JP2004358872A - Ink jet recording head and ink jet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To homogenize discharging characteristics of each ejector of an ejector group having ejectors disposed in a matrix state. <P>SOLUTION: This ink jet recording head includes dummy holes 60 formed on the outer periphery of the ejector group 52, and, accordingly, the amounts of excess adhesives protruding into a pressure chamber 12 are the same, and is not influenced by variation in size occurring in etching process. The shape of the pressure chamber 12 having large influence to the discharging characteristics of ink droplet has all substantially the same shape in each ejector 50, and the supporting rigidity of each ejector 50 is substantially equal. Thus, since the shape of the pressure chamber 12 of each ejector 50 and the supporting rigidity of the ejector 50 are substantially equal, the discharging characteristics of each ejector 50 of the ejector group 52 are uniformed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an inkjet recording head and an inkjet recording device.
[0002]
[Prior art]
The ink jet recording apparatus records characters and images on the recording paper by reciprocating the ink jet recording head in the main scanning direction and conveying the recording paper in the sub scanning direction, and selectively ejecting ink droplets from a plurality of nozzles. . The ink jet recording head ejects ink droplets from nozzles communicating with the pressure chambers by pressurizing the ink in the pressure chambers via a diaphragm using an actuator, for example, a piezoelectric element that converts electrical energy into mechanical energy. Methods are known.
[0003]
By the way, in recent years, the tendency of an ink jet recording apparatus to increase in speed is increasing. Therefore, by increasing the length of the ink jet recording head and increasing the number of nozzles per ink jet recording head and arranging them in a matrix, an ink jet recording head capable of forming an image in a wide area in a shorter time is produced. Have been.
[0004]
In addition, the present applicant forms an ejector group in which ejectors each including a nozzle, a pressure chamber, an actuator, an ink supply path, and the like are arranged in a matrix, and, in an inkjet recording head having one or a plurality of ejector groups, An ink jet recording head has been proposed in which each plate in which holes serving as pressure chambers and ink flow paths are formed by etching is bonded and bonded. (See, for example, Patent Documents 1 and 2)
In addition, in an ink jet recording head manufactured by adhesively bonding a plurality of plates and in which nozzles are arranged in a line, the adhesive bleeds into the nozzle grooves to prevent a decrease in ink ejection performance, so that the gap between the nozzle grooves is reduced. A configuration has been proposed in which a groove for releasing an adhesive is formed. (For example, see Patent Document 3)
[0005]
[Patent Document 1]
JP 2001-334661 A [Patent Document 2]
JP 2003-048323 A [Patent Document 3]
JP 05-330067 A [0006]
[Problems to be solved by the invention]
Now, as described in JP-A-2001-334661 and JP-A-2003-048323, the inkjet recording head 312 shown in FIG. 10 was manufactured and various evaluations were performed. As a result, the outer edge of the ejector group 252 was formed. It has been discovered that the ejector 250 arranged and the ejector 250 arranged other than at the outer edge have slightly different ink droplet ejection characteristics.
[0007]
As a result of analyzing the phenomenon that the ejection characteristics of the ink droplets are slightly different, the applicant has found the following causes (1) to (3).
[0008]
(1) As shown in FIG. 10 (A), when each plate is bonded and manufactured, the adhesive 270 comes out into the pressure chamber 212, and the shape of the pressure chamber 212 slightly changes.
[0009]
Now, the pressure chambers 212 other than the outer edge portion of the ejector group 252 have eight adjacent pressure chambers 212 around the entire circumference. Become. For this reason, the amount of the adhesive 270 that comes out of the pressure chamber 212 during bonding is small and the amount of the adhesive 270 that comes out of the pressure chamber 212 is the same, so that the shape of the pressure chamber 212 is also the same. (See B1 in FIG. 10A)
On the other hand, since the pressure chamber 212 does not exist in the entire periphery of the pressure chamber 212 at the outer edge portion, the margin of the periphery where the adhesive 270 is applied increases. Therefore, the amount of the adhesive 270 that sticks out to the pressure chamber 212 at the time of bonding increases. (See B2 in FIG. 10A)
That is, as shown by B1 and B2 in FIG. 10A, the pressure chamber 212 other than the outer edge is different from the outer edge pressure chamber 212 in the amount of adhesive to be removed.
[0010]
Accordingly, since the shape of the pressure chamber 212 other than the outer edge of the ejector group 252 and the shape of the pressure chamber 212 at the outer edge differ depending on the difference in the amount of the adhesive to be discharged, the ejection characteristics of the ink droplets differ.
[0011]
Note that the same can be said for the ink communication chamber 216, the ink supply path 218, and the like as well as the pressure chamber 212.
[0012]
(2) When drilling a hole that becomes, for example, the pressure chamber 212 of each of the ejectors 250 arranged in a matrix, the outer hole, particularly the outermost hole, that is, the outer edge of the ejector group 252 in processing, particularly, in the etching process. In the hole serving as the pressure chamber 212 of the ejector 250, the edging liquid easily accumulates and the hole becomes large.
[0013]
Therefore, the shape of the ejector 250 other than the outer edge and the shape of the ejector 250 at the outer edge are different, and the ejection characteristics of the ink droplets are different.
[0014]
(3) As described in the above (1), the ejectors 250 other than the outer edge of the ejector group 252 have eight adjacent ejectors 250 around the entire periphery, but the ejectors 250 other than the outer edge have the entire periphery. Ejector 250 is not present. Therefore, the support area around each ejector 250 (the same as the bonding allowance) is different.
[0015]
Therefore, since the support rigidity of the ejector 250 other than the outer edge of the ejector group 252 and the ejector 250 at the outer edge is different, the ejection characteristics of the ink droplets are different.
[0016]
As described above, due to the causes (1) to (3), the ejector 250 arranged at the outer edge of the ejector group 252 in which the ejectors 250 are arranged in a matrix and the ejector 250 arranged other than the outer edge are different. There is a difference in the ejection characteristics.
[0017]
SUMMARY OF THE INVENTION The present invention has been made to solve the above problem, and has as its object to make the ejection characteristics of each ejector of an ejector group in which the ejectors are arranged in a matrix uniform.
[0018]
[Means for Solving the Problems]
The ink jet recording head according to claim 1, wherein at least a pressure chamber, a nozzle communicating with the pressure chamber and ejecting ink droplets, and an ink supply path communicating with the pressure chamber and filling the pressure chamber with ink. An ink jet manufactured by adhesively bonding a flow channel plate having a flow channel portion formed of the same, and an actuator in contact with the pressure chamber to pressurize ink in the pressure chamber and discharge ink droplets from the nozzles A recording head, wherein an ejector including at least the flow path portion and the actuator constitutes an ejector group arranged in a matrix, and a dummy hole is provided in the flow path plate on the outer periphery of the ejector group. It is characterized by having.
[0019]
In the ink jet recording head according to claim 1, since a dummy hole that does not contribute to the ejection of ink droplets is provided in the flow path plate on the outer periphery of the ejector group, the ejector flow path portion and the outer edge portion of the outer edge portion of the ejector group are provided. The other parts of the flow path have substantially the same area of the adhesive margin around the area where the adhesive is applied, and the same amount of the adhesive comes out to the flow path when the actuator is bonded.
[0020]
Further, in processing, particularly in etching, the outermost holes of the holes arranged in a matrix, that is, the dummy holes, become large, but they do not become large because the flow path portion of the ejector at the outer edge is not the outermost hole.
[0021]
Accordingly, the shape of the flow path portion of each ejector is substantially equal, and the ejection characteristics of each ejector of the ejector group arranged in a matrix are made uniform.
[0022]
In addition, the ejectors at the outer edge of the ejector group and the ejectors other than the outer edge have substantially the same supporting area around each ejector.
[0023]
Therefore, the support rigidity of each ejector is also substantially equal, and the ejection characteristics of each ejector of the ejector group arranged in a matrix are made uniform.
[0024]
According to a second aspect of the invention, in the ink jet recording head according to the first aspect, the flow path plate is formed by laminating a plurality of plates and bonding them together.
[0025]
In the ink jet recording head according to claim 2, since the dummy holes are provided on the outer periphery of the ejector group, when a plurality of plates are stacked and bonded together, the flow path portion and the outer edge of the ejector group at the outer edge of the ejector group. With respect to the flow path portion of the ejector other than the portion, the amount of adhesive around the adhesive is substantially the same area, and the amount of the adhesive flowing into the flow channel portion is the same.
[0026]
Further, in the processing for forming the flow path portion in the plurality of plates (particularly, etching), the flow path portion of the ejector at the outer edge portion is not the outermost hole, and thus does not become large.
[0027]
Accordingly, the shape of the flow path portion of each ejector is substantially equal, and the ejection characteristics of each ejector of the ejector group arranged in a matrix are made uniform.
[0028]
According to a third aspect of the present invention, in the inkjet recording head according to the first or second aspect, an ejector including at least the pressure chamber, the nozzle, the ink supply path, and the actuator is formed in a matrix. , A dummy hole is provided on the outer periphery of the ejector group disposed in the pressure chamber, and the dummy hole has substantially the same shape as the pressure chamber and is disposed at substantially the same pitch.
[0029]
According to the inkjet recording head of the third aspect, the same operation as the first or second aspect is achieved, but the dummy holes have substantially the same shape as the pressure chamber and are arranged at substantially the same pitch. Therefore, the shapes of the pressure chambers that greatly affect the ink ejection characteristics are equal.
[0030]
Further, if a large dummy hole is formed in the outer periphery of the ejector group, the rigidity of the entire ink jet recording head decreases. For this reason, the vicinity of the center of the ejector group is bent, and the ejection characteristics of the ejectors arranged near the center become unstable.
[0031]
However, as described above, since the dummy holes have substantially the same shape as the pressure chambers and are arranged at substantially the same pitch, the rigidity of the entire ink jet recording head does not decrease.
[0032]
Accordingly, the ejection characteristics of the ejectors of the ejector group in which the ejectors are arranged in a matrix are more uniform while maintaining the rigidity of the entire inkjet recording head.
[0033]
5. The ink jet recording head according to claim 4, wherein the ink jet recording head is formed with a pressure chamber plate in which holes serving as pressure chambers are formed, and a plurality of nozzles that communicate with the pressure chambers and eject ink droplets. A nozzle plate communicating with the pressure chamber, an ink supply path plate having a hole serving as an ink supply path for filling the pressure chamber with ink, and pressurizing the ink in the pressure chamber in contact with the pressure chamber. An ink jet recording head manufactured by adhesively bonding an actuator for ejecting ink droplets from the nozzle, wherein the dummy hole is formed at least in the pressure chamber plate, and the dummy hole formed in the pressure chamber plate is formed. 5. The ink cartridge according to claim 4, wherein the holes have substantially the same shape as the pressure chamber and are arranged at substantially the same pitch. According to Tsu preparative recording head, Sosu operations and effects similar to those of claim 1 to claim 3.
[0034]
According to a fifth aspect of the present invention, in the ink jet recording head according to the first to fourth aspects, the dummy hole surrounds a single or double outer periphery of the ejector group.
[0035]
According to the inkjet recording head of the fifth aspect, the same operation as the first to fourth aspects is achieved, but since the dummy hole surrounds the outer periphery of the ejector group in a single or double manner, the inkjet recording head of the inkjet recording head has The rigidity of the entire inkjet recording head is maintained while the shape of each ejector is made uniform without lowering the rigidity. Therefore, the vicinity of the center of the ejector group does not bend, and the ejection characteristics of the ejectors arranged near the center do not become unstable.
[0036]
According to a sixth aspect of the present invention, in the ink jet recording head according to the first to fifth aspects, the actuator is configured to convert the electric energy provided corresponding to the pressure chamber into mechanical energy. It is characterized by comprising an element and a vibrating plate which forms at least a part of a wall surface of the pressure chamber and vibrates by deformation of the piezoelectric element to expand or compress the pressure chamber.
[0037]
According to a seventh aspect of the present invention, in the ink jet recording head according to the first to fifth aspects, the actuator heats ink in the pressure chamber provided corresponding to the pressure chamber to generate bubbles. It is characterized in that it is a heat generating resistor that is pressurized by being pressed.
[0038]
The ink jet recording apparatus according to the present invention has one or more ejector groups in which the ejectors are arranged in a matrix, and the ejection characteristics of each ejector are made uniform. Since the ink jet recording head described in (1) is used, an image with excellent print quality can be formed at high speed.
[0039]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of an ink jet recording head according to the present invention will be described with reference to FIGS.
[0040]
As shown in FIGS. 1 to 4, the ink jet recording head 112 includes a nozzle 10 for discharging ink droplets, a pressure chamber 12 for discharging ink droplets from a nozzle 10 that presses and communicates with ink, a nozzle 10 and a pressure chamber 12. And an ink supply passage 18 that communicates with the pressure chamber 12.
[0041]
As shown in FIG. 1, the ejectors 50 constitute an ejector group 52 arranged in a matrix, and the inkjet recording head 112 includes three ejector groups 52.
[0042]
As shown in FIGS. 2 to 4, dummy holes 60 are arranged on the outer periphery of each ejector group 52. The dummy holes 60 have the same shape as the pressure chambers 12 of the pressure chamber plate 32 described later, and are formed at the same pitch.
[0043]
As shown in FIGS. 3 and 4, a vibration plate 34 is bonded to the upper surface of the pressure chamber 12 of the ejector 50, a piezoelectric element 36 is bonded to the upper surface of the vibration plate 34, and a ball solder is mounted to the upper surface of the piezoelectric element 36. The wiring board 38 is joined via the connection 40.
[0044]
The common ink flow path 14 and the ink supply path 18 of the ejector 50 communicate with each other through the opening 20. The common ink flow path 14 is connected to an ink supply port (not shown).
[0045]
Next, an outline of a method of manufacturing the ink jet recording head 112 will be described below.
[0046]
A nozzle plate 22 in which the nozzles 10 are formed; ink pool plates 24 and 26 in which holes for forming the nozzle communication chamber 16 and the common ink channel 14 are formed; an opening 20 of the nozzle communication chamber 16 and the common ink channel 14 A through plate 28 having holes formed therein, an ink supply path plate 30 formed with holes serving as the ink supply paths 18, and a pressure chamber plate 32 formed with holes serving as the pressure chambers 12 and the dummy holes 50 are formed. Laminate and join in order.
[0047]
The material of the nozzle plate 22 is polyimide, and the material of the nozzle plate 22, the ink pool plates 24 and 26, the through plate 28, and the pressure chamber plate 32 is SUS. The holes that become the pressure chambers 12 and the dummy holes 60 are formed by etching.
[0048]
Next, the surface of the nozzle plate 22 is coated with a water-repellent coat film (not shown), and the nozzle 10 is opened with an excimer laser.
[0049]
After the nozzle 10 is formed, the vibration plate 34 is bonded to the pressure chamber plate 32, and the piezoelectric elements 36 corresponding to the respective pressure chambers 12 are bonded to the upper surface of the vibration plate 34. Finally, the ball solder 40 is formed for each piezoelectric element 36. The wiring substrate 38 thus formed is joined to the piezoelectric element 36.
[0050]
Since the electrode layers are formed on both surfaces of the piezoelectric element 36, the electrode layers, that is, the piezoelectric element 36 and the wiring board 38 are electrically connected. The wiring board 38 and the diaphragm 34 are connected by a conductive material.
[0051]
With such a configuration, when the driving voltage waveform is applied to the piezoelectric element 36, the vibration plate 34 flexes and deforms together with the piezoelectric element 36 to pressurize the ink in the pressure chamber 12, and the ink droplets are ejected from the nozzle 10.
[0052]
Now, in this embodiment, the dummy holes 60 are formed on the outer periphery of the ejector group 52, and this operation will be described below in (1) to (3).
[0053]
(1) As shown in FIG. 5, when the pressure chamber plate 32 is bonded and bonded, the adhesive 70 comes out of the pressure chamber 12. In order to make it easy to understand, only the exfoliation of the adhesive 70 at the time of adhesive bonding between the pressure chamber plate 32 and the vibration plate 34 is shown, and the thickness of the adhesive 70 and the exfoliation B1 of the adhesive described later are shown. , B2 are shown larger than they actually are.
[0054]
Since the pressure chambers 12 of the ejectors 50 other than the outer edge of the ejector group 52 have the pressure chambers 12 of the eight adjacent ejectors 50 all around, the bonding margin 72 around which the adhesive 70 is applied is equal to the adjacent ejector 50. Of the pressure chamber 12.
[0055]
On the other hand, the pressure chamber 12 of the ejector 50 at the outer edge portion does not have the ejector 50 all around, but the dummy holes 60 having the same shape and the same pitch as the pressure chamber 12 are arranged on the outer periphery. For this reason, the adhesive margin 72 around which the adhesive 70 is applied is the same as the pressure chamber 12 of the ejector 50 other than the outer edge. Therefore, the amount of the adhesive 70 that sticks out to the pressure chamber 12 at the time of bonding is also equal (see B1 in FIG. 5A).
[0056]
Since the dummy holes 60 do not discharge ink, there is no problem even if the adhesive 70 comes off. (See B2 in FIG. 5A).
[0057]
(2) Generally, when holes arranged in a matrix in a plate are formed by etching, the outer holes tend to accumulate an edging liquid and become larger.
[0058]
The graph shown in FIG. 6 (A) shows the size of holes when holes of width L arranged in a matrix as shown in FIG. 6 (B) are formed by etching so that L becomes approximately 550 μm. 5 schematically shows the variation of the size. The horizontal axis of this graph represents the arrangement of the pressure chambers 12 formed in a matrix and the holes serving as the dummy holes 60 in the column direction (or row direction). That is, the center of the horizontal axis represents the size of the center hole, and both ends of the horizontal axis represent the size of the outermost hole.
[0059]
As can be seen from this graph, the larger the hole is from the center toward both ends (outside the holes formed in a matrix), the larger the outermost hole in particular.
[0060]
In the present embodiment, as shown in FIGS. 2 and 6B, a hole serving as the pressure chamber 12 of the ejector 50 arranged in a matrix on the SUS pressure chamber plate 32 and a dummy hole 60 on the outer periphery thereof are provided. Has formed.
[0061]
Therefore, among the holes formed in the pressure chamber plate 32, the hole that is the outermost hole having the largest hole is the dummy hole 60. Therefore, the hole serving as the pressure chamber 12 disposed at the outer edge of the ejector group 52 is not the outermost hole, and is not so large.
[0062]
Since the dummy holes 60 do not discharge ink droplets as described above, there is no problem even if the holes become large.
[0063]
(3) Ejector 50 other than the outer edge of ejector group 52 has pressure chambers 12 of eight adjacent ejectors all around, and ejector 50 other than the outer edge has pressure chamber 12 and dummy hole 60 arranged all around. ing. The dummy holes 60 have the same shape as the pressure chamber 12 and are arranged at the same pitch. For this reason, the support area (same as the bonding margins 72 and 74) around each ejector 50 is substantially equal.
[0064]
As described above, the pressure chamber 12 has the same amount of the adhesive that comes out (see B1 in FIG. 5A), and is not affected by the variation in the size that occurs due to the etching process. Therefore, the shape of the pressure chamber 12 which greatly affects the ejection characteristics of the ink droplets is substantially the same in each of the ejectors 50.
[0065]
Further, since the support rigidity of each ejector 50 is also substantially equal, the ejection characteristics of each ejector 50 of the ejector group 52 are made uniform.
[0066]
Note that, as shown in FIG. 7, even if the dummy holes 160 are larger than the pressure chambers 12, the shape and support rigidity of each ejector 50 are made uniform, but the rigidity of the entire inkjet recording head 113 is reduced by the large dummy holes 160.
[0067]
Alternatively, if a large number of dummy holes 60 are provided around the ejector group 52 over three rounds as shown in FIG. 8, for example, the shape and support rigidity of each ejector 50 can be made more uniform. As a result, the rigidity of the entire inkjet recording head 115 decreases.
[0068]
When the overall rigidity of the ink jet recording heads 113 and 115 decreases in this manner, as shown in FIGS. 7A and 8A, the vicinity of the center of the ejector group 52 is bent, and the ejector 50 disposed near the center is bent. Ink ejection characteristics become unstable.
[0069]
Therefore, the dummy holes 60 having the same shape and the same pitch as the pressure chambers 12 are provided over the outer circumference of the ejector group 52 over one circumference as shown in this embodiment, or are provided over two circumferences (not shown) (double surroundings). Is desirable.
[0070]
By providing the dummy holes 60 having the same shape and the same pitch as the pressure chambers 12 over one or two rounds of the ejector group 52, the shape of the pressure chambers 12 of each ejector 50 and the support rigidity of each ejector 50 are made uniform. In addition, since the rigidity of the entire inkjet recording head 112 is maintained, the vicinity of the center of the ejector group 52 is bent, and the ejection characteristics of the ejector 50 disposed near the center do not become unstable.
[0071]
Next, the operation of the inkjet recording head 112 according to the present embodiment will be described.
[0072]
As shown by an arrow F in FIG. 3B, ink introduced from an ink supply port (not shown) of the ink jet recording head 112 is filled in the common ink flow path 14, and passes through the ink supply path 18 from the common ink flow path 14. Each pressure chamber 12 is filled with ink.
[0073]
When the pressure chambers 12 are filled with ink, for example, when current is supplied from the ball solder 40 to the vibration plate 34, the piezoelectric element 36 is distorted, and the ink in the pressure chambers 12 is pressurized via the vibration plate 34, and a nozzle is formed. An ink droplet is ejected from 10.
[0074]
Since the dummy holes 60 are provided on the outer periphery of the ejector group 52 as described above, the ejection characteristics of the ink droplets of each ejector 50 are made uniform.
[0075]
Next, an inkjet recording apparatus 102 including the inkjet recording head 112 according to the first embodiment will be described with reference to FIG.
[0076]
The inkjet recording apparatus 102 includes a carriage 104 on which the inkjet recording head 112 is mounted, a main scanning mechanism 106 for scanning the carriage 104 in the main scanning direction M, and a sub-scanning mechanism for scanning the recording paper P as a recording medium in the sub-scanning direction S. The configuration includes a scanning mechanism 108, a maintenance station 110, and the like.
[0077]
The ink jet recording head 112 is mounted on the carriage 104 such that the nozzle plate 22 in which the nozzles 10 are formed faces the recording paper P, and moves on the recording paper P while being moved in the main scanning direction M by the main scanning mechanism 106. By discharging ink droplets, an image is recorded in a fixed band area BE. When one movement in the main scanning direction is completed, the recording paper P is conveyed in the sub-scanning direction S by the sub-scanning mechanism 108, and the next band area BE is recorded while the carriage 104 is moved in the main scanning direction M again. . By repeating such an operation a plurality of times, image recording can be performed over the entire surface of the recording paper P.
[0078]
The inkjet recording head 112 according to the present embodiment includes three ejector groups 52 in which the ejectors 50 are arranged in a matrix. Therefore, an image can be formed in a wide band area BE by one movement of the carriage 104 in the main scanning direction M. That is, image recording can be performed over the entire surface of the recording paper P with a small number of movements of the carriage 104.
[0079]
Further, as described above, since the ejection characteristics of each ejector 50 are uniform, good image formation with less unevenness can be performed. Therefore, the inkjet recording apparatus 102 can perform high-quality image formation at high speed. I have.
[0080]
Note that the present invention is not limited to the above embodiment.
[0081]
For example, in the above-described embodiment, the dummy holes 60 having the same shape and the same pitch as the pressure chambers 12 are formed in the pressure chamber plate 32, but the present invention is not limited to this. For example, dummy holes (for example, a dummy hole having the same shape and the same pitch as the ink supply path 18 in the ink supply plate 30) and the same shape and the same as the nozzle communication chamber 16 in the ink pool plates 24 and 26 are provided in other plates. Pitch dummy holes) may be formed.
[0082]
In the above-described embodiment, the nozzle 10, the pressure chamber 12, the ink supply path 18, and the nozzle communication chamber 16 are formed on separate plates and bonded to each other. However, the present invention is not limited to this. For example, the nozzles, pressure chambers, ink supply paths, and nozzle communication chambers may all be formed on one plate. Alternatively, only the nozzles may be formed in the nozzle plate, and the pressure chamber, the ink supply path, and the nozzle communication chamber may be formed in separate plates and bonded to the nozzle plate. Alternatively, another form may be used.
[0083]
Further, in the above embodiment, the piezoelectric element 36 pressurizes the pressure chamber 12 by the flexural vibration of one piezoelectric element 36, but is not limited thereto. For example, a form in which piezoelectric elements are stacked or a longitudinal vibration type piezoelectric element may be used. Alternatively, other types of piezoelectric elements may be used.
[0084]
In the above-described embodiment, the actuator includes the piezoelectric element 36 and the vibration plate 34, but is not limited to this. For example, a heating resistor which pressurizes the ink in the pressure chamber by heating and foaming the ink may be used, or a device using electrostatic force or magnetic force may be used. Alternatively, other types of actuators may be used.
[0085]
Further, in the above-described embodiment, recording is performed while the inkjet recording head 112 is conveyed by the carriage 104, but the invention is not limited to this. For example, an inkjet recording head having nozzles arranged over the entire recording medium may be used, the inkjet recording head may be fixed, and recording may be performed while transporting only the recording medium.
[0086]
Further, the ink jet recording in this specification is not limited to the recording of characters and images on recording paper. That is, the recording medium is not limited to paper, and the liquid to be ejected is not limited to ink. For example, ink is discharged onto a polymer film or glass to create a color filter for display, or solder in a welded state is discharged onto a substrate to form bumps for component mounting, for industrial use. The present invention can be applied to all droplet ejecting apparatuses used.
[0087]
【The invention's effect】
As described above, the ejection characteristics of the ejectors of the ejector group in which the ejectors of the inkjet recording head according to the present invention are arranged in a matrix can be made uniform.
[Brief description of the drawings]
FIG. 1 is a plan view of an inkjet recording head according to an embodiment of the present invention.
FIG. 2 is a plan view of an ejector group and a dummy hole of the inkjet recording head according to one embodiment of the present invention.
FIG. 3A is a diagram illustrating a main part of an inkjet recording head according to an embodiment of the present invention. (B) is an enlarged view of the X part of (A).
FIG. 4 is a cross-sectional view illustrating a main part of an inkjet recording head according to an embodiment of the present invention.
FIG. 5A is a cross-sectional view taken along the line AA of FIG. 5B, showing a main part of the ink jet recording head according to one embodiment of the present invention, and schematically showing the removal of adhesive. FIG. 3B is an enlarged view of FIG. 2 in which the ejectors and the dummy holes of the ejector group are viewed in plan.
FIG. 6A is a graph showing the variation in the size of holes when holes (pressure chambers and dummy holes) arranged in a matrix as shown in FIG. FIG. 3B is a plan view of holes (pressure chambers and dummy holes) arranged in a matrix.
FIG. 7A is a cross-sectional view of a main part of an ink jet recording head according to another embodiment of the present invention, and schematically shows cross-section AA of FIG. FIG. FIG. 3B is a plan view of the ejectors and the dummy holes of the ejector group.
FIG. 8A is a cross-sectional view taken along the line AA of FIG. 8B, showing a main part of an ink jet recording head according to another embodiment of the present invention, and schematically showing bleeding and bending of an adhesive; is there. FIG. 3B is a plan view of the ejectors and the dummy holes of the ejector group.
FIG. 9 is a view showing an ink jet recording apparatus using an ink jet recording head according to one embodiment of the present invention.
FIG. 10A is a cross-sectional view taken along the line AA of FIG. 10B, which shows a main part of a conventional ink jet recording head, and schematically shows the removal of adhesive. FIG. 4B is a plan view of the ejectors of the ejector group.
[Explanation of symbols]
10 Nozzle 12 Pressure chamber 22 Nozzle plate 18 Ink supply path 30 Ink supply path plate 32 Pressure chamber plate 34 Vibration plate (actuator)
36 Piezoelectric element (actuator)
Reference Signs List 50 ejector 52 ejector group 60 dummy hole 102 ink jet recording device 112 ink jet recording head

Claims (8)

A flow path formed with at least a pressure chamber, a nozzle communicating with the pressure chamber to discharge ink droplets, and an ink supply path communicating with the pressure chamber and filling the pressure chamber with ink. Part plate,
An actuator that comes into contact with the pressure chamber and pressurizes ink in the pressure chamber to eject ink droplets from the nozzle;
An ink jet recording head manufactured by adhesively bonding
An ejector group including at least the flow path portion and the actuator constitutes an ejector group arranged in a matrix, and a dummy hole is provided in the flow path plate on the outer periphery of the ejector group. Ink jet recording head. 2. The ink jet recording head according to claim 1, wherein the flow path plate is formed by laminating a plurality of plates and bonding them together. The ink jet recording head according to claim 1, wherein the dummy holes have substantially the same shape as the pressure chamber and are arranged at substantially the same pitch. The inkjet recording head,
A pressure chamber plate in which holes serving as pressure chambers are formed,
A nozzle plate communicating with the pressure chamber and having a plurality of nozzles from which ink droplets are ejected;
An ink supply path plate communicating with the pressure chamber and having an aperture serving as an ink supply path for filling the pressure chamber with ink;
An actuator that comes into contact with the pressure chamber and pressurizes ink in the pressure chamber to eject ink droplets from the nozzle;
An ink jet recording head manufactured by adhesively bonding
Dummy holes are provided on the outer periphery of an ejector group in which ejectors including at least the pressure chamber, the nozzle, the ink supply path, and the actuator are arranged in a matrix,
The dummy holes are formed at least in the pressure chamber plate, and the dummy holes formed in the pressure chamber plate have substantially the same shape as the pressure chamber, and are arranged at substantially the same pitch. Inkjet recording head. 5. The ink jet recording head according to claim 1, wherein the dummy hole surrounds an outer periphery of the ejector group in a single or double manner. The actuator is a piezoelectric element that converts electrical energy provided to the pressure chamber into mechanical energy, and constitutes at least a part of a wall surface of the pressure chamber, and expands or expands the pressure chamber by deformation of the piezoelectric element. 6. The ink jet recording head according to claim 1, comprising a diaphragm to be compressed. The said actuator is a heating resistor which pressurizes by heating and foaming the ink in the said pressure chamber provided corresponding to the said pressure chamber, The Claim 1 characterized by the above-mentioned. Inkjet recording head. An ink jet recording apparatus using the ink jet recording head according to claim 1.

Images