JP2010023385A - Liquid transferring apparatus - Google Patents

Abstract

A pressure wave generated in a pressure chamber is prevented from propagating to another pressure chamber.
A pressure chamber is connected to a manifold channel through a connection channel formed by a through hole, a throttle channel, a pressure wave attenuation space, and a through hole. The throttle channel 13 extends in the scanning direction from the through hole 12 communicating with the pressure chamber 10 toward the nozzle 17. By having a substantially elliptical planar shape with the scanning direction as the longitudinal direction, the cross-sectional area in the direction orthogonal to the channel axis direction is larger than the other portions of the connection channel. In addition, the throttle channel 13 and the pressure wave attenuation space 14 are connected at their ends opposite to the through-hole 12 in the scanning direction, which is the extending direction, so that the connection channel is the throttle channel 13. And the pressure wave attenuating space 14 are bent.
[Selection] Figure 3

Description

  The present invention relates to a liquid transfer apparatus for transferring a liquid.

  The droplet ejecting device described in Patent Document 1 includes a flow path unit in which an ink flow path is formed from a manifold flow path (common liquid chamber) through a pressure chamber to a nozzle, and a piezoelectric device that applies pressure to ink in the pressure chamber. When a pressure is applied to the ink in the pressure chamber by the piezoelectric actuator, the ink is ejected from a nozzle communicating with the pressure chamber.

JP 2008-80724 A

  Here, in the droplet ejecting apparatus described in Patent Document 1, a pressure wave is generated when pressure is applied to the ink in the pressure chamber, and this pressure wave propagates to the manifold channel. When the manifold flow path is made smaller for miniaturization, etc., the pressure wave is not sufficiently attenuated in the manifold flow path and propagates to other pressure chambers, and from the nozzle communicating with the other pressure chambers. Ink ejection characteristics (liquid transfer characteristics) may vary.

  An object of the present invention is to provide a liquid transfer device capable of preventing the liquid transfer characteristics from fluctuating due to pressure waves.

  The liquid transfer device according to the first invention includes a plurality of pressure chambers, a common liquid chamber for supplying a liquid to the plurality of pressure chambers, and a plurality of connections for connecting the plurality of pressure chambers and the common liquid chamber, respectively. A flow path unit formed by laminating a plurality of plates including a plate provided with a hole that can serve as a flow path and the chamber, and a pressure applied to the liquid in the pressure chamber. A pressure applying means for applying, wherein each of the plurality of connection flow paths is provided in the middle of the plurality of connection flow paths, and a direction perpendicular to the flow path axial direction than other portions of the plurality of connection flow paths. A pressure wave attenuation space for attenuating a pressure wave propagating in the connection channel, a pressure chamber side channel connecting the pressure wave attenuation space and the pressure chamber, Common with pressure wave attenuation space And it is characterized in that it is composed of a common liquid chamber side flow passage that connects the chamber.

  According to this, since the pressure wave attenuation space having a larger cross-sectional area in the direction orthogonal to the channel axial direction than the other part of the connection channel is provided in the middle of the connection channel, the connection channel The pressure wave propagating through the pressure wave is attenuated by the pressure wave attenuation space, propagates to the common liquid chamber, and is further attenuated in the common liquid chamber. This prevents the pressure wave from propagating to other pressure chambers via the common liquid chamber.

  A liquid transfer device according to a second invention is the liquid transfer device according to the first invention, wherein the plurality of plates are formed with a pressure chamber plate in which the plurality of pressure chambers are formed and the common liquid chamber. A common liquid chamber plate, and two or more plates stacked between the pressure chamber plate and the common liquid chamber plate, and the plurality of connection flow paths are formed in the two or more plates. It is characterized by being.

  According to this, two or more plates arranged between the pressure chamber plate and the common liquid chamber plate are formed with holes or the like serving as connection flow paths including the pressure wave attenuation space, and these two or more plates are mounted. By laminating the pressure chamber plate and the common liquid chamber plate, the connection flow path including the pressure wave attenuation space can be easily formed on these two or more plates.

  A liquid transfer device according to a third invention is the liquid transfer device according to the second invention, wherein the plurality of connection flow paths are the plurality of pressure chambers and the common liquid as viewed from the stacking direction of the plurality of plates. It is arrange | positioned in the part which overlaps at least any one of the chambers, It is characterized by the above-mentioned.

  According to this, since the connection flow path is disposed in a portion overlapping at least one of the pressure chamber and the common liquid chamber when viewed from the stacking direction of the plurality of plates, the plate is formed to form the connection flow path. There is no need to increase the size, and as a result, the liquid transfer device does not increase in size.

  A liquid transfer device according to a fourth aspect of the invention is the liquid transfer device according to the second or third aspect of the invention, wherein the plurality of connection flow paths are at a connection portion between the pressure wave attenuation space and the pressure chamber side flow path. It is characterized by being bent.

  According to this, the pressure wave propagating through the connection channel from the pressure chamber side toward the pressure wave attenuation space is reflected at the connection portion between the pressure chamber side channel and the pressure wave attenuation space, and the entire area of the pressure wave attenuation space is reflected. Propagate to spread. As a result, the pressure wave is efficiently attenuated in the pressure wave attenuation space.

  A liquid transfer device according to a fifth aspect of the invention is the liquid transfer device according to the fourth aspect of the invention, wherein the pressure wave attenuation space and a portion in the vicinity of a connection portion with at least the pressure wave attenuation space in the pressure chamber side flow path. Are both extended in a predetermined direction parallel to the surface direction of the plurality of plates, and the predetermined portion of the pressure wave attenuation space and the portion extending in the predetermined direction of the pressure chamber side flow path The ends on the same side in one direction are connected to each other.

  According to this, both of the connection flow path, the pressure wave attenuation space, and at least the portion near the connection portion of the pressure chamber side flow path with the pressure wave attenuation space extend in a predetermined direction, and the pressure wave attenuation. By connecting the end portions on the same side in the predetermined direction of the space and the portion extending in the predetermined direction of the pressure chamber side flow path, the connection flow path is connected to the pressure chamber side flow. The pressure wave propagating from the pressure chamber side toward the pressure wave attenuation space is connected to the pressure chamber side flow path and the pressure wave attenuation space. Reflected at the connecting portion and propagated throughout the pressure wave attenuation space. As a result, the pressure wave is efficiently attenuated in the pressure wave attenuation space.

  In addition, since the propagation direction of the pressure wave propagating through the part extending in one predetermined direction of the pressure chamber side flow path and the propagation direction of the pressure wave propagating in the pressure wave attenuation space are almost opposite directions, The wave is reliably reflected at the connecting portion between the pressure chamber side flow path and the pressure wave attenuation space, and spreads over the entire pressure wave attenuation space.

  The liquid transfer device according to a sixth aspect of the invention is the liquid transfer device according to the second to fifth aspects of the invention, wherein the pressure chamber side flow channel is branched in the middle thereof, and the pressure chamber side flow channel is branched. The portions are respectively connected to different portions of the pressure wave attenuation space.

  According to this, the pressure wave propagating from the pressure chamber side flow path toward the pressure wave attenuation space propagates from the branched part of the pressure chamber side flow path to different parts of the pressure wave attenuation space, so the pressure wave It spreads throughout the pressure wave attenuation space and is attenuated efficiently.

  A liquid transfer device according to a seventh invention is the liquid transfer device according to the second to sixth inventions, wherein the pressure wave attenuation space is a plate joined to the common liquid chamber plate among the two or more plates. The pressure chamber side surface is formed by a recess formed in a portion overlapping with the common liquid chamber when viewed from the stacking direction of the plurality of plates.

  According to this, the concave portion of the plate laminated on the pressure chamber plate side surface of the common liquid chamber plate is formed, and the portion where the thickness is reduced becomes the wall of the common liquid chamber, and the portion that becomes the wall of this common liquid chamber Due to the deformation, the pressure wave is efficiently attenuated even in the common liquid chamber.

  According to an eighth aspect of the present invention, there is provided a liquid transfer device comprising: a plurality of pressure chambers; a common liquid chamber that supplies liquid to the plurality of pressure chambers; and a plurality of connections that connect the plurality of pressure chambers and the common liquid chamber, respectively. A flow path unit having a flow path, and a pressure applying means for applying pressure to the liquid in the pressure chamber, each of the plurality of connection flow paths being provided in the middle thereof, A pressure wave attenuating space for attenuating a pressure wave propagating in the connecting channel, wherein a cross-sectional area in a direction orthogonal to the channel axis direction is larger than other portions in the connecting channel, and the pressure wave The pressure wave attenuation space is composed of a pressure chamber side flow path connecting the attenuation space and the pressure chamber, and a common liquid chamber side flow path connecting the pressure wave attenuation space and the common liquid chamber. At the connection between the pressure chamber side flow path And it is characterized in that the bent.

  According to this, since the pressure wave attenuation space having a larger cross-sectional area in the direction orthogonal to the channel axial direction than the other part of the connection channel is provided in the middle of the connection channel, the connection channel The pressure wave propagating through the pressure wave is attenuated by the pressure wave attenuation space, propagates to the common liquid chamber, and is further attenuated in the common liquid chamber. This prevents the pressure wave from propagating to other pressure chambers via the common liquid chamber.

  Furthermore, at this time, the pressure wave propagating from the pressure chamber side toward the pressure wave attenuation space through the connection channel is reflected at the connection portion between the pressure chamber side channel and the pressure wave attenuation space, and the pressure wave attenuation space Since the propagation propagates over the entire area, the pressure wave is efficiently attenuated in the pressure wave attenuation space.

  A liquid transfer device according to a ninth invention is the liquid transfer device according to the eighth invention, wherein the pressure wave attenuation space and at least a portion in the vicinity of a connection portion with the pressure wave attenuation space in the pressure chamber side flow path. Are both extended in a predetermined direction parallel to the surface direction of the plurality of plates, and the predetermined portion of the pressure wave attenuation space and the portion extending in the predetermined direction of the pressure chamber side flow path The ends on the same side in one direction are connected to each other.

  According to this, both of the connection flow path, the pressure wave attenuation space, and at least the portion near the connection portion of the pressure chamber side flow path with the pressure wave attenuation space extend in a predetermined direction, and the pressure wave attenuation. By connecting the end portions on the same side in the predetermined direction of the space and the portion extending in the predetermined direction of the pressure chamber side flow path, the connection flow path is connected to the pressure chamber side flow. The pressure wave propagating from the pressure chamber side toward the pressure wave attenuation space is connected to the pressure chamber side flow path and the pressure wave attenuation space. Reflected at the connecting portion and propagated throughout the pressure wave attenuation space. As a result, the pressure wave is efficiently attenuated in the pressure wave attenuation space.

  In addition, since the propagation direction of the pressure wave propagating through the part extending in one predetermined direction of the pressure chamber side flow path and the propagation direction of the pressure wave propagating in the pressure wave attenuation space are almost opposite directions, The wave is reliably reflected at the connecting portion between the pressure chamber side flow path and the pressure wave attenuation space, and spreads over the entire pressure wave attenuation space.

  According to the present invention, the pressure wave attenuation space having a larger cross-sectional area in the direction orthogonal to the channel axial direction than the other part of the connection channel is provided in the middle of the connection channel. The pressure wave propagating through the flow path is attenuated by the pressure wave attenuation space, and the pressure wave is prevented from propagating to other pressure chambers via the common liquid chamber.

  Further, according to the present invention, the pressure wave propagating from the pressure chamber side toward the pressure wave attenuation space through the connection flow path is reflected at the connection portion between the pressure chamber side flow path and the pressure wave attenuation space, and the pressure wave is reflected. Propagates so as to spread over the entire attenuation space. As a result, the pressure wave is efficiently attenuated in the pressure wave attenuation space.

  Hereinafter, preferred embodiments of the present invention will be described.

  FIG. 1 is a schematic configuration diagram of a printer according to the present embodiment. As shown in FIG. 1, the printer 1 includes a carriage 2, an ink jet head 3 (liquid transport device), a transport roller 4, and the like.

  The carriage 2 reciprocates in the scanning direction (left and right direction in FIG. 1). The inkjet head 3 is attached to the lower surface of the carriage 2 and ejects ink from nozzles 17 (see FIG. 2) formed on the lower surface. The transport roller 4 transports the recording paper P in the paper feed direction (front side in FIG. 1). In the printer 1, printing is performed on the recording paper P by ejecting ink onto the recording paper P from the nozzles 17 of the inkjet head 3 that reciprocally move in the scanning direction together with the carriage 2. Further, the recording paper P for which printing has been completed is discharged in the paper feeding direction by the transport roller 4.

  Next, the inkjet head 3 will be described in detail. FIG. 2 is a plan view of the inkjet head 3 of FIG. FIG. 3 is a partially enlarged view of FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. As shown in FIGS. 2 to 4, the inkjet head 3 includes a flow path unit 31 in which an ink flow path such as a pressure chamber 10 described later is formed, and a piezoelectric actuator 32 (which applies pressure to ink in the pressure chamber 10). Pressure applying means).

  The flow path unit 31 includes a cavity plate 21 (pressure chamber plate), an aperture plate 22, a base plate 23, two manifold plates 24 and 25 (common liquid chamber plate), a damper plate 26, a supply plate 27, and a nozzle plate 28. It is configured by being laminated. Of the eight plates 21 to 28, the seven plates 21 to 27 except for the nozzle plate 28 are made of a metal material such as stainless steel, and the nozzle plate 28 is made of a synthetic resin material such as polyimide. It is configured. Or the nozzle plate 28 may be comprised with the metal material like the other plates 21-27.

  The cavity plate 21 is formed with through holes that serve as a plurality of pressure chambers 10. The pressure chamber 10 has a substantially elliptical planar shape whose longitudinal direction is the scanning direction (left-right direction in FIG. 4). The plurality of pressure chambers 10 are arranged in the paper feeding direction (vertical direction in FIG. 4) to form a pressure chamber row, and such pressure chamber rows are arranged in two rows in the scanning direction. ing.

  The aperture plate 22 is formed with a through-hole 12, and a concave portion serving as a throttle channel 13 and a pressure wave attenuation space 14 is formed on the lower surface thereof. The through hole 12 is formed in a portion that overlaps one end portion in the longitudinal direction of the pressure chamber 10 in plan view. In the plan view, the throttle channel 13 has a portion that overlaps with a substantially central portion in the paper feeding direction of the pressure chamber 10 slightly opposite to the through hole 12 from the through hole 12 to a substantially central portion in the longitudinal direction of the pressure chamber 10. It extends in the scanning direction (predetermined one direction) to the portion that overlaps the portion.

  Since the through hole 12 and the throttle channel 13 have such shapes, the cross-sectional area in the direction orthogonal to the vertical direction (channel axis direction) of the through hole 12 and the scanning of the throttle channel 13 are obtained. The cross-sectional area in the direction orthogonal to the direction (flow path axis direction) is smaller than the cross-sectional area in the direction orthogonal to the scanning direction (flow path axis direction) of the pressure chamber 10. Here, the channel axis direction is the direction in which the main flow of ink flows in the channel. The through hole 12 and the throttle channel 13 correspond to the pressure chamber side channel according to the present invention.

  The pressure wave attenuation space 14 is arranged so as to be adjacent to the upper side of the throttle channel 13 in FIG. The pressure wave attenuation space 14 has a substantially elliptical planar shape whose length in the scanning direction is shorter than that of the pressure chamber 10 and whose longitudinal direction is the scanning direction (extending in the scanning direction (predetermined one direction)). . Since the pressure wave attenuating space 14 has such a shape, the cross-sectional area in the direction orthogonal to the scanning direction (flow channel axial direction) of the pressure wave attenuating space 14 is the flow of the through hole 12 and the throttle channel 13. It is larger than the cross-sectional area in the direction orthogonal to the road axis direction.

  Further, the end of the throttle channel 13 extending in the scanning direction (the portion in the vicinity of the connecting portion of the pressure chamber side channel with at least the pressure wave attenuation space 14) on the side opposite to the through-hole 12 and the scanning direction 3 that is opposite to the through hole 12 in the scanning direction of the pressure wave attenuation space 14 extending in the direction (the end on the same side in the predetermined direction of the throttle channel 13 and the pressure wave attenuation space 14). Are connected to each other.

  In the present embodiment, the aperture plate 22 is formed with the through hole 12, the throttle channel 13, and the pressure wave attenuation space 14, but is orthogonal to the channel axial directions of the through hole 12 and the throttle channel 13. Since the cross-sectional area with respect to the direction is relatively small, the aperture plate 22 has a sufficient space for forming the pressure wave attenuation space 14 with a relatively large cross-sectional area with respect to the direction orthogonal to the flow path axis direction.

  In the base plate 23, a through hole 15 (common liquid chamber side flow path) is formed in a portion overlapping the upper right end portion in FIG. 2 of the pressure wave attenuation space 14 in a plan view. The cross-sectional area in the direction orthogonal to the (path axis direction) is smaller than the cross-sectional area in the direction orthogonal to the scanning direction (flow path axis direction) of the pressure wave attenuation space 14. In the present embodiment, the flow path including the through hole 12, the throttle flow path 13, the pressure wave attenuation space 14, and the through hole 15 corresponds to the connection flow path according to the present invention.

  In other words, the connection flow path has a cross-sectional area in the pressure wave attenuation space 14 that is larger in the direction perpendicular to the flow path axis direction than in other portions. Further, in this connection channel, the throttle channel 13 and the pressure wave attenuation space 14 are arranged as described above, so that the connection portion between the throttle channel 13 and the pressure wave attenuation space is bent.

  The manifold plates 24 and 25 have through holes 24a and 25a, respectively, and the manifold channel 11 is formed by overlapping the through holes 24a and the through holes 25a. The manifold channel 11 excludes the portion excluding the left end portion of the pressure chamber 10 constituting the right pressure chamber row in FIG. 2 and the right end portion of the pressure chamber 10 constituting the left pressure chamber row in FIG. It extends in two rows in the paper feed direction along the aforementioned pressure chamber row so as to overlap each portion. Further, the manifold channel 11 is connected to each other at the lower end portion in FIG. Ink is supplied to the manifold channel 11 from an ink supply channel 9 formed in a portion overlapping the lower end portion of the manifold channel 11 in plan view.

  Here, the through hole 12, the throttle channel 13, the pressure wave attenuation space 14 and the through hole 15, which are connection channels according to the present invention for connecting the pressure chamber 10 and the manifold channel 11, are all connected to the cavity plate 21. In the plates 22 and 23 (two or more plates) disposed between the manifold plate 24 and the manifold plate 24, they are disposed in portions overlapping the manifold flow path 11 and the pressure chamber 10 in plan view. Thereby, the flow path unit 31 (inkjet head 3) is not enlarged in the surface direction by the through hole 12, the throttle flow path 13, the pressure wave attenuation space 14, and the through hole 15 (forms a connection flow path). Therefore, it is not necessary to enlarge the plate), and as a result, the inkjet head 3 is not enlarged.

  In addition, the plates 22 and 23 are formed with through-holes and recesses that become the through-holes 12, the throttle channel 13, the pressure wave attenuation space 14 and the through-holes 15, and the plates 22 and 23 are connected to the cavity plate 21 and the manifold plate 24. By laminating, it is possible to easily form the connection flow paths (through hole 12, throttle flow path 13, pressure wave attenuation space 14 and through hole 15) in the plates 22 and 23.

  A recess 18 is formed in the damper plate 26 at a portion overlapping the manifold channel 11 in plan view on the lower surface thereof. As a result, the damper plate 26 has a reduced thickness at a portion overlapping the manifold channel 11 in a plan view, and a portion of the damper plate 26 having the reduced thickness is deformed, thereby attenuating a pressure wave described later.

  The supply plate 27 closes the opening of the recess 18 formed in the damper plate 26. Further, in the aperture plate 22, the base plate 23, the manifold plates 24 and 25, the damper plate 26, and the supply plate 27, the portions that overlap with the end on the opposite side to the through hole 12 in the longitudinal direction of the pressure chamber 10 are respectively A through hole forming the descender flow path 16 is formed. A nozzle 17 is formed in the nozzle plate 28 at a portion overlapping the descender flow path 16 in plan view.

  In the flow path unit 31, the manifold flow path 11 communicates with the pressure chamber 10 via the through hole 15, the pressure wave attenuation space 14, the throttle flow path 13, and the through hole 12. The nozzle 17 communicates with the passage 16. As described above, the flow path unit 31 is formed with a plurality of individual ink flow paths from the outlet of the manifold flow path 11 to the nozzle 17 through the pressure chamber 10.

  The piezoelectric actuator 32 includes a vibration plate 41, a piezoelectric layer 42, and a plurality of individual electrodes 43. The diaphragm 41 is made of a conductive material such as metal, and is disposed on the upper surface of the cavity plate 21 so as to cover the plurality of pressure chambers 10, and is joined to the upper surface of the cavity plate 21. Further, the diaphragm 41 having conductivity also serves as a common electrode that sandwiches the piezoelectric layer 42 between the individual electrodes 43 and is always kept at the ground potential.

  The piezoelectric layer 42 is made of a piezoelectric material mainly composed of lead zirconate titanate, which is a mixed crystal of lead titanate and lead zirconate, and continuously on the upper surface of the vibration plate 41 across the plurality of pressure chambers 10. Has been placed. The piezoelectric layer 42 is polarized in the thickness direction at a portion sandwiched between the individual electrode 43 and the diaphragm 41.

  The plurality of individual electrodes 43 are provided corresponding to the plurality of pressure chambers 10. The individual electrode 43 has a substantially oval planar shape that is slightly smaller than the pressure chamber 10, and is disposed in a portion overlapping the substantially central portion of the pressure chamber 10. Further, the end of the individual electrode 43 opposite to the nozzle 17 in the longitudinal direction extends to the portion not facing the pressure chamber 10 and the manifold channel 11 in the scanning direction, and the tip thereof serves as a connection terminal 43a. The connection terminal 43a is connected to a driver IC (not shown) via a flexible printed circuit board (FPC) (not shown), and a drive potential is applied to the individual electrode 43 by the driver IC.

  Here, a driving method of the piezoelectric actuator 32 will be described. In the piezoelectric actuator 32, the diaphragm 41 as a common electrode and the plurality of individual electrodes 43 are both held at the ground potential in advance. When a driving potential is applied to any of the plurality of individual electrodes 43 by a driver IC (not shown), a potential difference is generated between the individual electrode 43 to which the driving potential is applied and the diaphragm 41, and the piezoelectric layer 42 An electric field in the thickness direction is generated in a portion sandwiched between these electrodes. Since the direction of the electric field coincides with the polarization direction of the piezoelectric layer 42, this portion of the piezoelectric layer 42 contracts in a horizontal direction orthogonal to the thickness direction, and the pressure chamber 10 of the vibration plate 41 and the piezoelectric layer 42. Is deformed so that the portion facing the surface becomes convex toward the pressure chamber 10 as a whole. As a result, the volume of the pressure chamber 10 is reduced, the pressure of the ink in the pressure chamber 10 is increased, and ink is ejected from the nozzle 17 communicating with the pressure chamber 10.

  At this time, a pressure wave is generated in the pressure chamber 10 due to an increase in ink pressure in the pressure chamber 10. The pressure wave propagates to the manifold channel 11 through the through hole 12, the throttle channel 13, the pressure wave attenuation space 14, and the through hole 15.

  Here, unlike the present embodiment, if the pressure wave attenuation space 14 is not provided, the pressure wave generated in the pressure chamber 10 propagates to the manifold channel 11 without being sufficiently attenuated. The pressure wave cannot be sufficiently attenuated in the flow path 11, the pressure wave further propagates to the other pressure chamber 10, and the ink ejection characteristics from the nozzles 17 communicating with the other pressure chamber 10 fluctuate. There is a risk of it.

  However, in the present embodiment, the cross-sectional area in the direction orthogonal to the channel axial direction is larger in the middle of the connection channel connecting the pressure chamber 10 and the manifold channel 11 than in other portions of the connection channel. Since the pressure wave attenuating space 14 is provided, the pressure wave generated in the pressure chamber 10 is attenuated in the pressure wave attenuating space 14 and then propagates to the manifold channel 11. Further attenuated. This prevents the pressure wave from propagating to the other pressure chamber 10 via the manifold channel 11.

  Furthermore, in the present embodiment, the connection flow path connecting the pressure chamber 10 and the manifold flow path 11 is bent at the connection portion between the throttle flow path 13 and the pressure wave attenuation space 14, and therefore from the pressure chamber 10 side. The pressure wave propagating to the pressure wave attenuation space 14 is reflected at the connection portion between the throttle channel 13 and the pressure wave attenuation space 14 and propagates so as to spread over the entire area of the pressure wave attenuation space 14. As a result, the pressure wave is effectively attenuated in the pressure wave attenuation space 14.

  At this time, the throttle channel 13 and the pressure wave attenuation space 14 are parallel, and the ends on the same side in the scanning direction of the throttle channel 13 and the pressure wave attenuation space 14 are connected to each other. The propagation direction of the pressure wave in the throttle channel 13 and the propagation direction of the pressure wave in the pressure wave attenuation space 14 are almost opposite to each other, and the pressure wave reflected at the connecting portion of both is surely the whole area of the pressure wave attenuation space 14. Propagate to spread.

  According to the embodiment described above, the cross-sectional area in the direction perpendicular to the axial direction of the flow channel is set in the middle of the connection flow channel connecting the pressure chamber 10 and the manifold flow channel 11 with respect to the other portion of the connection flow channel. Since the enlarged pressure wave attenuation space 14 is provided, the pressure wave generated in the pressure chamber 10 is attenuated in the pressure wave attenuation space 14 and then propagates to the manifold channel 11, and the manifold channel 11. Is further attenuated. Therefore, the pressure wave is prevented from propagating to the other pressure chamber 10 via the manifold channel 11.

  Further, since the connection flow path connecting the pressure chamber 10 and the manifold flow path 11 is bent at the connection portion between the throttle flow path 13 and the pressure wave attenuation space 14, the pressure wave attenuation space 14 is moved from the pressure chamber 10 side. The propagating pressure wave is reflected at the connection portion between the throttle channel 13 and the pressure wave attenuation space 14 and propagates so as to spread over the entire area of the pressure wave attenuation space 14. As a result, the pressure wave is effectively attenuated in the pressure wave attenuation space 14.

  At this time, the throttle channel 13 and the pressure wave attenuation space 14 are parallel, and the ends on the same side in the scanning direction of the throttle channel 13 and the pressure wave attenuation space 14 are connected to each other. The propagation direction of the pressure wave in the throttle channel 13 and the propagation direction of the pressure wave in the pressure wave attenuation space 14 are almost opposite to each other, and the pressure wave reflected at the connecting portion of both is surely the whole area of the pressure wave attenuation space 14. Propagate to spread.

  In the present embodiment, the through hole 12, the throttle channel 13, the pressure wave attenuation space 14, and the through hole 15, which are connection channels that connect the pressure chamber 10 and the manifold channel 11, are connected to the cavity plate 21 and the manifold. Since the aperture plate 22 and the base plate 23 disposed between the plate 24 and the base plate 23 are formed in a portion overlapping the pressure chamber 10 and the manifold channel 11 in a plan view, the through hole 12, the throttle channel 13, the pressure wave attenuation By forming the space 14 and the through hole 15, the plate does not increase in the surface direction, and as a result, the inkjet head 3 does not increase in size.

  In addition, the plates 22 and 23 are formed with through-holes and recesses that become the through-holes 12, the throttle channel 13, the pressure wave attenuation space 14, and the through-holes 15, and the plates 22 and 23 are connected to the cavity plate 21 and the manifold plate 24. By laminating, it is possible to easily form the connection flow paths (through hole 12, throttle flow path 13, pressure wave attenuation space 14 and through hole 15) in the plates 22 and 23.

  Next, modified examples in which various changes are made to the present embodiment will be described. However, components having the same configuration as in the present embodiment are denoted by the same reference numerals, and description thereof is omitted as appropriate.

  In one modification, as shown in FIG. 5, plates 51 and 52 are laminated between the cavity plate 21 and the manifold plate 24 instead of the aperture plate 22 (see FIG. 4) and the base plate 23 (see FIG. 4). Has been. A through hole 53 is formed in the plate 51 at a portion overlapping with the end of the pressure chamber 10 opposite to the nozzle 17 in plan view.

  The plate 52 to be joined to the upper surface of the manifold plate 24 is formed with a recess 52a serving as a throttle channel 54 and a pressure wave attenuation space 55 on the upper surface (the surface on the pressure chamber 10 side), and a through hole 56 ( A common liquid chamber side flow path) is formed. The throttle channel 54 and the pressure wave attenuation space 55 have the same planar shape as the throttle channel 13 (see FIG. 4) and the pressure wave attenuation space 14 (see FIG. 4), respectively. The throttle channel 13 and the pressure wave attenuation space 14 are disposed at the same positions. Thereby, the recessed part 52a used as the throttle flow path 54 and the pressure wave attenuation space 55 is located in the part which overlaps with the manifold flow path 11 by planar view. The through hole 65 is formed at the same position as the through hole 15 (see FIG. 4) in a plan view of the plate 52 (Modification 1).

  In this case, the through hole 53, the throttle channel 54, the pressure wave attenuation space 55, and the through hole 56 correspond to the connection channel according to the present invention, and the through hole 53 and the throttle channel 54 according to the present invention. It corresponds to the pressure chamber side flow path.

  Even in this case, as in the above-described embodiment, the connection in the direction perpendicular to the axial direction of the flow channel rather than other portions of the connection flow channel is intermediate in the connection flow channel connecting the pressure chamber 10 and the manifold flow channel 11. Since the pressure wave attenuation space 55 having an increased area is provided, the pressure wave generated in the pressure chamber 10 is attenuated in the pressure wave attenuation space 55 and then propagates to the manifold channel 11, and the manifold channel 11. Is further attenuated. Therefore, the pressure wave is prevented from propagating to the other pressure chamber 10 via the manifold channel 11.

  Also in this case, since the connection flow path is bent at the connection portion between the throttle flow path 54 and the pressure wave attenuation space 55, the pressure wave propagated from the pressure chamber 10 side to the pressure wave attenuation space 55 is restricted by the flow of the restriction flow. Since the light is reflected at the connection portion between the path 54 and the pressure wave attenuation space 55 and propagates so as to spread over the entire area of the pressure wave attenuation space 55, the pressure wave can be efficiently attenuated in the pressure wave attenuation space 55.

  Further, at this time, both the throttle channel 54 and the pressure wave attenuation space 55 extend in the scanning direction, and the end portions on the same side in both scanning directions are connected to each other. The propagation direction and the propagation direction of the pressure wave in the pressure wave attenuating space 55 are almost opposite to each other, and the pressure wave reflected at the connecting portion between both spreads reliably over the entire area of the pressure wave attenuating space 55.

  Also in this case, the through hole 53, the throttle channel 54, the pressure wave attenuation space 55, and the through hole 56 are pressure in plan view in the plates 51 and 52 disposed between the cavity plate 21 and the manifold plate 24. Since the through hole 53, the throttle channel 54, and the pressure wave attenuation space 55 are formed because the chamber 10 and the manifold channel 11 overlap with each other, the plate does not increase in the surface direction. As a result, the inkjet head does not increase in size.

  In addition, the plates 51 and 52 are formed with through-holes and recesses that become the through-holes 53, the throttle channels 54, the pressure wave attenuation spaces 55 and the through-holes 56, and the plates 51 and 52 are connected to the cavity plate 21 and the manifold plate 24. By laminating, connection plates (through holes 53, throttle channels 54, pressure wave attenuation spaces 55, and through holes 56) can be easily formed in the plates 51 and 52.

  Furthermore, in this case, the portion of the plate 52 that has become thinner due to the formation of the recess 52 a that becomes the throttle channel 54 and the pressure wave attenuation space 55 forms the upper surface of the manifold channel 11. Therefore, in addition to the deformation of the portion where the concave portion 18 of the damper plate 26 is formed and the thickness is reduced, the pressure wave in the manifold channel 11 is also generated by the deformation of the portion where the concave portion 52a of the plate 52 is formed and the thickness is reduced. Is attenuated. As a result, the pressure wave can be attenuated more efficiently in the manifold channel 11.

  In another modification, as shown in FIG. 6, the aperture plate 22 has a through hole 12 and a recess 22 a similar to those in the above-described embodiment, but unlike the above-described embodiment, The recess 22 a forms the throttle channel 13 and the upper end of the pressure wave attenuation space 62. On the upper surface of the base plate 23, a recess 23 a that forms a portion excluding the upper end portion of the pressure wave attenuation space 60 is formed in a portion overlapping the through hole 61 in plan view. Then, the concave portion 22a and the concave portion 23a overlap to form a pressure wave attenuation space 62 having a height higher than that of the pressure wave attenuation space 14 in the same position as the pressure wave attenuation space 14 (see FIG. 3) in plan view. Has been. In addition, a through hole 63 (common liquid chamber side flow path) is formed in the base plate 23 at the same position as the through hole 15 (see FIG. 4) in plan view (Modification 2).

  Even in this case, as in the above-described embodiment, the pressure wave generated in the pressure chamber 10 is attenuated in the pressure wave attenuation space 62, propagates to the manifold channel 11, and is further attenuated in the manifold channel 11. Therefore, the pressure wave is prevented from propagating to the other pressure chamber 10 via the manifold channel 11.

  Also in this case, since the connection flow path is bent at the connection portion between the throttle flow path 13 and the pressure wave attenuation space 62, the pressure wave propagated from the pressure chamber 10 side to the pressure wave attenuation space 62 is restricted to the restriction flow. Since the light is reflected at the connection portion between the path 13 and the pressure wave attenuation space 62 and propagates so as to spread over the entire area of the pressure wave attenuation space 62, the pressure wave can be efficiently attenuated in the pressure wave attenuation space 62.

  Further, at this time, both the throttle channel 13 and the pressure wave attenuation space 62 extend in the scanning direction, and the end portions on the same side in both scanning directions are connected to each other. The propagation direction and the propagation direction of the pressure wave in the pressure wave attenuating space 62 are almost opposite to each other, and the pressure wave reflected at the connecting portion between the both spreads reliably over the entire area of the pressure wave attenuating space 62.

  Also in this case, the through hole 12, the throttle channel 13, the pressure wave attenuation space 62, and the through hole 63 are seen in plan view in the plates 22 and 23 disposed between the cavity plate 21 and the manifold plate 24. Since the manifold channel 11 and the pressure chamber 10 overlap with each other, the through hole 12, the throttle channel 13, the pressure wave attenuation space 62, and the through hole 63 are formed, so that the plate becomes larger in the surface direction. As a result, the inkjet head is not enlarged.

  In addition, the plates 22 and 23 disposed between the cavity plate 21 and the manifold plate 24 are formed with through-holes and recesses that serve as the through-holes 12, the throttle channels 13, the pressure wave attenuation spaces 62, and the through-holes 63. By stacking the plates 22 and 23 with the cavity plate 21 and the manifold plate 24, the connection flow paths (through hole 12, throttle flow path 13, pressure wave attenuation space 62 and through hole 63) can be easily formed in the plates 22 and 23. Can be formed.

  Further, in this case, since the pressure wave attenuation space 62 is formed by overlapping the concave portion 22a and the concave portion 23a, the cross-sectional area in the direction orthogonal to the scanning direction (flow channel axis direction) of the pressure wave attenuation space 62 is formed. However, it is larger than the cross-sectional area of the pressure wave attenuation space 14 (see FIG. 4) formed by only the recess 22a in the direction perpendicular to the scanning direction (flow channel axis direction). Therefore, the pressure wave can be efficiently attenuated in the pressure wave attenuation space 62.

  In addition, in this case as well, as in the first modification, the thickness of the base plate 23 joined to the upper surface of the manifold plate 24 is reduced by forming the recess 23a on the upper surface (the surface on the pressure chamber 10 side). Since the portion forms the upper surface of the manifold channel 11, the thickness is reduced by forming the recess 23 a of the base plate 23 in addition to the deformation of the portion where the recess 18 of the damper plate 26 is formed and the thickness is reduced. The pressure wave in the manifold channel 11 is also attenuated by deformation of the thinned portion. As a result, the pressure wave can be attenuated more efficiently in the manifold channel 11.

  In another modification, as shown in FIG. 7 and FIG. 8, instead of the aperture plate 22 (see FIG. 4) and the base plate 23 (see FIG. 4), a 3 A single plate 71, 72, 73 is laminated. Here, FIGS. 8A to 8C are plan views on the plane A, the plane B, and the plane C of FIG. 7, respectively.

  In addition to the through-hole 12 similar to that of the above-described embodiment, the plate 71 is formed with a recess 71 a that is substantially the upper half of the throttle channel 74 and the channel 75 on the lower surface thereof. The throttle channel 74 is connected to the through hole 12 and extends in the scanning direction from the through hole 12 to a portion facing the substantially central portion in the longitudinal direction of the pressure chamber 10 in plan view. The flow path 75 extends from the end of the throttle flow path 74 opposite to the through hole 12 in a plan view to branch to both sides in the paper feed direction (vertical direction in FIG. 8), and also feeds the pressure chamber 10. In a portion that overlaps both ends in the direction, it is bent toward the through-hole 12 side in the scanning direction (right side in FIG. 8).

  In the plate 72, a through hole 72a penetrating the plate 72 is formed at a portion overlapping the flow path 75 in plan view, and a substantially lower half of the flow path 75 is formed by a substantially upper half of the through hole 72a. . In addition, a recess 72 b is formed in a portion of the lower surface of the plate 72 that faces the pressure chamber 10 on the side closer to the through hole 12 (right side in FIG. 8) than the flow path 75. The substantially lower half of the through hole 72a and the recess 72b are combined to form a pressure wave attenuation space 76. A through-hole 77 is formed in the plate 73 at a portion overlapping with the end portion on the through-hole 12 side in the scanning direction of the pressure wave attenuation space 76 in a plan view (Modification 3).

  In this case, the flow path including the through hole 12, the throttle flow path 74, the flow path 75, the pressure wave attenuation space 76, and the through hole 77, which connects the pressure chamber 10 and the manifold flow path 11, is the main flow path. The through hole 12, the throttle channel 74, and the channel 75 correspond to the pressure chamber side channel according to the present invention, and the through hole 77 corresponds to the common liquid chamber side according to the present invention. Corresponds to the flow path.

  In this case, the cross-sectional area of the pressure wave attenuation space 76 in the direction orthogonal to the scanning direction (channel axial direction) is orthogonal to the channel axial directions of the through hole 12, the throttle channel 74, and the channel 75. It is larger than the cross-sectional area in the direction. Here, the channel axis direction in the through hole 12 is a vertical direction, the channel axis direction in the throttle channel 74 is a scanning direction, and the channel axis direction in the channel 75 is a connection portion with the throttle channel 74. Is a direction in which it is bent to the right side of FIG. 8 in the scanning direction.

  Further, in this connection channel, the ends of the throttle channel 74 and the pressure wave attenuation space 76 on the side opposite to the through-hole 12 in the scanning direction (left side in FIG. 7) are the left ends of the channel 75 in FIG. Connected through. As a result, in FIG. 7, the connecting flow path is a portion (the pressure chamber side flow path and the pressure wave attenuation space 76 that extends from the left end of the throttle flow path 74 to the left end of the pressure wave attenuation space 76 through the left end of the flow path 75. Is bent at the connecting part). Therefore, the pressure wave generated in the pressure chamber 10 and propagated through the throttle channel 74 is reflected at this portion and propagates so as to spread over the entire pressure wave attenuation space 76. As a result, the pressure wave is efficiently attenuated in the pressure wave attenuation space 76.

  Further, in this case, the pressure wave propagated through the throttle channel 74 is reflected at the connection portion between the throttle channel 74 and the channel 75 and propagates separately to the two branched portions of the channel 75. Furthermore, since each of the branched portions of the flow path 75 propagates to different portions of the pressure wave attenuation space 76, the pressure wave further spreads over the entire pressure wave attenuation space 76. As a result, the pressure wave is attenuated more efficiently in the pressure wave attenuation space 76.

  Also in this case, the through hole 12, the throttle channel 74, the channel 75, the pressure wave attenuation space 76, and the through hole 77 are all plates 71 to 71 disposed between the cavity plate 21 and the manifold plate 24. 73 is disposed in a portion overlapping the pressure chamber 10 and the manifold channel 11 in plan view, so that the plate is formed by the through hole 12, the throttle channel 74, the channel 75, the pressure wave attenuation space 76, and the through hole 77. It does not increase in the surface direction, and as a result, the inkjet head does not increase in size.

  In addition, the plates 71 to 73 are formed with through-holes, recesses that become the through-holes 12, the throttle channels 74, the channels 75, the pressure wave attenuation spaces 76, and the through-holes 77, and the plates 71 to 73 are formed into By laminating with the manifold plate 24, connection channels (through holes 12, throttle channels 74, channels 75, pressure wave attenuation spaces 76 and through holes 77) can be easily formed in the plates 71 to 73.

  In the above-described embodiment, the throttle channel 13 and the pressure wave attenuation space 14 both extend in the scanning direction, and the end portions on the same side in the scanning direction are connected to each other, whereby the pressure chamber 10 and the manifold channel 11 are bent at the connecting portion between the throttle channel 13 and the pressure wave attenuation space 14, but the connection channel is connected to the extending direction of the throttle channel 13 and the pressure wave. As long as the connection portion with the attenuation space 14 is bent, the extending direction of the throttle channel 13 and the extending direction of the pressure wave attenuation space 14 may be different from each other.

  In the above-described embodiment, the connection flow path connecting the pressure chamber 10 and the manifold flow path 11 is bent at the connection portion between the throttle flow path 13 and the pressure wave attenuation space 14. I can't.

  In another modification, instead of the aperture plate 22 (see FIG. 4) and the base plate 23 (see FIG. 4), a plate is provided between the cavity plate 21 and the manifold plate 24 as shown in FIGS. 81-83 are laminated.

  The plate 81 is formed with the same through-hole 12 as in the embodiment, and the lower surface thereof is formed with a concavity 81 a that becomes the upper end of the throttle channel 84 and the pressure wave attenuation space 85. The plate 82 is formed with a through hole 82 a that is a portion excluding the upper end of the pressure wave attenuation space 85. And the pressure wave attenuation space 85 is formed by the recessed part 81a and the through-hole 82a overlapping. The plate 83 is formed with a through hole 86 (common liquid chamber side flow path).

  The throttle channel 84 is joined to the through hole 12 and extends from the through hole 12 to a portion overlapping the substantially central portion of the pressure chamber 10 in a plan view. It extends. Thereby, the cross-sectional area in the direction orthogonal to the vertical direction (flow channel axial direction) of the through hole 12 and the cross-sectional area in the direction orthogonal to the scanning direction (flow channel axial direction) of the throttle flow channel 84 are the pressure chamber 10. It is smaller than the cross-sectional area in the direction orthogonal to the scanning direction (flow channel axis direction).

  The pressure wave attenuation space 85 is connected to the end of the throttle channel 84 on the side opposite to the through hole 12 and has a substantially elliptical planar shape whose length in the scanning direction is shorter than that of the pressure chamber 10. Since the pressure wave attenuation space 85 has such a shape, the cross-sectional area in the direction orthogonal to the scanning direction (flow path axis direction) of the pressure wave attenuation space 85 is vertical to the through hole 12 (flow It is larger than the cross-sectional area in the direction orthogonal to the (path axis direction) and the cross-sectional area in the direction orthogonal to the scanning direction (flow path axis direction) of the throttle channel 84.

  The through hole 86 is formed in a portion of the plate 83 that overlaps with the vicinity of the end portion on the nozzle 17 side in the scanning direction of the pressure wave attenuation space 85 in a plan view, and a direction orthogonal to the vertical direction (flow channel axis direction). Is smaller than the cross-sectional area in the direction orthogonal to the scanning direction (flow channel axial direction) of the pressure wave attenuation space 85 (Modification 4).

  In this case, the flow path including the through hole 12, the throttle channel 84, the pressure wave attenuation space 85, and the through hole 86 corresponds to the connection channel according to the present invention, and the through hole 12 and the throttle channel 84. Is a pressure chamber side flow channel according to the present invention.

  In this case, the connection flow path is not bent at the connection portion between the throttle flow path 84 and the pressure wave attenuation space 85, and the pressure wave is not reflected at the connection portion between the throttle flow path 84 and the pressure wave attenuation space 85. Therefore, the pressure wave propagating from the throttle channel 84 to the pressure wave attenuation space 85 is difficult to spread throughout the pressure wave attenuation space 85. However, even in this case, the pressure wave generated in the pressure chamber 10 is a pressure wave attenuation space in which the cross-sectional area in the direction orthogonal to the channel axial direction is larger from the throttle channel 84 than the other part of the connection channel. 85, is attenuated in the pressure wave attenuation space 85, propagates from the through hole 86 to the manifold channel 11, and is further attenuated in the manifold channel 11. Propagation to the pressure chamber 10 is prevented.

  Also in this case, the through-hole 12, the throttle channel 84, the pressure wave attenuation space 85, and the through-hole 86 are all viewed from above the plates 81 to 83 arranged between the cavity plate 21 and the manifold plate 24. Since the through hole 12, the throttle channel 84, the pressure wave attenuation space 85, and the through hole 86 are formed, the plate is greatly increased in the surface direction. As a result, the inkjet head is not enlarged.

  In addition, the plates 81 to 83 are formed with through holes and recesses that become the through holes 12, the throttle channel 84, the pressure wave attenuation space 85 and the through holes 86, and the plates 81 to 83 are connected to the cavity plate 21 and the manifold plate 24. By laminating, it is possible to easily form connection channels (through holes 12, throttle channels 84, pressure wave attenuation spaces 85, and through holes 86) in the plates 81 to 83.

  In another modified example, as shown in FIGS. 11 and 12, the aperture plate 22 has the same through-hole 12 as in the embodiment, and the lower surface thereof has the throttle channel 84 similar to that in the modified example 4. A recess 22 b serving as a (pressure chamber side flow path) and a pressure wave attenuation space 92 is formed, and a through hole 93 (common liquid chamber side flow path) is formed in the base plate 23.

  The pressure wave attenuating space 92 is substantially oval in that the length in the scanning direction (left and right direction in FIG. 11) is shorter than the pressure chamber 10 and the length in the paper feeding direction (up and down direction in FIG. It has a planar shape and is connected to the end of the throttle channel 84 opposite to the through hole 12. The through-hole 93 is formed at the end on the nozzle 17 side in the scanning direction of the pressure wave attenuation space 92 in a plan view (Modification 5).

  In this case, the flow path including the throttle flow path 84, the pressure wave attenuation space 92, and the through hole 93 corresponds to the connection flow path according to the present invention, and the scanning direction of the pressure wave attenuation space 92 (flow path) The cross-sectional area in the direction orthogonal to the axial direction is orthogonal to the cross-sectional area in the direction orthogonal to the scanning direction of the throttle channel 84 (channel axial direction) and the vertical direction of the through-hole 93 (channel axial direction). It is larger than the cross-sectional area in the direction.

  Also in this case, the connection flow path is not bent at the connection portion between the throttle flow path 84 and the pressure wave attenuation space 92, and the pressure wave is not reflected at the connection portion between the restriction flow path 84 and the pressure wave attenuation space 92. Therefore, the pressure wave propagating from the throttle channel 84 to the pressure wave attenuation space 92 is difficult to spread over the entire area of the pressure wave attenuation space 92. However, even in this case, the pressure wave generated in the pressure chamber 10 is a pressure wave attenuation space in which the cross-sectional area in the direction orthogonal to the channel axial direction is larger from the throttle channel 84 than the other part of the connection channel. 92, is attenuated in the pressure wave attenuation space 92, propagates from the through hole 93 to the manifold channel 11, and is further attenuated in the manifold channel 11, so that the pressure wave passes through the manifold channel 11 to the other Propagation to the pressure chamber 10 is prevented.

  Also in this case, the through-hole 12, the throttle channel 84, the pressure wave attenuation space 92, and the through-hole 93 are all seen in a plan view of the plates 22 and 23 disposed between the cavity plate 21 and the manifold plate 24. Since the through hole 12, the throttle channel 84, the pressure wave attenuation space 92, and the through hole 93 are formed, the plate is greatly increased in the surface direction. As a result, the inkjet head is not increased in size.

  In addition, the plates 22 and 23 are formed with through-holes and recesses that become the through-holes 12, the throttle channels 84, the pressure wave attenuation spaces 92 and the through-holes 93, and the plates 22 and 23 are connected to the cavity plate 21 and the manifold plate 24. By laminating, it is possible to easily form the connection flow path (through hole 12, throttle flow path 84, pressure wave attenuation space 92 and through hole 93) in the plates 22 and 23.

  In the above description, two or more plates are disposed between the cavity plate 21 in which the pressure chamber 10 is formed and the manifold plates 24 and 25 in which the manifold channel 11 is formed. Further, although the connection flow path for connecting the pressure chamber 10 and the manifold flow path 11 is formed, the present invention is not limited to this.

  In another modification, as shown in FIGS. 13 and 14, only one plate 101 is disposed between the cavity plate 21 and the manifold plate 24. In the cavity plate 21, the pressure chamber 10 is formed, and a concavity 21 a serving as an upper end portion of the throttle channel 102 and the pressure wave attenuation space 103 is formed on the lower surface thereof. The plate 101 has a recess 101a formed on the upper surface of the plate 101 excluding the upper end of the pressure wave attenuation space 103, and a through hole 104. And the pressure wave attenuation space 103 is formed by the recessed part 21a and the recessed part 101a overlapping.

  The throttle channel 102 (pressure chamber side channel) is connected to the end of the pressure chamber 10 opposite to the nozzle 17 in the scanning direction and extends in the scanning direction. Further, the length of the throttle channel 102 in the paper feed direction (vertical direction in FIG. 13) is shorter than that of the pressure chamber 10, thereby orthogonal to the scanning direction (channel axis direction) of the throttle channel 102. The cross-sectional area with respect to the direction is smaller than the cross-sectional area with respect to the direction orthogonal to the scanning direction (flow channel axis direction) of the pressure chamber 10.

  The pressure wave attenuation space 103 has a substantially elliptical planar shape that is shorter in the scanning direction than the pressure chamber 10, and is thereby orthogonal to the scanning direction (flow channel axial direction) in the pressure wave attenuation space 103. The cross-sectional area with respect to the direction is larger than the cross-sectional area with respect to the direction orthogonal to the scanning direction (flow path axial direction) of the throttle channel 102.

  The end of the throttle channel 102 on the side opposite to the pressure chamber 10 in the scanning direction (the right side in FIG. 13) is the end on the pressure chamber 10 side in the scanning direction of the pressure wave attenuation space 103 (the left side in FIG. 13). It is connected. The through hole 104 (common liquid chamber side flow path) is formed in a portion that overlaps the end of the pressure wave attenuation space 103 opposite to the pressure chamber 10 in the scanning direction of the pressure wave attenuation space 103, and is perpendicular to the through hole 104. The cross-sectional area in the direction orthogonal to the (flow path axis direction) is smaller than the cross-sectional area in the direction orthogonal to the flow path axis direction of the pressure wave attenuation space 103 (Modification 6).

  In this case, the flow path including the throttle flow path 102, the pressure wave attenuation space 103, and the through hole 104 corresponds to the connection flow path according to the present invention.

  Also in this case, the connection flow path is not bent at the connection part between the throttle flow path 102 and the pressure wave attenuation space 103, and the pressure wave is not reflected at the connection part between the restriction flow path 102 and the pressure wave attenuation space 103. The pressure wave propagating from the throttle channel 102 to the pressure wave attenuation space 103 is difficult to spread over the entire area of the pressure wave attenuation space 103. However, even in this case, the pressure wave generated in the pressure chamber 10 is a pressure wave attenuation space in which the cross-sectional area in the direction orthogonal to the channel axial direction is larger from the throttle channel 102 than the other part of the connection channel. 103, is attenuated in the pressure wave attenuation space 103, propagates to the manifold channel 11, and is further attenuated in the manifold channel 11, so that the pressure wave passes through the manifold channel 11 to another pressure chamber 10. Propagation is prevented.

  Further, in this case, since the throttle channel 102, the pressure wave attenuation space 103, and the through hole 104 are arranged in a portion that overlaps the manifold channel 11 in a plan view, these portions do not overlap with the manifold channel 11. Compared with the arrangement, the throttle head 102, the pressure wave attenuation space 103, and the through hole 104 do not increase the size of the inkjet head.

  However, in this case, since the concave portion 101a that is the upper end portion of the throttle channel 102 and the pressure wave attenuation space 103 is formed in the same cavity plate 21 as the pressure chamber 10, the throttle channel 102 and the pressure wave attenuation space are formed. 103 cannot be formed in a portion overlapping the pressure chamber 10 in plan view. For this reason, compared with the case where the connection flow path is arranged so as to overlap the pressure chamber 10 and the manifold flow path 11, the plate becomes larger in the surface direction and the ink jet head becomes larger.

  In the above description, the pressure chamber 10, the manifold channel 11, and the pressure chamber 10 are connected to the manifold flow by laminating a plurality of plates in which through holes and recesses serving as pressure chambers and connection channels are formed. Although the connection flow path connecting the path 11 is formed, the present invention is not limited to this.

  In another modification, as shown in FIG. 15, the pressure chamber 10, the throttle channel 111 (pressure chamber side channel), the pressure wave attenuation space 112, and the channel 113 (common liquid chamber side flow) on one plane. Path) and a manifold channel 114 are formed. The throttle channel 111 is connected to the end of the pressure chamber 10 opposite to the nozzle 17 in the longitudinal direction and extends in the scanning direction. Further, the length of the throttle channel 111 in the paper feed direction (vertical direction in FIG. 15) is shorter than that of the pressure chamber 10, so that the throttle channel 111 is orthogonal to the scanning direction (channel axis direction) of the throttle channel 111. The cross-sectional area with respect to the direction in which the pressure chamber 10 performs is smaller than the cross-sectional area with respect to the direction orthogonal to the scanning direction (flow channel axis direction) of the pressure chamber 10.

  The pressure wave attenuation space 112 is disposed above the throttle channel 111 in FIG. 15 and extends in the scanning direction. Further, the pressure wave attenuation space 112 has a length in the paper feed direction that is larger than that of the throttle channel 111, and thus, a cut in a direction orthogonal to the scanning direction (channel axis direction) of the pressure wave attenuation space 112. The area is larger than the cross-sectional area in the direction orthogonal to the scanning direction (flow channel axial direction) of the throttle flow channel 111. Further, the right end portion of the throttle channel 111 in FIG. 15 and the lower right end portion of the pressure wave attenuation space 112 in FIG. 15 (the end portion on the same side of the pressure chamber side flow channel and the pressure wave attenuation space 112 in a predetermined direction). Are connected).

  The flow path 113 is disposed above the pressure wave attenuation space 112 in FIG. 15 and extends in the scanning direction. Further, the flow path 113 has a length in the paper feeding direction shorter than the pressure wave attenuation space 112, so that the cross-sectional area in the direction orthogonal to the scanning direction (flow path axial direction) of the flow path 113 is a pressure. It is smaller than the cross-sectional area of the wave attenuation space 112 in the direction orthogonal to the scanning direction (flow channel axis direction). And the upper left end part of FIG. 15 of the pressure wave attenuation space 112 and the left end part of FIG. 15 of the flow path 113 are connected.

  The manifold channel 114 is disposed on the side opposite to the pressure chamber 10 of the channel 113 in the scanning direction, and extends in the paper feeding direction. And the edge part on the opposite side to the pressure wave attenuation space 112 of the some flow path 113 and the manifold flow path 114 are connected (modification 7).

  In this case, the flow path including the throttle flow path 111, the pressure wave attenuation space 112, and the flow path 113 corresponds to the connection flow path according to the present invention. And this connection flow path has both ends of the narrow flow path 111 and the pressure wave attenuation space 112 extending in the scanning direction on the same side (right side in FIG. 15) in the scanning direction are connected. The connection part is bent.

  Also in this case, a pressure wave whose cross-sectional area in the direction orthogonal to the channel axial direction is larger than the other part of the connection channel in the middle of the connection channel connecting the pressure chamber 10 and the manifold channel 114. Since the attenuation space 112 is provided, the pressure wave generated in the pressure chamber 10 is attenuated in the pressure wave attenuation space 112, propagates to the manifold channel 114, and is further attenuated in the manifold channel 114. The Therefore, the pressure wave is prevented from propagating to the other pressure chamber 10 via the manifold channel 114.

  Further, since the connection channel is bent at the connection portion between the throttle channel 111 and the pressure wave attenuation space 112, the pressure wave generated in the pressure chamber 10 is connected to the throttle channel 111 and the pressure wave attenuation space 112. The light is reflected at the portion and propagates so as to spread over the entire pressure wave attenuation space 112. As a result, the pressure wave is efficiently attenuated in the pressure wave attenuation space 112.

  In addition, at this time, the throttle channel 111 and the pressure wave attenuation space 112 are parallel to each other, and end portions on the same side in the scanning direction of the throttle channel 111 and the pressure wave attenuation space 112 are connected to each other. Therefore, the propagation direction of the pressure wave in the throttle channel 111 and the propagation direction of the pressure wave in the pressure wave attenuation space 112 are almost opposite to each other, and the pressure wave reflected at the connecting portion between the two is surely reduced. It propagates so as to spread over the entire area 112.

  In the above description, pressure is applied to the ink in the pressure chamber 10 by driving the piezoelectric actuator. However, the present invention is not limited to this, and the ink in the pressure chamber 10 is applied by pressure applying means other than the piezoelectric actuator. Pressure may be applied.

  In the above, an example in which the present invention is applied to an inkjet head that ejects ink from nozzles has been described. However, the present invention is not limited to this, and the present invention is applied to a liquid transfer device that discharges and transfers liquids other than ink. Is also possible.

1 is a schematic configuration diagram of a printer according to an embodiment of the present invention. It is a top view of the inkjet head of FIG. FIG. 3 is a partially enlarged view of FIG. 2. It is the IV-IV sectional view taken on the line of FIG. FIG. 6 is a view corresponding to FIG. 4 of Modification 1; FIG. 6 is a diagram corresponding to FIG. FIG. 10 is a diagram corresponding to FIG. It is a top view in plane A, plane B, and plane C of FIG. FIG. 10 is a diagram corresponding to FIG. FIG. 10 is a diagram corresponding to FIG. FIG. 10 is a diagram corresponding to FIG. FIG. 10 is a diagram corresponding to FIG. FIG. 10 is a diagram corresponding to FIG. FIG. 10 is a diagram corresponding to FIG. FIG. 10 is a diagram corresponding to FIG.

Explanation of symbols

3 Inkjet head 10 Pressure chamber 11 Manifold flow path 12 Through hole 13 Restriction flow path 14 Pressure wave attenuation space 15 Through hole 21 Cavity plate 22 Aperture plate 23 Base plate 23a Recess 24, 25 Manifold plate 31 Flow path unit 32 Piezoelectric actuators 51, 52 Plate 52a Concavity 53 Through-hole 54 Restriction flow path 55 Pressure wave attenuation space 56 Through hole 60 Pressure wave attenuation space 63 Through hole 71-73 Plate 74 Restriction flow path 75 Channel 76 Pressure wave attenuation space 77 Through hole 81-83 Plate 84 Restriction flow path 85 Pressure wave attenuation space 86 Through hole 92 Pressure wave attenuation space 93 Through hole 101 Plate 102 Restriction flow path 103 Pressure wave attenuation space 104 Through hole 111 Restriction flow path 112 Pressure wave attenuation space 113 Flow path 114 Manifold flow path

Claims (9)

A plurality of pressure chambers, a common liquid chamber that supplies liquid to the plurality of pressure chambers, and a plurality of connection flow paths that respectively connect the plurality of pressure chambers and the common liquid chamber. A flow path unit formed by laminating a plurality of plates including a chamber and a plate provided with holes that can become flow paths;
Pressure applying means for applying pressure to the liquid in the pressure chamber,
Each of the plurality of connection channels is
Attenuating the pressure wave propagating in the connection flow path, which is provided in the middle and has a larger cross-sectional area in the direction orthogonal to the flow path axial direction than other portions of the plurality of connection flow paths Pressure wave attenuation space for,
A pressure chamber side flow path connecting the pressure wave attenuation space and the pressure chamber;
A liquid transfer device comprising a common liquid chamber side flow path connecting the pressure wave attenuation space and the common liquid chamber. The plurality of plates are
A pressure chamber plate in which the plurality of pressure chambers are formed;
A common liquid chamber plate in which the common liquid chamber is formed;
Including two or more plates stacked between the pressure chamber plate and the common liquid chamber plate,
The liquid transfer device according to claim 1, wherein the plurality of connection flow paths are formed in the two or more plates.   The plurality of connection flow paths are disposed in a portion overlapping at least one of the plurality of pressure chambers and the common liquid chamber as viewed from the stacking direction of the plurality of plates. The liquid transfer device described in 1.   The liquid transfer device according to claim 2, wherein the plurality of connection flow paths are bent at a connection portion between the pressure wave attenuation space and the pressure chamber side flow path. The pressure wave attenuation space, and at least a portion near the connection portion with the pressure wave attenuation space in the pressure chamber side flow path, both extend in a predetermined direction parallel to the surface direction of the plurality of plates,
The end portions on the same side in the predetermined one direction of the pressure wave attenuating space and the portion extending in the predetermined one direction of the pressure chamber side flow path are connected to each other. 5. The liquid transfer device according to 4. The pressure chamber side flow path is branched in the middle,
The liquid transfer device according to any one of claims 2 to 5, wherein the branched portions of the pressure chamber side flow path are respectively connected to different portions of the pressure wave attenuation space. The pressure wave attenuation space is
Of the two or more plates, formed by a recess formed in a portion overlapping the common liquid chamber as viewed from the stacking direction of the plurality of plates on the pressure chamber side surface of the plate joined to the common liquid chamber plate The liquid transfer device according to claim 2, wherein the liquid transfer device is provided. A flow path unit having a plurality of pressure chambers, a common liquid chamber that supplies liquid to the plurality of pressure chambers, and a plurality of connection flow paths that connect the plurality of pressure chambers and the common liquid chamber, respectively.
Pressure applying means for applying pressure to the liquid in the pressure chamber,
Each of the plurality of connection channels is
Attenuating the pressure wave propagating in the connection flow path, which is provided in the middle and has a larger cross-sectional area in the direction orthogonal to the flow path axial direction than other portions of the plurality of connection flow paths Pressure wave attenuation space for,
A pressure chamber side flow path connecting the pressure wave attenuation space and the pressure chamber;
Consists of a common liquid chamber side flow path connecting the pressure wave attenuation space and the common liquid chamber,
A liquid transfer device, wherein the pressure wave attenuating space and the pressure chamber side flow path are bent. The pressure wave attenuation space, and at least a portion near the connection portion with the pressure wave attenuation space in the pressure chamber side flow path, both extend in a predetermined direction parallel to the surface direction of the plurality of plates,
The end portions on the same side in the predetermined one direction of the pressure wave attenuating space and the portion extending in the predetermined one direction of the pressure chamber side flow path are connected to each other. 9. The liquid transfer device according to 8.

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