JP2020138331A - Liquid discharge head, liquid discharge unit, and liquid discharge device - Google Patents

Abstract

To cause a liquid in a nozzle to flow with a simple structure.SOLUTION: A liquid discharge head includes: a nozzle 4 which discharges a liquid; a pressure chamber 6 leading to the nozzle 4; an individual supply passage 7 leading to the pressure chamber 6; and an individual recovery passage 56 leading to the pressure chamber 6. At a side, which faces the pressure chamber 6, of a nozzle plate 1 formed with the nozzle 4, a recessed part 41 is provided near the nozzle 4. When the liquid is circulated, the liquid flows from the individual supply passage 7 to the individual recovery passage 56 along a surface of the nozzle plate 1 to generate turbulent flow 40 at the downstream side of the recessed part 41 and thereby flow the liquid in the nozzle 4.SELECTED DRAWING: Figure 2

Description

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

As the liquid discharge head, a pressure chamber circulation type head (flow-through type head) including an individual supply flow path and an individual recovery flow path communicating with the pressure chamber through which the nozzle communicates is known.

Conventionally, there is known a maintenance method in which the piezoelectric element is driven to vibrate the ink accumulated in the nozzle while circulating the ink in the individual flow path (pressure chamber) at the time of maintenance of the inkjet recording head (Patent Document). 1).

Japanese Patent No. 4617799

However, as disclosed in Patent Document 1, if the piezoelectric element that applies pressure to the pressure chamber is driven even during the maintenance cycle, there is a problem that the deterioration of the piezoelectric element is accelerated.

The present invention has been made in view of the above problems, and an object of the present invention is to allow the liquid in the nozzle to flow with a simple configuration.

In order to solve the above problems, the liquid discharge head according to the present invention is
A nozzle that discharges liquid and
The pressure chamber leading to the nozzle and
An individual supply flow path leading to the pressure chamber and
It is provided with an individual recovery flow path leading to the pressure chamber.
On the side of the nozzle plate on which the nozzle is formed facing the pressure chamber, a recess is provided in the vicinity of the nozzle.

According to the present invention, the liquid in the nozzle can be flowed with a simple structure.

It is sectional drawing which follows the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 1st Embodiment of this invention. Similarly, it is an enlarged cross-sectional explanatory view near the nozzle. It is a cross-sectional explanatory view of the main part along the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 2nd Embodiment of this invention. It is a perspective explanatory view of the vicinity of the nozzle of the liquid discharge head which concerns on 3rd Embodiment of this invention. It is also a plan explanatory view. It is sectional drawing of the recess along the nozzle arrangement direction corresponding to line AA of FIG. 1 of the liquid discharge head which concerns on 4th Embodiment of this invention. It is sectional drawing of the recess along the nozzle arrangement direction corresponding to line AA of FIG. 1 of the liquid discharge head which concerns on 5th Embodiment of this invention. It is sectional drawing which follows the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 6th Embodiment of this invention. It is the schematic explanatory drawing of an example of the apparatus which discharges a liquid which concerns on this invention. It is a plane explanatory view of an example of the head unit of this apparatus. It is a block explanatory drawing of an example of a liquid circulation device. It is a plane explanatory view of the main part of another example of the apparatus which discharges a liquid which concerns on this invention. It is explanatory drawing of the main part of the apparatus. It is a plane explanatory view of the main part of another example of the liquid discharge unit which concerns on this invention. It is a front explanatory view of still another example of the liquid discharge unit which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The first embodiment of the present invention will be described with reference to FIG. FIG. 1 is an explanatory cross-sectional view of a main part along a direction orthogonal to the nozzle arrangement direction of the liquid discharge head according to the same embodiment.

The liquid discharge head 100 has a nozzle plate 1, a flow path plate 2, and a diaphragm member 3 as a wall surface member laminated and joined. A piezoelectric actuator 11 that displaces the vibration region (diaphragm region, diaphragm) 30 of the diaphragm member 3 and a common flow path member 20 that also serves as a frame member are provided.

The nozzle plate 1 has a nozzle array in which nozzles 4 for discharging liquid are arranged. The plurality of nozzles 4 are arranged in the direction perpendicular to the paper surface.

The flow path plate 2 is a plurality of pressure chambers 6 leading to a plurality of nozzles 4, an individual supply flow path 7 serving as a fluid resistance unit communicating with each pressure chamber 6, and an intermediate supply flow path leading to one or a plurality of individual supply flow paths 7. The passage 8 and the individual recovery flow path 56 leading to each pressure chamber 6, or the intermediate recovery flow path 58 leading to one or a plurality of individual recovery flow paths 56 are formed.

A piezoelectric actuator 11 including a piezoelectric element is joined to the outside of the vibration region 30 of the diaphragm member 3 forming the wall surface of the pressure chamber 6.

The common flow path member 20 forms a common supply flow path 10 and a common recovery flow path 50. The common supply flow path 10 leads from the opening 9 of the diaphragm member 3 to the pressure chamber 6 via the intermediate supply flow path 8 and the individual supply flow path 7. The common recovery flow path 50 leads from the opening 59 of the diaphragm member 3 to the pressure chamber 6 via the intermediate recovery flow path 58 and the individual recovery flow path 56.

Further, the common supply flow path 10 is connected to an external circulation device via the supply port 71, and the common recovery flow path 50 is also connected to the external circulation device via the recovery port 72.

In the liquid discharge head 100, for example, the piezoelectric actuator 11 is driven to pull the vibration region 30 to expand the volume of the pressure chamber 6 and allow the liquid to flow into the pressure chamber 6. After that, the vibration region 30 is deformed in the direction toward the nozzle 4 by the piezoelectric actuator 11 to contract the volume of the pressure chamber 6, so that the liquid in the pressure 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 collected from the individual collection flow path 56 to the common collection flow path 50, and is again supplied from the common recovery flow path 50 to the common supply flow path 10 through an external circulation device. Nozzle. Further, even when the liquid is not discharged from the nozzle 4, the liquid is flowed from the common supply flow path 10 to the common recovery flow path 50 via the pressure chamber 6 by the circulation device, and is supplied to the common supply flow path 10 again. By doing so, the liquid is circulated.

Next, the structure in the vicinity of the nozzle 4 in the present embodiment will be described with reference to FIG. FIG. 2 is an enlarged cross-sectional explanatory view of the vicinity of the nozzle 4.

A recess 41 is provided in the vicinity of the liquid inflow side opening 4a of the nozzle 4 on the side of the nozzle plate 1 forming the nozzle 4 facing the pressure chamber 6.

Here, as described above, when the liquid is circulated without discharging the liquid, the liquid flows from the individual supply flow path 7 to the individual recovery flow path 56 via the pressure chamber 6. At this time, as shown in FIG. 2, assuming that the direction of the flow in the arrow direction along the surface of the nozzle plate 1 is the "direction of the liquid flow", the recess 41 is located upstream of the nozzle 4 in the liquid flow direction. It will be arranged.

Therefore, when the liquid circulates, the recess 41 generates a turbulent flow (vortex) 40 on the downstream side of the recess 41, that is, on the nozzle 4 side in the liquid flow direction. The turbulent flow 40 agitates and flows the liquid in the nozzle 4.

That is, the “near the nozzle” where the recess 41 is provided means that the liquid flowing into the pressure chamber 6 from the individual supply flow path 7 and flowing out from the pressure chamber 6 to the individual recovery flow path 56 causes the recess 41 to move to the nozzle 4 side. It may be a position where turbulence is generated. For example, the recess 41 may be arranged at any position between the connection portion between the individual supply flow path 7 and the pressure chamber 6 and the inflow side opening 4a of the nozzle 4.

As described above, the liquid in the nozzle 4 can be flowed by a simple configuration in which the recess 41 is provided in the nozzle 4, and the liquid in the nozzle 4 can be prevented from being deteriorated due to drying or the like.

Next, the second embodiment of the present invention will be described with reference to FIG. FIG. 3 is an explanatory cross-sectional view of a main part along a direction orthogonal to the nozzle arrangement direction of the liquid discharge head according to the same embodiment.

In the present embodiment, the recess 41 has a first wall portion 41b on the upstream side and a recess 41 that incline toward the bottom 41a of the recess 41 in a cross-sectional shape in a liquid flow direction, that is, a direction orthogonal to the nozzle arrangement direction. It has a second wall portion 41c on the downstream side that rises from the bottom portion 41a of the above at an angle larger than that of the first wall portion 41b.

Specifically, the recess 41 has a bending angle (bending angle of the first wall portion 41b with respect to the surface of the nozzle plate 1) on the upstream side in the liquid flow direction of less than 90 degrees with respect to the liquid flow direction. ..

As a result, the discontinuity with respect to the flow of the liquid from the surface of the nozzle plate 1 on the pressure chamber 6 side toward the surface of the first wall portion 41b is alleviated, and the generation of turbulent flow is suppressed. On the other hand, the effect of generating turbulence is enhanced at the second wall portion 41c of the recess 41 adjacent to the nozzle 4.

The bending angle of the first wall portion 41b of the recess 41 is set to less than 90 degrees, but the effect of generating turbulence is further enhanced by setting the bending angle to a smaller angle. Further, the first wall portion 41b of the recess 41 does not have to be a flat surface and may be a curved surface.

Next, the third embodiment of the present invention will be described with reference to FIGS. 4 and 5. FIG. 4 is a perspective explanatory view of the vicinity of the nozzle of the liquid discharge head according to the same embodiment, and FIG. 5 is a plan explanatory view.

In the present embodiment, the recess 41 has a planar shape in which the width in the direction along the nozzle arrangement direction gradually narrows toward the nozzle 4.

As a result, the flow velocity in the recess 41 increases toward the nozzle 4, and the effect of generating turbulence in the second wall portion 41c of the recess 41 increases.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a cross-sectional explanatory view of a recess along the nozzle arrangement direction corresponding to the line AA of FIG. 2 of the liquid discharge head according to the same embodiment.

In the present embodiment, the recess 41 has a curved bottom surface in a cross-sectional shape along the nozzle arrangement direction (a cross-sectional shape in a direction orthogonal to the direction from the recess 41 toward the liquid inflow side opening 4a of the nozzle 4), and here, a substantially arc. It has a shape.

As a result, the flow velocity in the vicinity of the recess 41 increases toward the center of the arc due to the effect of the Hagen-Poiseuille flow in the recess 41. Further, the deepest part of the arc of the recess 41 is aligned with or close to the center of the nozzle 4.

With such a configuration, the flow velocity of the liquid colliding with the second wall portion 41c of the recess 41 adjacent to the nozzle 4 is increased, and the turbulent flow generation effect is also enhanced.

Next, a fifth embodiment of the present invention will be described with reference to FIG. 7. FIG. 7 is a cross-sectional explanatory view of a recess along the nozzle arrangement direction corresponding to the line AA of FIG. 2 of the liquid discharge head according to the same embodiment.

In the present embodiment, the recess 41 has a cross-sectional shape along the nozzle arrangement direction (a cross-sectional shape in a direction orthogonal to the direction from the recess 41 toward the liquid inflow side opening 4a of the nozzle 4) from the bottom portion 41a to the surface of the nozzle plate 1. It has a shape with steps on all surfaces. As a result, the flow velocity near the recess 41 increases toward the deeper side of the bottom 41a.

Further, the bottom portion 41a of the recess 41 is aligned with or near the center of the nozzle 4.

With such a configuration, the flow velocity of the liquid colliding with the second wall portion 41c of the recess 41 adjacent to the nozzle 4 is increased, and the turbulent flow generation effect is also enhanced.

Next, the sixth embodiment of the present invention will be described with reference to FIG. FIG. 8 is an explanatory cross-sectional view taken along a direction orthogonal to the nozzle arrangement direction of the liquid discharge head according to the same embodiment.

In the present embodiment, the common supply flow path 10 and the common recovery flow path 50 are arranged on the same side with respect to the pressure chamber 6 in a direction orthogonal to the nozzle arrangement direction. Here, since the nozzle 4 is configured to communicate with the pressure chamber 6 via the nozzle communication passage 5, the individual recovery flow path 56 communicates with the pressure chamber 6 via the nozzle communication passage 5.

In the present embodiment, the flow path plate 2 is configured by laminating a plurality of plate-shaped members 2A to 2E, but the present invention is not limited to this. Further, the piezoelectric actuator 11 includes a columnar piezoelectric element 12 joined to the base member 13, and a flexible wiring member 15 is connected to the piezoelectric element 12.

A recess 41 is provided in the vicinity of the nozzle 4 on the side of the nozzle plate 1 facing the pressure chamber 6, that is, on the side facing the nozzle communication passage 5 in the present embodiment. The shape of the recess 41 may be the same as that of the second to fifth embodiments.

With such a configuration, the flow of the liquid from the nozzle communication passage 5 toward the individual collection flow path 56 along the nozzle plate 1 causes turbulence to occur on the downstream side due to the presence of the recess 41, and the turbulence is generated in the nozzle 4. The liquid flows.

Next, an example of the device for discharging the liquid according to the present invention will be described with reference to FIGS. 9 and 10. FIG. 9 is a schematic explanatory view of the device, and FIG. 10 is a plan explanatory view of an example of the head unit of the device.

The printing device 500, which is a device for discharging this liquid, includes a carry-in means 501 for carrying in the continuum 510, a guide transport means 503 for guiding and transporting the continuum 510 carried in from the carry-in means 501 to the printing means 505, and a continuous body. It includes a printing means 505 that discharges a liquid to 510 to form an image, a drying means 507 that dries the continuum 510, and a unloading means 509 that carries out the continuum 510.

The continuum 510 is sent out from the original winding roller 511 of the carrying-in means 501, guided and conveyed by the rollers of the carrying-in means 501, the guiding and transporting means 503, the drying means 507, and the carrying-out means 509, and is guided and conveyed by the winding roller 591 of the carrying-out means 509. It is wound up at.

The continuum 510 is conveyed in the printing means 505 facing the head unit 550 and the head unit 555, an image is formed by the liquid discharged from the head unit 550, and the processing liquid discharged from the head unit 555 is used later. Processing is done.

Here, the head unit 550 is provided with, for example, full-line head arrays 551A, 551B, 551C, and 551D for four colors from the upstream side in the transport direction (hereinafter, referred to as "head array 551" when colors are not distinguished). Is placed.

Each head array 551 is a liquid discharging means, and discharges black K, cyan C, magenta M, and yellow Y liquids to the conveyed continuum 510, respectively. The types and numbers of colors are not limited to this.

The head array 551 is, for example, in which the liquid discharge heads (which are also simply referred to as “heads”) 100 according to the present invention are arranged in a staggered pattern on the base member 552, but the head array 551 is not limited to this.

Next, an example of the liquid circulation device will be described with reference to FIG. FIG. 11 is a block explanatory view of the liquid circulation device. Although only one head is shown here, when a plurality of heads are arranged, the supply side liquid path and the recovery side liquid path are provided on the supply side and the recovery side of the plurality of heads via a manifold or the like, respectively. Will be connected.

The liquid circulation device 600 includes a supply tank 601, a recovery tank 602, a main tank 603, a first liquid feed pump 604, a second liquid feed pump 605, a compressor 611, a regulator 612, a vacuum pump 621, a regulator 622, and a supply side pressure sensor 631. , The recovery side pressure sensor 632 and the like.

Here, the compressor 611 and the vacuum pump 621 constitute means for generating a differential pressure between the pressure in the supply tank 601 and the pressure in the recovery tank 602.

The supply-side pressure sensor 631 is connected to the supply-side liquid path between the supply tank 601 and the head 100 and connected to the supply port 71 of the head 100. The recovery side pressure sensor 632 is connected between the head 1 and the recovery tank 602 to a recovery side liquid path connected to the recovery port 72 of the head 100.

One of the recovery tanks 602 is connected to the supply tank 601 via the first liquid feed pump 604, and the other of the recovery tank 602 is connected to the main tank 603 via the second liquid feed pump 605.

As a result, the liquid flows from the supply tank 601 through the supply port 71 into the head 100, is collected from the collection port 72 to the collection tank 602, and the liquid is collected from the collection tank 602 to the supply tank 601 by the first liquid feeding pump 604. By being sent, a circulation path through which the liquid circulates is constructed.

Here, a compressor 611 is connected to the supply tank 601 and is controlled so that a predetermined positive pressure is detected by the supply side pressure sensor 631. On the other hand, a vacuum pump 621 is connected to the recovery tank 602, and the recovery side pressure sensor 632 controls so that a predetermined negative pressure is detected.

As a result, the negative pressure of the meniscus can be kept constant while circulating the liquid through the head 100.

Further, when the liquid is discharged from the nozzle 4 of the head 100, the amount of liquid in the supply tank 601 and the recovery tank 602 decreases. Therefore, the liquid is replenished from the main tank 603 to the recovery tank 602 by using the second liquid feeding pump 605 as appropriate.

The timing of refilling the liquid from the main tank 603 to the recovery tank 602 is provided in the recovery tank 602, such as refilling the liquid when the liquid level height of the liquid in the recovery tank 602 falls below a predetermined height. It can be controlled by the detection result of the liquid level sensor or the like.

Next, another example of the printing device as a device for discharging the liquid according to the present invention will be described with reference to FIGS. 12 and 13. FIG. 12 is a plan view of the main part of the device, and FIG. 13 is a side view of the main part of the device.

The printing device 500 is a serial type device, and the carriage 403 is reciprocated 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 is bridged over the left and right side plates 491A and 491B to movably hold the carriage 403. Then, the carriage 403 is reciprocated in the main scanning direction by the main scanning motor 405 via the timing belt 408 bridged between the drive pulley 406 and the driven pulley 407.

The carriage 403 is equipped with a liquid discharge unit 440 in which the liquid discharge head 100 and the head tank 441 according to the present invention are integrated. The liquid discharge head 100 of the liquid discharge unit 440 discharges liquids of, for example, yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 100 is mounted by arranging a nozzle array composed of a plurality of nozzles in the sub-scanning direction orthogonal to the main scanning direction and directing the discharge direction downward.

The liquid discharge head 100 is connected to the liquid circulation device 600 described above, and a liquid of a required color is circulated and supplied.

The printing device 500 includes a transport mechanism 495 for transporting the paper 410. The transport mechanism 495 includes a transport belt 412, which is a transport means, and a sub-scanning motor 416 for driving the transport belt 412.

The transport belt 412 attracts the paper 410 and transports it at a position facing the liquid discharge head 100. The transport belt 412 is an endless belt, and is hung between the transport roller 413 and the tension roller 414. Adsorption can be performed by electrostatic adsorption, air suction, or the like.

Then, the transport belt 412 orbits in the sub-scanning direction by rotationally driving the transport roller 413 via the timing belt 417 and the timing pulley 418 by the sub-scanning motor 416.

Further, on one side of the carriage 403 in the main scanning direction, a maintenance / recovery mechanism 420 for maintaining / recovering the liquid discharge head 100 is arranged on the side of the transport belt 412.

The maintenance / recovery mechanism 420 is composed of, for example, a cap member 421 that caps the nozzle surface (the surface on which the nozzle is formed) of the liquid discharge head 100, a wiper member 422 that wipes the nozzle surface, and the like.

The main scanning movement mechanism 493, 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 the printing apparatus 500 configured in this way, the paper 410 is fed onto the transport belt 412 and sucked, and the paper 410 is conveyed in the sub-scanning direction by the circumferential movement of the transport belt 412.

Therefore, by driving the liquid discharge head 100 in response to the image signal while moving the carriage 403 in the main scanning direction, the liquid is discharged to the stopped paper 410 to form an image.

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

Among the members constituting the liquid discharge unit 440 and the device for discharging the liquid, a housing portion composed of side plates 491A, 491B and a back plate 491C, a main scanning moving mechanism 493, a carriage 403, and a liquid. It is composed of a discharge head 100.

A liquid discharge unit in which the above-mentioned maintenance / recovery mechanism 420 is further attached to, for example, the side plate 491B of the liquid discharge unit 440 can be configured.

Next, still another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 15 is a front explanatory view of the unit.

The liquid discharge unit 440 is composed of a liquid discharge head 100 to which the flow path component 444 is attached and a tube 456 connected to the flow path component 444.

The flow path component 444 is arranged inside the cover 442. A head tank 441 may be included instead of the flow path component 444. Further, a connector 443 that electrically connects to the liquid discharge head 100 is provided above the flow path component 444.

In the present application, the liquid to be discharged may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but the viscosity becomes 30 mPa · s or less at room temperature, under normal pressure, or by heating or cooling. It is preferable that it is a thing. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solvents, suspensions, emulsions, etc. containing edible materials such as natural dyes, etc., for example, inks for inkjets, surface treatment liquids, constituents of electronic elements and light emitting elements, and formation of electronic circuit resist patterns. It can be used for applications such as liquids for three-dimensional modeling.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electrothermal conversion elements such as heat-generating resistors, and electrostatic actuators that consist of a vibrating plate and counter electrodes are used as energy sources for discharging liquid. Includes what to do.

The "liquid discharge unit" is a liquid discharge head integrated with functional parts and a mechanism, and includes an aggregate of parts related to liquid discharge. For example, the "liquid discharge unit" includes a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, a main scanning movement mechanism, a liquid circulation device in which at least one of the configurations is combined with a liquid discharge head, and the like.

Here, "integration" means, for example, a liquid discharge head and a functional component, a mechanism in which the mechanism is fixed to each other by fastening, adhesion, engagement, etc., or one in which one is movably held with respect to the other. Including. Further, the liquid discharge head, the functional parts, and the mechanism may be detachably attached to each other.

For example, as a liquid discharge unit, there is a liquid discharge head and a head tank integrated. In addition, there are some that are connected to each other by a tube or the like to integrate the liquid discharge head and the head tank. Here, a unit including a filter can be added between the head tank of these liquid discharge units and the liquid discharge head.

Further, as a liquid discharge unit, there is a liquid discharge head and a carriage integrated.

Further, 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 by a guide member forming a part of the scanning movement mechanism. In some cases, the liquid discharge head, the carriage, and the main scanning movement mechanism are integrated.

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

Further, as a liquid discharge unit, there is a liquid discharge unit in which a tube is connected to a head tank or a liquid discharge head to which a flow path component is attached, and the liquid discharge head and a supply mechanism are integrated. The liquid of the liquid storage source is supplied to the liquid discharge head through this tube.

The main scanning movement mechanism shall also include a single guide member. Further, the supply mechanism includes a single tube and a single loading unit.

The "device for discharging a liquid" includes a device provided with a liquid discharge head or a liquid discharge unit and driving the liquid discharge head to discharge the liquid. The device for discharging the liquid includes not only a device capable of discharging the liquid to a device to which the liquid can adhere, but also a device for discharging the liquid into the air or the liquid.

The "device for discharging the liquid" can also include means for feeding, transporting, and discharging paper to which the liquid can adhere, and also includes a pretreatment device, a posttreatment device, and the like.

For example, as a "device that ejects a liquid", an image forming device that is a device that ejects ink to form an image on paper, and a powder is formed in layers in order to form a three-dimensional model (three-dimensional model). There is a three-dimensional modeling device (three-dimensional modeling device) that discharges the modeling liquid into the powder layer.

Further, the "device for discharging a liquid" is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. For example, those that form patterns that have no meaning in themselves and those that form a three-dimensional image are also included.

The above-mentioned "material to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as one that adheres and adheres, and one that adheres and permeates. Specific examples include media such as paper, recording paper, recording paper, film, cloth and other recording media, electronic substrates, electronic components such as piezoelectric elements, powder layers (powder layers), organ models, and inspection cells. Yes, including anything to which the liquid adheres, unless otherwise specified.

The material of the above-mentioned "material to which liquid can be attached" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can be attached even temporarily.

Further, the "device for discharging the liquid" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

In addition, as a "device for ejecting a liquid", a treatment liquid coating device for ejecting a treatment liquid to a paper in order to apply the treatment liquid to the surface of the paper for the purpose of modifying the surface of the paper, etc. There is an injection granulator that injects a composition liquid in which a raw material is dispersed in a solution through a nozzle to granulate fine particles of the raw material.

In addition, image formation, recording, printing, printing, printing, modeling, etc. in the terms of the present application are all synonymous.

1 Nozzle plate 4 Nozzle 2 Flow plate 3 Diaphragm member 6 Pressure chamber 7 Individual supply flow path 10 Common supply flow path 11 piezoelectric actuator 20 Common flow path member 41 Recess 50 Common recovery flow path 56 Individual recovery flow path 100 Liquid discharge head 403 Carriage 440 Liquid discharge unit 500 Printing device (device that discharges liquid)
550 head unit 600 liquid circulation device

Claims (8)

A nozzle that discharges liquid and
The pressure chamber leading to the nozzle and
An individual supply flow path leading to the pressure chamber and
It is provided with an individual recovery flow path leading to the pressure chamber.
A liquid discharge head characterized in that a recess is provided in the vicinity of the nozzle on the side of the nozzle plate on which the nozzle is formed facing the pressure chamber. The recess is characterized by having a first wall portion that is inclined or curved toward the bottom portion of the recess, and a second wall portion that rises from the bottom portion of the recess at an angle larger than that of the first wall portion. The liquid discharge head according to claim 1. The liquid discharge head according to claim 1 or 2, wherein the recess is gradually narrowed in width toward the liquid inflow side opening of the nozzle. The recess according to any one of claims 1 to 3, wherein the recess has an arcuate bottom surface in a cross-sectional shape in a direction orthogonal to the direction from the recess toward the liquid inflow side opening of the nozzle. Liquid discharge head. The recess according to any one of claims 1 to 3, wherein the recess has a cross-sectional shape in a direction orthogonal to the direction from the recess toward the liquid inflow side opening of the nozzle, and the bottom surface has a step. Liquid discharge head. A liquid discharge unit comprising the liquid discharge head according to any one of claims 1 to 5. A head tank that stores the liquid to be supplied to the liquid discharge head, a carriage on which the liquid discharge head is mounted, a supply mechanism that supplies the liquid to the liquid discharge head, a maintenance / recovery mechanism that maintains and recovers the liquid discharge head, and the liquid. The liquid discharge unit according to claim 6, wherein at least one of the main scanning moving mechanisms for moving the discharge head in the main scanning direction is integrated with the liquid discharge head. A device for discharging a liquid, which comprises the liquid discharge head according to any one of claims 1 to 5 or the liquid discharge unit according to claim 6 or 7.

Images