JP2018154067A - Liquid discharge head, liquid discharge unit, and apparatus for discharging liquid - Google Patents

Abstract

Dispersion of discharge characteristics in a circulation type head is reduced. SOLUTION: A nozzle 4 for discharging liquid, an individual liquid chamber 6 communicating with the nozzle 4, and two supply side fluid resistance portions 7A constituting a supply flow path for communicating with the individual liquid chamber 6 and supplying the liquid, 7B, two supply-side introduction portions 8A and 8B, a supply-side common liquid chamber 10, and an individual liquid chamber 6 through a nozzle communication path 5 to form one discharge flow path for discharging the liquid 2 Two discharge-side fluid resistance portions 57A and 57B, two discharge-side lead-out portions 58A and 58B, and a discharge-side common liquid chamber 50 are provided. [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 that discharges liquid, liquid that was not discharged out of the liquid supplied to the individual liquid chamber is returned from the discharge channel to the common liquid chamber on the discharge side, and mixed into the individual liquid chamber by circulating the liquid. A circulation type head is known which improves the discharge performance of the bubbles and suppresses the change in liquid characteristics.

  Conventionally, a plurality of droplet ejection elements including a nozzle for ejecting droplets, a pressure chamber communicating with the nozzle, and a piezoelectric element for displacing the wall surface of the pressure chamber, and a plurality of droplet ejection elements are supplied to each Some have a common flow path that communicates with each other via a path and a common circulation path that communicates with each of a plurality of droplet discharge elements via a recovery path (Patent Document 1).

JP 2014-188837 A

  In the circulation type head, since the liquid always flows in the head, there is a problem that the discharge characteristics vary between nozzles or between heads due to variations in fluid resistance on the discharge flow path side.

  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 nozzle for discharging liquid;
An individual liquid chamber communicating with the nozzle;
A supply flow path for supplying the liquid in communication with the individual liquid chamber;
A discharge passage communicating with the individual liquid chamber and discharging the liquid, and
It was set as the structure which has the at least 2 discharge side fluid resistance part which comprises one said discharge flow path.

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

1 is an external perspective view illustrating a liquid discharge head according to a 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 a decomposition plane explanatory view for 1 nozzle of the flow path plate and nozzle plate of the head. It is sectional explanatory drawing along the direction orthogonal to the nozzle arrangement direction of a comparative example. It is an exploded top view for 1 nozzle of a channel plate and a nozzle plate similarly. It is explanatory drawing of the electrical equivalent circuit for 1 nozzle of a comparative example. It is explanatory drawing of an electrical equivalent circuit when the some nozzle of a comparative example is arranged. It is explanatory drawing of distribution of electric potential VA corresponding to the meniscus pressure in FIG. It is explanatory drawing of the electrical equivalent circuit for 1 nozzle of 1st Embodiment. It is explanatory drawing of an electrical equivalent circuit when the some nozzle of 1st Embodiment is arranged. It is explanatory drawing of distribution of electric potential VA corresponding to the meniscus pressure in FIG. It is sectional explanatory drawing in alignment with the direction orthogonal to the nozzle arrangement direction of 2nd Embodiment of this invention. It is an exploded top view for 1 nozzle of a channel plate and a nozzle plate similarly. It is sectional explanatory drawing in alignment with the direction orthogonal to the nozzle arrangement direction of 3rd Embodiment of this invention. It is an exploded top view for 1 nozzle of a channel plate and a nozzle plate similarly. It is sectional explanatory drawing which follows the direction orthogonal to the nozzle arrangement direction of 4th Embodiment of this invention. It is a decomposition | disassembly top view for 1 nozzle of the flow-path board and nozzle plate of 5th Embodiment of this 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. A portion constituted by the flow path plate 2 and the diaphragm member 3 is referred to as a flow path member 40.

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

  The flow path plate 2 includes an individual liquid chamber 6 that communicates with the nozzle 4 via the nozzle communication path 5, and two supply side fluid resistance portions 7A and 7B that constitute a supply flow path that communicates with the individual liquid chamber 6 (hereinafter not distinguished). In some cases, it is referred to as “supply-side fluid resistance portion 7” (the same applies to other members), and a supply-side introduction portion 8 communicating with each supply-side fluid resistance portion 7 is formed. Here, the two supply-side fluid resistance units 7A and 7B are arranged in different planes.

  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 three-layer structure (not limited), and is formed of a first layer that forms a thin portion from the flow path plate 2 side, a second layer that forms a thick portion, and a third layer. A deformable vibration region 30 is formed in a portion corresponding to the individual liquid chamber 6 in the first layer.

  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 has a predetermined number of columnar piezoelectric elements 12 formed at a predetermined interval, for example, by grooving a piezoelectric member by half-cut dicing. The piezoelectric element 12 is bonded 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.

  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 through the filter member 9. The filter member 9 is formed by the first layer of the diaphragm member 3.

  The flow path plate 2 includes two discharge-side fluid resistance portions 57A and 57B and two discharge-side lead-out portions 58A and 58B that constitute a discharge flow path communicating with each individual liquid chamber 6 via the nozzle communication path 5. Is forming. The two discharge side fluid resistance portions 57A and 57B are arranged in different planes.

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

  In the liquid discharge head configured as described above, for example, the voltage applied to the piezoelectric element 12 is lowered from the reference potential (intermediate potential), so that the piezoelectric element 12 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 12 is increased to extend the piezoelectric element 12 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.

  At this time, in this embodiment, since the two discharge-side fluid resistance portions 57A and 57B that constitute the discharge flow path are provided, the discharge-side fluid is compared with the case where one discharge-side fluid resistance portion 57 is provided. It is possible to reduce variations in discharge characteristics due to variations in manufacturing of the resistance portion. Details of this point will be described later.

  Further, the liquid that is not discharged from the nozzle 4 passes through the nozzle 4 and is discharged from the individual discharge channel 51 to the discharge side common liquid chamber 50, and from the discharge side common liquid chamber 50 to the supply side common liquid chamber 10 through the external circulation path. Will be supplied again. 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, an example of the flow path plate in the present embodiment will be described with reference to FIG. FIG. 3 is an exploded plan view for explaining one nozzle of the flow path plate and the nozzle plate.

  As shown in FIGS. 3A to 3H, the flow path plate 2 is formed by laminating eight plate members 2A to 2H from the vibration plate member 3 side toward the nozzle plate 1 of FIG. 3I. Configured.

  As shown in FIG. 3A, the plate-like member 2A includes two through-groove portions (meaning groove-like through-holes) 6a that form the individual liquid chambers 6 and two portions that form part of the supply-side introduction portion 8. A through groove portion 8 a and two through groove portions 58 a forming a part of the discharge side outlet portion 58 are formed.

  As shown in FIG. 3B, the plate-like member 2B includes a through-groove portion 5b that forms a part of the nozzle communication path 5, a fluid resistance portion 7A, a part of the supply side introduction portion 8A, and a fluid resistance portion 7A. A through groove 7b that forms a flow path between the liquid chamber 6 and the individual liquid chamber 6, a through groove 8b that forms a part of the supply side introduction part 8B, and two through groove parts that form a part of the discharge side lead-out part 58 58b is formed.

  As shown in FIG. 3C, the plate-like member 2 </ b> C has a through groove portion 5 c that forms a part of the nozzle communication path 5 and a through hole that forms a flow path between the fluid resistance portion 7 </ b> A and the individual liquid chamber 6. A groove portion 7c, a through hole portion 8c that forms a part of the supply side introduction portion 8B, and two through groove portions 58c that form a portion of the discharge side lead-out portion 58 are formed.

  As shown in FIG. 3D, the plate-like member 2D includes a through-groove part 5d that forms part of the nozzle communication path 5, a fluid resistance part 7B, a part of the supply side introduction part 8B, and a fluid resistance part 7B. A through-groove portion 7d that forms a flow path between the individual liquid chamber 6 and two through-groove portions 58d that form a part of the discharge-side lead-out portion 58 is formed.

  As shown in FIG. 3E, the plate-like member 2 </ b> E is formed with a through groove portion 5 e that forms a part of the nozzle communication path 5 and two through groove portions 58 e that form a part of the discharge side lead-out portion 58. ing.

  As shown in FIG. 3 (f), the plate-like member 2F includes a through groove portion 57f that forms a part of the discharge side lead-out portion 58A together with a part of the nozzle communication passage 5 and the discharge side fluid resistance portion 57B, and a discharge side A through groove portion 58f that forms a part of the lead-out portion 58B is formed.

  As shown in FIG. 3G, the plate-like member 2G is formed with a through groove portion 5g that forms a part of the nozzle communication path 5 and a through groove portion 58g that forms a part of the discharge side outlet portion 58B. .

  As shown in FIG. 3 (h), the plate-like member 2H has a through groove portion 57h that forms a part of the discharge side outlet portion 58A together with a part of the nozzle communication path 5 and the discharge side fluid resistance portion 57B. Yes.

  Next, reduction in variation in fluid resistance value by providing a plurality of discharge-side fluid resistance units will be described.

  First, a comparative example will be described with reference to FIGS. 4 is a cross-sectional explanatory diagram along a direction orthogonal to the nozzle arrangement direction of the comparative example, and FIG. 5 is an exploded plan view of one nozzle of the flow path plate and the nozzle plate.

  This comparative example is configured to have one supply side introduction portion 8, one supply side fluid resistance portion 7, one discharge side fluid resistance portion 57, and one discharge side introduction portion 58.

  In this comparative example, as shown in FIG. 5, the flow path plate 2 is constituted by four plate-like members 2A to 2D.

  As shown in FIG. 5A, the plate-like member 2A includes a through groove portion 6a that forms the individual liquid chamber 6, a through groove portion 8a that forms a part of the supply side introduction portion 8, and a discharge side lead-out portion. A through-groove 58 a that forms a part of 58 is formed.

  As shown in FIG. 5B, the plate-like member 2B includes a through groove portion 5b that forms a part of the nozzle communication passage 5, a through groove portion 7b that forms the supply side fluid resistance portion 7, and a discharge side lead-out portion 58. A through-groove 58b that forms a part of is formed.

  As shown in FIG. 5C, the plate-like member 2 </ b> C is formed with a through groove portion 5 c that forms a part of the nozzle communication path 5 and a through groove portion 58 c that forms a part of the discharge side lead-out portion 58. .

  As shown in FIG. 5D, the plate-like member 2 </ b> D is formed with a through groove portion 57 d that forms a part of the nozzle communication path 5, a discharge side fluid resistance portion 57, and a part of the discharge side lead-out portion 58. .

  Here, an electrical equivalent circuit when a pressure is applied to one individual liquid chamber 6 is as shown in FIG. That is, the pressure of the supply-side common liquid chamber 10 is V1, the combined fluid resistance value of the supply-side introduction portion 8 and the supply-side fluid resistance portion 7 is R1, and the combined fluid vessel value of the discharge-side fluid resistance portion 57 and the discharge-side derivation portion 58. Is R2, and the pressure of the discharge side common liquid chamber 50 is V2, the pressure applied to the nozzle 4 corresponds to the potential VA of the node A.

  The potential VA is obtained by the equation (1).

  In the head, since a plurality of nozzles 4 are arranged, an electrical equivalent circuit is as shown in FIG.

  At this time, the potential VA related to the node An has a distribution as shown in FIG. 8 due to manufacturing variations. The potential VA represents the pressure applied to the nozzle 4, that is, the meniscus state stretched in the nozzle hole, and the fact that the potential VA has a distribution means that the meniscus state of each nozzle 4 has a distribution.

  As described above, when the meniscus state is different between individual nozzles, it leads to a difference (variation) in the discharge speed and discharge volume (discharge characteristics) of the droplets, and as a result, the image quality is deteriorated.

  On the other hand, as in the present embodiment, for one nozzle 4, the two supply side introduction portions 8, the two supply side fluid resistance portions 7, the two discharge side fluid resistance portions 57, and the two discharge side derivation portions 58 are provided. FIG. 9 shows an electrical equivalent circuit having a configuration including the above. That is, a circuit in which the fluid resistance is bridge-connected to the node A is obtained.

  Since the head includes a plurality of nozzles 4, an electrical equivalent circuit is as shown in FIG.

  At this time, the potential VA related to the node An has a distribution due to manufacturing variations, but as shown in FIG. 11, the distribution of the present embodiment is smaller than the distribution of the comparative example indicated by the broken line ( Narrow).

  When the potential distribution at the node An is reduced, the distribution of meniscus pressure is reduced. As a result, variations in volume and speed of the ejected droplets are reduced, and good image quality can be obtained.

  Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 12 is a cross-sectional explanatory diagram along a direction orthogonal to the nozzle arrangement direction of the same embodiment, and FIG. 13 is an exploded plan view of one nozzle of the flow path plate and the nozzle plate.

  In the present embodiment, one supply side introduction portion 8 common to the two supply side fluid resistance portions 7A and 7B is disposed, and one discharge side lead-out portion 58 common to the two discharge side fluid resistance portions 57A and 57B is provided. It is arranged.

  Here, as shown in FIGS. 13A to 13H, the flow path plate 2 has eight plate-like members 2A to 2A to the nozzle plate 1 in FIG. 13I from the vibration plate member 3 side. 2H is laminated.

  As shown in FIG. 13A, the plate-like member 2 </ b> A includes a through groove portion 6 a that forms the individual liquid chamber 6, a through groove portion 8 a that forms a part of the supply side introduction portion 8, and the discharge side lead-out portion 58. A through-groove 58a that forms a part is formed.

  As shown in FIG. 13B, the plate-like member 2B includes a through-groove part 5b that forms a part of the nozzle communication path 5, a fluid resistance part 7A, a part of the supply side introduction part 8, and a fluid resistance part 7A. And a through groove portion 58 b that forms a part of the discharge side outlet portion 58 are formed.

  As shown in FIG. 13C, the plate-like member 2 </ b> C has a through groove portion 5 c that forms a part of the nozzle communication path 5 and a through hole that forms a flow path between the fluid resistance portion 7 </ b> A and the individual liquid chamber 6. A groove portion 7c, a through hole portion 8c that forms a part of the supply side introduction portion 8, and a through groove portion 58c that forms a portion of the discharge side lead-out portion 58 are formed.

  As shown in FIG. 13 (d), the plate-like member 2D includes a part of the supply side introduction part 8 and the fluid resistance part 7B together with the through groove part 5d that forms part of the nozzle communication path 5 and the fluid resistance part 7B. A through-groove portion 7d that forms a flow path between the individual liquid chamber 6 and a through-groove portion 58d that forms a part of the discharge side lead-out portion 58 is formed.

  As shown in FIG. 13E, the plate-like member 2 </ b> E is formed with a through groove portion 5 e that forms a part of the nozzle communication path 5 and a through groove portion 58 e that forms a part of the discharge side lead-out portion 58. .

  As shown in FIG. 13 (f), the plate-like member 2 </ b> F is formed with a through groove portion 57 f that forms a part of the discharge side outlet portion 58 together with a part of the nozzle communication path 5 and the discharge side fluid resistance portion 57 </ b> B. Yes.

  As shown in FIG. 13G, the plate-like member 2G is formed with a through groove portion 5g that forms a part of the nozzle communication passage 5 and a through groove portion 58g that forms a part of the discharge side lead-out portion 58B. .

  As shown in FIG. 13 (h), the plate-like member 2H is formed with a through groove portion 57h that forms a part of the discharge side lead-out portion 58 together with a part of the nozzle communication path 5 and the discharge side fluid resistance portion 57B. Yes.

  In the present embodiment, since the discharge side derivation portion 58 is common to the two discharge side fluid resistance portions 57A and 57B, the filter area of the filter member 59 facing the discharge side derivation portion 58 is increased, and the bubble discharge property is increased. improves.

  Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 14 is a cross-sectional explanatory diagram along a direction orthogonal to the nozzle arrangement direction of the embodiment, and FIG. 15 is an exploded plan view of one nozzle of the flow path plate and the nozzle plate.

  In the present embodiment, the two supply-side fluid resistance units 7A and 7B are arranged in the same plane, and similarly, the two discharge-side fluid resistance units 57A and 57B are arranged in the same plane. Therefore, one common supply-side introduction portion 8 is disposed in the two supply-side fluid resistance portions 7A and 7B, and one common discharge-side lead-out portion 58 is disposed in the two discharge-side fluid resistance portions 57A and 57B.

  Here, as shown in FIGS. 15A to 15E, the flow path plate 2 includes five plate-like members 2 </ b> A to 2 </ b> A from the vibration plate member 3 side toward the nozzle plate 1 of FIG. 2E is laminated.

  As shown in FIG. 15A, the plate-like member 2 </ b> A includes a through groove portion 6 a that forms the individual liquid chamber 6, a through groove portion 8 a that forms a part of the supply side introduction portion 8, and the discharge side lead-out portion 58. A through-groove 58a that forms a part is formed.

  As shown in FIG. 15B, the plate-like member 2B includes a through groove portion 5b that forms a part of the nozzle communication passage 5, and two supply-side fluid resistance portions 7A and 7B. And two through groove portions 7b that form a flow path between the two supply side fluid resistance portions 7A and 7B and the individual liquid chamber 6, and a through groove portion 58b that forms a part of the discharge side outlet portion 58 are formed. ing. The two through-groove parts 7b and 7b that form the two supply-side fluid resistance parts 7A and 7B are arranged in the same plane.

  As shown in FIG. 15C, the plate-like member 2 </ b> C is formed with a through groove portion 5 c that forms a part of the nozzle communication path 5 and a through groove portion 58 c that forms a part of the discharge side lead-out portion 58. .

  As shown in FIG. 15 (d), the plate-like member 2 </ b> D has two through groove portions that form part of the nozzle communication passage 5, two discharge side fluid resistance portions 57 </ b> A and 57 </ b> B, and part of the discharge side lead-out portion 58. 57d is formed in the same plane.

  As shown in FIG. 15E, the plate-like member 2 </ b> E is formed with a through groove portion 5 e that forms a part of the nozzle communication path 5.

  In the present embodiment, the thickness (height) can be reduced by arranging (disposing) the plurality of discharge-side fluid resistance portions 57A and 57B in the same plane. The filter area of the filter member 59 opposed to the discharge side derivation portion 58 common to the discharge side fluid resistance portions 57A and 57B is increased, and the bubble discharge performance is improved.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 16 is a cross-sectional explanatory diagram along a direction orthogonal to the nozzle arrangement direction of the same embodiment.

  In the present embodiment, in the first embodiment, the supply side is one supply-side fluid resistance portion 7, and only the discharge side is two discharge-side fluid resistance portions 57A and 57B.

  Even if a plurality of discharge-side fluid resistance portions are arranged, the discharge side in the electrical equivalent circuit of FIG. 10 does not change in a bridge arrangement, so the meniscus pressure distribution can be reduced correspondingly, and the discharge characteristics vary. Can be reduced.

  Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 17 is an exploded plan view of one nozzle of the flow path plate and the nozzle plate of the same embodiment. In addition, since the cross-sectional explanatory drawing along the direction orthogonal to the nozzle arrangement direction of the embodiment is the same as FIG.

  In the third embodiment, the supply side is one supply-side fluid resistance portion 7 and the discharge side is two discharge-side fluid resistance portions 57A and 57B in the third embodiment.

  Even in this case, similar to the fourth embodiment, the distribution of the meniscus pressure can be reduced, and variations in the discharge characteristics can be reduced.

  In each of the above embodiments, the discharge side fluid resistance portion and the supply side fluid resistance portion may be three or more for one individual liquid chamber.

  Next, an example of an apparatus for ejecting liquid according to the present invention will be described with reference to FIGS. FIG. 18 is an explanatory plan view of the main part of the apparatus, and FIG. 19 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. 2 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. 21 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 the apparatus for ejecting liquid according to the present invention will be described with reference to FIGS. FIG. 22 is a schematic explanatory view of the apparatus, and FIG. 23 is a plan explanatory view of the 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 a plurality of liquid discharge heads (which are 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. 24 is an explanatory 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 the supply flow path side 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 on the discharge channel side 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 Diaphragm plate 4 Nozzle 5 Nozzle communication path 6 Individual liquid chamber 7, 7A, 7B Supply side fluid resistance part 8, 8A, 8B Supply side introduction part 10 Supply side common liquid chamber 11 Piezoelectric actuator 20 Common Liquid chamber member (frame member)
50 discharge side common liquid chamber 57, 57A, 57B discharge side fluid resistance part 58, 58A, 58B discharge side lead-out part 403 carriage 404 liquid discharge head 440 liquid discharge unit 630 liquid circulation system 1000 liquid discharge head

Claims (9)

A nozzle for discharging liquid;
An individual liquid chamber communicating with the nozzle;
A supply flow path for supplying the liquid in communication with the individual liquid chamber;
A discharge passage communicating with the individual liquid chamber and discharging the liquid, and
A liquid discharge head having at least two discharge-side fluid resistance portions constituting one discharge channel. 2. The liquid ejection head according to claim 1, wherein each of the two discharge-side fluid resistance portions is disposed in a different plane parallel to a plane on which the nozzle is formed. The liquid discharge head according to claim 1, wherein the two discharge-side fluid resistance portions are arranged in the same plane parallel to a plane on which the nozzle is formed. 4. The liquid discharge head according to claim 1, comprising at least two supply-side fluid resistance portions constituting one supply channel. 5. 5. The liquid ejection head according to claim 4, wherein each of the two supply-side fluid resistance units is disposed in a different plane parallel to the plane on which the nozzle is formed. 5. The liquid ejection head according to claim 4, wherein the two supply-side fluid resistance units are arranged in the same plane parallel to a plane on which the nozzle is formed.   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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