Liquid ejection head, liquid ejection unit, and liquid ejection device

Abstract

To suppress inconveniences caused by a common liquid chamber resonating by liquid discharge from a plurality of nozzles.SOLUTION: A liquid discharge head 434 has: a plurality of nozzles 31 discharging liquid; a plurality of individual liquid chambers 22 communicating with each of the plurality of nozzles; a diaphragm composing wall parts of the plurality of individual liquid chambers; an actuator element driving the diaphragm; and a common liquid chamber 12 supplying the plurality of individual liquid chambers with the liquid. It has a resonance suppression part 14 for suppressing resonance of the common liquid chamber caused when the liquid is discharged by the plurality of nozzles.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection head, a liquid ejection unit, and an apparatus for ejecting liquid. [Background technology]

[0002] Conventionally, a liquid ejection head has been known that has a plurality of nozzles, a plurality of individual liquid chambers each connected to the plurality of nozzles, a vibration plate that forms the walls of the plurality of individual liquid chambers, an actuator element that drives the vibration plate, and a common liquid chamber that supplies liquid to the plurality of individual liquid chambers.

[0003] For example, Patent Document 1 discloses an inkjet recording head (liquid ejection head) in which a resistor (fluid resistance portion) that provides fluid resistance to ink is arranged in a common liquid chamber connected to each individual liquid chamber of two adjacent nozzles, so as to reduce the effects of undesired fluid interaction (crosstalk) between adjacent nozzles. Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional liquid ejection heads are unable to prevent problems such as a decrease in the ejection speed of liquid ejected from the nozzles due to resonance in the common liquid chamber caused by liquid ejection from a plurality of nozzles. [Means for solving the problem]

[0005] In order to solve the above problems, the present invention provides a liquid ejection nozzle. Nozzle plate on which and a plurality of individual liquid chambers respectively communicating with the plurality of nozzles. Flow path plate with a vibration plate that constitutes a wall portion of the plurality of individual liquid chambers; an actuator element that drives the vibration plate; and a common liquid chamber that supplies liquid to the plurality of individual liquid chambers. A frame formed a liquid ejection head having: Each vibration is propagated to the frame via the diaphragm. The common liquid chamber has a resonance suppression section for suppressing resonance of the common liquid chamber. The resonance suppression section is configured by a fluid resistance section that applies fluid resistance to the liquid in the common liquid chamber by narrowing the width direction of the common liquid chamber and narrowing the cross-sectional area of ​​the common liquid chamber using the shape of the partition wall section of the frame that forms the common liquid chamber. It is characterized by the following. [Effects of the Invention]

[0006] As described above, according to the present invention, it is possible to suppress problems caused by resonance in the common liquid chamber due to liquid ejection from a plurality of nozzles. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a cross-sectional view of the liquid ejection head according to the embodiment, taken along a plane perpendicular to the nozzle arrangement direction. [Figure 2] FIG. 2 is a cross-sectional view of the liquid ejection head taken along the nozzle arrangement direction. [Figure 3] FIG. 2 is a cross-sectional view taken along a plane parallel to the nozzle surface of the liquid ejection head. [Figure 4] FIG. 2 is a block diagram of an ink circulation system according to an embodiment. [Figure 5] FIG. 2 is an explanatory perspective view of the appearance of the liquid ejection head. [Figure 6] 10 is an explanatory diagram showing a liquid ejection head according to a conventional example, as viewed from the nozzle surface side. [Figure 7] FIG. 2 is an explanatory diagram schematically illustrating a liquid ejection head according to an embodiment, as viewed from the nozzle surface side. [Figure 8] FIG. 10 is an explanatory diagram showing a liquid ejection head according to a modified example, as viewed from the nozzle surface side. [Figure 9] FIG. 10 is an explanatory diagram schematically illustrating a liquid ejection head according to another modified example, as viewed from the nozzle surface side. [Figure 10] FIG. 10 is an explanatory diagram schematically illustrating a liquid ejection head according to yet another modified example, as viewed from the nozzle surface side. [Figure 11] FIG. 1 is an explanatory plan view of a main part of an example of a device for discharging liquid. [Figure 12] FIG. 2 is a side view illustrating a main part of the device for discharging liquid. [Figure 13] FIG. 10 is an explanatory plan view of a main part of another example of the liquid ejection unit. DETAILED DESCRIPTION OF THE INVENTION

[0008] An embodiment of a liquid ejection head according to the present invention will be described below. FIG. 1 is a cross-sectional view of an individual circulation type liquid ejection head 434 according to this embodiment, taken along a plane perpendicular to the nozzle arrangement direction. FIG. 2 is a cross-sectional view of the liquid ejection head 434 taken along the nozzle arrangement direction. FIG. 3 is a cross-sectional view taken along a plane parallel to the nozzle surface of the liquid ejection head 434. As shown in FIG.

[0009] The liquid ejection head 434 according to this embodiment is mainly composed of a frame 1 , a flow path plate 2 , a nozzle plate 3 , a base 4 , a laminated piezoelectric element 5 , and a vibration plate 6 .

[0010] The frame 1 is a component (partition member) in which are formed engravings that become ink supply ports 11 (see Figure 3) and common liquid chambers 12. The flow path plate 2 is a component in which are formed engravings that become pressure generating chambers 22, which are individual liquid chambers, and communication pipe portions 23 that communicate with nozzles 31. The nozzle plate 3 is a component in which the nozzles 31 are formed. The base 4 is a component that supports the laminated piezoelectric elements 5, which are pressure generating elements that serve as actuator elements. The vibration plate 6 is a component that has an island-shaped convex portion 61, a diaphragm portion 62, and an ink inlet 63.

[0011] The flow path plate 2 is formed with pressure generating chambers 22 that communicate with the nozzles 31, individual fluid resistance portions 21 that communicate with each pressure generating chamber 22, and introduction portions 20 that communicate with the individual fluid resistance portions 21. The flow path plate 2 is formed by stacking and bonding a plurality of (three in this case) plate-like members 2A, 2B, and 2C from the nozzle plate 3 side, and the flow path member 8 is formed by stacking and bonding these plate-like members 2A, 2B, and 2C and a vibration plate 6.

[0012] The nozzle plate 3 is made of a metal material, such as a Ni plating film formed by electroforming, and has a large number of nozzles 31, which are minute ejection openings for ejecting ink droplets. The internal shape (inner shape) of each nozzle 31 is formed in a horn shape (it may also be a roughly cylindrical shape or a roughly truncated cone shape). The diameter of each nozzle 31 on the ink droplet outlet side is approximately 20 μm to 35 μm. The nozzle pitch in each row is 150 dpi.

[0013] The ink ejection surface (nozzle surface side) of this nozzle plate 3 is provided with a water-repellent treatment layer 32, which has been subjected to a water-repellent surface treatment. The water-repellent treatment layer 32 is selected according to the ink properties, for example, by PTFE-Ni eutectoid plating, electrodeposition coating of fluororesin, vapor deposition coating of volatile fluororesin (such as fluorinated pitch), or baking after solvent application of silicone resin or fluororesin. This stabilizes the ink droplet shape and flight characteristics, enabling high-quality images to be obtained. The frame 1, which forms the ink supply port 11 and the carving that becomes the common liquid chamber 12, is made by resin molding.

[0014] The base 4 is a substrate that supports the multilayer piezoelectric element 5, and is made of, for example, SUS.

[0015] The multilayer piezoelectric element 5 has a laminated structure in which piezoelectric layers made of lead zirconate titanate (PZT) with a thickness of 10 μm to 50 μm per layer are alternately stacked with internal electrode layers made of silver-palladium (AgPd) with a thickness of several μm per layer. The internal electrode layers are connected to external electrodes at both ends. The multilayer piezoelectric element 5 is divided into comb-like pieces by half-cut dicing, and each piece is used as a driving part 56 and a support part 57 (non-driving part). The outer side of the external electrode is limited in length by notches or other processing so that it can be divided by half-cut dicing, and these become multiple individual electrodes 54. The other side is not divided by dicing and remains conductive, becoming a common electrode 55.

[0016] An FPC (flexible printed circuit) 13 is soldered to the individual electrodes 54 of the drive unit 56. The common electrode 55 is provided with an electrode layer at the end of the laminated piezoelectric element 5, and is routed around and joined to the ground electrode of the FPC 13. A head driver, which is a head control unit, is mounted on the FPC 13, and this controls the application of a drive voltage to the drive unit 56.

[0017] The diaphragm 6 is formed by stacking two layers of Ni-plated film using an electroforming method. The diaphragm 6 has a thin-film diaphragm portion 62, an island-shaped protrusion 61 formed in the center of the thin-film diaphragm portion 62 and bonded to the laminated piezoelectric element 5, which is the driving portion 56, a thick film portion including a beam bonded to the frame 1, and an opening that serves as the ink inlet 63. The diaphragm portion 62 is 3 μm thick and 35 μm wide (on one side). The island-shaped protrusion 61 of the diaphragm 6 and the movable portion (driving portion) 56 of the laminated piezoelectric element 5, as well as the diaphragm 6 and frame 1, are bonded by patterning an adhesive layer 7 made of an adhesive containing a gap material and bonding them together.

[0018] In the liquid ejection head 434 configured in this manner, a drive waveform (pulse voltage of 10 [V] to 50 [V]) composed of drive pulses is applied to the drive unit 56 in response to an image recording signal. This causes displacement in the stacking direction of the drive unit 56, pressurizing the pressure generating chamber 22 via the diaphragm 6, increasing the pressure, and ejecting ink droplets from the nozzles 31. Thereafter, as ink droplet ejection ends, the ink pressure in the pressure generating chambers 22 decreases, and negative pressure is generated in the pressure generating chambers 22 due to the inertia of the ink flow and the discharge process of the drive voltage (drive pulse), causing a transition to the ink filling process. At this time, ink supplied from the ink tank flows into the common liquid chamber 12, passes from the common liquid chamber 12 through the ink inlet 63, and passes through the individual fluid resistance units 21 to fill the pressure generating chambers 22.

[0019] While the individual fluid resistance section 21 is effective in damping residual pressure vibrations after ejection, it also acts as a resistance to refilling. By appropriately selecting the individual fluid resistance section 21, it is possible to achieve a balance between damping of residual pressure and refill time, thereby shortening the time (drive cycle) until the next ink droplet ejection operation.

[0020] Next, an example of an ink circulation system using the liquid ejection head 434 according to this embodiment will be described with reference to FIG. FIG. 4 is a block diagram of the ink circulation system according to this embodiment. As shown in FIG. 4, the ink circulation system is composed of a main tank 410, a liquid ejection head 434, a head tank 435, a supply-side pump 438a, a circulation-side pump 438b, a liquid feed pump 438c, a supply-side pressure sensor 439a, and a circulation-side pressure sensor 439b.

[0021] The supply-side pressure sensor 439a is located between the supply-side pump 438a and the liquid ejection head 434, and is connected to a supply flow path connected to a supply port 71 (see FIG. 1) of the liquid ejection head 434, which will be described later. The circulation-side pressure sensor 439b is located between the liquid ejection head 434 and the circulation-side pump 438b, and is connected to a circulation flow path connected to a circulation port 72 (see FIG. 1) of the liquid ejection head 434, which will be described later. The supply-side pump 438a and the circulation-side pump 438b cause ink to flow so that the supply-side pressure sensor 439a detects positive pressure and the circulation-side pressure sensor 439b detects negative pressure. This causes ink to circulate, flowing from the head tank 435 through the supply port 71 into the liquid ejection head 434, then being discharged from the circulation port 72 and returning to the head tank 435.

[0022] Furthermore, the supply-side pump 438a and the circulation-side pump 438b are constantly controlled so that the supply-side pressure sensor 439a maintains a constant positive pressure and the circulation-side pressure sensor 439b maintains a constant negative pressure. This allows the negative pressure of the meniscus to be maintained constant while circulating ink through the liquid ejection head 434. Furthermore, since the amount of ink in the head tank 435 decreases when droplets are ejected from the nozzles of the liquid ejection head 434, it is desirable to appropriately replenish ink from the main tank 410 to the head tank 435 using the liquid feed pump 438c. The timing of refilling the head tank 435 with ink from the main tank 410 can be controlled based on the detection results of a liquid level sensor or the like provided in the head tank 435, such as by refilling ink when the ink level in the head tank 435 drops below a predetermined level.

[0023] In this embodiment, a circulation flow path runs from the common liquid chamber 12 through the introduction section 20, the individual fluid resistance section 21, the pressure generating chamber 22, the communicating pipe section 23, and the circulation resistance section 42, and leads to a common circulation flow path 41. A nozzle 31 is disposed midway along the circulation flow path, at the end of the communicating pipe section 23. The common liquid chamber 12 is formed in the frame 1, and the flow path from the introduction section 20 to the circulation flow path 41 is formed in the flow path plate 2.

[0024] FIG. 5 is an explanatory perspective view of the appearance of a liquid ejection head 434 according to this embodiment. The supply port 71 of the frame 1 is disposed at the center of the common liquid chamber 12 in the nozzle arrangement direction, and is connected to the common liquid chamber 12. The circulation port 72 of the frame 1 is connected to the circulating liquid chamber 43 in the flow path plate 2. By disposing the supply port 71 at the center of the common liquid chamber 12 in the nozzle arrangement direction, the length of the liquid flow path from the supply port 71 to each circulation port 72 can be made the same for all pressure generating chambers 22. By making the flow path lengths the same in this way, the sum of the pressure loss generated in the common liquid chamber 12 and the pressure loss generated in the circulating liquid chamber 43 can be made the same for all paths passing through all pressure generating chambers 22. Furthermore, by making the sum of the pressure losses the same, it becomes possible to eliminate differences in characteristics due to pressure loss.

[0025] Generally, image forming devices such as printers, fax machines, copiers, plotters, and those combining multiple functions of these include inkjet recording devices equipped with a liquid ejection head that ejects ink droplets (hereinafter referred to as ink droplets). Inkjet recording devices form images by depositing ink droplets onto paper, a medium, using a liquid ejection head while the paper is being transported. Here, the term "medium" is sometimes referred to as "paper," but this does not limit the material; terms such as recording medium, recording medium, transfer material, and recording paper are also used interchangeably. Furthermore, an image forming device refers to a device that ejects droplets onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, or ceramics to form an image. Image formation refers not only to the application of meaningful images such as characters or figures to a medium, but also to the application of meaningless images such as patterns to a medium (simply ejecting droplets). Furthermore, the term "ink" is not limited to so-called ink, but is also used to refer to any liquid that forms droplets when ejected. It is used as a general term for liquids, including, for example, DNA samples, resists, and pattern materials.

[0026] FIG. 6 is an explanatory diagram showing a conventional liquid ejection head 434' as viewed from the nozzle surface side. The common liquid chamber 12 of the conventional liquid ejection head 434' shown in Figure 6 does not have a fluid resistance portion. More specifically, no fluid resistance portion is provided that can suppress the problem of resonance occurring in the common liquid chamber 12 when ink is ejected from a plurality of nozzles 31 (more nozzles, for example, all nozzles) in a specific frequency band (particularly a low frequency band), causing the ink ejection speed to drop below an allowable value. Resonance in the common liquid chamber 12 occurs when each vibration occurring when ink is ejected from all nozzles 31 in a specific low frequency band is transmitted to the common liquid chamber 12 via the vibration plate 6.

[0027] FIG. 7 is an explanatory diagram showing a schematic view of the liquid ejection head 434 according to this embodiment, as viewed from the nozzle surface side. The liquid ejection head 434 of this embodiment is provided with a resonance suppression section for suppressing resonance of the common liquid chamber 12 that occurs when ink is ejected from the multiple nozzles 31. The resonance suppression section of this embodiment is configured with a fluid resistance section 14 that applies fluid resistance to the ink in the common liquid chamber 12. The magnitude of the fluid resistance that this fluid resistance section 14 applies to the ink and its position within the common liquid chamber 12 are determined so that resonance of the common liquid chamber 12 that occurs when ink is ejected from all the nozzles 31 in a specific low frequency band in a conventional liquid ejection head 434 that does not have the fluid resistance section 14 formed therein is suppressed.

[0028] By providing such a fluid resistance portion 14 in the common liquid chamber 12, resonance of the common liquid chamber 12 is suppressed, and problems such as a decrease in ink ejection speed caused by resonance of the common liquid chamber can be suppressed. In other words, the fluid resistance portion 14 of this embodiment can suppress the above-mentioned problems that could not be suppressed by a conventional fluid resistance portion provided in the common liquid chamber to suppress crosstalk.

[0029] The fluid resistance portion 14 may be, for example, formed by attaching a member separate from the frame 1 that forms the common liquid chamber 12 to the wall surface of the common liquid chamber 12 to narrow the cross-sectional area of ​​the common liquid chamber 12. However, such a configuration in which a separate member is attached is difficult to fabricate in the process of fabricating the common liquid chamber, and requires a long processing time.

[0030] On the other hand, the fluid resistance portion 14 can be formed, for example, by a carved shape in the frame 1 that forms the common liquid chamber 12, so that the cross-sectional area of ​​the common liquid chamber 12 is narrowed. With this configuration, the fluid resistance portion 14 can be fabricated together with the common liquid chamber 12 during the fabrication process, making it easier to fabricate the common liquid chamber and reducing processing time.

[0031] 7, the fluid resistance portion 14 is provided in only one location in the common liquid chamber 12, but as shown in Fig. 8, the fluid resistance portion 14 may be provided in two or more locations in the common liquid chamber 12. Depending on the resonance that occurs in the common liquid chamber 12 of this liquid ejection head 434, providing fluid resistance portions 14 in multiple locations in the common liquid chamber 12 may be more effective in suppressing resonance in the common liquid chamber 12.

[0032] In addition, in the example shown in Figures 7 and 8, the cross-sectional area of ​​the common liquid chamber 12 is narrowed by narrowing the width of the common liquid chamber 12, but as shown in Figures 9 and 10, the cross-sectional area of ​​the common liquid chamber 12 may also be narrowed by narrowing the height of the common liquid chamber 12.

[0033] Next, an example of a liquid ejection device to which the liquid ejection heads 434 and 504 according to the embodiments can be applied will be described with reference to FIGS. 11 and 12, in which the liquid ejection head 504 is applied. FIG. 11 is an explanatory plan view of the main parts of the device for discharging liquid according to this embodiment, and FIG. 12 is an explanatory side view of the main parts of the device for discharging liquid according to this embodiment.

[0034] This liquid ejection device is a serial type device, and a carriage 503 is moved back and forth in the main scanning direction by a main scanning movement mechanism 593. The main scanning movement mechanism 593 is composed of a guide member 501, a main scanning motor 505, a timing belt 508, etc. The guide member 501 is hung between side plates 591A and 591B provided on both sides in the longitudinal direction of the device, and movably holds the carriage 503. The carriage 503 is moved back and forth in the main scanning direction, which is the longitudinal direction of the device, by the main scanning motor 505 via a timing belt 508 hung between a drive pulley 506 and a driven pulley 507.

[0035] The carriage 503 is provided with a liquid ejection unit 540 equipped with a liquid ejection head 504. The liquid ejection head 504 of the liquid ejection unit 540 ejects liquid of each color, for example, yellow (Y), cyan (C), magenta (M), and black (K). The liquid ejection head 504 is mounted with a nozzle row consisting of a plurality of nozzles arranged in a sub-scanning direction perpendicular to the main scanning direction, and the ejection direction facing downward. A supply and circulation mechanism 594 supplies liquid stored outside the liquid ejection head 504 to the liquid ejection head 504, and supplies and circulates the liquid within the liquid ejection head 504.

[0036] In this embodiment, the supply circulation mechanism 594 is composed of a supply tank 531, a circulation tank 532, a compressor 533, a vacuum pump 534, a first liquid feed pump 535, a second liquid feed pump 536, regulators (R) 539a and 539b, etc. The supply-side pressure sensor 537 is located between the supply tank 531 and the liquid ejection head 504, and is connected to the supply flow path connected to the supply port 71 of the liquid ejection head 504. The circulation-side pressure sensor 538 is located between the liquid ejection head 504 and the circulation tank 532, and is connected to the circulation flow path connected to the circulation port 72 of the liquid ejection head 504.

[0037] The liquid ejection device is equipped with a transport mechanism 595 for transporting paper 510. The transport mechanism 595 is composed of a transport belt 512, which is a transport means, and a sub-scanning motor 516 for driving the transport belt 512. The transport belt 512 attracts the paper 510 and transports it to a position facing the liquid ejection head 504. The transport belt 512 is an endless belt that is stretched between a transport roller 513 and a tension roller 514. The paper 510 can be attracted to the transport belt 512 by electrostatic attraction or air suction. The transport belt 512 moves in a circular motion in the sub-scanning direction as the transport roller 513 is rotated and driven by the sub-scanning motor 516 via a timing belt 517 and a timing pulley 518.

[0038] A maintenance and recovery mechanism 520 that maintains and recovers the liquid ejection head 504 is disposed on one side of the carriage 503 in the main scanning direction, beside the conveyor belt 512. The maintenance and recovery mechanism 520 is composed of, for example, a cap member 521 that caps the nozzle surface (the surface on which the nozzles are formed) of the liquid ejection head 504, a wiper member 522 that wipes the nozzle surface, and the like.

[0039] The main scanning movement mechanism 593, supply circulation mechanism 594, maintenance recovery mechanism 520, and transport mechanism 595 are attached to a housing formed by side plates 591A and 591B, a back plate 591C, etc. In a liquid ejecting device configured in this manner, a sheet of paper 510 is fed onto and adsorbed to a conveyor belt 512, and the sheet of paper 510 is transported in the sub-scanning direction by the circular movement of the conveyor belt 512. Then, by driving the liquid ejection head 504 in accordance with an image signal while moving the carriage 503 in the main scanning direction, liquid is ejected onto the stationary sheet of paper 510, thereby forming an image. In this way, the liquid ejection device, equipped with the liquid ejection head 504, can stably form high-quality images.

[0040] Next, another example of the liquid discharge unit 540 will be described with reference to FIG. FIG. 13 is an explanatory plan view of the main part of the unit. Of the components that make up the device that ejects the liquid, this liquid ejection unit 540 is made up of a housing portion made up of side plates 591A and 591B and a back plate 591C, a main scanning movement mechanism 593, a carriage 503, and a liquid ejection head 504. It is also possible to configure this liquid ejection unit 540 by further attaching at least one of the maintenance and recovery mechanism 520 and the supply and circulation mechanism 594 described above to, for example, side plate 591B of this liquid ejection unit 540.

[0041] In this embodiment, a "liquid ejection head" refers to a functional component that ejects and sprays liquid from nozzles. The ejected liquid may have a viscosity and surface tension that allows it to be ejected from the head. While not particularly limited, it is preferable that the viscosity of the ejected liquid be 30 mPa·s or less at room temperature and pressure, or upon heating or cooling. More specifically, the liquid may be a solution, suspension, emulsion, or the like containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a polymerizable compound, a resin, a surfactant, or the like, a biocompatible material such as DNA, amino acids, proteins, or calcium, or an edible material such as a natural dye. These liquids can be used, for example, as inkjet inks, surface treatment solutions, liquids for forming components of electronic elements or light-emitting elements, or resist patterns for electronic circuits, and liquid materials for three-dimensional modeling. Energy sources for ejecting the liquid include piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators using electrothermal conversion elements such as heating resistors, and electrostatic actuators consisting of a diaphragm and an opposing electrode.

[0042] A "liquid ejection unit" is a collection of components related to liquid ejection, in which functional components and mechanisms are integrated with a liquid ejection head. For example, a "liquid ejection unit" includes a combination of a liquid ejection head and at least one of a supply / circulation mechanism, a carriage, a maintenance / recovery mechanism, and a main scanning movement mechanism. Here, "integration" includes, for example, a combination in which the liquid ejection head and functional components or mechanisms are fixed to each other by fastening, bonding, engaging, or the like, or a combination in which one is held movably relative to the other. The liquid ejection head, functional components, and mechanisms may also be configured to be detachable from each other.

[0043] For example, some liquid ejection units integrate a liquid ejection head and a supply / circulation mechanism. Others integrate the liquid ejection head and the supply / circulation mechanism by connecting them with a tube or the like. A filter unit can be added between the supply / circulation mechanism and the liquid ejection head of these liquid ejection units. Other liquid ejection units integrate a liquid ejection head and a carriage. Other liquid ejection units integrate a liquid ejection head and a scanning movement mechanism by movably holding the liquid ejection head on a guide member that constitutes part of a scanning movement mechanism. Other liquid ejection units integrate a liquid ejection head, carriage, and maintenance / recovery mechanism by fixing a cap member, which is part of a maintenance / recovery mechanism, to a carriage to which the liquid ejection head is attached. Other liquid ejection units integrate a liquid ejection head and a supply mechanism by connecting a tube to a liquid ejection head to which a supply / circulation mechanism or a flow path component is attached. Liquid from a liquid storage source is supplied to the liquid ejection head via this tube. The main scanning movement mechanism also includes the guide member alone. The supply mechanism also includes the tube alone and the loading unit alone.

[0044] A "liquid ejecting device" is a device that has a liquid ejection head or a liquid ejection unit and ejects liquid by driving the liquid ejection head. Liquid ejecting devices include not only devices that can eject liquid onto objects onto which the liquid can adhere, but also devices that eject liquid into air or liquid. This "liquid ejecting device" can also include means for feeding, transporting, and discharging objects onto which the liquid can adhere, as well as pre-processing devices and post-processing devices.

[0045] For example, "liquid ejecting devices" include image forming devices that eject ink to form an image on paper, and three-dimensional modeling devices (three-dimensional modeling devices) that eject modeling liquid onto a powder layer formed by forming a powder in a layered form in order to form a three-dimensional object (a three-dimensional model). Furthermore, "liquid ejecting devices" are not limited to devices that visualize meaningful images such as letters and figures using the ejected liquid. For example, they also include devices that form patterns that have no meaning in themselves, and devices that form three-dimensional images.

[0046] The above-mentioned "substances to which a liquid can adhere" refers to substances to which a liquid can adhere at least temporarily, such as substances to which the liquid can adhere and stick, or substances to which the liquid can adhere and penetrate. Specific examples include media such as paper, recording paper, film, and cloth, electronic substrates, electronic components such as piezoelectric elements, powder layers, organ models, and test cells, and unless otherwise specified, includes all substances to which a liquid can adhere. The above-mentioned "substances to which a liquid can adhere" may be any material to which a liquid can adhere, such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, or ceramics, as long as the liquid can adhere even temporarily.

[0047] The "liquid" may be any liquid having a viscosity and surface tension that allows it to be ejected from a head, but is not particularly limited thereto. Preferably, the viscosity of the liquid is 30 mPa·s or less at room temperature and pressure, or upon heating or cooling. More specifically, the liquid may be a solution, suspension, emulsion, or the like containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a polymerizable compound, a resin, a surfactant, or other functional material, a biocompatible material such as DNA, amino acids, proteins, or calcium, or an edible material such as a natural dye. These liquids can be used, for example, in inkjet inks, surface treatment solutions, liquids for forming components of electronic devices or light-emitting elements, or resist patterns for electronic circuits, and liquid materials for 3D modeling.

[0048] Furthermore, the term "liquid ejecting device" includes, but is not limited to, a device in which a liquid ejection head and an object onto which the liquid can be attached move relatively. Specific examples include a serial-type device in which the liquid ejection head moves, and a line-type device in which the liquid ejection head does not move. Other examples of "liquid ejecting device" include a treatment liquid application device that ejects a treatment liquid onto paper to apply the treatment liquid to the surface of the paper for purposes such as modifying the surface of the paper. Another example is an injection granulation device that sprays a composition liquid in which raw materials are dispersed through a nozzle to granulate fine particles of the raw materials. In addition, the terms "image formation," "recording," "printing," "imaging," "printing," "shaping," and the like in this application are all synonymous.

[0049] The above description is merely an example, and each of the following aspects provides unique effects. [First aspect] The first aspect is a liquid ejection head 434 having a plurality of nozzles 31 that eject liquid (e.g., ink), a plurality of individual liquid chambers (e.g., pressure generating chambers 22) that are respectively connected to the plurality of nozzles, a vibration plate 6 that forms the walls of the plurality of individual liquid chambers, an actuator element (e.g., a laminated piezoelectric element 5) that drives the vibration plate, and a common liquid chamber 12 that supplies liquid to the plurality of individual liquid chambers, and is characterized by having a resonance suppression section (e.g., a fluid resistance section 14) that suppresses resonance of the common liquid chamber that occurs when liquid is ejected from the plurality of nozzles. The inventors have found that even in a configuration that can suppress crosstalk caused by vibrations occurring in the liquid in individual liquid chambers propagating through the liquid to the liquid in the common liquid chamber when liquid is ejected from multiple nozzles, problems such as a decrease in the ejection speed of the liquid ejected from the nozzles occur. This is thought to be because the vibrations occurring when liquid is ejected from multiple nozzles propagate to the common liquid chamber through the vibration plates that form the walls of each individual liquid chamber, causing the common liquid chamber to resonate, resulting in the above-mentioned problems. Therefore, in this embodiment, a resonance suppression section is provided to suppress resonance in the common liquid chamber that occurs when liquid is ejected from multiple nozzles, thereby suppressing resonance in the common liquid chamber when liquid is ejected from multiple nozzles, and making it possible to suppress problems caused by resonance in the common liquid chamber that could not be suppressed by conventional fluid resistance sections provided in the common liquid chamber to suppress crosstalk.

[0050] [Second mode] A second aspect is the first aspect, characterized in that the resonance suppression portion is configured by a fluid resistance portion 14 that applies fluid resistance to the liquid in the common liquid chamber. According to this aspect, a fluid resistance portion is used as a resonance suppressor, and resonance in the common liquid chamber that occurs when liquid is ejected from multiple nozzles is suppressed by the fluid resistance portion providing fluid resistance to the liquid in the common liquid chamber. Because such a fluid resistance portion can be manufactured relatively easily, it is possible to provide a low-cost liquid ejection head.

[0051] [Third aspect] A third aspect is the second aspect, characterized in that the fluid resistance portions are arranged at a plurality of locations in the common liquid chamber. Depending on the type of resonance that occurs in the common liquid chamber, providing fluid resistance portions at multiple locations in the common liquid chamber may be more effective in suppressing resonance in the common liquid chamber. In such cases, this aspect makes it possible to effectively suppress resonance in the common liquid chamber.

[0052] [Fourth aspect] The fourth aspect is characterized in that, in the second or third aspect, the fluid resistance portion is formed by narrowing the cross-sectional area of ​​the common liquid chamber by the shape of a partition portion (e.g., frame 1) that forms the common liquid chamber. According to this aspect, the fluid resistance portion can be fabricated in the process of fabricating the common liquid chamber, so that a low-cost liquid ejection head can be provided.

[0053] [Fifth mode] The fifth aspect is characterized in that, in the second or third aspect, the fluid resistance portion is formed by providing a separate member on a partition portion (e.g., frame 1) that forms the common liquid chamber, thereby narrowing the cross-sectional area of ​​the common liquid chamber. According to this aspect, it is possible to provide the fluid resistance portion without making any changes to the existing manufacturing process of the common liquid chamber.

[0054] [Sixth aspect] A sixth aspect is the fourth or fifth aspect, characterized in that the fluid resistance portion is formed by narrowing the common liquid chamber in the height direction. Depending on the type of resonance occurring in the common liquid chamber, there are cases in which narrowing the height of the common liquid chamber to provide fluid resistance can be more effective in suppressing resonance in the common liquid chamber. In such cases, according to this aspect, resonance in the common liquid chamber can be effectively suppressed.

[0055] [Seventh aspect] The seventh aspect is a liquid ejection unit comprising at least one of the head tank, carriage, supply mechanism, maintenance and recovery mechanism, and main scanning movement mechanism aspects, and a liquid ejection head, wherein the liquid ejection head is any of the liquid ejection heads of the first to sixth aspects. This makes it possible to suppress problems in the liquid ejection unit caused by resonance in the common liquid chamber of the liquid ejection head.

[0056] [Eighth aspect] An eighth aspect is a liquid ejection device characterized by having the liquid ejection head of any one of the first to sixth aspects or the liquid ejection unit of the seventh aspect. This makes it possible to suppress problems caused by resonance in the common liquid chamber of the liquid ejection head in a liquid ejection device. [Explanation of symbols]

[0057] 1: Frame 2: Flow path plate 3: Nozzle plate 4: Bass 5: Multilayer piezoelectric element 6: Vibration plate 7: Adhesive layer 8: Flow path member 9: Actuator member 11: Ink supply port 12: Common liquid chamber 13: FPC 14: Fluid resistance section 20: Introduction 21: Individual fluid resistance section 22: Pressure generating chamber 23:Communication pipe section 31: Nozzle 32: Water-repellent layer 41: Circulation flow path 42: Circulation resistance section 43: Circulating fluid chamber 54: Individual electrode 55: Common electrode 56: Drive unit 57: Support part 61: Island-shaped convex part 62: Diaphragm part 63: Ink inlet 71: Supply port 72: Circulation port 101: Scale 101a: Reference scale 102: Scale 102a: Reference scale 103:Reference mark 410: Main tank 434: Liquid ejection head 435: Head Tank 438a: Supply pump 438b: Circulation side pump 438c: Liquid transfer pump 439a: Supply side pressure sensor 439b: Circulation side pressure sensor 501: Guide member 503: Carriage 504: Liquid ejection head 505: Main scanning motor 506: Drive pulley 507: Driven pulley 508: Timing belt 510: Paper 512: Conveyor belt 513: Transport roller 514: Tension roller 516: Sub-scanning motor 517: Timing belt 518: Timing pulley 520: Maintenance and Recovery Mechanism 521: Cap member 522: Wiper member 531: Supply Tank 532: Circulation tank 533: Compressor 534: Vacuum pump 535: First liquid transfer pump 536: Second liquid transfer pump 537: Supply side pressure sensor 538: Circulation side pressure sensor 540: Liquid discharge unit 591A: Side plate 591B: Side plate 591C: Back plate 593: Main scanning movement mechanism 594: Supply circulation mechanism 595:Transport mechanism [Prior art documents] [Patent documents]

[0058] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-132080

Claims

1. a nozzle plate in which a plurality of nozzles for ejecting liquid are formed; a flow path plate having a plurality of individual liquid chambers formed therein, each of which communicates with the plurality of nozzles; a vibration plate that forms a wall portion of the plurality of individual liquid chambers; an actuator element that drives the diaphragm; a frame in which a common liquid chamber is formed to supply liquid to the plurality of individual liquid chambers, a resonance suppression section for suppressing resonance in the common liquid chamber that occurs when vibrations caused when liquid is ejected from the plurality of nozzles are transmitted to the frame via the vibration plate, A liquid ejection head characterized in that the resonance suppression portion is composed of a fluid resistance portion that applies fluid resistance to the liquid in the common liquid chamber by narrowing the width direction of the common liquid chamber and narrowing the cross-sectional area of ​​the common liquid chamber through the shape of the partition portion of the frame that forms the common liquid chamber.

2. In the liquid ejection head according to claim 1, The liquid ejection head is characterized in that the fluid resistance portions are arranged at a plurality of locations in the common liquid chamber.

3. A liquid ejection unit comprising at least one of a head tank, a carriage, a supply mechanism, a maintenance and recovery mechanism, and a main scanning movement mechanism, and a liquid ejection head, 3. A liquid ejection unit, comprising the liquid ejection head according to claim 1 or 2 as the liquid ejection head.

4. In a device for discharging a liquid, 4. A liquid ejection device comprising: a liquid ejection head according to claim 1 or 2; or a liquid ejection unit according to claim 3.

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