JP5035486B2 - Liquid transfer device and inkjet head - Google Patents

Description

  The present invention relates to a liquid transfer apparatus and an ink jet head for transferring a liquid from a liquid inlet to a plurality of liquid outlets.

  An inkjet head that transports ink supplied from an ink tank and ejects ink droplets from a nozzle hole toward a recording sheet or the like is already known. This inkjet method is classified according to the difference in the generation method of the ejection energy, and the ink droplet is ejected by the generation of bubbles by the thermal energy and the piezoelectric method that ejects the ink droplet by using the vibration force of the piezoelectric element. There is a bubble jet (registered trademark) system. For example, a piezoelectric inkjet head disclosed in Japanese Patent Application Laid-Open No. 2004-25636 (Patent Document 1) corresponds to each nozzle in a flow path from a common liquid chamber connected to an ink supply port to a plurality of nozzle holes. A flow path unit provided with a plurality of pressure chambers and a piezoelectric actuator stacked on the flow path unit to selectively change the volume of the pressure chambers are provided. The piezoelectric actuator has a configuration in which a common electrode and a plurality of individual electrodes are alternately interposed between piezoelectric sheets in which a large number of sheets are laminated.

  According to the ink jet head, when a driving voltage is selectively applied to the individual electrodes of the piezoelectric actuator, an electric field acts on the active portion of the piezoelectric sheet sandwiched between the individual electrodes and the common electrode, and the thickness direction Deformation occurs. Then, the volume of the pressure chamber fluctuates due to the deformation of the piezoelectric sheet, and ink droplets are ejected from the nozzle holes by the pressure fluctuation generated in the ink in the pressure chamber. In addition, new ink is replenished from the common liquid chamber to the pressure chamber after ejection.

  The pressure wave acting on the pressure chamber has not only the forward component toward the nozzle hole but also the backward component toward the common liquid chamber. When the backward component of the pressure wave propagates to another adjacent pressure chamber via the common liquid chamber, a so-called crosstalk problem occurs. Therefore, the ink jet head has a damper wall for absorbing the backward component of the pressure wave. Is provided facing the common liquid chamber.

Japanese Patent Laid-Open No. 2004-25636

  However, due to recent improvements in ink jet technology, the density and size of ink jet heads have been further increased, and the area of the damper wall facing the common liquid chamber must be reduced accordingly. As described above, when the area of the damper wall facing the common liquid chamber becomes small, the vibration absorption performance of the damper wall becomes insufficient, and there arises a problem that the performance of preventing crosstalk is lowered.

  Accordingly, an object of the present invention is to provide a liquid transfer device and an ink jet head that can sufficiently ensure crosstalk prevention performance.

  The present invention has been made in view of the circumstances as described above, and the liquid transfer device according to the present invention corresponds to each of the plurality of liquid outlets in the flow path from the liquid inlet to the plurality of liquid outlets. A plurality of pressure chambers provided in at least two rows, and an actuator that applies a transfer pressure to the liquid in the pressure chambers, and the flow channel units communicate with the liquid inlets in the at least two rows. A common liquid chamber that supplies liquid to each pressure chamber, and a damper wall that elastically deforms facing the common liquid chamber, and the common liquid chamber and the damper wall are orthogonal to the wall surface of the damper wall. It is arranged so as to straddle the at least two rows of pressure chambers in a plan view as viewed from the direction, and the cross-sectional area of the flow path in the common liquid chamber is set at a position corresponding to the row of pressure chambers in the common liquid chamber. Forming a narrowed portion that narrows Cut walls are provided to project, and the common liquid chamber is provided with communication holes for supplying liquid to the pressure chamber on both sides straddling the partition wall, and the flow path unit includes: A pressure chamber layer having a pressure chamber hole constituting the pressure chamber; a manifold layer having a manifold hole constituting the common liquid chamber; and the pressure chamber layer and the manifold layer provided between the pressure chamber layer and the manifold layer. A connection channel layer constituting a connection channel that communicates with the liquid chamber, and a damper layer having the damper wall that is laminated on the opposite side of the manifold layer from the connection channel layer and faces the common liquid chamber; And the manifold layer is disposed adjacent to the connection flow path layer and has a plurality of divided manifold holes divided by the partition walls so as to individually communicate with each row of the pressure chambers. And a second manifold plate having a common manifold hole communicating with each of the divided manifold holes, and the height of the side surface of the first manifold plate along the plate thickness direction of the partition wall is the first manifold plate. It is the same as the thickness of the plate.

  In this way, the common liquid chambers that are conventionally divided and arranged corresponding to each row of pressure chambers are connected to one to supply liquid in common to at least two rows of pressure chambers. The chamber is enlarged so as to straddle at least two rows of pressure chambers in plan view. If it does so, the damper wall which faces a common liquid chamber can also be enlarged so that it may straddle at least 2 rows of pressure chambers by planar view. Therefore, the vibration absorption performance of the damper wall is sufficiently ensured, and the crosstalk prevention performance can be improved. In addition, the constriction part may block the backward component of the pressure wave generated from the pressure chamber of a certain row toward the common liquid chamber from propagating to the adjacent pressure chamber of another row through the common liquid chamber. It is possible to reduce crosstalk between columns. Furthermore, since the height of the side surface along the plate thickness direction of the partition wall of the first manifold plate is the same as the thickness of the first manifold plate, by the side surface along the plate thickness direction of the partition wall, Propagation of pressure waves to the adjacent pressure chambers in the adjacent row via the common liquid chamber can be suitably blocked by the side surface of the partition wall. The first manifold plate is formed with divided manifold holes whose positions corresponding to the rows of the pressure chambers are divided by the partition wall, and the second manifold plate is formed with a common manifold hole communicating with each of the divided manifold holes. In addition, since the narrowed portion is easily formed by the partition wall only by stacking the plates, the productivity of the liquid transfer device is improved.

  The height of the partition wall in the protruding direction may be greater than half the height of the common liquid chamber in the protruding direction. In this way, a narrowed portion with a small channel cross-sectional area is formed, and the effect of reducing crosstalk between rows can be enhanced.

  An end surface of the partition wall on the second manifold plate side may be flat.

  The thickness of the second manifold plate may be smaller than the thickness of the first manifold plate. In this way, the cross-sectional height of the narrowed portion becomes smaller than the thickness of the partition wall, and a narrowed portion having a smaller flow path cross-sectional area can be easily formed simply by changing the thickness of the plate.

  The damper layer may include the thin damper wall disposed at a position corresponding to the manifold hole, and a void portion located on the opposite side of the manifold layer with the damper wall as a boundary. In this manner, the elastically deformable damper wall can be easily formed by simply providing a gap on the opposite side of the damper wall facing the manifold hole in the flow path unit having a laminated structure.

  The pressure chamber communicates with the common liquid chamber via a connection channel at an end portion adjacent to the adjacent pressure chamber in the other row, and the liquid portion is disposed at an end portion on the side away from the other pressure chamber. The communication channel may be in communication with the outflow port, and the connection channel may have a throttle portion that provides the greatest channel resistance in the channel including the pressure chamber from the common liquid chamber. In this way, the backward component of the pressure wave generated in the pressure chamber toward the common liquid chamber is blocked by the throttle portion, and the energy of the pressure wave can be concentrated on the forward component toward the liquid outlet. In addition, since the portions communicating with the liquid outlets of the pressure chambers are respectively provided at the ends of the adjacent rows that are separated from each other, the influence of crosstalk between the rows can be reduced.

  The ink jet head of the present invention is an ink jet head that uses the liquid transfer device to eject a plurality of colors of ink, and the common liquid chamber is disposed so as to straddle two rows of the pressure chambers for at least one color. Further, the damper wall is provided, and the other liquid colors are provided with a common liquid chamber and a damper wall arranged corresponding to each row of the pressure chambers.

  In this way, for example, for light-colored inks such as yellow, where the influence of crosstalk is not conspicuous, the common liquid chamber and the damper wall are arranged corresponding to each row of pressure chambers as in the conventional case, while the influence of crosstalk is reduced. For dark ink, such as black, which is easily noticeable, it is possible to effectively improve the print quality with a simple structure by arranging the common liquid chamber and the damper wall so as to straddle two rows of pressure chambers.

  As is apparent from the above description, according to the present invention, the vibration absorption performance of the damper wall is sufficiently ensured, and the crosstalk prevention performance can be improved.

1 is an exploded perspective view showing an inkjet head according to a first embodiment of the present invention. It is a disassembled perspective view of the flow path unit of the inkjet head shown in FIG. It is a principal part enlarged view of the III-III line cross section of FIG. FIG. 2 is a plan view for explaining the positional relationship between a common liquid chamber and a damper wall with respect to a pressure chamber of the inkjet head shown in FIG. 1. It is principal part sectional drawing of the inkjet head of 2nd Embodiment. It is a principal part top view of the flow-path unit of the inkjet head of a reference form. It is the VII-VII sectional view taken on the line of FIG.

  Embodiments according to the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is an exploded perspective view showing a color inkjet head 1 according to a first embodiment of the present invention. As shown in FIG. 1, an inkjet head (liquid transfer device) 1 includes a flow path unit 2 in which a plurality of plates are stacked, and a piezoelectric actuator 3 that is bonded to the flow path unit 2 in an overlapping manner. It has. The flow path unit 2 is configured such that ink is ejected downward from nozzle holes 15a to 15c (see FIG. 3) opened on the lower surface side of the lowermost layer. A surface electrode 5 is formed on the upper surface of the actuator 3, and a flexible flat cable 4 for electrical connection with an external device is overlaid. A terminal (not shown) exposed on the lower surface of the flexible flat cable 4 is conductively connected to the surface electrode 5 of the actuator 3.

  FIG. 2 is an exploded perspective view of the flow path unit 2 of the inkjet head 1 shown in FIG. FIG. 3 is an enlarged view of a principal part taken along the line III-III in FIG. As shown in FIGS. 2 and 3, the flow path unit 2 includes a pressure chamber plate 8, a first connection flow path plate 9, a second connection flow path plate 10, a first manifold plate 11, and a second manifold. The plate 12, the damper plate 13, the cover plate 14, and the nozzle plate 15 are bonded and laminated. The nozzle plate 15 is a resin sheet such as polyimide, and the other plates 8 to 14 are metal plates such as a 42% nickel alloy steel plate (42 alloy), each having a thickness of about 50 to 150 μm. Each of the plates 8 to 15 is formed with an opening or a recess that constitutes a flow path by electrolytic etching, laser processing, plasma jet processing, or the like.

  As shown in FIG. 2, the pressure chamber plate 8 has five rows of pressure chamber holes 8 a to 8 e arranged along the long side, and ink supply holes (liquid inflow ports) 8 g to 8 j, It constitutes the chamber layer. The pressure chamber holes 8a to 8e have an oval shape having a long axis in a direction orthogonal to the row direction of the pressure chambers in plan view (see the pressure chambers 33, 36, and 40 in FIG. 4). The two rows of pressure chamber holes 8a and 8b and the ink supply holes 8g are for black ink, and the remaining three rows of pressure chamber holes 8c to 8e and ink supply holes 8h to 8j are inks of cyan, magenta, or yellow, respectively. Used for.

  As shown in FIGS. 2 and 3, the first connection flow path plate 9 includes communication holes 9a, 9c, and 9e that communicate with the end portions of the pressure chamber holes 8a to 8e, respectively, and the opposite sides of the pressure chambers 8a to 8e. Outflow through holes 9b, 9d, 9f communicating with the end portions, and ink supply holes 9g-9j communicating with the ink supply holes 8g-8j in the same shape are provided. (Note that the portions corresponding to the pressure chamber holes 8d and 8e in the left two rows in FIG. 2 are not shown.) The communication holes 9a and 9c communicating with the pressure chamber holes 8a and 8b for black ink are While the pressure chamber holes 8a and 8b are provided at the end portions close to each other, the outflow through holes 9b and 9d are provided at the end portions of the pressure chamber holes 8a and 8b on the side away from each other.

  The second connection flow path plate 10 has recesses 10a, 10d, 10g formed at one end in communication with the communication holes 9a, 9c, 9e along the major axis direction of the pressure chamber holes 8a-8e, and the recesses 10a, 10d. , 10g, the outflow through holes 10c, 10f, 10i communicating with the outflow through holes 9b, 9d, 9f, and the ink supply holes 9g-9j have the same shape. Ink supply holes 10i to 10l communicating with each other. The first connection flow path plate 9 and the second connection flow path plate 10 constitute a connection flow path layer.

  The first manifold plate 11 includes divided manifold holes 11a, 11c, 11e, 11h, and 11i extending in the row direction of the pressure chambers so as to communicate with the pressure chambers 8a to 8e via the communication holes 10b, 10e, and 10h, respectively. Outflow through holes 11b, 11d, and 11f communicated with the outflow through holes 10c, 10f, and 10i, respectively. A partition wall 11g is provided between the rows of the divided manifold holes 11a, 11c, 11e, 11h, and 11i. Then, one end of the pair of divided manifold holes 11a and 11c on the right side in FIG. 2 communicates with the ink supply hole 10i for black ink, and one end of the other divided manifold holes 11e, 11h and 11i is the other ink supply hole. 10j to 10l, respectively.

  The second manifold plate 12 has a common manifold hole 12a that communicates with both of the divided manifold holes 11a and 11c for black ink, and a divided manifold hole 12d that communicates with the other divided manifold holes 11e, 11h, and 11i in the same shape. 12f, 12g, and outflow through holes 12b, 12c, 12e communicating with the outflow through holes 11b, 11d, 11f, respectively. The first manifold plate 11 and the second manifold plate 12 constitute a manifold layer.

  The damper plate 13 is thinned by forming a recess from the opposite side to the common manifold hole 12a and forming a recess from the opposite side of the divided manifold holes 12d, 12f, and 12g. The damper walls 13e, 13h, and 13i and the outflow through holes 13c, 13d, and 13g communicating with the outflow through holes 12b, 12c, and 12e, respectively, constitute a damper layer. That is, as shown in FIG. 3, the damper layer has gaps 13b and 13f formed on the opposite sides of the manifold holes 12a and 12d with the damper walls 13a and 13e as boundaries.

  The cover plate 14 has outflow through holes 14a to 14c communicating with the outflow through holes 13c, 13d, and 13g, respectively. The nozzle plate 15 has nozzle holes (liquid outlets) 15a to 15c that communicate with the outflow through holes 14a to 14c, respectively, and eject ink to the outside. As shown in FIG. 2, the ink supply holes 8g to 8j of the pressure chamber plate 8 are covered with a filter 16 for removing dust mixed in ink supplied from an ink tank (not shown). Yes.

  Next, the ink flow path in the flow path unit 2 will be described with reference to FIGS. FIG. 4 is a plan view for explaining the positional relationship between the common liquid chamber and the damper wall with respect to the pressure chamber of the inkjet head 1 shown in FIG. (FIG. 4 is an enlarged view of two rows of pressure chambers 33 and 36 for black ink and one row of pressure chambers 40 for ink of other colors adjacent thereto.) First, for black ink, the common liquid chamber 30 extends in the row direction across two rows of pressure chambers 33 and 36 described later in plan view. That is, as shown in FIG. 3, the common liquid chamber 30 is hermetically sealed by the upper and lower sides of the divided manifold holes 11 a and 11 c and the common manifold hole 12 a being closed by the second connection flow path plate 10 and the damper plate 13. Is formed.

  In the common liquid chamber 30, a narrowed portion 30 a is formed in which the flow path cross-sectional area is narrowed by a partition wall 11 g located at a position corresponding to the row between the pressure chambers 33 and 36. The lower surface of the common liquid chamber 30 is formed by a damper wall 13a having substantially the same shape as the common liquid chamber 30 in plan view. The gap 13b located on the opposite side of the common liquid chamber 30 with the damper wall 13a as a boundary is hermetically sealed by closing the lower side to the cover plate 14.

  The common liquid chamber 30 communicates with the upper two rows of pressure chambers 33 and 36 via crank-like connecting flow paths 32 and 35 on both sides of the partition wall 11g. The connection channels 32 and 35 are formed by the communication holes 9a and 9c of the first connection channel plate 9, the recesses 10a and 10d of the second connection channel plate 10, and the communication holes 10b and 10e. The connection channels 32 and 35 have throttle portions 32a and 35a that have the largest channel resistance with the narrowest channel cross-sectional area among the channels from the common liquid chamber 30 to the pressure chambers 33 and 36.

  The pressure chambers 33 and 36 are formed by closing the upper and lower sides of the pressure chamber holes 8 a to 8 e with the actuator 3 and the first connection flow path plate 9. The connection channels 32 and 35 communicate with the end portions on the side close to the two rows of pressure chambers 33 and 36. The end portions of the two rows of pressure chambers 33 and 36 that are separated from each other are arranged so as to protrude slightly outside the common liquid chamber 30 in plan view, and the outflow passages 34 and 37 communicate with the end portions. Yes. These outflow passages 34, 37 are formed by outflow through holes 9b, 10c, 11b, 12b, 13c, 14a and 9d, 10f, 11d, 12c, 13d, 14b, and are formed in the lower nozzle holes 15a, 15b. The shape gradually decreases in diameter toward the stacking direction (in a direction perpendicular to the plate surface). As described above, the outflow passages 34 and 37 are vertically suspended, so that the irregular reflection of pressure on the inner surfaces of the outflow passages 34 and 37 is reduced.

  Next, since the three rows of flow paths for cyan, magenta, and yellow inks are the same as each other, one row of the flow passages will be described as a representative. As shown in FIGS. 3 and 4, the common liquid chamber 38 extends in the row direction below a row corresponding to a row of pressure chambers 40 described later. The lower surface of the common liquid chamber 38 is formed by a damper wall 13e having substantially the same shape as the common liquid chamber 38 in plan view. The common liquid chamber 38 communicates with the upper row of pressure chambers 40 via a crank-shaped connection channel 39.

  The pressure chamber 40 has the same shape as the pressure chambers 33 and 36 for black ink, and a connection channel 39 communicates with an end portion on the side away from the pressure chamber 36 for black ink. An outflow path 41 serving as an outflow path communicates with the end of the pressure chamber 40 on the side close to the pressure chamber 33 for black ink. The outflow passage 41 is provided so as to be gradually reduced in diameter toward the lower nozzle hole 15c and is vertically provided in the stacking direction (direction perpendicular to the plate surface).

  Next, as shown in FIG. 3, the actuator 3 has a large number of piezoelectric sheets 20 to 25 made of a ceramic material of lead zirconate titanate (PZT) having a thickness of about 30 μm, and an insulating property. The top sheet 26 is stacked. Commonly arranged on the upper surface of the odd-numbered piezoelectric sheets 20, 22, 24 counting upward from the lowermost piezoelectric sheet 20 among the piezoelectric sheets 20, corresponding to a number of pressure chambers 33, 36, 40. An electrode 27 is formed by printing. On the upper surface of the even-numbered piezoelectric sheets 21 and 23 counted upward from the lowermost piezoelectric sheet 20, a large number of individual electrodes 28 arranged to correspond to the respective pressure chambers 33, 36, and 40 are arranged in five rows. Print formed. Further, the common electrode 27 and the individual electrode 28 are connected to the top sheet 26 of the uppermost layer via relay wiring (not shown) provided on the side end surfaces of the piezoelectric sheets 20 to 25 and the top sheet 26 or through holes (not shown). Is electrically connected to the surface electrode 5 (see FIG. 1) on the upper surface of the substrate.

  Next, the operation of the inkjet head 1 will be described. As shown in FIG. 3, a voltage is selectively applied to the individual electrode 28 of the actuator 3 and a potential difference is generated between the individual electrode 28 and the common electrode 27, so that it is positioned between the electrodes 27 and 28 of the piezoelectric sheets 21 to 24. An electric field acts on the active portion to cause strain deformation in the stacking direction. For example, when pressure is applied to the ink in the right pressure chamber 33 due to the deformation of the active portion, the ink is ejected from the nozzle hole 15 a through the outflow path 34. At that time, the pressure wave acting on the pressure chamber 33 has not only the forward component toward the nozzle 15 a but also the backward component toward the common liquid chamber 30. The backward component of the pressure wave is blocked to some extent by the throttle portion 32 a, but part of it propagates to the common liquid chamber 30. The backward component of the pressure wave propagated to the common liquid chamber 30 is absorbed by elastic deformation of the thin damper wall 13a. As a result, the so-called crosstalk in which the backward component of the pressure wave generated in the pressure chamber 33 propagates to the other adjacent pressure chambers 33 and 36 via the common liquid chamber 30 is prevented.

  Furthermore, since the common liquid chamber 30 and the damper wall 13a are arranged in a large area so as to straddle the two rows of pressure chambers 33 and 36 in a plan view, the vibration of the damper wall 13a is increased even if the density of the inkjet head 1 is increased. Absorption performance is sufficiently ensured and crosstalk prevention performance is improved (damper performance is proportional to the fifth power of the width of the damper wall 13a). Further, since the constricted portion 30a for narrowing the cross-sectional area of the flow path is provided at a position corresponding to the space between the pressure chambers 33 and 36 in the common liquid chamber 30, it is generated from the pressure chamber 33 toward the common liquid chamber 30 The receding component of the pressure wave is prevented from propagating to the adjacent pressure chambers 36 in other rows, and crosstalk between rows is effectively prevented.

  Further, in the inkjet head 1, for the black ink that is easily affected by the crosstalk, the common liquid chamber 30 and the damper wall 13a are disposed so as to straddle the two rows of the pressure chambers 33 and 36. For other inks such as yellow that are not noticeable, the common liquid chamber 38 and the damper wall 13e are arranged corresponding to each row of the pressure chambers 40, and the print quality can be effectively improved with a simple structure. It becomes possible.

(Second Embodiment)
FIG. 5 is a cross-sectional view of a main part of the inkjet head 100 according to the second embodiment. The difference from the first embodiment is that the thickness of the second manifold plate 51 is changed. In addition, about the part which is common in 1st Embodiment, the same code | symbol is attached | subjected and the following description is abbreviate | omitted. As shown in FIG. 5, in the flow path unit 50 of the inkjet head 100 of the present embodiment, the thickness T <b> 2 of the second manifold plate 51 is smaller than the thickness T <b> 1 of the first manifold plate 11. Specifically, the value of T2 / T1 is preferably set in the range of 0.2 to 0.7.

  The second manifold plate 51 has a common manifold hole 51a that communicates with each of the divided manifold holes 11a and 11c of the first manifold plate 11, a divided manifold hole 51d that communicates with each other in the same shape as the other divided manifold holes 11e, and an outflow. Outflow through holes 51b, 51c, 51e communicating with the through holes 11b, 11d, 11f, respectively. The first manifold plate 11 and the second manifold plate 51 constitute a manifold layer. In the common liquid chamber 52, the upper and lower sides of the divided manifold holes 11 a and 11 c of the first manifold plate 11 and the common manifold hole 51 a of the second manifold plate 51 are closed by the second connection flow path plate 10 and the damper plate 13. It is formed with.

  According to the inkjet head 100 having the above configuration, since the thickness T2 of the second manifold plate 51 is smaller than the thickness T1 of the first manifold plate 11, the sectional height of the constricted portion 52a of the common liquid chamber 52 is equal to the partition wall. It becomes smaller than the thickness of 11 g. Therefore, it is possible to easily form the narrowed portion 52a having a smaller flow path cross-sectional area by appropriately changing the thickness T2 of the second manifold plate 52.

(Reference form)
FIG. 6 is a plan view of an essential part of the flow path unit 200 of the inkjet head according to the reference embodiment. 7 is a sectional view taken along line VII-VII in FIG. In addition, about the part which is common in 1st Embodiment, the same code | symbol is attached | subjected and the following description is abbreviate | omitted.

  As shown in FIG. 7, the flow path unit 200 includes a pressure chamber plate 8, a connection flow path plate 210, a first manifold plate 220, a second manifold plate 12, a damper plate 13, a cover plate 14, The nozzle plate 15 is laminated and bonded. That is, in this embodiment, the connection flow path 232 described later is formed by a single plate 210.

  The connection flow path plate 210 communicates with one end portion of the pressure chamber hole 8a of the pressure chamber plate 8, and is formed at a recess portion 210a extending along the major axis direction of the pressure chamber hole 8a and at the other end portion of the recess portion 210a. And the outflow through hole 210d communicating with the other end of the pressure chamber 8a.

  The first manifold plate 220 has a common manifold hole 220a having the same shape as the common manifold hole 12a of the second manifold plate 12, and an outflow through hole 220b communicating with the outflow through hole 210d. The holes 220 a extend in the row direction of the pressure chambers so as to communicate with the communication holes 210 b of the connection flow path plate 210.

  A common liquid chamber 230 is formed by closing the upper and lower sides of the common manifold holes 220a, 12a of the first and second manifold plates 220, 12 with the connection flow path plate 210 and the damper plate 13. The common liquid chamber 230 extends in the row direction across the two rows of pressure chambers 33 and 36 in plan view.

  Further, the recess 210 a of the connection channel plate 210 is closed from above by the pressure chamber plate 8, whereby the connection channel 232 is formed. As shown in FIG. 6, the connection flow path 232 is connected from the pressure chamber 33 (or 36) to which the connection channel 232 communicates to two adjacent pressure chambers 36 and 36 (or 33 and 33) in the adjacent row in a plan view. It is extended. The connection flow path 232 has a throttle portion that has the largest flow path resistance with the narrowest cross-sectional area among the flow paths from the common liquid chamber 230 to the pressure chamber 33.

  Further, as shown in FIG. 7, the pressure chamber hole 8 a of the pressure chamber plate 8 is closed from below by the connection flow path plate 210, thereby forming the pressure chamber 33. The connection channel 232 communicates with the pressure chamber 33 by the end portion 210c of the recess 210a overlapping the pressure chamber hole 8a in plan view.

  According to the above configuration, since one plate 210 for forming the connection flow path 232 is sufficient, the number of parts and cost can be reduced. Further, since the number of plates to be used is reduced, it is possible to reduce the positional deviation at the time of stacking assembly, and it is possible to improve the yield.

  In addition, although each embodiment mentioned above applies this invention to an inkjet head, you may apply to the liquid transfer apparatus which transfers liquids other than an ink. In addition, the pressure chambers of the respective embodiments described above have the same shape and the same size, but the injection amounts may be changed by making the sizes of the two pressure chambers 33 and 36 different.

  As described above, the liquid transfer device and the ink jet head according to the present invention have an excellent effect of suitably preventing crosstalk, and are beneficial when applied to an ink jet printer or the like.

1 Inkjet head (liquid transfer device)
2, 50, 200 Channel unit 3 Actuator 8a, 8b Pressure chamber hole 8g Ink supply port (liquid inlet)
11, 220 First manifold plates 11a, 11c Divided manifold holes 11g Partition walls 12, 51 Second manifold plates 12a, 51a Common manifold holes 13a, 13e Damper walls 13b, 13f Gaps 15a, 15b Nozzle holes (liquid outlets)
30, 38, 52 Common liquid chambers 30a, 52a Narrowed portions 32, 35, 232 Connection flow paths 33, 36, 40 Pressure chambers

Claims (7)

A flow path unit in which a plurality of pressure chambers respectively corresponding to the plurality of liquid outlets are provided in a flow path from the liquid inlet to the plurality of liquid outlets, and a transfer pressure to the liquid in the pressure chamber An actuator for feeding,
The flow path unit includes a common liquid chamber that communicates with the liquid inlet and supplies liquid to the pressure chambers in the at least two rows, and a damper wall that elastically deforms facing the common liquid chamber,
The common liquid chamber and the damper wall are disposed so as to straddle the at least two rows of pressure chambers in a plan view as viewed from a direction orthogonal to the wall surface of the damper wall;
A partition wall forming a constricted portion for narrowing a cross-sectional area of the flow path in the common liquid chamber is provided to project at a position corresponding to the space between the pressure chambers in the common liquid chamber,
The common liquid chamber is provided with communication holes for supplying liquid to the pressure chamber on both sides straddling the partition wall,
The flow path unit is provided between a pressure chamber layer having a pressure chamber hole constituting the pressure chamber, a manifold layer having a manifold hole constituting the common liquid chamber, and the pressure chamber layer and the manifold layer. A connection flow path layer constituting a connection flow path for communicating the pressure chamber and the common liquid chamber, and the damper which is laminated on the opposite side of the manifold layer from the connection flow path layer and faces the common liquid chamber A damper layer having a wall,
The manifold layer is disposed adjacent to the connection flow path layer and has a first manifold plate having a plurality of divided manifold holes divided by the partition walls so as to communicate individually with each row of the pressure chambers, and the divided A second manifold plate having a common manifold hole communicating with each of the manifold holes,
The liquid transfer device according to claim 1, wherein a height of a side surface of the first manifold plate along the plate thickness direction of the partition wall is the same as a thickness of the first manifold plate.   The liquid transfer device according to claim 1, wherein a height of the partition wall in the protruding direction is greater than half of a height of the common liquid chamber in the protruding direction.   The liquid transfer device according to claim 1, wherein an end surface of the partition wall on the second manifold plate side is flat.   4. The liquid transfer device according to claim 1, wherein a thickness of the second manifold plate is smaller than a thickness of the first manifold plate. 5.   5. The damper layer according to claim 1, wherein the damper layer includes the thin damper wall disposed at a position corresponding to the manifold hole, and a void portion located on the opposite side of the manifold layer with the damper wall as a boundary. A liquid transfer apparatus according to claim 1. The pressure chamber communicates with the common liquid chamber via a connection channel at an end portion adjacent to the adjacent pressure chamber in the other row, and the liquid portion is disposed at an end portion on the side away from the other pressure chamber. Communicating with the outlet,
The liquid transfer device according to any one of claims 1 to 5, wherein the connection flow path has a throttle portion that provides the largest flow path resistance in the flow path including the pressure chamber from the common liquid chamber. An ink jet head that uses the liquid transfer device according to claim 1 to eject a plurality of colors of ink.
At least one color is provided with the common liquid chamber and the damper wall arranged so as to straddle two rows of the pressure chambers, and other colors are arranged corresponding to each row of the pressure chambers. An ink jet head comprising a common liquid chamber and a damper wall.

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