JP2001270103A - Ink-jet recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet recording head which can easily meet a plurality of kinds of ink while reducing a margin of an end part of the downstream side of a recording paper. SOLUTION: There are provided at least a reservoir plate 7 where a plurality of common ink chambers 6a-6f slim in a nozzle array direction are formed corresponding to the kinds of ink, and a branch channel plate 12 where a plurality of branch channels 11a-11f through which the common ink chambers and pressure chambers 20 communicate with each other are formed corresponding to nozzle openings 25. A plurality of kinds of branch channels through which different common ink chambers communicate with different pressure chambers are formed to the branch channel plate. Adjacent nozzle openings are made to communicate with different common ink chambers through the branch channels.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head mounted on an ink jet recording apparatus such as a printer or a plotter, and more particularly, to an ink jet recording head capable of discharging a plurality of types of ink.

[0002]

2. Description of the Related Art As an ink jet recording head capable of discharging a plurality of types of ink (hereinafter, simply referred to as a recording head), one nozzle row is divided into a plurality of blocks, and ink of a different color is discharged for each block. There is a type that discharges inks of different colors from adjacent nozzle openings.

[0003] As the former recording head, for example, there is one described in Japanese Patent Application Laid-Open No. 7-132619. In this recording head, one nozzle row is moved three times in the nozzle row direction.
Divided into three blocks, the first block is a yellow block from which yellow ink is ejected, the second block is a magenta block from which magenta ink is ejected, and the third block is a cyan block from which cyan ink is ejected. And

[0004] As the latter recording head, for example, there is one described in Japanese Patent Publication No. 3-64311. This recording head has two plates each having a comb-shaped common ink chamber. The two common ink chambers are overlapped in the plate stacking direction by sandwiching these plates between plates serving as partition walls. The comb teeth of one common ink chamber are located between adjacent comb teeth of one common ink chamber when viewed from the stacking direction. Then, by supplying inks of different colors to the respective common ink chambers, and communicating the tips of the comb teeth with the corresponding nozzle openings, inks of different colors are alternately provided from the nozzle openings along the nozzle arrangement direction. Discharge. In this recording head, a heating element is disposed in the ink flow path so as to face the nozzle opening. By controlling the heat generation of the heating element, bubbles are expanded and contracted. Is discharged.

[0005]

However, in the above-described recording head in which one nozzle row is divided into a plurality of blocks, there is a problem that a margin at a downstream end portion of the recording paper in the paper feeding direction becomes large. This is due to the paper holding structure and the mounting of the recording head in the recording apparatus.
That is, the recording head is attached to the recording apparatus in such a direction that the arrangement direction of the nozzle openings is on the paper feeding direction side, and the recording paper is provided on each of the upstream side and the downstream side of the recording head in the paper feeding direction. Paper holding part. For this reason, the downstream end of the recordable area on the recording paper is an area where the uppermost stream block can record in a state where the downstream paper pressing portion presses the downstream edge of the recording paper. In other words, even if an attempt is made to print in the most upstream block in an area downstream of the position, normal printing cannot be performed because the downstream edge of the recording paper will fall off the paper pressing portion. As a result, the area on the recording paper downstream of this position has a relatively large margin.

On the other hand, in the above-described recording head in which inks of different colors are ejected from adjacent nozzle openings, the margin at the downstream end portion of the recording paper can be reduced. However, in this recording head, since the common ink chambers are overlapped in the plate stacking direction, the more types of ink to be ejected, the greater the thickness in the plate stacking direction.
For this reason, the distance from the heating element to the nozzle opening becomes long, and the ejection characteristics of the ink may vary,
In some cases, ejection of ink droplets becomes difficult.

The present invention has been made in view of such circumstances, and an ink jet recording head which can easily cope with a plurality of types of inks while reducing the margin at the downstream end of the recording paper. The purpose is to provide.

[0008]

Means for Solving the Problems The present invention has been proposed to achieve the above object. According to the first aspect of the present invention, there is provided a nozzle array formed by arranging a plurality of nozzle openings in an array. In addition to the above, in an ink jet recording head, a series of ink flow paths from a common ink chamber to a nozzle opening via a pressure chamber are provided for each nozzle opening, and ink droplets are ejected from the corresponding nozzle opening by a change in ink pressure in the pressure chamber. A plurality of reservoir plates formed with a plurality of common ink chambers corresponding to the type of ink, and a plurality of branch passages communicating between the common ink chamber and the pressure chambers formed with a plurality of branch passages corresponding to the nozzle openings. A plurality of types of branch flow paths in which a common ink chamber communicating with the pressure chamber is different for each ink type. And, an ink jet recording head is characterized in that communicates with the common ink chamber corresponding to the nozzle openings by these branch channel.

Here, the "ink type" includes not only the type of color but also the type of coloring material such as dye or pigment, and the type of permeability to a recording medium such as high permeability or slow permeability. It is a concept.

According to a second aspect of the present invention, there is provided an ink jet recording head according to the first aspect, wherein the plurality of types of branch flow paths allow adjacent nozzle openings to communicate with different common ink chambers. is there.

According to a third aspect of the present invention, the plurality of types of branch flow paths are arranged such that the types of the inks are two or more, and the nozzle openings for discharging the same type of ink are arranged at a constant pitch. The inkjet recording head according to claim 1 or 2, wherein the inkjet recording head is arranged.

According to a fourth aspect of the present invention, there is provided the ink jet recording apparatus according to any one of the first to third aspects, wherein the branch passage plate is disposed between a pressure chamber and a reservoir plate. Head.

According to a fifth aspect of the present invention, an ink supply port for providing fluid resistance is provided between at least one of the pressure chamber and the branch passage and between the pressure chamber and the common ink chamber. The ink jet recording head according to any one of claims 1 to 4, characterized in that:

According to a sixth aspect of the present invention, in the ink jet type recording head according to the fifth aspect, the supply port plate having the ink supply port formed thereon is laminated on the branch channel plate. is there.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of an ink jet recording head to which the present invention is applied, as viewed from a piezoelectric vibrator side.
FIG. 2 is an exploded perspective view of the recording head, FIG. 3 is a diagram for explaining an ink flow path in the recording head, and FIG. 4 is a cross-sectional view of the recording head cut in a plate laminating direction.

The illustrated ink jet recording head 1
The recording head 1 (hereinafter, referred to as a recording head 1) includes an actuator unit 2 and a flow path unit 3, and is integrated with the actuator unit 2 and the flow path unit 3 in a state of being overlapped. The flow path unit 3 includes a nozzle row 4
Plate 5 having a plurality of common ink chambers 6
(6a to 6f), a reservoir plate 7, a supply port plate 10 having a supply-side communication port 9, and a branch channel 11
And the ink supply opening 1
3 is formed by laminating the supply port plates 14 formed therein and integrating them by bonding or the like. The actuator unit 2 is configured by laminating a pressure chamber plate 21 in which a pressure chamber 20 is formed and a diaphragm 23 on which a piezoelectric vibrator 22 is mounted, and integrating them by firing or the like. In the description of the recording head 1, for convenience,
The nozzle plate side is referred to as a front side, and the piezoelectric vibrator side is referred to as a rear side.

The nozzle plate 5 is made of, for example, a thin metal plate such as a stainless steel plate. The nozzle row 4 formed on the nozzle plate 5 is configured by arranging and opening a plurality of (for example, 48) nozzle openings 25 in a front-rear direction at a predetermined pitch corresponding to the dot formation density. I have. The nozzle plate 4 has two nozzle rows 4 arranged in the left-right direction.

The reservoir plate 7 is made of a stainless steel plate, which is the same metal as the nozzle plate 5. In the reservoir plate 7, a plurality of common ink chambers 6 that are elongated in the direction in which the nozzle rows 4 are formed and penetrate in the thickness direction of the plate are arranged in a horizontal direction orthogonal to the nozzle row forming direction. Has formed. In the present embodiment, three common ink chambers 6a to 6c are formed on one left and right side of the two nozzle rows 4 and 4, and three common ink chambers 6d to 6f are formed on the other side. That is, 1
Three common ink chambers are formed corresponding to the nozzle rows 4 of the rows. One ends of the common ink chambers 6a to 6f in the longitudinal direction are bent toward the left and right central sides. In addition, in the substantially left and right central portions of the reservoir plate 7,
A first nozzle communication port 26a that can communicate with the nozzle opening 25 is formed for each nozzle opening 25 (that is, at a nozzle pitch). The first nozzle communication port 26a is formed in a circular shape having a diameter larger than the diameter of the nozzle opening 25 and substantially the same as the width of the pressure chamber 20, and penetrated in the thickness direction of the plate.

In the following description, one nozzle row 4
, And the common ink chamber closest to the nozzle row 4 is the first common ink chamber 6.
a, the second closest common ink chamber to the second common ink chamber 6
b and the farthest common ink chamber is the third common ink chamber 6
c. Similarly, the common ink chamber corresponding to the other nozzle row 4 is the common ink chamber closest to the nozzle row 4, the fourth common ink chamber 6d, and the second common ink chamber is the fifth common ink chamber 6e. , And the farthest common ink chamber is referred to as a sixth common ink chamber 6f.

The branch passage plate 12 is also made of a thin stainless steel plate, which is a metal of the same material as the nozzle plate 5. The branch flow path 11 formed in the branch flow path plate 12 forms a part of an ink flow path, and communicates between the common ink chambers 6 a to 6 f and the pressure chamber 20. There are a plurality of types of branch flow paths 11, each of which has a pressure chamber 2
The common ink chambers 6a to 6f communicating with 0 are different. That is, the first branch flow path 1 corresponding to the first common ink chamber 6a
Fourth branch channel 11 corresponding to 1a or fourth common ink chamber 6d
d is a circular shape having substantially the same diameter as the width of the pressure chamber 20, and is constituted by a hole penetrating in the thickness direction of the plate. Second branch channel 11b corresponding to second common ink chamber 6b
And the fifth branch channel 11e corresponding to the fifth common ink chamber 6e.
Is formed by an elongated hole which is long in the left-right direction perpendicular to the nozzle row forming direction and penetrates through the thickness direction of the plate. The third branch channel 11c corresponding to the third common ink chamber 6c and the sixth branch channel 1 corresponding to the sixth common ink chamber 6f.
If is longer than the second branch flow path 11b and the fifth branch flow path 11e in the left-right direction and is formed by an elongated hole penetrating the plate in the thickness direction.

Further, the first branch flow path 11a and the second branch flow path 11a
Branch flow path 11b, third branch flow path 11c, and fourth branch flow path 11
d, the fifth branch flow path 11e and the sixth branch flow path 11f are arranged in a predetermined repetition order in the front-rear direction, which is the direction in which the nozzle row 4 is formed. For example, the first branch flow path 11a to the third branch flow path 11c are arranged in the order from the second ink introduction port 27b side to the third branch flow path 11a.
The branch flow path 11c, the second branch flow path 11b, and the first branch flow path 11a are repeatedly formed in this order, and the fourth branch flow path 11d to the sixth branch flow path 11f are the sixth branch flow path 11f, the fifth branch flow path 11f. The flow path 11e and the fourth branch flow path 11d are repeatedly formed in this order. The branch passage plate 12 also has the first nozzle communication port 2
A circular third nozzle communication port 26c having the same position and the same diameter as 6a is formed so as to penetrate in the thickness direction of the plate. The second ink inlet 27b is formed at a position corresponding to the tip of each of the common ink chambers 6a to 6f so as to penetrate the plate in the thickness direction.

The communication port plate 10 is also made of a thin stainless steel plate made of the same material as the nozzle plate 5. The communication port plate 10 has outlets of the branch flow paths 11a to 11f and common ink chambers 6a to 6f.
, The second nozzle communication port 26b having the same position and the same diameter as the first nozzle communication port 26a, and the same position and shape as the second ink introduction port 27b. The first ink introduction port 27a is formed to penetrate the plate in the thickness direction. The supply-side communication port 9 of the present embodiment is formed by a circular hole having a diameter substantially equal to the width of the pressure chamber 20.

The supply port plate 14 is a thin plate-like member made of a ceramic material such as zirconia.
At the same position as the first nozzle communication port 26a, a circular fourth nozzle communication port 26d having the same position and the same diameter as the first nozzle communication port 26a is formed for each nozzle opening 25. In addition, the ink supply port 13 penetrates in the thickness direction of the plate at a position outside the fourth nozzle communication port 26d on the left and right sides, more specifically, at a position separated to the left and right ends by the length of the pressure chamber 20. To be provided. This ink supply port 13
As shown in FIG. 4, has a substantially tapered shape whose diameter is reduced toward the back side on which the pressure chamber plates 21 are laminated, and its diameter, specifically, the diameter of the smallest part, is assembled to the recording head 1. In this state, the fluctuation of the ink pressure in the pressure chamber 20 is narrowed down to such an extent that the ink in the branch flow path 11 is not largely affected. The ink supply port 13 provides fluid resistance to the ink in the ink flow path. In addition, a third ink inlet 27c having the same position and shape as the first and second ink inlets 27a and 27b is formed in the supply port plate 14 so as to penetrate in the thickness direction of the plate.

The pressure chamber plate 21 is made of a thin plate of a ceramic member having a thickness suitable for forming the pressure chamber 20, for example, a plate-like alumina or zirconia having a thickness of about 100 micrometers. Pressure chamber 2
.. Are provided in a state penetrating in the thickness direction of the plate. The pressure chambers 20 are elongated holes elongated in the left-right direction, and are formed side by side in the front-rear direction at the same pitch as the pitch of the nozzle openings 25.

The diaphragm 23 is a thin plate of an elastic ceramic member having a thickness of about 6 micrometers, and in the present embodiment, is formed of a thin plate of alumina, zirconia, or the like. The piezoelectric vibrator 22 is provided on the rear surface of the vibrating plate 23.

The illustrated piezoelectric vibrator 22 is a vibrator in a flexural vibration mode, and includes an individual electrode 30, a piezoelectric layer 31, and a common electrode 32, as shown in FIG. A common electrode 32 is provided on the rear surface of the diaphragm 23. The piezoelectric layer 3 is stacked on the common electrode 32.
1 is provided. Further, individual electrodes 30 are formed on the rear surface of the piezoelectric layer 31 opposite to the common electrode 32 so as to correspond to the nozzle openings 25. These individual electrodes 3
The 0 and common electrodes 32 are made of a relatively soft conductive metal layer such as gold, and are electrically connected to a flexible wiring cable (not shown).

In the recording head 1 in which the respective plate members are laminated and integrated, as shown in FIGS. 3 and 4, the branch flow paths corresponding to the common ink chambers 6a to 6f via the supply side communication port 9. 11a to 11f communicate with the inlets of the pressure chambers 20 through the ink supply ports 13 and the corresponding branch flow paths 11
The outlets a to 11f communicate with each other, and the nozzle opening 25 communicates with the outlet of the pressure chamber 20 through the nozzle communication port 26. Therefore, the common ink chambers 6a to 6f are connected to the branch flow paths 11a to 1f.
A series of ink flow paths reaching the nozzle openings 25 through 1f and the pressure chambers 20 are formed for each nozzle opening 25.

Here, the branch passages 11a to 11f are formed between the pressure chamber 20 and the common ink chambers 6a to 6f such that the nozzle openings 25 adjacent in the nozzle row direction communicate with different common ink chambers 6a to 6f. There is communication between them. Therefore, a plurality of types of ink flow paths are formed for each of the common ink chambers 6a to 6f. That is, the first to third ink flow paths are formed corresponding to one nozzle row 4, and the fourth to sixth ink flow paths are formed corresponding to the other nozzle row 4. .

As shown in FIG. 4A, the first ink flow path is a series of ink flow paths extending from the first common ink chamber 6a to the nozzle opening 25 via the first branch flow path 11a and the pressure chamber 20. It is. The second ink flow path, as shown in FIG.
From the second common ink chamber 6b to the second branch channel 11b and the pressure chamber 2
This is a series of ink flow paths that reach the nozzle opening 25 through 0. The third ink flow path, as shown in FIG.
A series of ink flow paths from the common ink chamber 6c to the nozzle opening 25 via the third branch flow path 11c and the pressure chamber 20.
Similarly, the fourth ink flow path is a series of ink flow paths from the fourth common ink chamber 6d to the nozzle opening 25 via the fourth branch flow path 11d and the pressure chamber 20, and the fifth ink flow path is the fifth ink flow path. The sixth ink flow path is a series of ink flow paths from the common ink chamber 6e to the nozzle opening 25 via the fifth branch flow path 11e and the pressure chamber 20, and the sixth ink flow path is from the sixth common ink chamber 6f to the sixth branch flow path 1
This is a series of ink flow paths that reach the nozzle opening 25 via 1f and the pressure chamber 20.

The piezoelectric vibrator 22 contracts in the direction perpendicular to the electric field when charged to contract the pressure chamber 20, and expands in the direction perpendicular to the electric field when discharged to expand the pressure chamber 20. For this reason, by appropriately charging and discharging the piezoelectric vibrator 22, the ink pressure in the pressure chamber 20 can be changed, and the ink droplet can be ejected from the nozzle opening 25 using the change in the ink pressure. . In addition,
Between the pressure chamber 20 and the branch channel 11, an ink supply port 13 having a sufficiently small aperture is disposed. For this reason,
The influence of the fluctuation of the ink pressure in the pressure chamber 20 can be made less likely to be exerted on the branch flow path 11, which contributes to the stabilization of ink ejection. In addition, the width of the branch channel 11 is made equal to the width of the pressure chamber 20, and is sufficiently wider than the diameter of the ink supply port 13, so that it is difficult to obstruct the flow of ink. In other words, the flow resistance of the ink on the common ink chambers 6a to 6f side is smaller than that of the ink supply port 13. This also contributes to stabilization of ink ejection.

Then, the ink introduction ports 27 are communicated with the ink cartridges and the ink tanks.
By supplying different types of ink to the common ink chambers 6a to 6f through..., Different types of ink droplets can be ejected from the nozzle openings 25 adjacent in the nozzle row direction. For example, cyan ink is supplied to the first common ink chamber 6a, magenta ink is supplied to the second common ink chamber 6b, black ink is supplied to the third common ink chamber 6c, and yellow ink is supplied to the fourth common ink chamber 6d. When the light magenta ink is supplied to the fifth common ink chamber 6e and the light cyan ink is supplied to the sixth common ink chamber 6f, the nozzle openings 25 for discharging the same color ink are arranged at a constant pitch. Is done. That is, in one nozzle row 4, each of the nozzle openings 25 for discharging black ink, the nozzle openings 25 for discharging magenta ink, the nozzle openings 25 for discharging cyan ink, the nozzle openings 25 for discharging black ink, etc. The ink ejected for each nozzle opening 25 is determined. Similarly, in the other nozzle row 4, a nozzle opening 25 for discharging light cyan ink, a nozzle opening 25 for discharging light magenta ink, a nozzle opening 25 for discharging yellow ink,
The ink to be ejected for each nozzle opening 25 is determined, such as nozzle openings 25 for ejecting light cyan ink. Therefore, in each of the nozzle rows 4, 4, the nozzle openings 25 for discharging the same color are arranged every two nozzle openings 25.

As described above, since the ink droplets of different colors are ejected from the adjacent nozzle openings 25,
When the recording head 1 is attached to a recording apparatus, printing can be performed up to the vicinity of the downstream edge of the recording paper, and the margin in the portion can be reduced.

Further, between the nozzle plate 5 and the pressure chamber plate 21, only four plates of the reservoir plate 7, the communication port plate 10, the branch flow path plate 12, and the supply port plate 14 are required to be stacked. The distance from the outlet of the chamber 20 to the nozzle opening 25 can be made relatively short. Further, the number of plates to be stacked does not change even if the types of ink to be ejected increase, and it is possible to prevent the thickness in the plate stacking direction from increasing. This is because, when the type of ink to be ejected increases, the number of common ink chambers 6 formed in the reservoir plate 7 and the type of branch flow path 11 provided between each common ink chamber 6 and the pressure chamber 20 It is only necessary to increase the number. Therefore, one nozzle row 4
The distance from the outlet of the pressure chamber 20 to the nozzle opening 25 can be kept constant even if the type of ink ejected from the nozzle increases. Accordingly, even if three or more types of ink are used, it is possible to discharge the ink from one nozzle row 4 satisfactorily.

Incidentally, the present invention is not limited to the above-described embodiment, but can be variously modified. For example, the present invention is not limited to the configuration in which one nozzle row 4 discharges three color inks, but may be a configuration in which one nozzle row 4 discharges two color inks, or a configuration in which four or more color inks are discharged. It may be. Further, regarding the type of ink, not only the color but also the color material may be different, or the ink may have different permeability to recording paper (a type of recording medium). For example, the dye-based ink and the pigment-based ink may be ejected from one nozzle row 4, or the high-penetration ink and the slow-penetration ink may be ejected from one nozzle row.

In the above-described embodiment, the supply port plate 14 having the ink supply port 13 and the fourth nozzle communication port 26d is formed by the pressure chamber plate 21 and the branch flow path plate 12
Although the arrangement provided between the above is exemplified, the invention is not limited to this configuration. For example, the supply port plate 14 is disposed between the branch channel plate 12 and the reservoir plate 7, and the communication port plate 10 is disposed between the pressure chamber plate 21 and the branch channel plate 12, and the branch channel 11 is provided. The ink supply port 13 may be provided on the ink inlet side. In addition, communication port plate 1
A supply port plate 14 may be provided instead of 0, and the ink supply ports 13 and 13 may be provided on the ink inlet side and the ink outlet side of the branch channel 11, respectively. Further, the ink supply port 13 and the fourth nozzle communication port 26d are formed in the pressure chamber plate 21 or the branch channel plate 12 by half etching or the like.
May be integrally formed, and the pressure chamber plate 21 and the branch channel plate 12 may be directly joined. Similarly, the second nozzle communication port 26b and the supply-side communication port 9 are formed integrally with the branch channel plate 12 or the reservoir plate 7, and the branch channel plate 12 and the reservoir plate 7 are directly joined. It may be.

Further, in the above-described embodiment, the configuration in which the branch passage plates 12 are arranged and laminated between the pressure chamber plate 21 and the reservoir plate 7 is exemplified, but the present invention is not limited to this configuration. For example, the pressure chamber plate 21
The reservoir plate 7 may be arranged between the and the branch flow path plate 12 and stacked. In the configuration in which the branch passage plates 12 are arranged and stacked between the pressure chamber plate 21 and the reservoir plate 7, the branch passages 11 are arranged between the common ink chamber and the pressure chamber 20,
The distance from the common ink chamber to the pressure chamber 20 can be reduced, which contributes to the thinning of the recording head 1.

Further, the pressure generating element is not limited to the piezoelectric vibrator 22 of the flexural vibration mode illustrated, but may be a pressure chamber 2.
Any element that can cause pressure fluctuations in the ink within 0 may be used. For example, the piezoelectric vibrator 22 may be a longitudinal vibration mode, or a heating element that expands and contracts bubbles in the pressure chamber 20. Further, a magnetostrictive element can also be used.

[0038]

As described above, according to the present invention, the following effects are exhibited. That is, a reservoir plate in which a plurality of common ink chambers long in the nozzle row direction are formed corresponding to the ink type, and a branch in which a plurality of branch flow paths communicating between the common ink chamber and the pressure chamber are formed corresponding to the nozzle openings. A plurality of types of branch flow paths in which a common ink chamber communicated with the pressure chamber is formed for each ink type, and the branch flow paths correspond to nozzle openings. By communicating with the common ink chamber, by supplying different types of ink to each common ink chamber,
A corresponding type of ink droplet is ejected from each nozzle opening. Then, depending on how the branch flow path is formed, the nozzle openings for ejecting different types of ink can be arranged closer to each other, thereby making it possible to reduce the margin at the downstream end portion of the recording paper.

Further, a plurality of common ink chambers are formed on one reservoir plate, and a plurality of branch flow paths are formed on one branch flow path plate, and the common ink chamber and the pressure chamber are formed by the branch flow paths. Even if the type of ink ejected from one nozzle row increases, the number of common ink chambers formed in the reservoir plate can be increased and the shape of the branch channel can be easily changed even if the type of ink ejected from one nozzle row increases. Can be. Furthermore, since the number of plates to be stacked does not need to be increased even if the types of ink to be ejected increase, the thickness of the head does not change and the distance from the pressure chamber to the nozzle opening does not change. Therefore, it is possible to maintain good ejection characteristics even when the types of ink are increased.

In a configuration in which adjacent nozzle openings are communicated with different common ink chambers by a plurality of types of branch flow paths, adjacent nozzle openings eject different types of ink. Thereby, the margin at the downstream end portion of the recording paper can be further reduced.

In the configuration in which the branch flow path plate is disposed between the pressure chamber and the reservoir plate, the branch flow path is disposed between the common ink chamber and the pressure chamber. Can be shortened, and the recording head can be made thinner.

Further, in a configuration in which the supply port plate having the ink supply port is disposed at least between the pressure chamber and the branch flow path plate and between the branch flow path plate and the reservoir plate, The influence of the fluctuation of the ink pressure can be hardly given to the ink flow path on the upstream side of the pressure chamber, so that the ink ejection can be stabilized.

Further, in a configuration in which a supply port plate provided with an ink supply port is stacked and disposed on a branch channel plate,
The branch passage plate has a through portion of a predetermined shape to be a branch passage,
The supply port plate may be formed with a penetrating portion having a predetermined shape to be an ink supply port, so that processing is easy.
Therefore, each plate can be manufactured by a simple processing method such as a punching process, and the process can be simplified and the production efficiency can be improved. As a result, the recording head can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a perspective view of a recording head viewed from a piezoelectric vibrator side.

FIG. 2 is an exploded perspective view of a recording head.

FIG. 3 is a diagram illustrating an ink flow path in a recording head.

4A and 4B are cross-sectional views of the recording head cut in a plate laminating direction, wherein FIG. 4A is a cross-sectional view taken along a line AA in FIG. 3, FIG. FIG. 4 is a cross section taken along the line CC of FIG. 3.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet recording head 2 Actuator unit 3 Flow path unit 4 Nozzle row 5 Nozzle plate 6 Common ink chamber 7 Reservoir plate 9 Supply side communication port 10 Communication port plate 11 Branch flow path 12 Branch flow path plate 13 Ink supply port 14 Supply port Plate 20 Pressure chamber 21 Pressure chamber plate 22 Piezoelectric vibrator 23 Vibrating plate 25 Nozzle opening 26 Nozzle communication port 27 Ink inlet 30 Individual electrode 31 Piezoelectric layer 32 Common electrode

Claims (6)

[Claims] A nozzle array formed by arranging a plurality of nozzle openings in a line; a series of ink flow paths from a common ink chamber to a nozzle opening via a pressure chamber for each nozzle opening; In an ink jet recording head that ejects ink droplets from a corresponding nozzle opening according to a change in pressure, a reservoir plate in which a plurality of common ink chambers that are long in the nozzle row direction are formed in accordance with the type of ink; At least a branch flow path plate formed with a plurality of branch flow paths corresponding to the nozzle openings, wherein a plurality of common ink chambers communicating with the pressure chambers are different for each ink type. A plurality of types of branch flow paths, and the nozzle openings are communicated with the corresponding common ink chambers by these branch flow paths. Jet recording head. 2. The ink jet recording head according to claim 1, wherein adjacent nozzle openings are communicated with different common ink chambers by the plurality of types of branch flow paths. 3. The plurality of types of branch flow paths are arranged such that the types of ink are two or more, and nozzle openings for discharging the same type of ink are arranged at a constant pitch. The ink jet recording head according to claim 1. 4. The apparatus according to claim 1, wherein the branch channel plate is disposed between a pressure chamber and a reservoir plate.
An ink jet recording head according to any one of claims 1 to 3. 5. An ink supply port for providing fluid resistance is provided between at least one of the pressure chamber and the branch channel and between at least one of the pressure chamber and the common ink chamber. An ink jet recording head according to any one of claims 1 to 4. 6. The ink jet type recording head according to claim 5, wherein the supply port plate having the ink supply ports formed thereon is laminated on the branch channel plate.