JP2018154065A - Liquid discharge head, liquid discharge unit, and apparatus for discharging liquid - Google Patents

Abstract

Dispersion of ejection characteristics due to pressure wave propagation to a discharge side common liquid chamber in a circulation type head is reduced. SOLUTION: A plurality of nozzles 4 for discharging liquid, a plurality of individual liquid chambers 6 communicating with the plurality of nozzles 4, a supply-side common liquid chamber 10 communicating with the plurality of individual liquid chambers 6, and a plurality of individual liquids A plurality of discharge-side fluid resistance portions 57 and one or a plurality of discharge-side derivation portions 58, and a plurality of discharge-side fluid resistance portions 57 and one or a plurality of discharge-side derivations constituting a plurality of discharge passages respectively communicating with the chamber 6 A discharge side common liquid chamber 50 communicating with the section 58, and a discharge side damper 85 that forms a wall surface of the discharge side common liquid chamber 50. [Selection] Figure 2

Description

  The present invention relates to a liquid discharge head, a liquid discharge unit, and an apparatus for discharging liquid.

  As a liquid discharge head for discharging liquid, by returning the liquid that was not discharged from the supply side common liquid chamber to the individual liquid chamber from the discharge channel to the discharge side common liquid chamber and circulating the liquid A circulation type head (flow-through head) is known which improves the discharge of bubbles mixed in individual liquid chambers and suppresses changes in liquid characteristics.

  Conventionally, a supply side damper is installed in a supply side flow path connected to each head module (liquid ejection head), and a discharge side damper is installed in a discharge side flow path (patent) Reference 1).

JP, 2006-187892 A

  By the way, in a non-circulating type liquid discharge head, in order to reduce variations in discharge characteristics due to a pressure wave generated along with liquid discharge propagating to the supply side common liquid chamber and repropagating to the individual liquid chamber side. In addition, a damper member for attenuating the pressure wave is disposed in the supply side common liquid chamber.

  On the other hand, in the circulation type head, since the discharge side common liquid chamber communicates with the individual liquid chamber through the discharge flow path, the pressure wave from the individual liquid chamber propagates to the discharge side common liquid chamber through the discharge flow path, There is a problem in that it travels back to the discharge channel again and affects the discharge characteristics.

  The present invention has been made in view of the above-described problems, and an object thereof is to reduce variations in ejection characteristics.

In order to solve the above problems, a liquid ejection head according to the present invention is
A plurality of nozzles for discharging liquid;
A plurality of individual liquid chambers respectively communicating with the plurality of nozzles;
A supply-side common liquid chamber communicating with the plurality of individual liquid chambers;
A plurality of discharge passages respectively communicating with the plurality of individual liquid chambers;
A discharge-side common liquid chamber communicating with the plurality of discharge channels,
A discharge-side damper that forms the wall surface of the discharge-side common liquid chamber is provided.

  According to the present invention, variation in ejection characteristics can be reduced.

FIG. 2 is an external perspective explanatory view of the liquid discharge head according to the first embodiment of the present invention. It is sectional explanatory drawing of the direction orthogonal to the nozzle arrangement direction of the head. It is the plane explanatory view which looked at each member of the head from the nozzle side. It is the plane explanatory view which looked at each member of the head from the opposite side to a nozzle. It is a disassembled perspective explanatory drawing of the head. FIG. 6 is a cross-sectional explanatory diagram in a direction orthogonal to a nozzle arrangement direction of a liquid ejection head according to a second embodiment of the present invention. It is the plane explanatory view which looked at each member of the head from the nozzle side. It is the plane explanatory view which looked at each member of the head from the opposite side to a nozzle. FIG. 10 is a cross-sectional explanatory diagram in a direction orthogonal to a nozzle arrangement direction of a liquid ejection head according to a third embodiment of the present invention. FIG. 10 is a cross-sectional explanatory diagram in a direction orthogonal to a nozzle arrangement direction of a liquid ejection head according to a fourth embodiment of the present invention. It is principal part plane explanatory drawing of an example of the apparatus which discharges the liquid which concerns on this invention. It is principal part side explanatory drawing of the apparatus. It is principal part plane explanatory drawing of the other example of the liquid discharge unit which concerns on this invention. It is front explanatory drawing of the further another example of the liquid discharge unit which concerns on this invention. It is a schematic explanatory drawing of the other example of the apparatus which discharges the liquid based on this invention. It is a plane explanatory view of the head unit of the device. FIG. 2 is a block explanatory diagram for explaining an example of a liquid circulation system in the apparatus.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. A liquid discharge head according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an external perspective view illustrating the liquid discharge head, and FIG. 2 is a cross-sectional explanatory view in a direction perpendicular to the nozzle arrangement direction of the head.

  In this liquid discharge head, a nozzle plate 1, a flow path plate 2, and a vibration plate member 3 as a wall surface member are laminated and joined. The piezoelectric actuator 11 that displaces the vibration region (vibration plate) 30 of the vibration plate member 3, the common liquid chamber member 20 that also serves as a frame member of the head, and a cover 29 are provided.

  The nozzle plate 1 has a plurality of nozzles 4 that discharge liquid.

  The flow path plate 2 is connected to the individual liquid chamber 6 communicating with the nozzle 4 via the nozzle communication path 5, the supply side fluid resistance portion 7 constituting the supply flow path leading to the individual liquid chamber 6, and the supply leading to the supply side fluid resistance portion 7. A side introduction portion 8 is formed. The supply-side introduction unit 8 can be configured to communicate with one or more supply-side fluid resistance units 7.

  The vibration plate member 3 has a deformable vibration region 30 that forms the wall surface of the individual liquid chamber 6 of the flow path plate 2. Here, the diaphragm member 3 has a two-layer structure (not limited), and is formed of a first layer that forms a thin portion and a second layer that forms a thick portion from the flow path plate 2 side. A deformable vibration region 30 is formed in a portion corresponding to the individual liquid chamber 6.

  Then, on the opposite side of the diaphragm member 3 from the individual liquid chamber 6, a piezoelectric actuator 11 including an electromechanical conversion element as drive means (actuator means, pressure generating means) for deforming the vibration region 30 of the diaphragm member 3 is provided. It is arranged.

  The piezoelectric actuator 11 forms grooves in the piezoelectric member 12 bonded on the base member 13 by half-cut dicing so that a required number of columnar piezoelectric elements 12A and 12B are comb-toothed at predetermined intervals in the nozzle arrangement direction. Forming.

  The piezoelectric element 12 </ b> A is joined to a convex portion 30 a that is an island-shaped thick portion formed in the vibration region (vibration plate) 30 of the vibration plate member 3. Further, the piezoelectric element 12 </ b> B is joined to the thick part of the diaphragm member 3 between the individual liquid chambers 6.

  The piezoelectric member 12 is formed by alternately laminating piezoelectric layers and internal electrodes. The internal electrodes are drawn out to end faces, external electrodes are provided, and the flexible wiring member 15 is connected to the external electrodes.

  The common liquid chamber member 20 forms a supply side common liquid chamber 10 and a discharge side common liquid chamber 50. The supply-side common liquid chamber 10 communicates with the supply port 41, and the discharge-side common liquid chamber 50 communicates with the discharge port 42 (FIG. 1).

  The supply-side common liquid chamber 10 communicates with the supply-side introduction unit 8 via the supply-side filter 9. The supply side filter 9 is formed by the first layer of the diaphragm member 3.

  In addition, the flow path plate 2 forms a discharge side fluid resistance portion 57 and a discharge side lead-out portion 58 that constitute a discharge flow path that communicates with each individual liquid chamber 6 via the nozzle communication path 5. In addition, the discharge | emission side derivation | leading-out part 58 can be set as the structure connected to the 1 or several discharge side fluid resistance part 57. FIG.

  The discharge side lead-out portion 58 communicates with the discharge side common liquid chamber 50 via the discharge side filter 59. The discharge side filter 59 is formed by the first layer of the diaphragm member 3.

  In the liquid discharge head configured as described above, for example, by lowering the voltage applied to the piezoelectric element 12A from the reference potential (intermediate potential), the piezoelectric element 12A contracts, and the vibration region 30 of the diaphragm member 3 is drawn, so that the individual liquid As the volume of the chamber 6 expands, the liquid flows into the individual liquid chamber 6.

  Thereafter, the voltage applied to the piezoelectric element 12A is increased to extend the piezoelectric element 12A in the stacking direction, and the vibration region 30 of the diaphragm member 3 is deformed in the direction toward the nozzle 4 to contract the volume of the individual liquid chamber 6. As a result, the liquid in the individual liquid chamber 6 is pressurized, and the liquid is discharged from the nozzle 4.

  Further, the liquid that is not discharged from the nozzle 4 passes through the nozzle 4 and is discharged from the discharge side fluid resistance portion 57 to the discharge side common liquid chamber 50 via the discharge side derivation portion 58, and from the discharge side common liquid chamber 50 to the external circulation path. Then, it is supplied again to the supply-side common liquid chamber 10. Further, even when the liquid is not discharged, the liquid flows from the supply-side common liquid chamber 10 to the discharge-side common liquid chamber 50 and is supplied again to the supply-side common liquid chamber 10 through an external circulation path.

  Note that the driving method of the head is not limited to the above example (drawing-pushing), and it is also possible to perform striking or pushing depending on the direction to which the drive waveform is given.

  Next, the structure of the common liquid chamber in the liquid discharge head according to the present embodiment will be described with reference to FIG.

  The common liquid chamber member 20 is configured by sequentially laminating the first member 21, the second member 22, the damper chamber member 83, the damper member 81, the damper chamber member 82, and the third member 23 from the diaphragm member 3 side. A supply-side common liquid chamber 10 and a discharge-side common liquid chamber 50 are formed.

  The supply-side common liquid chamber 10 has a downstream common liquid chamber portion 10A that is a portion aligned with the discharge-side common liquid chamber 50 and an upstream portion that is not aligned with the discharge-side common liquid chamber 50 in a direction orthogonal to the nozzle arrangement direction. Side common liquid chamber portion 10B.

  The discharge side common liquid chamber 50 and the supply side common liquid chamber 10 have overlapping portions when one is projected onto the other in the direction perpendicular to the nozzle surface. Here, when the part 10b of the upstream common liquid chamber part 10B and the discharge side common liquid chamber 50 are projected, the part overlaps (hereinafter, part 10b is referred to as "overlapping part 10b").

  The damper member 81 forms a discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 and a supply side damper 86 that forms the wall surface of the supply side common liquid chamber 10.

  The damper chamber member 82 forms a damper chamber (gas chamber) 87 on the opposite side of the discharge side common liquid chamber 50 with the discharge side damper 85 interposed therebetween. The damper chamber member 83 forms a damper chamber (gas chamber) 88 on the opposite side of the supply-side common liquid chamber 10 from the upstream-side common liquid chamber portion 10B with the supply-side damper 86 interposed therebetween.

  Thus, the discharge side damper 85 which forms the wall surface of the discharge side common liquid chamber 50 is provided. Thereby, when the pressure wave accompanying the liquid discharge propagates to the discharge side common liquid chamber 50 through the discharge side fluid resistance portion 57 and the discharge side derivation portion 58, the pressure wave can be attenuated or absorbed by the discharge side damper 85. Repropagation to the nozzle 4 side can be prevented. Therefore, it is possible to reduce variations in discharge characteristics due to the pressure wave repropagating from the discharge side common liquid chamber 50 to the nozzle 4 side.

  A supply-side damper 86 that forms the wall surface of the supply-side common liquid chamber 10 is also provided. Thereby, when the pressure wave accompanying the liquid discharge propagates to the supply-side common liquid chamber 10 through the supply-side fluid resistance unit 7 and the supply-side introduction unit 8, the supply-side damper 86 can attenuate or absorb the pressure wave. Further, repropagation to the individual liquid chamber 6 side can be prevented. Therefore, it is possible to reduce variation in discharge characteristics due to repropagation of the pressure wave from the supply-side common liquid chamber 10 to the individual liquid chamber 6 side.

  In this embodiment, since the discharge side damper 85 and the supply side damper 86 are formed by the same damper member 81, the number of parts can be reduced and the configuration is simplified.

  In the present embodiment, the supply-side damper 86 is the wall surface of the upstream-side common liquid chamber portion 10B in the supply-side common liquid chamber 10, and the overlapping portion 10b where the projection position overlaps with the discharge-side common liquid chamber 50. It is arranged on the wall.

  Accordingly, the supply-side damper 86 and the discharge-side damper 85 can be provided without increasing the head size while securing the supply-side common liquid chamber 10 and the discharge-side common liquid chamber 50 with sufficient capacity.

  Therefore, the pressure wave is also attenuated on the discharge side and the supply side in the same manner, so that the supply side and the discharge side are reversed, that is, the supply side is used as the discharge side and the discharge side is used as the supply side. You can also.

  Here, each part which comprises the liquid discharge head of this embodiment is demonstrated with reference to FIG. 3 thru | or FIG. 3 is an explanatory plan view of each member of the head as seen from the nozzle side, FIG. 4 is an explanatory plan view of the members of the head as seen from the side opposite to the nozzle, and FIG. 5 is an exploded perspective view of the head. .

  A plurality of nozzles 4 are formed on the nozzle plate 1 as shown in FIGS. 3 (a) and 4 (a).

  As shown in FIGS. 3B to 3E and FIGS. 4B to 4E, the flow path plate 2 includes plate-like members 2A to 2D.

  As shown in FIGS. 3 (c) and 4 (b), the plate-like member 2 </ b> A of the flow path plate 2 includes a part of the nozzle communication path 5, a discharge side fluid resistance portion 57, and a discharge side lead-out portion 58. A through-groove portion (meaning a groove-shaped through hole) 57b is formed.

  Similarly, as shown in FIGS. 3C and 4C, the plate-like member 2 </ b> B is formed with a through hole 5 c that forms a part of the nozzle communication path 5 and a part of the discharge side lead-out part 58. A through groove portion 58c is formed.

  Similarly, in the plate-like member 2C, as shown in FIGS. 3D and 4D, a through hole 5d that forms a part of the nozzle communication passage 5 and a through groove that forms the supply side fluid resistance portion 7 are formed. 7d and a through groove portion 58d that forms a part of the discharge side outlet portion 58 are formed.

  Similarly, as shown in FIGS. 3E and 4E, the plate-like member 2D includes a through groove portion 6e that forms the individual liquid chamber 6, a through groove portion 8e that forms the supply side introduction portion 8, and a discharge. A through groove portion 58 e that forms a part of the side lead-out portion 58 is formed.

  As shown in FIGS. 3 (f) and 4 (f), a supply side filter 9 and a discharge side filter 59 are formed on the diaphragm member 3.

  As shown in FIGS. 3 (g) and 4 (g), the first member 21 constituting the common liquid chamber member 20 includes a through groove 10g that forms a part of the supply-side common liquid chamber 10, and a discharge side. A through groove portion 50 g that forms a part of the common liquid chamber 50 is formed. Further, the first member 21 includes a through hole 42g that forms a part of the internal flow path of the discharge port 42, and a through groove part that forms a part of the actuator housing part 24 (see FIG. 2) that houses the piezoelectric actuator 11. 24g is formed.

  Similarly, in the damper chamber member 83, as shown in FIGS. 3 (h) and 4 (h), a through groove 10 h that forms a part of the supply-side common liquid chamber 10 and a part of the discharge-side common liquid chamber 50. A through-groove 50h that forms a recess and a recess 88h that forms a damper chamber 88 are formed. Further, the damper chamber member 83 is formed with a through hole 42 h that forms a part of the internal flow path of the discharge port 42 and a through groove part 24 h that forms a part of the actuator housing part 24.

  Similarly, in the damper member 81, as shown in FIGS. 3 (i) and 4 (i), a through groove portion 10i forming a part of the supply side common liquid chamber 10 and a part of the discharge side common liquid chamber 50 are provided. A through-groove portion 50i to be formed, a discharge side damper 85, and a supply side damper 86 are formed. Further, the damper member 81 is formed with a through hole 42 i that forms a part of the internal flow path of the discharge port 42 and a through groove part 24 i that forms a part of the actuator housing part 24.

  Similarly, in the damper chamber member 82, as shown in FIGS. 3 (j) and 4 (j), through-groove portions 10 j 1 and 10 j 2 that form a part of the supply-side common liquid chamber 10, and the discharge-side common liquid chamber 50. A through-groove 50j that forms a part and a recess 87j that forms a damper chamber 87 are formed. Further, the damper chamber member 82 is formed with a through hole 42 j that forms a part of the internal flow path of the discharge port 42 and a through groove part 24 j that forms a part of the actuator housing part 24.

  Similarly, as shown in FIGS. 3 (k) and 4 (k), the second member 22 has a through-groove 10k that forms a part of the supply-side common liquid chamber 10. Further, the second member 22 includes a through hole 41 k that forms a part of the internal flow path of the supply port 41, a through hole 42 k that forms a part of the internal flow path of the discharge port 42, and the actuator housing portion 24. A through groove portion 24k constituting a part is formed.

  Similarly, in the third member 23, as shown in FIGS. 3 (l) and 4 (l), a through groove 24k constituting a part of the actuator housing 24 and a part of the supply side common liquid chamber 10 are formed. The through-groove portion 10k, the through-hole 41k that forms a part of the internal flow path of the supply port 41, and the through-hole 42k that forms a part of the internal flow path of the discharge port 42 are formed.

  As shown in FIGS. 3 (m) and 4 (m), piezoelectric elements 12A and 12B are formed on the piezoelectric member 12.

  Next, a liquid ejection head according to a second embodiment of the present invention will be described with reference to FIG. FIG. 6 is a cross-sectional explanatory diagram in a direction orthogonal to the nozzle arrangement direction of the head.

  In the present embodiment, in the direction orthogonal to the nozzle arrangement direction, the supply-side common liquid chamber 10, the supply-side introduction portion 8, and the supply-side fluid resistance portion 7 are arranged on one side across the nozzle 4, and the supply side Liquid is supplied from the common liquid chamber 10 to the individual liquid chamber 6.

  Here, the supply side introduction section 8 communicates with the plurality of supply side fluid resistance sections 7. As a result, even when the supply-side filter 9 is clogged with time, the liquid can be supplied bypassing the clogged portion, so that an increase in pressure loss can be suppressed.

  Further, in the direction orthogonal to the nozzle arrangement direction, the discharge side fluid resistance portion 57, the discharge side derivation portion 58, and the discharge side common liquid chamber 50 are arranged on the other side across the nozzle 4 and discharged from the nozzle communication path 5. The liquid is discharged into the side common liquid chamber 50.

  Here, the discharge-side derivation unit 58 includes an individual derivation unit 58A that communicates with each discharge-side fluid resistance unit 57 and one or a plurality of common derivation units 58B that communicate with a plurality of individual derivation units 58A in common. Yes. As a result, even when the discharge filter 59 is clogged with time, the liquid can be discharged around the clogged portion, so that an increase in pressure loss can be suppressed.

  The supply-side common liquid chamber 10 and the discharge-side common liquid chamber 50 are formed by a common liquid chamber member 20, and a damper member 81 and a damper chamber member 84 are stacked on the common liquid chamber member 20. The damper member 81 forms a discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 and a supply side damper 86 that forms the wall surface of the supply side common liquid chamber 10. The damper chamber member 84 forms damper chambers 87 and 88.

  As in the present embodiment, the supply side and the discharge side are arranged on opposite sides of the nozzle row, so that the compliance on the supply side and the discharge side can be easily made the same.

  Moreover, since the flow path shape can be made substantially the same shape on the supply side and the discharge side, and the pressure loss can be easily made the same, the supply side and the discharge side can be used interchangeably. As a result, when a long head is configured by arranging a plurality of liquid discharge heads according to the present embodiment, various piping methods are possible when piping to the supply port and the discharge port.

  Next, each part constituting the liquid ejection head of this embodiment will be described with reference to FIGS. 7 is an explanatory plan view of each member of the head as viewed from the nozzle side, and FIG. 8 is an explanatory plan view of the members of the head as viewed from the side opposite to the nozzle.

  A plurality of nozzles 4 are formed on the nozzle plate 1 as shown in FIGS.

  As shown in FIGS. 7B to 7D and FIGS. 4B to 4D, the flow path plate 2 includes plate-like members 2A to 2C.

  As shown in FIGS. 7C and 8B, the plate-like member 2A of the flow path plate 2 includes a part of the nozzle communication path 5, a part of the discharge side fluid resistance part 57, and a part of the individual outlet part 58A. A through groove portion (meaning a groove-shaped through hole) 57b is formed.

  Similarly, in the plate-like member 2B, as shown in FIGS. 7C and 8C, a through groove portion 7c that forms the supply side fluid resistance portion 7 and a through hole that forms a part of the nozzle communication passage 5 are formed. 5c and the through-groove part 58c which forms a part of individual derivation | leading-out part 58A are formed.

  Similarly, in the plate-like member 2C, as shown in FIGS. 7 (d) and 8 (d), as shown in FIGS. 7 (d) and 8 (d), a through groove 6d that forms the individual liquid chamber 6 is provided. In addition, a through groove portion 8d that forms the supply side introduction portion 8 and a through groove portion 58d that forms a part of the common lead-out portion 58B are formed.

  As shown in FIGS. 7E and 8E, the diaphragm member 3 is provided with a supply side filter 9 and a discharge side filter 59.

  As shown in FIGS. 7 (f) and 8 (f), the common liquid chamber member 20 is formed with a through groove 10 f that forms a part of the supply-side common liquid chamber 10 and a discharge-side common liquid chamber 50. A through groove portion 50f is formed. Further, the common liquid chamber member 20 includes a through hole 42 f that forms a part of the internal flow path of the discharge port 42, a through hole 41 f that forms a part of the internal flow path of the supply port 41, and the actuator housing portion 24. A through-groove portion 24f that constitutes a part of is formed.

  As shown in FIGS. 7G and 8G, the damper member 81 is formed with a discharge side damper 85 and a supply side damper 86. Further, the damper member 81 has a through hole 42 g that forms a part of the internal flow path of the discharge port 42, a through hole 41 g that forms a part of the internal flow path of the supply port 41, and one of the actuator housing portions 24. The through-groove part 24g which comprises a part is formed.

  As shown in FIGS. 7 (h) and 8 (h), the damper chamber member 84 is formed with a recess 87j that forms the damper chamber 87 and a recess 88j that forms the damper chamber 88. The damper chamber member 84 includes a through hole 42 j that forms a part of the internal flow path of the discharge port 42, a through hole 41 j that forms a part of the internal flow path of the supply port 41, and the actuator housing portion 24. A through groove portion 24j constituting a part is formed.

  As shown in FIGS. 7 (i) and 8 (i), the holding member 25 (not shown in FIG. 6) includes a through hole 41 i that forms a part of the internal flow path of the supply port 41, and a discharge port 42. A through hole 42 i that forms a part of the internal flow path and a through groove part 24 i that forms a part of the actuator housing part 24 are formed.

  Piezoelectric elements 12A and 12B are formed on the piezoelectric member 12 as shown in FIGS. 7 (j) and 8 (j).

  Next, a liquid ejection head according to a third embodiment of the invention will be described with reference to FIG. FIG. 9 is a cross-sectional explanatory diagram in a direction orthogonal to the nozzle arrangement direction of the head.

  In the present embodiment, the discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 and the supply side damper 86 that forms the wall surface of the supply side common liquid chamber 10 are formed by separate damper members 81A and 81B. Yes.

  Thus, by using the discharge side damper 85 and the supply side damper 86 as separate members, it is possible to increase the degree of freedom in arranging the damper and to increase (enlarge) the damper area.

  That is, in this embodiment, the discharge side damper 85 is disposed on the entire wall surface in the direction orthogonal to the nozzle arrangement direction of the discharge side common liquid chamber 50. Similarly, the upstream common liquid chamber portion 10B of the supply side common liquid chamber 10 is enlarged until the entire discharge side common liquid chamber 50 is overlapped, and then orthogonal to the nozzle arrangement direction of the upstream common liquid chamber portion 10B. It is arranged on the entire wall in the direction.

  Thus, damper efficiency can be improved by increasing the damper area.

  Further, since the supply-side damper 86 is disposed so as to face the direction in which the pressure wave from the individual liquid chamber 6 advances straight in the supply-side common liquid chamber 10, the damper efficiency is improved also in this respect.

  Next, a liquid discharge head according to a fourth embodiment of the invention will be described with reference to FIG. FIG. 10 is a cross-sectional explanatory view in a direction orthogonal to the nozzle arrangement direction of the head.

  In the present embodiment, the discharge side common liquid chamber 50 and the supply side common liquid chamber 10 are formed side by side by the common liquid chamber member 20, and the damper member 81 and the damper chamber member 84 are stacked on the common liquid chamber member 20. Yes. The damper member 81 forms a discharge side damper 85 that forms the wall surface of the discharge side common liquid chamber 50 and a supply side damper 86 that forms the wall surface of the supply side common liquid chamber 10. The damper chamber member 84 forms damper chambers 87 and 88.

  Even if comprised in this way, the discharge side damper 85 and the supply side damper 86 can be formed by the same member, and the straight line direction of the pressure wave propagating to the discharge side common liquid chamber 50 and the supply side common liquid chamber 10 A discharge side damper 85 and a supply side damper 86 can be arranged opposite to each other.

  Next, an example of an apparatus for ejecting liquid according to the present invention will be described with reference to FIGS. FIG. 11 is an explanatory plan view of the main part of the apparatus, and FIG. 12 is an explanatory side view of the main part of the apparatus.

  This apparatus is a serial type apparatus, and the carriage 403 reciprocates in the main scanning direction by the main scanning moving mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, and the like. The guide member 401 spans the left and right side plates 491A and 491B and holds the carriage 403 so as to be movable. The carriage 403 is reciprocated in the main scanning direction by the main scanning motor 405 via the timing belt 408 spanned between the driving pulley 406 and the driven pulley 407.

  A liquid discharge unit 440 in which the liquid discharge head 404 and the head tank 441 according to the present invention are integrated is mounted on the carriage 403. The liquid discharge head 404 of the liquid discharge unit 440 discharges, for example, yellow (Y), cyan (C), magenta (M), and black (K) liquids. The liquid ejection head 404 is mounted with a nozzle row composed of a plurality of nozzles arranged in the sub-scanning direction orthogonal to the main scanning direction, and the ejection direction facing downward.

  The liquid stored in the liquid cartridge 450 is supplied to the head tank 441 by the supply mechanism 494 for supplying the liquid stored outside the liquid discharge head 404 to the liquid discharge head 404.

  The supply mechanism 494 includes a cartridge holder 451 that is a filling unit for mounting the liquid cartridge 450, a tube 456, a liquid feeding unit 452 including a liquid feeding pump, and the like. The liquid cartridge 450 is detachably attached to the cartridge holder 451. Liquid is fed from the liquid cartridge 450 to the head tank 441 by the liquid feeding unit 452 via the tube 456.

  This apparatus includes a transport mechanism 495 for transporting the paper 410. The transport mechanism 495 includes a transport belt 412 serving as transport means, and a sub-scanning motor 416 for driving the transport belt 412.

  The conveyance belt 412 adsorbs the paper 410 and conveys it at a position facing the liquid ejection head 404. The transport belt 412 is an endless belt and is stretched between the transport roller 413 and the tension roller 414. The adsorption can be performed by electrostatic adsorption or air suction.

  The transport belt 412 rotates in the sub-scanning direction when the transport roller 413 is rotationally driven by the sub-scanning motor 416 via the timing belt 417 and the timing pulley 418.

  Further, on one side of the carriage 403 in the main scanning direction, a maintenance / recovery mechanism 420 that performs maintenance / recovery of the liquid ejection head 404 is disposed on the side of the transport belt 412.

  The maintenance / recovery mechanism 420 includes, for example, a cap member 421 for capping the nozzle surface (surface on which the nozzle is formed) of the liquid ejection head 404, a wiper member 422 for wiping the nozzle surface, and the like.

  The main scanning movement mechanism 493, the supply mechanism 494, the maintenance / recovery mechanism 420, and the transport mechanism 495 are attached to a housing including the side plates 491A and 491B and the back plate 491C.

  In this apparatus configured as described above, the paper 410 is fed and sucked onto the transport belt 412, and the paper 410 is transported in the sub-scanning direction by the circular movement of the transport belt 412.

Therefore, the liquid ejection head 404 is driven in accordance with the image signal while moving the carriage 403 in the main scanning direction, thereby ejecting liquid onto the stopped paper 410 to form an image.

  Thus, since this apparatus includes the liquid ejection head according to the present invention, a high-quality image can be stably formed.

  Next, another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 13 is an explanatory plan view of the main part of the unit.

  The liquid discharge unit includes a casing portion composed of side plates 491A and 491B and a back plate 491C, a main scanning moving mechanism 493, a carriage 403, and a liquid among the members constituting the liquid discharge device. The discharge head 404 is configured.

  Note that a liquid discharge unit in which at least one of the above-described maintenance and recovery mechanism 420 and the supply mechanism 494 is further attached to, for example, the side plate 491B of the liquid discharge unit may be configured.

  Next, still another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 14 is an explanatory front view of the unit.

  This liquid discharge unit includes a liquid discharge head 404 to which a flow path component 444 is attached, and a tube 456 connected to the flow path component 444.

  The flow path component 444 is disposed inside the cover 442. A head tank 441 may be included instead of the flow path component 444. In addition, a connector 443 that is electrically connected to the liquid ejection head 404 is provided above the flow path component 444.

  Next, another example of an apparatus for ejecting liquid according to the present invention will be described with reference to FIGS. FIG. 15 is a schematic explanatory view of the apparatus, and FIG. 16 is a plan explanatory view of a head unit of the apparatus.

  This apparatus includes a carry-in means 501 for carrying in the continuous medium 510, a guide carrying means 503 for guiding and carrying the continuous medium 510 carried from the carry-in means 501 to the printing means 505, and discharging liquid to the continuous medium 510. A printing unit 505 that performs printing for forming an image, a drying unit 507 that dries the continuous medium 510, and a discharge unit 509 that discharges the continuous medium 510 are provided.

  The continuous medium 510 is fed out from the original winding roller 511 of the carry-in means 501, guided and conveyed by the respective rollers of the carry-in means 501, the guide conveyance means 503, the drying means 507 and the discharge means 509, and the take-up roller 591 of the discharge means 509. It is wound up by.

  The continuous medium 510 is conveyed by the printing unit 505 on the conveyance guide member 559 so as to face the head unit 550 and the head unit 555, and an image is formed by the liquid ejected from the head unit 550. Post-processing is performed with the processing liquid.

  Here, the head unit 550 includes, for example, full-line head arrays 551K, 551C, 551M, and 551Y for four colors from the upstream side in the medium conveying direction (hereinafter referred to as “head array 551” when colors are not distinguished). ) Is arranged.

  Each head array 551 is a liquid ejecting unit, and ejects black K, cyan C, magenta M, and yellow Y liquids to the transported continuous medium 510, respectively. The type and number of colors are not limited to this.

  The head array 551 includes, for example, a plurality of liquid ejection heads (hereinafter also simply referred to as “heads”) 1000 according to the present invention arranged in a staggered manner on the base member 552, but is not limited thereto. .

  Next, an example of the liquid circulation system in this apparatus will be described with reference to FIG. FIG. 17 is a block diagram for explaining the system.

  The liquid circulation system 630 includes a main tank 602, a head 1000, a supply tank 631, a circulation tank 632, a compressor 633, a vacuum pump 634, a first liquid feed pump 635, a second liquid feed pump 636, a supply side pressure sensor 637, and a circulation side. A pressure sensor 638, regulators (R) 639a, 639b, and the like are included.

  The supply-side pressure sensor 637 is connected between the supply tank 631 and the head 1000, and is connected to a supply-side flow path connected to the supply port 41 (see FIG. 1) of the head 1000. The circulation side pressure sensor 638 is connected between the head 1000 and the circulation tank 632 and is connected to a discharge side flow path connected to the discharge port 42 (see FIG. 1) of the head 1000.

  One of the circulation tanks 632 is connected to the supply tank 631 via the first liquid feed pump 635, and the other of the circulation tanks 632 is connected to the main tank 602 via the second liquid feed pump 636.

  As a result, liquid flows from the supply tank 631 through the supply port 41 into the head 1000, is discharged from the discharge port 42, and is discharged to the circulation tank 632. Further, the liquid is circulated by the liquid being further fed from the circulation tank 632 to the supply tank 631 by the first liquid feed pump 635.

  In addition, a compressor 633 is connected to the supply tank 631, and the supply side pressure sensor 637 is controlled so as to detect a predetermined positive pressure. On the other hand, a vacuum pump 634 is connected to the circulation tank 632 and is controlled so that a predetermined negative pressure is detected by the circulation side pressure sensor 638.

  Thereby, the negative pressure of the meniscus can be kept constant while circulating the liquid through the head 1000.

  Further, when the liquid is discharged from the nozzle 4 of the head 1000, the amount of liquid in the supply tank 631 and the circulation tank 632 decreases. Therefore, the liquid is replenished from the main tank 602 to the circulation tank 632 using the second liquid feeding pump 636 as appropriate. The liquid replenishment timing from the main tank 602 to the circulation tank 632 is the liquid level provided in the circulation tank 632 such that liquid replenishment is performed when the liquid level of the liquid in the circulation tank 632 falls below a predetermined height. It can be controlled by the detection result of a sensor or the like.

  In the present application, the liquid to be ejected is not particularly limited as long as it has a viscosity and surface tension that can be ejected from the head, and the viscosity becomes 30 mPa · s or less at room temperature, normal pressure, or by heating and cooling. It is preferable. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, functional materials such as polymerizable compounds, resins, and surfactants, and biocompatible materials such as DNA, amino acids, proteins, and calcium. , Edible materials such as natural pigments, solutions, suspensions, emulsions, and the like. These include, for example, inkjet inks, surface treatment liquids, components of electronic devices and light emitting devices, and formation of electronic circuit resist patterns. It can be used in applications such as liquids for use, three-dimensional modeling material liquids, and the like.

  As energy generation sources for discharging liquid, piezoelectric actuators (laminated piezoelectric elements and thin film piezoelectric elements), thermal actuators using electrothermal transducers such as heating resistors, electrostatic actuators consisting of a diaphragm and counter electrode are used. To be included.

  The “liquid ejection unit” is a unit in which functional parts and mechanisms are integrated with a liquid ejection head, and includes an assembly of parts related to liquid ejection. For example, the “liquid discharge unit” includes a combination of at least one of a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, and a main scanning movement mechanism with a liquid discharge head.

  Here, the term “integrated” refers to, for example, a liquid discharge head, a functional component, and a mechanism that are fixed to each other by fastening, adhesion, engagement, etc., and one that is held movably with respect to the other. Including. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

  For example, there is a liquid discharge unit in which a liquid discharge head and a head tank are integrated. Also, there are some in which the liquid discharge head and the head tank are integrated by being connected to each other by a tube or the like. Here, a unit including a filter may be added between the head tank and the liquid discharge head of these liquid discharge units.

  In addition, there is a liquid discharge unit in which a liquid discharge head and a carriage are integrated.

  In addition, there is a liquid discharge unit in which the liquid discharge head and the scanning movement mechanism are integrated by holding the liquid discharge head movably on a guide member that constitutes a part of the scanning movement mechanism. In some cases, a liquid discharge head, a carriage, and a main scanning movement mechanism are integrated.

  Also, there is a liquid discharge unit in which a cap member that is a part of the maintenance / recovery mechanism is fixed to a carriage to which the liquid discharge head is attached, and the liquid discharge head, the carriage, and the maintenance / recovery mechanism are integrated. .

  In addition, there is a liquid discharge unit in which a tube is connected to a liquid discharge head to which a head tank or a flow path component is attached, and the liquid discharge head and a supply mechanism are integrated. The liquid from the liquid storage source is supplied to the liquid discharge head via this tube.

  The main scanning movement mechanism includes a guide member alone. The supply mechanism includes a single tube and a single loading unit.

The “apparatus for ejecting liquid” includes an apparatus that includes a liquid ejection head or a liquid ejection unit and that ejects liquid by driving the liquid ejection head. The apparatus for ejecting a liquid includes not only an apparatus capable of ejecting a liquid to an object to which the liquid can adhere, but also an apparatus for ejecting the liquid into the air or liquid.

  This “apparatus for discharging liquid” may include means for feeding, transporting, and discharging a liquid to which liquid can adhere, as well as a pre-processing apparatus and a post-processing apparatus.

  For example, as a “liquid ejecting device”, an image forming device that forms an image on paper by ejecting ink, a powder is formed in layers to form a three-dimensional model (three-dimensional model) There is a three-dimensional modeling apparatus (three-dimensional modeling apparatus) that discharges a modeling liquid onto the powder layer.

  Further, the “apparatus for ejecting liquid” is not limited to an apparatus in which significant images such as characters and figures are visualized by the ejected liquid. For example, what forms a pattern etc. which does not have a meaning in itself, and what forms a three-dimensional image are also included.

  The above-mentioned “applicable liquid” means that the liquid can be attached at least temporarily and adheres and adheres, or adheres and penetrates. Specific examples include recording media such as paper, recording paper, recording paper, film, and cloth, electronic parts such as electronic substrates and piezoelectric elements, powder layers (powder layers), organ models, and test cells. Yes, unless specifically limited, includes everything that the liquid adheres to.

  The material of the above-mentioned “material to which liquid can adhere” is not limited as long as liquid such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics can be adhered even temporarily.

  In addition, the “device for ejecting liquid” includes a device in which the liquid ejection head and the device to which the liquid can adhere move relatively, but is not limited thereto. Specific examples include a serial type apparatus that moves the liquid discharge head, a line type apparatus that does not move the liquid discharge head, and the like.

  In addition, as the “device for ejecting liquid”, other than the above, a treatment liquid coating apparatus that ejects a treatment liquid onto a sheet in order to apply the treatment liquid to the surface of the sheet for the purpose of modifying the surface of the sheet, There is an injection granulation apparatus that granulates raw material fine particles by spraying a composition liquid in which raw materials are dispersed in a solution through a nozzle.

  Note that the terms “image formation”, “recording”, “printing”, “printing”, “printing”, “modeling” and the like in the terms of the present application are all synonymous.

DESCRIPTION OF SYMBOLS 1 Nozzle plate 2 Flow path plate 3 Vibrating plate 4 Nozzle 5 Nozzle communication path 6 Individual liquid chamber 10 Supply side common liquid chamber 11 Piezoelectric actuator 20 Common liquid chamber member 50 Discharge side common liquid chamber 57 Discharge side fluid resistance part 58 Discharge side derivation 85 Discharge side damper 86 Supply side damper 87 Damper chamber 88 Damper chamber 403 Carriage 404 Liquid discharge head 440 Liquid discharge unit 630 Liquid circulation system 1000 Liquid discharge head

Claims (9)

A plurality of nozzles for discharging liquid;
A plurality of individual liquid chambers respectively communicating with the plurality of nozzles;
A supply-side common liquid chamber communicating with the plurality of individual liquid chambers;
A plurality of discharge passages respectively communicating with the plurality of individual liquid chambers;
A discharge-side common liquid chamber communicating with the plurality of discharge channels,
A liquid discharge head comprising a discharge side damper that forms a wall surface of the discharge side common liquid chamber. The liquid discharge head according to claim 1, further comprising a supply-side damper that forms a wall surface of the supply-side common liquid chamber. The liquid discharge head according to claim 2, wherein the discharge side damper and the supply side damper are integrated members. The supply-side common liquid chamber and the discharge-side common liquid chamber have overlapping portions when one is projected onto the other in the direction perpendicular to the nozzle surface,
4. The liquid ejection head according to claim 2, wherein at least one of the supply-side damper and the discharge-side damper is disposed in the overlapping portion. 5. The supply-side common liquid chamber has a portion that is not aligned with a portion that is aligned with the discharge-side common liquid chamber in a direction orthogonal to the nozzle arrangement direction,
The liquid discharge head according to claim 2, wherein the supply-side damper is disposed in a portion of the supply-side common liquid chamber that is not aligned with the discharge-side common liquid chamber. The liquid discharge head according to claim 2, wherein the supply side common liquid chamber and the discharge side common liquid chamber are arranged on opposite sides of the nozzle row.   A liquid discharge unit comprising the liquid discharge head according to claim 1. A head tank for storing liquid to be supplied to the liquid discharge head, a carriage on which the liquid discharge head is mounted, a supply mechanism for supplying liquid to the liquid discharge head, a maintenance / recovery mechanism for maintaining and recovering the liquid discharge head, and the liquid The liquid discharge unit according to claim 7, wherein at least one of a main scanning movement mechanism that moves the discharge head in a main scanning direction and the liquid discharge head are integrated.   An apparatus for discharging a liquid, comprising the liquid discharge head according to claim 1 or the liquid discharge unit according to claim 7 or 8.

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