JP7016478B2 - Nozzle plate, liquid discharge head, liquid discharge unit, liquid discharge device - Google Patents

Description

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

As a liquid discharge head for discharging a liquid, there is a liquid discharge head provided with a nozzle plate having a nozzle hole formed as a nozzle by a pressing method.

Conventionally, when forming a nozzle hole by press working, it is known that by forming a dummy dot portion on the outer side of both ends of the nozzle row, deformation of the nozzle plate is suppressed and landing variation is reduced (patented). Document 1).

Japanese Unexamined Patent Publication No. 2014-07654

However, as disclosed in Patent Document 1, even if the nozzle plate has dummy dots on the outer sides of both ends of the nozzle row, there is a problem that the discharge characteristics vary due to the deformation in the direction orthogonal to the nozzle row. ..

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

In order to solve the above problems, according to the nozzle plate according to the present invention,
Multiple nozzles that discharge the discharged material are arranged,
The wall surface of the nozzle includes a straight portion from the discharge surface side, a tapered portion following the straight portion, and a sagging portion continuing from the tapered portion to the surface opposite to the discharge surface.
The width of the tapered portion in the nozzle arrangement direction is bx,
The width in the direction orthogonal to the nozzle arrangement direction of the tapered portion is by,
The width of the sagging portion in the nozzle arrangement direction is dx,
When the width in the direction orthogonal to the nozzle arrangement direction of the sagging portion is dy,
The configuration satisfies the relationship of 0 <by + dy <bx + dx in the direction orthogonal to the nozzle row arrangement direction.

According to the present invention, variations in discharge characteristics are reduced.

It is sectional drawing which follows the nozzle arrangement direction of the nozzle part of the nozzle plate which concerns on 1st Embodiment of this invention. Similarly, it is a cross-sectional explanatory view along the direction orthogonal to the nozzle arrangement direction. It is also a plan explanatory view. It is explanatory drawing which shows an example of the relationship between the sagging amount of the surface opposite to a discharge surface, and the deformation amount of a nozzle plate. It is sectional drawing explaining an example of the manufacturing method of the nozzle plate of the same embodiment. It is explanatory drawing explaining an example of the relationship with the sagging amount of a nozzle, the deformation amount of a nozzle plate, and the durability of a punch. It is sectional drawing explanatory drawing of the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 1st Embodiment of this invention. Similarly, it is a cross-sectional explanatory view in the nozzle arrangement direction corresponding to the X1-X1 line of FIG. It is sectional drawing explanatory drawing of the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 2nd Embodiment of this invention. It is a plane explanatory view of the main part of an example of the apparatus which discharges a liquid which concerns on this invention. It is explanatory drawing of the main part side surface 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. It is a schematic explanatory drawing of another example of the apparatus which discharges a liquid which concerns on this invention. It is a plane explanatory view of the head unit of this apparatus. It is a block explanatory drawing which provides the explanation of an example of the liquid circulation system in this apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, the nozzle plate according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional explanatory view of a nozzle portion of the nozzle plate along the nozzle arrangement direction, and FIG. 2 is a cross-sectional explanatory view along a direction orthogonal to the nozzle arrangement direction corresponding to X1-X1 of FIG.

The nozzle plate 1 has a plurality of nozzles 4 for discharging a discharged material, for example, a liquid. The discharged material is not limited to liquid, but may be gas, powder, or the like.

A flow path plate 2 forming an individual flow path 60, which is a flow path through which the plurality of nozzles 4 pass, is joined to the nozzle plate 1, and the individual flow paths 60 are separated by a partition wall 61.

Here, the wall surface of the nozzle 4 includes a tapered portion 4B that continues from the discharge surface 1a side to the straight portion 4A and the straight portion 4A, and a sagging portion 4C that continues from the tapered portion 4B to the surface 1b on the opposite side of the discharge surface 1a.

In this nozzle 4, the width of the tapered portion 4B in the nozzle arrangement direction is bx, the width of the tapered portion 4B in the direction orthogonal to the nozzle arrangement direction is by, and the width of the sagging portion 4C in the nozzle arrangement direction (hereinafter, also referred to as “sag amount”). ) Is dx, and the width in the direction orthogonal to the nozzle arrangement direction of the sagging portion 4C (hereinafter, also referred to as “sagging amount”) is dy.

Further, the width of the partition wall 61 between the flow paths 60 through which the plurality of nozzles 4 pass in the nozzle arrangement direction is a, the pitch between the nozzles 4 and 4 is c, and the radius of the nozzle 4 is r.

At this time, the nozzle 4 has a hole shape that satisfies the relationship of "0 <by + dy <bx + dx" in the direction orthogonal to the nozzle row arrangement direction.

Due to this relationship, when the nozzle 4 is formed by press working, the sagging amounts dx and dy of the sagging portion 4C are set to the conditions that the deformation amount of the nozzle plate 1 is small in the nozzle arrangement direction and the direction orthogonal to the nozzle arrangement direction. Can be done.

As a result, deformation of the nozzle plate 1 in both the nozzle arrangement direction and the direction orthogonal to the nozzle arrangement direction can be reduced.

This point will be described with reference to the explanatory diagram of FIG. 4, which shows an example of the relationship between the amount of sagging of the surface opposite to the discharge surface and the amount of deformation of the nozzle plate.

When the sagging amount dx in the nozzle arrangement direction is increased, the deformation amount of the nozzle plate in the nozzle arrangement direction becomes small, but the deformation amount in the direction orthogonal to the nozzle arrangement direction becomes large. On the other hand, when the sagging amount dx in the nozzle arrangement direction is reduced, the deformation amount of the nozzle plate in the direction orthogonal to the nozzle arrangement direction is small, but the deformation amount in the nozzle arrangement direction is large. This is because the influence of the deformation in one direction affects the deformation in the direction orthogonal to the one direction.

Therefore, in the present embodiment, by defining the sagging amount dx in the nozzle arrangement direction and the sagging amount dy in the direction orthogonal to the nozzle arrangement direction, both the nozzle plate in the nozzle arrangement direction and the direction orthogonal to the nozzle arrangement direction are deformed. Reduce the amount.

That is, when the nozzle is formed by pressing, when the sagging amount dx in the nozzle arrangement direction and the sagging amount dy in the direction orthogonal to the nozzle arrangement direction are the same, as shown in FIG. 4, the deformation amount in the nozzle arrangement direction ( The amount of deformation in the direction orthogonal to the condition a) or the nozzle arrangement direction (condition b) becomes large, or the amount of deformation in both becomes large (condition c).

Therefore, by setting "0 <by + dy <bx + dx", it is possible to manufacture the nozzle under the condition that the amount of sagging dx and dy are in the nozzle arrangement direction and the direction orthogonal to the nozzle arrangement direction, respectively, and the deformation amount of the nozzle plate is small. can. This makes it possible to suppress both the nozzle arrangement direction and the deformation in the direction orthogonal to the nozzle arrangement direction.

Further, in the present embodiment, the width of the partition wall 61 between the flow paths (individual flow paths 60) through which the plurality of nozzles 4 pass in the nozzle arrangement direction is a, the pitch between the nozzles 4 and 4 is c, and the radius of the nozzle 4. When is r, the relationship of 2 (bx + dx + r) ≦ ca in the nozzle row arrangement direction and 0 <by + dy <bx + dx in the direction orthogonal to the nozzle row arrangement direction are satisfied.

By satisfying the relationship of "2 (bx + dx + r) ≤ c-a", a sufficient joint region between the nozzle plate 1 and the individual flow path 60 can be sufficiently secured, and stable discharge becomes possible.

Further, by having the tapered portion 4B, Bx> 0, By> 0, and “0 <by + dy”.

Next, an example of a manufacturing method by press working of the nozzle plate will be described with reference to FIG. FIG. 5 is a cross-sectional explanatory view for the same explanation.

As shown in FIG. 5A, a nozzle base material 201 such as SUS (metal plate) to be the nozzle plate 1 is prepared.

Then, as shown in FIG. 5B, the nozzle base material 201 is set on the die 202 on the press working apparatus, and the punch 203 manufactured to a desired size is placed on the side opposite to the surface of the nozzle base material 201 to be the discharge surface. It is extruded vertically from the surface of the nozzle 203 toward the discharge surface side, and pressed until the tip of the punch 203 protrudes toward the discharge surface side of the nozzle base material 201. As a result, the convex portion 201a is formed on the nozzle base material 201.

Next, as shown in FIG. 5 (c), after the punch 203 is pulled up to remove the nozzle base material 201 from the press working device, the tape polishing device 204 is used to project the protrusion toward the discharge surface side of the nozzle base material 201. The portion 201a is polished and removed.

As a result, as shown in FIG. 5D, the nozzle 4 is opened, and the nozzle 4 is discharged from the straight portion 4A from the discharge surface 1a side, the tapered portion 4B following the straight portion 4A, and the tapered portion 4B on the wall surface of the nozzle 4. A nozzle plate 1 including a surface 1a and a sagging portion 4C following the surface 1b on the opposite side can be obtained.

Next, specific examples of the sagging amounts dx and dy of the nozzle 4 will be described with reference to FIG. FIG. 6 is an explanatory diagram illustrating an example of the relationship between the amount of sagging, the amount of deformation of the nozzle plate, and the durability of the punch.

When the nozzle 4 is formed by press working, the shorter the life of the punch 203, the higher the unit price of parts. In the press method, the life of the punch is affected by the springback of the material, that is, the clearance between the punch and the die, so it is necessary to set an appropriate clearance.

It is also known that there is a positive correlation between clearance and the amount of sagging. That is, in order to control the amount of sagging, the clearance may be controlled.

Here, according to FIG. 6, when the sagging amount dy <3 μm in the direction orthogonal to the nozzle arrangement direction, the durability of the punch is significantly deteriorated, and when the sagging amount dx ≧ 19 μm in the nozzle arrangement direction, the deformation amount is increased. The efficiency of reduction becomes worse.

Therefore, by setting 3 μm ≦ dy <19 μm and 19 μm <dx ≦ 27 μm, the life of the punch can be extended, and the amount of sagging can be reduced to reduce the amount of deformation of the nozzle plate.

Further, from FIG. 6, more preferably, the range is 3 μm ≦ dy ≦ 5 μm and 26 μm ≦ dx ≦ 27 μm, and by setting this range, the amount of deformation of the nozzle plate can be further reduced.

Even more preferably, by setting dy = 5 μm and dx = 26 μm, the life of the punch can be further extended, the reduction in the amount of sagging can be reduced, and the amount of deformation of the nozzle plate can be reduced.

Next, the liquid discharge head according to the first embodiment of the present invention will be described with reference to FIGS. 7 and 8. FIG. 7 is a cross-sectional explanatory view in a direction orthogonal to the nozzle arrangement direction of the liquid discharge head, and FIG. 7 is a cross-sectional explanatory view in the nozzle arrangement direction corresponding to the X1-X1 line of FIG.

In this liquid discharge head, the nozzle plate 1 according to the present invention, the flow path plate 2, and the diaphragm member 3 as a wall surface member are laminated and joined. Further, it includes a piezoelectric actuator 11 that displaces the vibration region (vibration plate) 30 of the diaphragm member 3, and a common liquid chamber member 20 that also serves as a frame member of the head.

The nozzle plate 1 has a plurality of nozzles 4 for discharging a liquid.

The flow path plate 2 forms an individual liquid chamber 6 that communicates with the nozzle 4 via the nozzle communication passage 5, a fluid resistance portion 7 that communicates with the individual liquid chamber 6, and a liquid introduction portion 8 that communicates with each fluid resistance portion 7. .. Here, the flow path plate 2 is configured by laminating three plate-shaped members 2A to 2C.

The diaphragm 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 3A forming a thin wall portion from the flow path plate 2 side and a second layer 3B forming a thick wall portion, and the first layer. A deformable vibration region 30 is formed in the portion corresponding to the individual liquid chamber 6 in the layer 3A.

Then, on the side of the diaphragm member 3 opposite to the individual liquid chamber 6, a piezoelectric actuator 11 including an electromechanical conversion element as a driving 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, for example, a required number of columnar piezoelectric elements 12A and 12B formed by groove processing the piezoelectric member joined to the base member 13 by half-cut dicing at predetermined intervals. The piezoelectric element 12A is joined to the convex portion 30a of the vibration region (vibration plate) 30 of the diaphragm member 3, and the piezoelectric element 12B to be a support column is joined to the convex portion 30b of the diaphragm member 3. Further, a flexible wiring member 15 is connected to the piezoelectric element 12.

The common liquid chamber member 20 forms the common liquid chamber 10. The common liquid chamber 10 is connected to a supply port 21 which is a supply port for supplying liquid from the outside.

The common liquid chamber 10 is connected to the liquid introduction unit 8 via the filter 9. The filter 9 is formed by the first layer of the diaphragm member 3.

In the liquid discharge head configured in this way, 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 vibrating plate member 3 is pulled to pull the individual liquid. As the volume of the chamber 6 expands, the liquid flows into the individual liquid chamber 6.

After that, 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 vibrating plate 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.

The method of driving the head is not limited to the above example (pull-push), and pulling or pushing may be performed depending on the driving waveform.

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

This liquid discharge head is an individual liquid chamber circulation type head, and the nozzle plate 1 according to the present invention, the flow path plate 2, and the diaphragm member 3 as a wall surface member are laminated and joined. Further, it includes a piezoelectric actuator 11 that displaces the vibration region (vibration plate) 30 of the diaphragm member 3, and a common liquid chamber member 20 that also serves as a frame member of the head.

The flow path plate 2 has an individual liquid chamber 6 through which the nozzle 4 communicates via the nozzle communication passage 5, a fluid resistance portion 7 on the supply side, and a liquid introduction, similar to the liquid discharge head of the first embodiment. It forms a part 8. Further, in the present embodiment, the flow path plate 2 forms an individual flow path 56 on the discharge side leading to the individual liquid chamber 6 via the nozzle communication passage 5, and a liquid lead-out portion 58. Here, the flow path plate 2 is configured by laminating four plate-shaped members 2A to 2C.

Further, the common liquid chamber member 20 forms a common liquid chamber 10 on the supply side and a common liquid chamber 50 on the discharge side. Liquid is supplied from the outside to the common liquid chamber 10 on the supply side through the supply port (supply port) 21, and the liquid is discharged to the outside through the discharge port (discharge port) 22 in the common liquid chamber 50 on the discharge side.

Further, a supply-side filter 9 is arranged between the supply-side common liquid chamber 10 and the liquid introduction unit 8, and a discharge-side filter 59 is arranged between the discharge-side common liquid chamber 50 and the liquid lead-out unit 58. is doing.

In this liquid discharge head, when the liquid is discharged, the liquid that is not discharged from the nozzle 4 passes through the nozzle 4 and passes through the individual flow path 56 on the discharge side to the liquid outlet 58 and the common liquid chamber 50 on the discharge side. Is discharged from the common liquid chamber 50 on the discharge side to the common liquid chamber 10 on the supply side again through an external circulation path.

Further, even when the liquid is not discharged, the liquid flows from the common liquid chamber 10 on the supply side to the common liquid chamber 50 on the discharge side via the individual liquid chamber 6, the individual flow path 56, and the like, and further through an external circulation path. It is supplied again to the common liquid chamber 10 on the supply side.

Next, an example of the device for discharging the liquid according to the present invention will be described with reference to FIGS. 10 and 11. FIG. 10 is an explanatory plan view of a main part of the device, and FIG. 11 is an explanatory view of a side surface of the main part of the device.

This device 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 according to the present invention, in which the liquid discharge head 404 and the head tank 441 according to the present invention are integrated. The liquid discharge head 404 of the liquid discharge unit 440 discharges, for example, liquids of each color of yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 404 is mounted by arranging a nozzle row composed of a plurality of nozzles in a sub-scanning direction orthogonal to the main scanning direction and facing the discharge direction 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 which is a filling part 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 delivered from the liquid cartridge 450 to the head tank 441 by the liquid feeding unit 452 via the tube 456.

This device 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 404. 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 404 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 404, a wiper member 422 that wipes 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 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 conveyor belt 412.

Therefore, by driving the liquid ejection head 404 in response to the image signal while moving the carriage 403 in the main scanning direction, the liquid is ejected onto the stopped paper 410 to form an image.

As described above, since this device includes the liquid discharge head according to the present invention, it is possible to stably form a high-quality image.

Next, another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 12 is an explanatory plan view of a main part of the unit.

This liquid discharge unit includes a housing portion composed of side plates 491A, 491B and a back plate 491C, a main scanning movement mechanism 493, a carriage 403, and a liquid among the members constituting the device for discharging the liquid. It is composed of a discharge head 404.

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

Next, still another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 13 is a front explanatory view of the unit.

This liquid discharge unit includes a liquid discharge head 404 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 404 is provided on the upper part of the flow path component 444.

Next, another example of the device for discharging the liquid according to the present invention will be described with reference to FIGS. 14 and 15. FIG. 14 is a schematic explanatory view of the device, and FIG. 15 is a plan view of the head unit of the device.

This device discharges liquid to the carry-in means 501 for carrying in the continuous medium 510, the guide-and-transport means 503 for guiding and transporting the continuous medium 510 carried in from the carry-in means 501 to the printing means 505, and the continuous medium 510. The printing means 505 for printing to form an image, the drying means 507 for drying the continuous medium 510, the discharging means 509 for discharging the continuous medium 510, and the like are provided.

The continuous medium 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 discharging means 509, and is guided and conveyed by the winding roller 591 of the discharging means 509. It is wound up at.

The continuous medium 510 is conveyed on the transfer guide member 559 in the printing means 505 facing the head unit 550 and the head unit 555, and an image is formed by the liquid discharged from the head unit 550 and discharged from the head unit 55. Post-treatment is performed with the treatment liquid to be treated.

Here, the head unit 550 is referred to, for example, as a full-line head array 551K, 551C, 551M, 551Y for four colors from the upstream side in the medium transport direction (hereinafter, when the colors are not distinguished, it is referred to as "head array 551". ) Is placed.

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

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

Next, an example of the liquid circulation system in this device will be described with reference to FIG. FIG. 16 is a block explanatory 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. It is composed of a pressure sensor 638, regulators (R) 639a, 639b and the like.

The supply-side pressure sensor 637 is connected to the supply-side flow path between the supply tank 631 and the head 1000 and connected to the supply port of the head 1000. The circulation side pressure sensor 638 is connected between the head 1000 and the circulation tank 632 to the discharge side flow path connected to the discharge port 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 tank 632 is connected to the main tank 602 via the second liquid feed pump 636.

As a result, the liquid flows from the supply tank 631 through the supply port 21 into the head 1000, is discharged from the discharge port 22, and is discharged to the circulation tank 632. Further, the liquid is circulated by being sent from the circulation tank 632 to the supply tank 631 by the first liquid feeding pump 635.

Further, a compressor 633 is connected to the supply tank 631, and the pressure sensor 637 on the supply side is controlled so that a predetermined positive pressure is detected. 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.

As a result, 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 as appropriate by using the second liquid feeding pump 636. The timing of liquid replenishment from the main tank 602 to the circulation tank 632 is such that the liquid level provided in the circulation tank 632 is replenished when the liquid level height in the circulation tank 632 drops 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 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 pigments, such as inks for inkjets, surface treatment liquids, components of electronic and light emitting elements, and formation of electronic circuit resist patterns. It can be used in applications such as liquids and material liquids for three-dimensional modeling.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electric heat 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 a collection 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 in which at least one of the configurations is combined with a liquid discharge head, and the like.

Here, the term "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, bonding, engagement, etc., or one in which one is movably held with respect to the other. include. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

For example, as a liquid discharge unit, there is a unit in which a liquid discharge head and a head tank are integrated. In some cases, 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 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 unit in which a liquid discharge head and a carriage are 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 constituting 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 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 a liquid includes not only a device capable of discharging a liquid to a device to which the liquid can adhere, but also a device for discharging the liquid into the air or into the liquid.

The "device for discharging the liquid" may include means for feeding, transporting, and discharging paper to which the liquid can adhere, as well as 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 three-dimensional object (three-dimensional object) are formed in layers in order to form a three-dimensional object. 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 "thing to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as a material to which the liquid adheres and adheres, and a material to which the liquid adheres and permeates. Specific examples include paper, recording paper, recording paper, film, recorded media such as cloth, electronic substrates, electronic components such as piezoelectric elements, powder layers (powder layers), organ models, and media such as inspection cells. Yes, and includes everything to which the liquid adheres, unless otherwise specified.

The material of the above-mentioned "material to which a liquid can adhere" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can adhere 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 the 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 granulation device that granulates fine particles of raw materials by injecting a composition liquid in which raw materials are dispersed in a solution through a nozzle.

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

1 Nozzle plate 2 Flow plate 3 Diaphragm member 4 Nozzle 5 Nozzle communication passage 6 Individual liquid chamber 7 Fluid resistance part 8 Liquid introduction part 9 Filter 10 Common liquid chamber (common liquid chamber on the supply side)
11 Piezoelectric actuator 20 Common liquid chamber member 50 Common liquid chamber (common liquid chamber on the discharge side)
58 Liquid outlet 59 Filter 403 Carriage 404 Liquid discharge head 440 Liquid discharge unit 630 Liquid circulation system 1000 Liquid discharge head

Claims (9)

Multiple nozzles that discharge the discharged material are arranged,
The wall surface of the nozzle includes a straight portion from the discharge surface side, a tapered portion following the straight portion, and a sagging portion continuing from the tapered portion to the surface opposite to the discharge surface.
The width of the tapered portion in the nozzle arrangement direction is bx,
The width in the direction orthogonal to the nozzle arrangement direction of the tapered portion is by,
The width of the sagging portion in the nozzle arrangement direction is dx,
When the width in the direction orthogonal to the nozzle arrangement direction of the sagging portion is dy,
A nozzle plate characterized in that the relationship of 0 <by + dy <bx + dx) is satisfied in a direction orthogonal to the nozzle row arrangement direction. The width of the partition wall between the flow paths through which the plurality of nozzles pass in the nozzle arrangement direction is a,
The pitch between the nozzles is c,
When the radius of the nozzle is r,
The nozzle plate according to claim 1, wherein the relationship of 2 (bx + dx + r) ≤ ca is satisfied in the nozzle row arrangement direction. The nozzle plate according to claim 1 or 2, wherein 3 μm ≦ dy <19 μm and 19 μm <dx ≦ 27 μm. The nozzle plate according to claim 3, wherein 3 μm ≦ dy ≦ 5 μm and 26 μm ≦ dx ≦ 27 μm. The nozzle plate according to claim 4, wherein dy = 5 μm and dx = 26 μm. The nozzle plate according to any one of claims 1 to 5 is included.
A liquid discharge head characterized by that. A liquid discharge unit comprising the liquid discharge head according to claim 6 . 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 7 , 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 claim 6 or the liquid discharge unit according to claim 7 or 8 .

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