each plate is about 10 to 300 μm, the hole formation accuracy can be increased. The thickness of the flow path member 4 is about 500 μm to 2 mm. Each plate is aligned and laminated so that these holes communicate with each other to form the individual flow path 12 and the manifold 5. In the head body 2a, the pressurizing chamber 10 is on the upper surface of the flow path member 4, the manifold 5 is on the inner lower surface side, and the discharge holes 8 are on the lower surface. The manifold 5 and the discharge hole 8 are connected via the pressurizing chamber 10.

  The hole and groove | channel arrange | positioned at each plate are demonstrated.

  The following holes and grooves are used as the flow path. The first is a hole that becomes the pressurizing chamber 10 formed in the plate 4a. Secondly, there is a communication hole that forms a squeeze 6 that connects from one end of the pressurizing chamber 10 to the manifold 5. This communication hole is formed in each plate from the plate 4b (specifically, the inlet of the pressurizing chamber 10) to the plate 4e (specifically, the outlet of the manifold 5).

  Third, the descender 7 constitutes a flow path that communicates with the discharge hole 8 from the end opposite to the end to which the throttle 6 of the pressurizing chamber 10 is connected. The descender 7 is formed on each plate from the plate 4b (specifically, the outlet of the pressurizing chamber 10) to the plate 4m (specifically, the discharge hole 8).

  Fourthly, communication holes constituting the manifold (common flow path) 5. The communication holes are formed in the plates 4a to 4j. Holes are formed in the plates 4f to 4j so that the partition portions that become the partition walls 15 remain so as to constitute the sub-manifold 5b. The partition portions in the plates 4f to 4j are connected to the plates 4f to 4j by half-etched support portions (not shown in the drawing).

These first to fourth holes are connected to each other to form a flow path from the opening 5 a of the manifold 5 to the discharge hole 8. Further, the individual flow path 12 extending from the manifold 5 (more precisely, the sub-manifold 5b) to the discharge hole 8 is constituted by the first to third holes. The liquid supplied to the opening 5 a of the manifold 5 passes through the manifold 5, the aperture 6, the pressurizing chamber 10, and the descender 7 and is discharged to the outside from the discharge hole 8.

The piezoelectric actuator substrate 21 has a laminated structure composed of two piezoelectric ceramic layers 21a and 21b which are piezoelectric bodies. Each of these piezoelectric ceramic layers 21a and 21b has a thickness of about 20 μm. The thickness from the lower surface of the piezoelectric ceramic layer 21a of the piezoelectric actuator substrate 21 to the upper surface of the piezoelectric ceramic layer 21b is about 40 μm. Both of the piezoelectric ceramic layers 21 a and 21 b extend so as to straddle the plurality of pressure chambers 10. The piezoelectric ceramic layers 21a, 21b may, for example, strength with a dielectric, lead zirconate titanate (PZT), NaNbO ₃ system, BaTiO ₃ system, (BiNa) NbO ₃ system, such as BiNaNb ₅ O ₁₅ system Made of ceramic material. The piezoelectric ceramic layer 21a functions as a vibration plate and does not necessarily have to be a piezoelectric body. Instead, other ceramic layers or metal plates that are not piezoelectric bodies may be used.

  The piezoelectric actuator substrate 21 includes a common electrode 24 made of a metal material such as Ag—Pd and an individual electrode 25 made of a metal material such as Au. The common electrode 24 has a thickness of about 2 μm, and the individual electrode 25 has a thickness of about 1 μm.

  The individual electrodes 25 are respectively arranged at positions facing the pressurizing chambers 10 on the upper surface of the piezoelectric actuator substrate 21. The individual electrode 25 has a planar shape slightly smaller than that of the pressurizing chamber main body 10a and has a shape substantially similar to the pressurizing chamber main body 10a, and an extraction electrode drawn from the individual electrode main body 25a. 25b. A connection electrode 26 is disposed at a portion of one end of the extraction electrode 25 b that is extracted outside the region facing the pressurizing chamber 10. The connection electrode 26 is a conductive resin containing conductive particles such as silver particles, and is formed with a thickness of about 5 to 200 μm. Further, the connection electrode 26 is electrically joined to an electrode provided in the signal transmission unit 60.

  Although details will be described later, a drive signal is supplied from the control unit 88 to the individual electrode 25 through the signal transmission unit 60. The drive signal is supplied in a constant cycle in synchronization with the conveyance speed of the print medium P.

  The common electrode 24 is formed over substantially the entire surface in the region between the piezoelectric ceramic layer 21b and the piezoelectric ceramic layer 21a. That is, the common electrode 24 extends so as to cover all the pressurizing chambers 10 in the region facing the piezoelectric actuator substrate 21. The common electrode 24 is connected to the common electrode surface electrode 28 formed on the piezoelectric ceramic layer 21b so as to avoid the electrode group composed of the individual electrodes 44 via a through conductor formed through the piezoelectric ceramic layer 21b. It is connected. Further, the common electrode 24 is grounded via the common electrode surface electricity 28 and is held at the ground potential. Similar to the individual electrode 25, the common electrode surface electrode 28 is directly or indirectly connected to the control unit 88.

A portion sandwiched between the individual electrode 25 and the common electrode 24 of the piezoelectric ceramic layer 21b is polarized in the thickness direction, and becomes a displacement element 30 having a unimorph structure that is displaced when a voltage is applied to the individual electrode 25. Yes. More specifically, when an electric field is applied in the polarization direction to the piezoelectric ceramic layer 21b by setting the individual electrode 25 to a potential different from that of the common electrode 24, an active portion where the applied electric field is distorted by the piezoelectric effect. Work as. In this configuration, when the control unit 88 sets the individual electrode 25 to a predetermined positive or negative potential with respect to the common electrode 24 so that the electric field and the polarization are in the same direction, the portion sandwiched between the electrodes of the piezoelectric ceramic layer 21b. (Active part) contracts in the surface direction. On the other hand, the piezoelectric ceramic layer 21a, which is an inactive layer, is not affected by an electric field, so that it does not spontaneously shrink and tries to restrict deformation of the active portion. As a result, there is a difference in strain in the polarization direction between the piezoelectric ceramic layer 21a and the piezoelectric ceramic layer 21b, and the piezoelectric ceramic layer 21a is deformed so as to be convex toward the pressurizing chamber 10 (unimorph deformation).

  Next, the liquid discharge operation will be described. The displacement element 30 is driven (displaced) by a drive signal supplied to the individual electrode 25 through a driver IC or the like under the control of the control unit 88. In the present embodiment, liquid can be ejected by various driving signals. Here, a so-called strike driving method will be described.

  The individual electrode 25 is set to a potential higher than the common electrode 24 (hereinafter referred to as a high potential) in advance, and the individual electrode 25 is once set to the same potential as the common electrode 24 (hereinafter referred to as a low potential) each time there is a discharge request, and then a predetermined potential is set. At this timing, the potential is set again. Thereby, the piezoelectric ceramic layers 21a and 21b return to the original (flat) shape at the timing when the individual electrode 25 becomes low potential (beginning), and the volume of the pressurizing chamber 10 is in the initial state (the potentials of both electrodes are different) Increase compared to the state). As a result, a negative pressure is applied to the liquid in the pressurizing chamber 10. Then, the liquid in the pressurizing chamber 10 starts to vibrate with the natural vibration period. Specifically, first, the volume of the pressurizing chamber 10 begins to increase, and the negative pressure gradually decreases. Next, the volume of the pressurizing chamber 10 becomes maximum and the pressure becomes almost zero. Next, the volume of the pressurizing chamber 10 begins to decrease, and the pressure increases. Thereafter, the individual electrode 25 is set to a high potential at a timing at which the pressure becomes substantially maximum. Then, the first applied vibration overlaps with the next applied vibration, and a larger pressure is applied to the liquid. This pressure propagates through the descender 7 to discharge the liquid from the discharge hole 8.

In other words, a droplet can be ejected by supplying a pulse driving signal that is a low potential for a certain period with the high potential as a reference to the individual electrode 25. If this pulse width is AL (Acoustic Length), which is half the time of the natural vibration period of the liquid in the pressurizing chamber 10, in principle, the discharge speed and discharge amount of the liquid can be maximized. The natural vibration period of the liquid in the pressurizing chamber 10 is greatly affected by the physical properties of the liquid and the shape of the pressurizing chamber 10, but besides that, the physical properties of the piezoelectric actuator substrate 21 and the flow path connected to the pressurizing chamber 10 Also affected by the characteristics of.

  Note that the pulse width is actually set to a value of about 0.5 AL to 1.5 AL because there are other factors to consider, such as combining the ejected droplets into one. Further, since the discharge amount can be reduced by setting the pulse width to a value outside of AL, the pulse width is set to a value outside of AL in order to reduce the discharge amount.

  Next, the aperture 6 included in the flow path member 4 of the present embodiment will be described with reference to FIGS. FIG. 5 is a longitudinal sectional view taken along the line VV in FIG. 3 and schematically shows the structure of the individual flow path 12 extending from the manifold 5 (sub-manifold 5 b) to the discharge hole 8. FIG. 6 is a plan view schematically showing the structure of the aperture 6 included in the individual flow path 12. FIG. 7 is a partial plan view schematically showing the structure of the supply flow path 6b included in the aperture 6 of FIG. FIG. 8 is a schematic longitudinal sectional view taken along line WW in FIG.

  The squeezing 6 is a flow path that connects the manifold 5 (more precisely, the sub-manifold 5b) and the pressurizing chamber 10, and in striking, the pressure applied to the pressurizing chamber 10 is reflected and discharged is increased. It is a part that plays a role to perform, and high and accurate flow path resistance is required. When the flow path resistance of the squeezing 6 is reduced, the pressure wave generated in one individual flow path 12 (more precisely, the pressurizing chamber 10) is transmitted to the other individual flow path 12 via the manifold 5, If the discharge characteristics deteriorate due to the crosstalk and the flow path resistance of the throttle 6 is too high, the amount of liquid supplied from the manifold 5 to the individual flow path 12 decreases. For this reason, the squeezing 6 is required to have a relatively high and accurate flow path resistance even if it is a discharge method other than drawing.

  The squeezing 6 is constituted by a squeezing main body 6a, a supply channel 6b, and a discharge channel 6c. The squeezing main body 6a is a portion extending in a direction along the plate 4c (a direction along both main surfaces of the plate 4c). Since the squeezing body 6a is disposed on the plate 4c having a smaller thickness than the other plates, the height of the flow path (the dimension in the plate stacking direction) is small, and the width of the flow path is also narrow. Compared with other portions, the cross-sectional area is small. That is, the restriction body 6 a is a part that has a high flow resistance and determines the flow resistance of the restriction 6. Further, as shown in FIG. 6, the squeezing body 6a is a linear portion having a particularly narrow channel width, and a portion connected to the supply channel 6b and the discharge channel 6c provided at both ends thereof. And a relatively wide portion.

  The discharge flow path 6 c is a flow path that is disposed on the plate 4 c and extends in the plate stacking direction, and connects the narrowing body 6 a and the pressurizing chamber 10. The discharge flow path 6c has a cross-sectional area larger than that of the squeezed main body 6a and a flow path resistance smaller than that of the squeezed main body 6a.

  The supply flow path 6b extends from the plate 4d to the plate 4e in the plate stacking direction, and is a flow path that connects the manifold 5 (sub-manifold 5b) and the narrow body 6a. The supply flow path 6b has a cross-sectional area larger than that of the squeezed main body 6a and a flow path resistance smaller than that of the squeezed main body 6a. The supply flow path 6b includes a first supply flow path 6b1 disposed on the plate 4e and a second supply flow path 6b2 disposed on the plate 4d. That is, the supply flow path 6b includes a first supply flow path 6b1 positioned on the manifold 5 side and a second supply flow path 6b2 positioned on the side of the narrowing body 6a. Both the first supply channel 6b1 and the second supply channel 6b2 have a circular cross-sectional shape. And the area of the cross section of the 1st supply flow path 6b1 is made larger than the area of the cross section of the 2nd supply flow path 6b2, and the 1st supply flow path 6b1 and 2nd in the inner wall surface of the supply flow path 6b At the boundary with the supply flow path 6b2, there is a step 6d in which the cross-sectional area changes. When viewed in plan from the plate stacking direction, the second supply channel 6b2 is located at the center of the first supply channel 6b1, and a step 6d is formed so as to surround the second supply channel 6b2. Yes.

  As described above, the flow path member for the liquid ejection head according to the present embodiment is configured by laminating the plurality of plates 4a to 4m via the adhesive layer (not shown). Further, the flow path member for the liquid discharge head of the present embodiment is provided corresponding to each of the plurality of discharge holes 8 for discharging liquid and the discharge holes 8, and each is connected to the corresponding discharge hole 8. A plurality of individual flow paths 12 and a common flow path (manifold 5) to which the plurality of individual flow paths 12 are connected. Each individual flow path 12 includes a pressurizing chamber 10 provided in the middle of a path from the manifold 5 (more precisely, the sub-manifold 5b) to the discharge hole 8 in the individual flow path 12, and the pressurizing chamber 10 and the manifold 5 And a squeeze 6 that connects the two. The squeezing 6 has a squeezing main body 6a and a supply flow path 6b. The squeezing body 6a is formed so as to extend in a direction along the plate. The supply channel 6b is formed so as to extend in the stacking direction of the plates, and connects the manifold 5 and the squeezing body 6a, and has a channel resistance smaller than that of the squeezing body 6a. Further, the supply flow path 6b has a step 6d on the inner wall surface of the supply flow path 6b where the cross section of the supply flow path 6b changes. The flow path member for the liquid discharge head of the present embodiment having such a configuration is that the adhesive adhered to the inner wall surface of the manifold 5 (sub-manifold 5b) flows into the squeezed main body 6a and deteriorates the discharge characteristics. Can be reduced.

  In the production of the flow path member 4, when the plates 4 a to 4 m are laminated through the adhesive layer, if the amount of the adhesive does not reach the entire surface between the plates 4 a to 4 m, there is a portion that is not bonded. Will occur. When pressure is applied for bonding in a state where the adhesive is spread over the entire surface between the plates 4a to 4m, a part of the adhesive flows into the flow path. Therefore, in order to prevent the inflow of the adhesive, an adhesive relief groove is disposed around the hole or groove serving as the flow path.

  The periphery of the supply flow path 6b on the surface on the discharge hole surface 4-1 side of the plate 4e is the inner wall surface of the manifold 5 and is not a portion to be joined to another plate. However, patterning in the application of the adhesive is not practical because it causes adhesion failure and significantly increases the number of manufacturing steps and man-hours. Therefore, the periphery of the supply flow path 6b on the surface on the discharge hole surface 4-1 side of the plate 4e is also an adhesive application region. Furthermore, since the periphery of the supply flow path 6b on the surface on the discharge hole surface 4-1 side of the plate 4e is the inner wall surface of the manifold 5 and not a portion to be joined to other plates, the plates are pressed against each other. The adhesive does not move, but when heated to cure the adhesive, the viscosity of the adhesive decreases before curing, causing the adhesive to flow, and the adhesive flows into the supply channel 6b. It became clear by the inventors' examination.

  As described above, since the flow path resistance of the squeezing main body 6a has a great influence on the discharge characteristics, the inflow of the adhesive into the squeezing main body 6a greatly deteriorates the discharge characteristics. Further, since the main body 6a has a smaller cross-sectional area than other parts, the inflow of the adhesive to the main body 6a tends to block the flow path, which may lead to a fatal problem.

  As one method of preventing the adhesive from flowing into the supply flow path 6b, it is considered to provide an adhesive relief groove around the supply flow path 6b on the surface on the discharge hole surface 4-1 side of the plate 4e. It is done. However, the inventors have found that this method has a problem that air is trapped in the escape groove and hinders air discharge. There is also a problem that pressure waves leaking from the plurality of individual flow paths 12 are reflected by the escape grooves and adversely affect the discharge characteristics.

  The flow path member for the liquid discharge head according to the present embodiment having the above-described configuration causes the adhesive flowing into the first supply flow path 6b1 from the manifold 5 to flow into the step 6d (more precisely, the manifold 5 (sub-manifold at the step 6d). 5b) Since it can be trapped by the facing inner wall surface (inner wall surface parallel to the discharge hole surface 4-1, particularly its end), it prevents the adhesive from flowing into the squeezing body 6a and discharge characteristics. Can be prevented. For this reason, there is no need to provide an adhesive relief groove around the supply flow path 6b on the surface on the discharge hole surface 4-1 side of the plate 4e, and there is no escape groove around the supply flow path 6b on the inner wall surface of the manifold 5. It can be a non-forming region. Thereby, it is possible to prevent the occurrence of the above-mentioned problems due to the formation of the escape groove around the supply flow path 6b on the inner wall surface of the manifold 5.

  In the present embodiment, the area of the cross section of the second supply flow path 6b2 is smaller than the area of the cross section of the first supply flow path 6b1, and the supply flow path 6b is from the manifold 5 (common flow path) side. When heading toward the squeezed main body 6a, the area of the cross section becomes smaller with the step 6d as a boundary. For this reason, the flow of liquid from the manifold 5 to the supply flow path 6b can be made smooth, and the adhesive can be reliably trapped by the step 6d.

  In addition, it is desirable that the step 6d is formed so as to surround the second supply channel 6b2 when viewed in plan from the plate stacking direction, so that the adhesive can be reliably trapped. Further, the height of the step is desirably 50 μm or more, and more desirably 100 μm or more.

In the present embodiment, the first supply channel 6b1 is provided in the plate 4e, and the second supply channel 6b2 is provided in the plate 4d. That is, the manifold 5 (common flow path) side from the step 6d in the supply flow path 6b is configured by a through hole provided in one plate, and the squeezing main body 6a side from the step 6d in the supply flow path 6b is It is constituted by a through hole provided in another plate. Thereby, the level | step difference 6d can be easily formed in the inner wall face of the supply flow path 6b. However, it is not limited to this structure, You may provide the supply flow path 6b in one plate. In this case, for example, after forming a recess in one plate by half-etching, by forming a through hole in the recess, a step that changes the cross section of the supply channel 6b is formed in the supply channel 6b. It can be formed on the inner wall surface.

(Second Embodiment)
Next, a flow path member for a liquid discharge head according to a second embodiment of the present invention will be described with reference to FIGS. In addition, in this embodiment, a different point from the flow-path member 4 of 1st Embodiment mentioned above is demonstrated, and the overlapping description is abbreviate | omitted (a similar referential mark is attached | subjected to the same component). FIG. 9 is a plan view similar to FIG. 7 schematically showing the structure of the supply flow path 6b in the flow path member 4 for the liquid ejection head according to the second embodiment of the present invention. 10 is a schematic longitudinal sectional view taken along line XX in FIG.

  As shown in FIGS. 9 and 10, the flow path member 4 of the present embodiment further has a recess 6 f. Other configurations are the same as those of the flow path member 4 of the first embodiment. The recess 6f is provided on an inner wall surface (an inner wall surface parallel to the discharge hole surface 4-1) facing the manifold 5 (common flow path) in the step 6d. Since the flow path member 4 of the present embodiment has the recess 6f, the adhesive can be reliably trapped by the recess 6f while suppressing the height of the step 6d to be low.

  Further, in the present embodiment, when the supply flow path 6b is viewed from the manifold 5 side (discharge hole surface 4-1 side), the flow path (second supply flow path 6b2) on the side of the main body 6a that is narrower than the step 6d. A recess 6f is provided so as to surround the periphery with a gap. As a result, the adhesive can be reliably trapped by the recess 6f regardless of which direction the adhesive flows toward the second supply channel 6b2. The width of the recess 6f is desirably 50 μm or more. The depth of the recess 6f is preferably 40% or more and 60% or less of the depth of the plate 4e.

(Third embodiment)
Next, a flow path member for a liquid discharge head according to a second embodiment of the present invention will be described with reference to FIG. In addition, in this embodiment, a different point from the flow-path member 4 of 1st Embodiment mentioned above is demonstrated, and the overlapping description is abbreviate | omitted (a similar referential mark is attached | subjected to the same component). FIG. 11 is a longitudinal sectional view similar to FIG. 8 schematically showing the structure of the supply flow path 6b in the flow path member 6 for a liquid ejection head according to the third embodiment of the present invention.

  In the present embodiment, as shown in FIG. 11, the area of the cross section of the second supply channel 6b2 is larger than the area of the cross section of the first supply channel 6b1. That is, the supply flow path 6b has a larger cross-sectional area at the step 6d as a boundary when moving from the manifold 5 (common flow path) side to the squeezing main body 6a side. Also in the flow path member 4 having such a configuration, the step 6d (more precisely, the inner wall surface (the inner wall surface parallel to the pressure chamber surface 4-2) facing the squeezing main body 6a in the step 6d) Since the adhesive is trapped at the end), the adhesive can be prevented from flowing into the main body 6a.

  Further, since the area of the cross section of the supply channel 6b on the manifold 5 side (first supply channel 6b1) is small, the pressure wave generated in the other individual channels 12 and transmitted into the manifold 5 is supplied to the first supply channel 6b. Since it can reflect in the boundary part with the flow path 6b1, the deterioration of the discharge characteristic by crosstalk can be reduced.

(Fourth embodiment)
Next, a flow path member for a liquid ejection head according to a fourth embodiment of the present invention will be described with reference to FIG. In addition, in this embodiment, a different point from the flow-path member 4 of 1st Embodiment mentioned above is demonstrated, and the overlapping description is abbreviate | omitted (a similar referential mark is attached | subjected to the same component). FIG. 12 is a plan view schematically showing the structure of the supply flow path 6b in the flow path member 6 for a liquid ejection head according to the fourth embodiment of the present invention, as viewed in plan from the stacking direction of the plates 4a to 4m. Indicates the state.

  In the present embodiment, as shown in FIG. 12, the cross-sectional area of the first supply flow path 6b1 and the cross-sectional area of the second supply flow path 6b2 are equal, but the cross-section of the first supply flow path 6b1 Has a star-like shape with seven corners, and the cross section of the second supply channel 6b2 has a circular shape. Thereby, a step is formed at the boundary between the first supply channel 6b1 and the second supply channel 6b2 on the inner wall surface of the supply channel 6b. That is, the shape of the cross section of the supply flow path 6b changes from the manifold 5 (common flow path) side toward the squeezed main body 6a side with the step 6d as a boundary. Also in the flow path member 4 having such a configuration, a step (to be exact, the surface on the manifold 5 side in the portion where the first supply flow path 6b1 of FIG. 12 protrudes from the second supply flow path 6b2 and the surface of FIG. Adhesive is trapped at the surface of the main body 6a side of the second supply flow path 6b2 that protrudes from the first supply flow path 6b1, and the adhesive is trapped particularly at the end of the surface of the second supply flow path 6b2. Inflow of the agent can be prevented.

  In the present embodiment, since the cross section of the first supply flow path 6b1 has many corners, a certain amount of adhesive is trapped at the corner of the cross section of the first supply flow path 6b1. The effect of preventing the adhesive from flowing into the squeezed main body 6a can be enhanced.

  FIG. 12 shows the case where the cross-sectional area of the first supply channel 6b1 is equal to the cross-sectional area of the second supply channel 6b2, but the present invention is not limited to this. . The area of the cross section of the first supply flow path 6b1 is different from the area of the cross section of the second supply flow path 6b2, thereby increasing the height of the step, thereby allowing the adhesive to flow into the squeezing body 6a. The effect of preventing can be further enhanced.

(Fifth embodiment)
Next, a flow path member for a liquid discharge head according to a fifth embodiment of the present invention will be described with reference to FIGS. In addition, in this embodiment, a different point from the flow-path member 4 of 1st Embodiment mentioned above is demonstrated, and the overlapping description is abbreviate | omitted (a similar referential mark is attached | subjected to the same component). FIG. 13 is a plan view schematically showing the structure of the supply flow path 6b in the flow path member 4 for the liquid ejection head according to the second embodiment of the present invention, as viewed in plan from the stacking direction of the plates 4a to 4m. Indicates the state. 14 is a schematic longitudinal sectional view taken along line YY of FIG.

  In the present embodiment, as shown in FIG. 13 and FIG. 14, the cross section of the first supply flow path 6b1 and the cross section of the second supply flow path 6b2 are both circular and have the same cross-sectional area. When viewed in plan from the stacking direction of the plates 4a to 4m, the position of the center of gravity c1 of the cross section of the first supply channel 6b1 is different from the position of the center of gravity c2 of the cross section of the second supply channel 6b2. ing. As a result, a step 6d is formed at the boundary between the first supply channel 6b1 and the second supply channel 6b2 on the inner wall surface of the supply channel 6b. That is, when the supply flow path 6b moves from the manifold 5 (common flow path) side to the squeezing main body 6a side, the position of the center of gravity of the area of the cross section changes at the step 6d. Also in the flow path member 4 having such a configuration, a step (to be precise, the surface on the manifold 5 side in the portion where the first supply flow path 6b1 of FIG. 13 protrudes from the second supply flow path 6b2 and the surface of FIG. Adhesive is trapped at the surface of the main body 6a side of the second supply flow path 6b2 that protrudes from the first supply flow path 6b1, and the adhesive is trapped particularly at the end of the surface of the second supply flow path 6b2. Inflow of the agent can be prevented.

  In the actually produced flow path member 4, it is difficult to confirm that the position of the center of gravity of the area of the cross section changes with the step 6d as a boundary. Therefore, when confirming in the actual flow path member 4, one vertical cross section as shown in FIG. 14 is observed, and in the cross section, the center position of the flow path changes with the step 6d as a boundary. Check it.

DESCRIPTION OF SYMBOLS 1 ... Color inkjet printer 2 ... Liquid discharge head 2a ... Head main body 4 ... Flow path member 4a-4m ... (of flow path member) 4-1 ... Discharge hole surface 4 -2 ... Pressure chamber surface 5 ... Manifold (common flow path)
5a ... (manifold) opening 5b ... sub-manifold 6 ... squeezing 6a ... squeezing body 6b ... supply channel 6c ... discharge channel 6d ... step 6f ... recess 7 ... descender 8 ... Discharge hole 9 ... Discharge hole row 10 ... Pressure chamber 11 ... Pressure chamber row 12 ... Individual flow path 15 ... Partition wall 16 ... Dummy pressurization chamber 21. ..Piezoelectric actuator substrate 21a ... piezoelectric ceramic layer
21b ... Piezoelectric ceramic layer 24 ... Common electrode 25 ... Individual electrode 25a ... Individual electrode body 25b ... Extraction electrode 26 ... Connection electrode 28 ... Surface electrode for common electrode 30 ... -Displacement element 60 ... Signal transmission unit 70 ... Head mounting frame 72 ... Head group 80A ... Paper feed roller 80B ... Collection roller 82A ... Guide roller 82B ... Conveying roller 88 ..Control unit P: Printing paper

Claims (10)

A plurality of plates are laminated via an adhesive layer,
A plurality of discharge holes for discharging liquid;
A plurality of individual flow paths provided corresponding to each of the discharge holes, each connected to the corresponding discharge hole;
A common flow path in which a plurality of the individual flow paths are connected;
Have
Each of the individual flow paths is a pressure chamber provided in the middle of the path from the common flow path to the discharge hole in the individual flow path, and a squeezing connecting the pressure chamber and the common flow path. And
The squeezing is formed so as to extend in a direction along the plate, and the squeezing is formed so as to extend in the stacking direction of the plates, and connects the common flow path and the squeezing main body. A supply channel having a smaller channel resistance than the main body,
The supply flow path has a step on the inner wall surface of the supply flow path where the cross section of the supply flow path changes.
A flow path member for a liquid discharge head.   2. The liquid discharge head for a liquid ejection head according to claim 1, wherein the supply flow path has a smaller cross-sectional area with the step as a boundary when the supply flow path moves from the common flow path side to the narrowing body side. Channel member.   The flow path member for a liquid discharge head according to claim 2, wherein a recess is provided in the inner wall surface of the step facing the common flow path.   When the supply flow channel is viewed from the common flow channel side, the concave portion is provided so as to surround the flow channel on the side of the squeezing main body with a gap from the step. The flow path member for a liquid discharge head according to claim 3.   2. The liquid discharge head for a liquid ejection head according to claim 1, wherein the supply flow path has an area of the cross section that increases from the common flow path side toward the narrowing body side with the step as a boundary. Channel member.   6. The shape of the transverse section changes at the step as a boundary when the supply flow channel is directed from the common flow channel side to the narrowing body side. 6. A flow path member for a liquid discharge head as described.   The position of the center of gravity of the cross section of the cross section changes with the step as a boundary when the supply flow path is directed from the common flow path side to the narrowing body side. A flow path member for a liquid discharge head according to any one of the above.   The common flow path side of the step in the supply flow path is configured by a through hole provided in one of the plates, and the squeezing main body side of the supply flow path is the other plate. The flow path member for a liquid discharge head according to claim 1, wherein the flow path member is formed by a through hole provided in the liquid discharge head. A flow path member for a liquid discharge head according to any one of claims 1 to 8,
A plurality of pressurizing sections, each of which is provided corresponding to each of the pressurizing chambers, each applying pressure to the corresponding pressurizing chamber;
A liquid discharge head comprising:   A recording apparatus comprising: the liquid discharge head according to claim 9; a transport unit that transports a recording medium to the liquid discharge head; and a control unit that controls the liquid discharge head.

Images