JPH07227966A - Lamination type ink jet recording head - Google Patents

Abstract

PURPOSE:To variously arrange various nozzles of high accuracy while achieving the standardization of an actuator unit. CONSTITUTION:Acutator units 30a, 30b, 30c independent at every nozzle groups are fixed to a common passage unit 60 having nozzles 3a, 3b, 3c divided into a plurality of groups formed thereto so that communication holes are aligned. Only by changing the arrangement form of the nozzles 3a, 3b, 3c corresponding to a purpose, heads of various types can be constituted using the same actuator units.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention closes an ink jet type recording head constituted by laminating plate materials for ejecting ink droplets to form dots on a recording sheet when print data is received.

[0002]

2. Description of the Related Art An on-demand type ink jet head, which ejects ink droplets from a plurality of nozzles in accordance with input information to output characters and figures, has higher print quality and noise than a wire dot type recording head. Is low and the running cost is low compared to page printers, and it is rapidly spreading.

In this ink jet type recording head,
A so-called face eject type ink jet head, in which a plurality of nozzles are punched in a plate to eject ink droplets in a direction perpendicular to the surface of the plate, has a high degree of freedom in nozzle arrangement, and has a laminated structure. It is characterized by being relatively simple.

FIG. 13 shows an example of an ink jet type recording head having such a laminated structure. A channel plate 94 for partitioning an elongated pressure generating chamber 96 arranged on a plane has a pressure on one surface thereof. It is configured so that it is sealed by a vibration plate 95 having a piezoelectric vibrator 97 arranged corresponding to the generation chamber 96, and the other surface is sealed by a limiting plate 93 having a limiting orifice 98.

The manifold plate 92, which is laminated on the surface of the limiting plate 93, has a through hole for defining a reservoir chamber 99 for supplying ink to each pressure generating chamber 96 via the limiting orifice 98. In the reservoir chamber 99, flow paths 100, 101, 102 for supplying ink from the ink tank are formed through the diaphragm 95, the channel plate 94, and the restriction plate 93.

The nozzle 103 for ejecting ink is bored in the nozzle plate 90 fixed to the side opposite to the vibrating plate 95, and the nozzle communication holes 104, 105, 106 for connecting the nozzle and each pressure generating chamber are respectively restricted plates. It is formed so as to penetrate through 93 and the manifold old plate 92.

In this laminated ink jet type recording head, typically, each pressure generating chamber is arranged in two rows facing each other at an interval of 0.04 inch to 0.06 inch, and nozzles are 0.02 inch. Are alternately connected to nozzles arranged in a row at a distance of 0.03 inch from.

In order to improve the recording quality of such an ink jet type recording head, it is important to make ejected ink droplets fine and increase the density of recorded pixels. Further, in order to increase the pixel density and secure the recording speed, it is also necessary to increase the number of nozzles that eject ink droplets. In particular, in color recording, one pixel is formed with pixels of three to four colors, so that inevitably a large number of nozzles and a complicated flow path structure up to that are required.

Particularly, in order to increase the density of pixels to be recorded and improve the recording quality, it is necessary to increase the array density of nozzles, and the flow path from the ink containing section to the individual nozzles has an extremely fine structure. Becomes This applies not only to the planar size and arrangement but also to the thickness. In order to process a through hole having a smaller plane size into a plate, it is necessary to make the thickness as thin as the hole diameter.

In order to solve such a problem, a plurality of recording heads are actually mounted by shifting the positions of the nozzles, but it is extremely necessary to maintain the relative positional accuracy between the recording heads. High assembly accuracy is required.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a new nozzle capable of forming a high density nozzle with a relatively simple positioning operation. Another object of the present invention is to provide a multi-layer ink jet recording head. Another object of the present invention is to provide a novel laminated ink jet recording head which can be manufactured at low cost by taking advantage of the characteristics of two units composed of different materials of a metal material and a ceramic material. .

[0012]

In order to solve such a problem, in the present invention, a nozzle plate having nozzles divided into a plurality of groups, a plurality of reservoir chambers belonging to the nozzles of each group, And a reservoir chamber forming substrate having a communicating hole communicating with the nozzle, and an ink supply port forming substrate fixed to the other surface of the reservoir chamber forming substrate and having a pressure generating chamber and a communicating hole with the nozzle. In the laminated flow path unit, a pressure generation chamber forming substrate forming a plurality of pressure generation chambers partitioned by the side wall,
An actuator unit including a vibrating plate fixed to one surface of the pressure generating chamber forming substrate and a piezoelectric vibrator formed on the surface of the vibrating plate corresponding to the pressure generating chamber is matched with the group. I fixed it more than once.

[0013]

[Function] A flow path unit which also serves as a substrate for fixing the actuator unit is constituted by a metal which is relatively easy to obtain accuracy by press working or the like, and an actuator unit is constituted by using ceramics which can be fixed by firing. , Make full use of the accuracy of the nozzle of the flow path unit.

[0014]

Embodiments of the present invention will be described below in detail with reference to the illustrated embodiments.

FIG. 1 shows an embodiment of a recording apparatus in which the laminated ink jet recording head of the present invention is mounted. Reference numeral 2 in the drawing denotes a printing mechanism portion by a carriage motor 81 in the main scanning direction ( The width direction of the recording medium 82, which is mounted on a carriage 80 that moves in the direction of arrow A in the figure, moves in the sub-scanning direction (direction of arrow B in the figure) by the paper feed motor 84 while being positioned by the platen 83. To move to.

As shown in FIG. 2, the printing mechanism section 2 is composed of an ink jet recording head 10, which will be described later, an ink containing section 70, and a head fixing member 20 for joining these.

The ink accommodating portion 70 accommodates the ink absorbing member 74 in a container that can be sealed by a lid 77 having an atmosphere communication port 76 formed therein, and has one end on the recording head 10.
Ink is recorded on the recording head 10 through a flow path 21 formed by an ink supply pipe 72 whose other end extends to the ink containing portion 70.
It is configured to be able to supply to. In addition, reference numeral 7 in the drawing
Reference numeral 1 indicates an O-ring for sealing, and reference numeral 75 indicates a filter provided in the ink supply tube 72.

With this structure, ink droplets are ejected while the recording head 10 is moved in the main scanning direction in response to a print signal, and ink is supplied from the ink container 70, and after printing one line, the recording medium 10 is ejected. The image is formed on the two-dimensional surface by moving in the sub-scanning direction.

When printing is not performed for a certain period of time or more, the standby position 8 where the ink suction means 85 is provided.
Move to 6. The ink suction means 85 is a cap 87.
And a cap advancing / retreating mechanism (not shown), and stands by in a state where the cap 87 is in contact with the nozzle surface of the recording head 10.

In the above embodiment, the ink container 70 is mounted on the carriage 80. However, an ink tank is arranged in a case or the like, and ink is supplied to the recording head 10 via a tube. You can also

FIGS. 3 and 4 show an embodiment of the ink jet type recording head 10 described above. The recording head 10 has a plate-shaped actuator unit 30 which is sufficient for mounting the same. It is configured to be fixed to the surface of a plate-like flow path unit 40 having an area. On one surface of the actuator unit 30, a flexible cable 2 for applying a drive signal to a piezoelectric vibrator described later is provided.
One end of 6 is connected.

FIG. 5 shows an embodiment of the actuator unit, which is an actuator unit 30.
Is the sealing substrate 31, the pressure generating chamber forming substrate 32, and the vibrating plate 3.
3 and 3 are sequentially laminated. On the surface of the vibrating plate 33, individually separated lower electrodes 35 are formed so as to correspond to the respective pressure generating chambers 5.
A layer of the piezoelectric vibrator 34 made of an electrostrictive material is formed corresponding to the surface of the piezoelectric vibrator 34, and the upper electrode 36 is formed on the surface of the piezoelectric vibrator 34 so as to sandwich the piezoelectric vibrator 34 with the lower electrode 35. The vibrator 34 is formed so as to groin.

That is, an individual drive signal for selectively driving the individual piezoelectric vibrators 34 is applied to the lower electrode 35. The upper electrode 36 that functions as a common electrode and the lower electrode 35 that is an individual electrode are connected to an external drive circuit by the connection terminal 37 formed on the vibration plate 33 and the flexible printed board (FP) 26. The pressure generating chambers 5 for generating the ink pressure necessary for ejecting ink droplets are arranged in a plane by the through holes formed in the pressure generating chamber forming substrate 32, and the pressure generating chambers adjacent to each other serve as side walls. The chamber is divided and separated.

Further, the sealing substrate 31 is hermetically bonded to the side wall to form a bottom wall of the pressure generating chamber 31 so as to seal the pressure generating chamber 5, and ink is supplied from outside the actuator unit for each pressure generating chamber. First communication hole 3 for supplying
8 and a second communication hole 39 for connecting to the nozzle 3 that ejects ink droplets are formed, and are connected to the pressure generating chambers 5 near both ends of each pressure generating chamber 5.

The channel unit 40 includes a nozzle plate 41.
And reservoir chamber forming substrate 42 and ink supply port forming substrate 43
And are sequentially laminated. A through hole that defines the reservoir chamber 6 is formed in the reservoir chamber forming substrate 42. By sealing one surface of the through hole with the nozzle plate 41 and the other surface with the ink supply port forming substrate 43, It is configured. The reservoir chamber 6 has a function as a manifold for branching the ink from the ink containing portion 74 to each pressure generating chamber 5, and the actuator from the portion that planarly overlaps each pressure generating chamber 5 when viewed from the substrate surface. It is formed over a portion that does not overlap the unit 30 in plan view.

In the reservoir chamber 6, ink is supplied from the reservoir chamber 6 to the pressure generating chambers 5 individually to the ink supply port forming substrate 43 at a portion that overlaps with the pressure generating chambers 5 in plan view. The mouth 4 is perforated, and a reservoir port 8 that guides the ink from the ink containing portion 74 to the reservoir chamber 6 is perforated in a region that does not planarly overlap with the actuator unit 30. Further, the nozzle plate 41 is provided with nozzles 3 for ejecting ink droplets corresponding to the pressure generating chambers 5. In order to connect the nozzle 3 and the corresponding pressure generating chamber 5, nozzle communication holes 44 and 45 are formed in the ink supply port forming substrate 43 and the reservoir forming substrate 42 so as to correspond to the nozzles 3.

The ink supply port 4 and the nozzle communication hole 44, which are opened on one surface of the flow path unit 40, respectively have a first communication hole 38 and a second communication hole 38 of the actuator unit 30 which correspond to each other one by one. The actuator unit 30 and the flow path unit 4 are formed at positions overlapping the holes 39.
By overlapping and joining the openings corresponding to 0, the flow paths between the units are connected.

Next, the ink flow in the head unit 10 consisting of the flow path unit 40 and the actuator unit 30 will be described with reference to FIG. 6 showing the sectional structure along the elongated pressure generating chamber. FIG. 6 shows the reservoir port 8 arranged in the same cross section as the pressure generating chamber 5 in order to simplify the description.
It is supplied to the pressure generating chamber 5 via the reservoir chamber 6, the ink supply port 4, and the communication hole 38. The ink supply port sucks the ink from the nozzle 3 by using the ink suction means 85 when the ink is filled into the channel for the first time, when bubbles are generated in the channel, or when the viscosity of the ink increases. It is forcibly discharged.

Further, at the time of printing, the ink flows from the ink containing portion into the pressure generating chamber 5 by the capillary force of the meniscus formed in the nozzle 3. The piezoelectric vibrator 34 constitutes a unimorph vibrator together with the vibration plate 33, and the piezoelectric vibrator 34 contracts in the in-plane direction when a voltage is applied to the piezoelectric vibrator 34. The vibrating plate 33 is flexibly deformed in a direction of contracting the pressure generating chamber 5 to generate pressure in the pressure generating chamber 5.
Due to this pressure, an ink flow from the pressure generation chamber 5 to the nozzle 3 through the communication passage 39 and the nozzle communication holes 44 and 45 is generated, and an ink droplet is ejected from the nozzle 3.

By the way, in this embodiment, the nozzle plate 41 has a two-layer structure of a thin portion 41a and a thick portion 41b, and only the vicinity of the communication hole 45 connected to the nozzle 3 is constituted as the thin portion 41a. Has been done. The nozzle plate 41 can secure strength such as chrome in a region other than the vicinity of the nozzle 3 after the nozzle 3 is punched in a metal plate elastically deformable by the pressure of the ink from the pressure generating chamber 5 by press working or the like. It is configured by plating to a thickness to form a thick portion 41b.

As described above, the thin portion 4 is provided only near the nozzle 3.
1a is provided, and the thin portion 41a in the vicinity of the communication hole 45 is elastically deformed under the pressure of the pressure generating chamber 5 by forming the thick portion 41b in the other region, so that the compliance required for ink droplet ejection is ensured. On the other hand, particularly in the case of forming a recording head in which a plurality of actuator units to be described later are fixed, it is possible to increase the rigidity and reduce the deflection as much as possible. Further, since the nozzle 3 is located at a position one step lower, it is possible to prevent contact with the recording paper or the like.

In this embodiment, two rows of pressure generating chambers 5 are formed so as to face one actuator unit 30, and they are displaced from each other by ½ of the pressure generating chamber arrangement interval in the arrangement direction. It is arranged. Corresponding nozzles 3 are also arranged in two rows, offset from each other by one half of the nozzle arrangement interval. Therefore, the arrangement interval of the nozzles 3 viewed from the main scanning direction A is one half of the pressure generating chamber interval, and the arrangement density of the nozzles 3 is substantially doubled.

In one actuator unit 30,
The pressure generating chambers can be arranged in one row or three rows or more, but if the two rows are arranged, the power supply lines to the piezoelectric vibrators can be arranged in the spaces on both sides of the actuator unit 30. The structure can be simplified.

In the above-described embodiment, ink is supplied to the pressure generating chambers in two rows via the common V-shaped or U-shaped reservoir chambers 6, but the pressure generating chambers in each row are provided. By connecting an independent reservoir chamber to
It is possible to eject ink droplets of different colors from each nozzle row.

Next, a specific example of the above-mentioned flow path unit 40 will be described. A nozzle plate 41 made of a stainless steel plate having a thickness of 50 μm and a thickness of 150 μm has nozzles 3 formed of tapered holes having an opening diameter of 30 to 50 μm and formed in two rows with an interval in the row of 564 μm. The reservoir forming substrate 42 is formed with a through hole for partitioning the reservoir chamber 6 by pressing a stainless steel plate having a thickness of 150 μm and a nozzle communicating hole 45.

The diameter of the nozzle communication hole 45 is preferably about 150 μm, which is the same as the thickness of the plate material. Ink supply port forming substrate 4
In No. 3, an ink supply port 4 and a nozzle communication hole 44 are punched by pressing a stainless steel plate having a size of 50 μm and a size of 150 μm. The ink supply hole 4 is set equal to or larger than the fluid impedance of the nozzle in order to prevent the ink flow generated by the pressure of the pressure generating chamber 5 from escaping to the reservoir chamber 6 side and direct it toward the nozzle 3 side. Is preferred.

In this embodiment, the ink supply port 4 is
The size is selected to be the same as that of the nozzle 3, and the shape is selected so that the cross section has a tapered portion that expands in the thickness direction. Because it has a taper, the diameter of the narrowest part can be made smaller than the plate thickness,
Further, it can be formed with high accuracy. Nozzle communication hole 44
The diameter of the nozzle communicating hole 45 of the reservoir chamber forming substrate 42 is
It is larger and smaller than the width of the pressure generating chamber 5, and is selected to be 200 to 300 μm. With this setting, the flow passage from the pressure generating chamber 5 to the nozzle 3 can be gradually narrowed, and it is possible to prevent bubbles from staying in the flow passage.

These three plates forming the flow path unit are laminated so that the through holes associated with each other communicate with each other. Although brazing, diffusion bonding, an adhesive, a die-cut adhesive sheet, or the like can be used for these plates, they are joined by an adhesive made of an epoxy resin that is not corroded by ink here. Each plate uses a stainless plate, but if it is a material that is not corroded by ink, it can be made from inorganic materials such as ceramics, glass, silicon, metal materials such as nickel, and plastic materials such as polyimide, polycarbonate, and polysulfone. Materials can be appropriately selected and combined according to the function of each plate.

As a processing method, the nozzle plate 4
1 and the ink supply port forming substrate 43 are relatively thin, the diameter of the hole formed is small, and high accuracy is required. Therefore, the plastic plate is processed by an excimer laser or is formed by nickel electroforming. May be.

In the present invention, since the flow path unit 40 also serves as the fixed substrate of the actuator unit 30, it is required to have high rigidity. Therefore, a metal material having both toughness and rigidity is preferable. In particular, since the size of the through hole formed in the reservoir chamber forming substrate 42 is larger than the through holes of the other plates, it is preferable to use a plate that is thicker than the other plates to ensure the rigidity.

Next, a specific example of the actuator unit 30 will be described. The pressure generating chamber forming substrate 32 is a fired body of zirunia having a thickness of 150 μm, and the plurality of pressure generating chambers 5 are formed in two rows with an in-row spacing of 564 μm like the nozzles 3. The width of the pressure generating chamber 5 is 350 to 45
The length is 0 μm and the length is 1 to 3 mm. These dimensions are
The optimum value is selected according to the amount of ink droplets required for dot formation, the nozzle array density, and the like.

The sealing substrate 31 is a fired body of zirunia having a thickness of 150 μm, and is bonded to one surface of the pressure generating chamber forming substrate 32 so as to seal one surface of the pressure generating chamber 5.
The diameter of each of the pair of communication holes 38 and 39 of the sealing substrate 31 is 3
00 μm is selected. The vibrating plate 33 is a sintered body of zirunia having a thickness of 10 to 20 μm and is bonded so as to seal the other surface of the pressure generating chamber 5. The lower electrode 35 is formed on the vibrating plate 33 so as to correspond to the pressure generating chamber 5, and the width thereof is 80% of the width of the pressure generating chamber 5 and 90% of the width of the pressure generating chamber 5.
The piezoelectric vibrator 34 is formed by stacking piezoelectric ceramic materials such as lead zirconate titanate having a thickness of 40 μm. Note that other ceramic materials such as alumina, aluminum nitride, and lead zirconate titanate can be used instead of zirconia.

Next, a method for manufacturing the above-mentioned actuator unit will be described. As shown in FIG. 7 (A), the diaphragm 33, the pressure generating chamber forming substrate 32 in which the through holes that divide the pressure generating chamber 5 are punched out in advance by the press, and the sealing in which the communication holes are punched out by the press in advance A green sheet, that is, a clay-like state, is pressure-bonded to the substrate, and then integrally fired at a temperature of 800 to 1000 ° C. This allows the substrates to be joined together without the need for an adhesive.

Next, as shown in FIG. 7B, the lower electrode 35
As platinum, palladium, silver-palladium, silver-platinum,
A pattern, which serves as an electrode, is formed on a portion corresponding to the pressure generating chamber 5 by printing a material containing at least one kind of platinum-palladium alloy as a main component, and the pattern is baked. After that, as shown in FIG.
4 is similarly laminated by printing and fired to complete an actuator unit. Then, finally, a common electrode made of chromium, gold, nickel, copper or the like is formed on the plurality of piezoelectric vibrators by a sputtering method.

In the actuator 30 thus constructed by integral firing, since the pressure generating chamber forming substrate 32 having a very fine structure and the thin diaphragm 33 are firmly joined by firing, the airtightness and the resistance are improved. In addition to being excellent in ink corrosiveness, the manufacturing process is only the work of stacking clay plates and applying the material that becomes the paste electrode or piezoelectric vibrator by printing technology and baking it. It can be manufactured extremely easily and with high accuracy.

The above-mentioned method of integrally forming by firing is very excellent, but as in the conventional method, a method of joining substrates made of metal or resin by adhesion, welding or fusion,
It goes without saying that the actuator unit can be formed by combining a method of processing glass or a silicon substrate by etching, a method of forming by plastic molding, a method of mounting a chip-shaped piezoelectric vibrator on a vibrating slope, and the like.

In the embodiment, the ink flow of the ink returning from the pressure generating chamber 5 to the reservoir chamber 6 is changed to the flow path unit 40.
The ink supply port 4 provided in
The first communication hole 38 formed in the actuator unit 30 may be narrowed to a size that can limit the return of ink.

FIG. 8 shows another embodiment of the actuator unit 30. The pressure generating chamber 5 is opened on one surface of the actuator unit 30 without providing the above-mentioned sealing substrate 31. The opening is sealed by the ink supply port forming substrate 43 of the flow path unit 40. According to this embodiment, the number of parts can be reduced and the cost can be suppressed.

Next, a method of forming various recording heads by using a plurality of the above-mentioned actuator units will be described with reference to FIGS. 9 and 10. In the figure, reference numeral 60 is a flow path unit, which is a nozzle group 3a including two rows of nozzles,
b, 3c, a nozzle plate 61 made of a metal plate having a size such that at least three actuator units 30a, 30b, 30c can be arranged without overlapping, a reservoir chamber forming substrate 62, and an ink supply port forming substrate 63 are laminated. It is configured.

The nozzle plate 61 has a nozzle plate 3a, 3b, 3c formed of nozzles 3 formed on a metal plate and has a thin portion for ensuring compliance near the nozzle 3 as shown in FIG. 41a is formed.

The reservoir chamber forming substrate 62 is used for the reservoir chamber 6
Through holes that define a, 6b, and 6c are formed, and one surface of the through holes is sealed by the nozzle plate 61, and the other surface is sealed by the ink supply port forming substrate 63.
6b and 6c are configured and have a function as a manifold for branching the ink from the ink containing portion 74 to each pressure generating chamber 5.

Each actuator unit 30a, 30
The reservoir chambers 6a, 6b, 6 are provided in the ink supply port forming substrate 63 in a region overlapping with the pressure generating chambers 5b, 30c in plan view.
c to each actuator unit 30a, 30b, 30
The ink supply ports 4a, 4b, 4c for supplying the ink to the pressure generating chambers 5a, 5b, 5c of c are perforated, and the areas from which the actuator units 30a, 30b, 30c do not overlap are separated from the ink containing portion 74. Reservoir ports 8a, 8b, 8c are provided for guiding the ink to the reservoir chambers 6a, 6b, 6c.

Ink supply ports 4a, 4b and 4c, which are opened on one surface of the flow path unit 60, and a nozzle communication hole 64.
a, 64b, 64c are formed at positions overlapping the first communication holes 38 and the second communication holes 39 of the actuator units 30a, 30b, 30c, which correspond to each other in a one-to-one relationship. 30a, 30b, 3
0c and the flow path unit 60 are joined by overlapping the corresponding openings, the flow paths of the three actuators 30a, 30b, and 30c can be connected to one flow path unit 60.

As described above, the flow path unit 60 has the independent reservoir chambers 6a, 6b, 6c for each actuator unit as described above.
Independent reservoir ports 8a, 8b, 8 corresponding to b, 6c
Since c is provided, different inks for each nozzle group 3a, 3b, 3c, for example, three color inks of cyan, magenta, and yellow are supplied to the same head, and ink droplets of different colors are ejected from the same flow path unit. It can be discharged.

Further, the flow path unit 60 can be formed of a metal having a relatively high rigidity, as well as being capable of forming the nozzle hole with high positional accuracy by press working which is a simple working method. . On the other hand, the actuator units 30a, 30b, 30c are made of ceramics that can be fixed by firing and have an essentially electrical insulating property, but as they become larger, warp or undulation easily occurs during firing.

Therefore, the actuator unit 30
By making a, 30b, and 30c as small as possible to increase the manufacturing yield, and by adhering them to the common channel unit 60 in which the nozzles are formed with high positional accuracy, high density can be obtained. It is possible to manufacture a large-sized recording head provided with a high-precision nozzle with a high yield. Further, since the piezoelectric vibrator 34 to which the drive signal is applied can be formed on the vibration plate 33 which is made of ceramic and essentially has electric insulation, no special insulation pretreatment for electrode formation is required. .

FIG. 11 shows an embodiment in which the actuator units 30a, 30b and 30c for each color are used to form dots corresponding to each color of cyan magenta and yellow.
The relative position between the nozzle 3 and the pressure generating chamber 5 is shown.

In this recording head, the nozzles of the respective colors are arranged at the same position in the sub-scanning direction B so that the ink image can be formed at the same position. Focusing on one color, there are two rows of pressure generating chambers arranged at a pitch P1 facing each other, and the pressure generating chambers are arranged so as to be offset from each other by a pitch P2 which is half the pitch P1 in the sub-scanning direction. Therefore, the substantial nozzle density in the sub-scanning direction is P2.

Generally, since each ink has different properties, it is difficult to obtain the best image with the same flow path configuration. However, in the ink jet type recording head of the present invention, the shape of the nozzle 3 of the flow path unit 60 and the ink. Supply ports 4a, 4b, 4c
Even if the actuator unit is configured to have the same structure, the best image can be obtained only by optimally adjusting the shape and the shape for each ink. As a result, it is only necessary to manufacture the same actuator unit, so it is possible to expect cost reductions due to mass production effects.

Further, an ink jet type recording head for ejecting ink of different ink droplet amounts from each of the nozzle groups 3a, 3b, 3c can be provided by simply changing the shape of the nozzle 3 or the shape of the ink supply port 4 of the flow path unit 60. Since it can be configured, it is possible to obtain an ink jet type recording head whose density can be changed smoothly even if the same actuator unit is used.

FIG. 12 shows an embodiment in which an ink jet type recording head having a high dot density is constructed by using a plurality of actuator units 30a, 30b, 30c. In this embodiment, one actuator unit is used. The two rows of nozzles corresponding to the actuator units 30a, 30b, 30c are arranged at a pitch of 6p, and are arranged side by side in the sub-scanning direction B with a shift of p. The corresponding two rows of pressure generating chambers are juxtaposed in the sub-scanning direction B with a pitch of 3p, so that the nozzles are arranged offset from the central axis of the pressure generating chambers.

Three actuator units 30a, 3
The nozzle rows corresponding to 0b and 30c are displaced from each other by 2p pitches in the sub-scanning direction B, and accordingly, when viewed from the main scanning direction B, the nozzles are arranged at p-pitch intervals. That is, the pressure generating chambers 5 arranged at the pitch 6p can be used to form dots at a density six times that.

As described above, in the present invention, 1
By mounting a plurality of actuator units on one common flow channel unit 60, it is possible to easily configure a recording head corresponding to various applications, only by changing the fixing position of the same actuator unit to the flow channel unit. You can

Further, since the actuator unit is dispersed and mounted in the same flow path unit 60, not only the heat of the piezoelectric vibrator can be quickly dissipated, but also the heat of the metal or the like can be passed through with relatively high accuracy. While the accuracy of the position and size of the nozzle can be defined by the flow path unit capable of forming the holes, the larger the size, the smaller the size of the activator unit, which makes firing more difficult.

[0065]

As described above, in the present invention, the nozzle plate having the nozzles divided into a plurality of groups, the plurality of reservoir chambers belonging to the nozzles of each group, and the communication hole communicating with the nozzles are provided. A reservoir is formed on the other side of the reservoir chamber forming substrate, and a pressure generating chamber is fixed to the other surface of the reservoir chamber forming substrate, and an ink supply port forming substrate having a communication hole with a nozzle is stacked. Pressure generating chamber forming substrate forming a plurality of pressure generating chambers, a vibrating plate fixed to one surface of the pressure generating chamber forming substrate, and a piezoelectric formed on the surface of the vibrating plate corresponding to the pressure generating chambers. Since a plurality of actuator units consisting of vibrators are made to match the above-mentioned groups and fixed, the actuator unit is made of metal that is relatively easy to produce by press working. Not only the flow path unit that also serves as a substrate for fixing the unit can be configured, the nozzle can be formed with high positional accuracy, but also the actuator unit made of ceramics that can be fixed by firing can be downsized and the firing yield can be improved. Can improve
Furthermore, even if the same actuator is used, it is possible to construct recording heads for various purposes by simply changing the structure of the flow path unit, which can be relatively changed in design.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a recording apparatus to which an inkjet recording head of the present invention is applied.

FIG. 2 is a sectional view showing an example of an ink jet type recording head of the present invention.

FIG. 3 is a diagram showing an ink jet recording head configured by fixing one actuator unit to a flow path unit.

FIG. 4 is a diagram showing a structure of the recording head on the side of an actuator unit.

FIG. 5 is an exploded perspective view showing the internal structure of the recording head.

FIG. 6 is a diagram showing a cross-sectional structure of the same recording head as above.

7A, 7B, and 7C are views showing a method of manufacturing an actuator unit used in the recording head of the present invention.

FIG. 8 is a diagram showing another embodiment of the recording head of the above.

FIG. 9 is an exploded perspective view showing an embodiment of the ink jet recording head of the present invention.

FIG. 10 is a diagram showing a structure of an ink jet recording head of the present invention on a side to which an actuator unit is attached.

FIG. 11 is a diagram showing another embodiment of the ink jet recording head of the present invention in the form of arrangement of pressure generating chambers and nozzles.

FIG. 12 is a diagram showing another embodiment of the ink jet recording head of the present invention in the form of arrangement of pressure generating chambers and nozzles.

FIG. 13 is a diagram showing an example of a conventional laminated ink jet recording head.

[Explanation of symbols]

 3 Nozzle 4 Ink Supply Hole 5 Pressure Generation Chamber 6 Reservoir Chamber 26 Flexible Cable 30 Actuator Unit 30a, 30b, 30c Actuator Unit 31 Sealing Substrate 32 Pressure Generation Chamber Formation Substrate 33, 53 Vibration Plate 34 Piezoelectric Vibrator 35 Lower Electrode 36 Upper Electrode 38 First Communication Hole 39 Second Communication Hole 40 Flow Channel Unit 43 Ink Supply Port Formation Substrate 60 Flow Channel Unit 61 Nozzle Plate 62 Reservoir Chamber Formation Substrate 63 Ink Supply Port Formation Substrate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Watanabe 3-3-5 Yamato, Suwa-shi, Nagano Seiko Epson Corporation (72) Minor Usui 3-3-5 Yamato, Suwa-shi, Nagano Seiko Epson Incorporated (72) Inventor Mari Sakai 3-5 Yamato, Suwa City, Nagano Seiko Epson Corporation

Claims (7)

[Claims] 1. A nozzle plate on which nozzles are divided into a plurality of groups, a plurality of reservoir chambers belonging to the nozzles of each group, and a reservoir chamber forming substrate having a communication hole communicating with the nozzles, A plurality of pressure generating chambers partitioned by side walls are provided in a flow path unit that is fixed to the other surface of the reservoir chamber forming substrate and is laminated with a pressure generating chamber and an ink supply port forming substrate having a communication hole with a nozzle. A pressure generating chamber forming substrate to be formed, a diaphragm fixed to one surface of the pressure generating chamber forming substrate, and a piezoelectric vibrator formed on the surface of the diaphragm corresponding to the pressure generating chamber. A laminated ink jet recording head in which a plurality of actuator units are aligned and fixed to the group. 2. The multi-layer ink jet recording head according to claim 1, wherein the flow path unit is made of a metal plate and fixed by an adhesive, and the actuator unit is made of ceramic and fixed by firing. 3. The ink jet recording head according to claim 1, wherein the ink supply port forming substrate is provided with through holes for supplying ink to the respective reservoir chambers from the outside. 4. The ink jet recording head according to claim 1, wherein the nozzles are displaced by a certain amount for each group. 5. The ink jet recording head according to claim 1, wherein the nozzles are divided into three groups, and inks of different colors are supplied to the reservoirs belonging to each group. 6. The laminated ink jet recording head according to claim 1, wherein a common flexible cable is connected to the plurality of actuators. 7. The laminated ink jet recording head according to claim 1, wherein the nozzle plate is formed as a thin portion in the vicinity of the nozzle.