JP2003089203A - Liquid drop discharge head and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem caused by limits on a common liquid chamber height resulting from irregularities of a channel pattern shape. SOLUTION: Pressure chambers 6 and an ink supply path 7 are formed by etching a silicon substrate. The channel pattern shape of a liquid inflow part to the supply path 7 is planar having all internal angles of 180 deg. or smaller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a droplet discharge head and an ink jet recording apparatus.

[0002]

2. Description of the Related Art An ink jet recording apparatus used as an image recording apparatus (image forming apparatus) such as a printer, a facsimile machine, a copying machine and a plotter, has a nozzle for ejecting ink droplets and a liquid chamber (ink flow path, which communicates with this nozzle). Discharge chamber,
It is also called a pressure chamber, a pressurized liquid chamber, a flow path, or the like. ) And a driving means (pressure generating means) for pressurizing the ink in the liquid chamber, an inkjet head as a droplet discharge head is mounted. As the droplet discharge head, for example, there are a droplet discharge head that discharges a liquid resist as droplets, a droplet discharge head that discharges a DNA sample as droplets, etc., but the following description will focus on the inkjet head.

As the ink jet head, the driving means is a piezoelectric element (Japanese Patent Publication No. 2-51734), and a method of heating the ink to generate bubbles and ejecting the ink by the pressure (Japanese Patent Publication No. 61-59911). Which uses electrostatic force as the driving means (Japanese Laid-Open Patent Publication No.
No. 50601).

In order to achieve high quality recording and high speed recording in such an ink jet head, it is important to increase the nozzle density. In order to achieve this high density, a method using a silicon substrate as a material for forming the pressure chamber is often adopted. This is because by using a silicon substrate having a (110) plane orientation, the partition between adjacent channels can be formed almost vertically by anisotropic etching.

FIG. 12 shows an example of a flow path pattern of a general flow path forming member using a silicon substrate in a conventional ink jet head. With this flow path forming member,
A plurality of pressure chambers 202 that communicate with a plurality of nozzles 201 that eject droplets, and a common liquid chamber 204 that supplies ink to each pressure chamber 202 via an ink supply path 203 are respectively formed. Ink is supplied to the ink supply port 205 from the outside.

[0006]

However, like the above-mentioned flow path forming member of the conventional ink jet head, the common liquid chamber 204 and the supply path 203 are provided on the silicon substrate.
When the pressure chamber 201 is formed in a continuous flow path pattern,
As shown by a region 206 in FIG. 12, the internal angle of the flow path pattern is always 180 ° at the connection part (the ink inflow part to the supply path 203) from the common liquid chamber 204 to each individual supply path 203.
The part that exceeds is generated.

However, it is usually K for processing a silicon substrate.
Anisotropic etching using an OH aqueous solution or the like is used. In this case, as described above, in the flow path pattern exceeding 180 °, a high-order surface is generated at the apex, and the etching stop property cannot be obtained. Therefore, starting from this point, the etching progresses to the outside of the pattern, and the pattern shape is deteriorated. Therefore, we have devised an initial mask pattern by predicting this pattern deterioration in advance.
There is a problem that the variation of the finished pattern is large and it is difficult to improve the variation.

Further, if the thickness of the silicon substrate is increased, the processing time at the time of penetration processing increases. For this reason, it is usually preferable to reduce the thickness so that cracking during handling can be avoided. However, when the common liquid chamber is formed in the silicon liquid chamber forming member, since the height of the common liquid chamber becomes the upper limit of the thickness of the silicon substrate, the fluid resistance value from the supply port to each supply path is improved. It is difficult to do so, which is an obstacle to the speedup.

Further, the upper limit of the total volume of the common liquid chamber is practically determined by the thickness of the silicon substrate, and it is difficult to obtain the volume necessary for suppressing the pressure fluctuation in the common liquid chamber. Therefore, there is a problem that compliance must be secured by another method.

The present invention has been made in view of the above problems, and provides a droplet discharge head that reduces variations in the flow path pattern shape and solves the problems caused by the limitation of the height of the common liquid chamber. With the goal.

[0011]

In order to solve the above problems, in the droplet discharge head according to the present invention, the pressure chamber and the supply passage are formed by etching a silicon substrate, and the liquid inflow portion into the supply passage is formed. The flow path pattern shape is a planar shape and all internal angles are 180 ° or less.

In the droplet discharge head according to the present invention, the pressure chamber and the supply path are formed by etching a silicon substrate, and the flow path pattern shape of the liquid inflow portion into the supply path is independent for each nozzle. The flow path patterns are not connected to the adjacent flow path patterns.

In each of the droplet discharge heads according to the present invention, it is preferable that the common liquid chamber for supplying the liquid to the supply passage is formed on a plane different from that of the supply passage.

In the droplet discharge head according to the present invention, the pressure chamber and the supply passage are formed by etching a silicon substrate, and the common liquid chamber is formed by a substrate different from the silicon substrate forming the supply passage. The substrate is laminated and bonded.

In each of the droplet discharge heads according to the present invention, it is preferable that a thin layer member is interposed between the common liquid chamber and the supply passage, and an independent opening is formed in the thin layer member. This thin layer member may be a diaphragm member forming a diaphragm forming the wall surface of the pressure chamber.

The ink jet recording apparatus according to the present invention is
An inkjet head to which the droplet discharge head according to the present invention is applied is mounted.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. An inkjet head according to an embodiment of the droplet discharge head of the present invention will be described with reference to FIG. In addition, this figure is an explanatory plan view for explaining the flow path shape of the same head.

In this ink jet head, a silicon substrate is used as the flow path substrate 1, and the pressure chamber 6 communicating with the nozzle 2 for ejecting ink droplets by etching this silicon substrate and the ink supply communicating with the pressure chamber 6 are connected. Road 7
Is formed. It should be noted that the flow path substrate 1 is formed with the pressure chamber 6 and the concave portion or the groove portion which becomes the ink supply passage 7, but in the present specification, it is simply expressed as the pressure chamber 6, the ink supply passage 7, and the like.

A common liquid chamber 8 is provided at the bottom of the ink supply passage 7.
An opening 9 is formed through which the ink flows in. The opening 9 is formed independently for each ink supply path 7.
Therefore, the flow path pattern shape of the ink inflow portion of the ink supply path 7 is, as shown in FIG. Further, the shape of the flow path pattern of the ink inflow portion to the supply path 7 is independent corresponding to each nozzle 4, and the flow path pattern of each supply path 7 is not connected to the flow path pattern of the adjacent supply path 7. Become.

The common liquid chamber 8 for supplying ink to the supply passage 7 is formed on a substrate (separate member) 2 different from the flow path substrate 1, and the substrate 2 forming the common liquid chamber 8 is formed. The flow path substrate 1 is laminated and bonded. Therefore, the common liquid chamber 8 and the supply passage 7 are formed on different planes, and the common liquid chamber 8 communicates with the supply passage 7 through the openings 9 independently formed corresponding to the nozzles 4, respectively. Ink is supplied from the outside through the ink supply port 10.

As described above, the pressure chambers 6 of the flow path substrate 1 and the flow path pattern shapes of the supply paths 7 are designed such that all interior angles are 180 ° or less, so that at all vertices of the flow path pattern, A high-order surface is not generated, and it is possible to suppress variations in pattern dimensions after etching. Further, by making the flow patterns of the individual pressure chambers 6 and the supply passages 7 independent of each other, it is not necessary to connect the common liquid chamber 8 and the individual pressure chambers 6 with the pattern on the silicon substrate. It is possible to make a layout in which an interior angle exceeding 0 ° is not formed.

By forming the supply passage 7 and the common liquid chamber 8 on different planes, the ink is supplied to the supply passage 7 independently from the direction facing the nozzles. The common liquid chamber 8 separated from 7 can be arranged without difficulty. Further, by forming the common liquid chamber 8 in a member (separate substrate) different from the flow channel substrate 1, the common liquid chamber 8 has no dimensional limitation due to the thickness of the silicon substrate that will be the flow channel substrate 1, It is possible to improve the fluid resistance value at the time of supply and to secure a volume that can obtain the required compliance.

Therefore, an ink jet head according to the first specific embodiment will be described with reference to FIGS. 2 is a cross-sectional explanatory view of the head along the longitudinal direction of the liquid chamber, and FIG. 3 is a plan explanatory view of the head. This ink jet head includes a flow channel substrate (liquid chamber substrate) 11 that is a liquid chamber forming member formed of a single crystal silicon substrate, a diaphragm member 12 bonded to the lower surface of the flow channel substrate 11, and a flow channel substrate 11. The pressure chamber 16 and the pressure chamber 16 which are flow paths (ink liquid chambers) having a nozzle plate 13 bonded to the upper surface and communicating with the nozzles 14 for ejecting ink droplets through the nozzle communication passages 15 and An ink supply path 17 that is a communication portion with the common liquid chamber 18 is formed.

The outer surface of the vibrating plate member 12 (the liquid chamber 1)
Piezoelectric elements 22 as driving means are bonded to the pressure chambers 16 (on the side opposite to 6) with an adhesive 23, and the other end of the piezoelectric elements 22 is bonded and fixed to a base substrate 24. . Further, an FPC cable 25 for giving a drive waveform is connected to the piezoelectric element 22. As the base substrate 24, a ceramic substrate such as barium titanate,
An insulating substrate such as alumina or forsterite is used.

Further, a resin frame member (common liquid chamber forming member) 26 is provided on the outer surface of the vibrating plate member 12 with the adhesive 2
3, and the common liquid chamber forming member 26 is connected to the common liquid chamber 1
8 and an ink supply port 27 for supplying ink to the common liquid chamber 18 from the outside. The diaphragm member 12 has an opening 19 corresponding to the common liquid chamber 18.

Here, the flow path substrate 11 is made of, for example, a single crystal silicon substrate having a plane orientation (110). (110)
By using the silicon substrate, the pressure chamber 16 having a wall surface perpendicular to the pitch direction of the nozzle can be formed, which is advantageous for miniaturization and narrow pitch. The nozzle communication hole 15 of the flow path substrate 1 is formed by, for example, a dry etching method, but it may be formed by a laser processing method, a sandblast method, or an electric discharge processing method. In addition, the recess serving as the pressure chamber 16 and the ink supply path 17 are provided.
The concave portion to be formed is formed by anisotropic etching using an alkaline aqueous solution.

The diaphragm member 12 forms a wall surface of the pressure chamber 16 to facilitate deformation, and a diaphragm portion 31 having a thickness of about 1 to 7 μm, and a piezoelectric element 22 formed outside the surface of the diaphragm portion 31. It has an island-shaped convex portion 32 for joining and connecting with, and a thick portion 33 corresponding to a partition wall portion between liquid chambers and the like. The diaphragm member 2 has a flat surface side bonded to the flow path substrate 1 with an adhesive. The diaphragm member 1
2 is formed of, for example, a nickel metal plate, but it may be formed of a resin member or a laminated member of a resin member and a metal member.

The piezoelectric element 22 has a thickness of 10 to 50 μm, for example.
m / layer zirconate titanate (PZT) and thickness of several μm /
The layers are alternately laminated with internal electrodes made of silver palladium (AgPd). The piezoelectric element 22 has a thickness of 10
Low voltage driving is possible by adopting a laminated type of 50 μm / layer. The electromechanical conversion element as the driving means is not limited to PZT.

Here, as described above, the piezoelectric element 22 is used.
The ink in the pressure chamber 16 is pressurized by using the displacement in the d33 direction (here, the displacement in the direction orthogonal to the stacking direction) as the piezoelectric direction, while the displacement in the d31 direction (here, as the piezoelectric direction of the piezoelectric element 22). It is also possible to adopt a configuration in which the ink in the pressure chamber 16 is pressurized by using the displacement in the direction orthogonal to the stacking direction).

A large number of nozzles 14, which are fine holes for ejecting ink droplets, are formed on the nozzle plate 13 so as to correspond to the tip portions of the pressure chambers 16, and the diameter of the nozzles 14 is 20 to 35 μm. There is. The nozzle plate 13 uses, for example, a Ni metal plate manufactured by an electroforming method, but silicon or other metal material, a laminated member of a metal material and a resin material, or the like can be used. Also,
A water-repellent surface treatment film is formed on the surface (ejection surface) of the nozzle plate 13.

In the ink jet head constructed as described above, 20 to 50 is selectively applied to the piezoelectric element 22.
By applying the driving pulse voltage of V, the piezoelectric element 22 to which the pulse voltage is applied is displaced in the stacking direction (when the d33 direction is used) to deform the diaphragm portion 31 of the diaphragm member 12 toward the nozzle 14, The ink in the pressure chamber 16 is pressurized by the volume / volume change of the pressure chamber 16,
Ink droplets are ejected (jetted) from the nozzles 14.

Then, as the ink droplets are ejected, the pressure chamber 1
The ink pressure in 6 decreases, and due to the inertia of the ink flow at this time, a slight negative pressure is generated in the pressure chamber 16. Under this state, by turning off the application of the voltage to the piezoelectric element 22, the diaphragm member 12 returns to its original position and the pressure chamber 16 returns to its original shape, so that a negative pressure is further generated. . At this time, the pressure chamber 16 passes from the ink supply port 27 through the common liquid chamber 18, the opening 19, and the ink supply passage 17.
Ink is filled inside. Therefore, after the vibration of the ink meniscus surface of the nozzle 4 is damped and stabilized, a pulse voltage is applied to the piezoelectric element 22 to eject the ink droplet for the next ink droplet ejection.

Also in this ink jet head, as shown in FIG. 3, the flow path pattern shape of the ink inflow portion of the ink supply path 17 is a plane shape and all interior angles are 180 °.
Since it is within the range, no higher-order surface is generated at all the vertices of the flow path pattern, and it is possible to suppress variation in pattern dimensions after etching. Further, the common liquid chamber 18 for supplying ink to the ink supply passage 17 is formed by a substrate (common liquid chamber forming member 26) different from the flow path substrate 11, so that the common liquid chamber 18 and the ink supply passage 17 are separated from each other. Since the common liquid chambers 18 are formed on different planes and communicate with the ink supply passage 17 through the openings 19 formed independently corresponding to the nozzles 4, the common liquid chamber 18 depends on the thickness of the silicon substrate to be the flow passage substrate 11. Since there is no dimensional limitation, it is possible to improve the fluid resistance value at the time of supply and to secure a volume that can obtain the required compliance.

Now, a method of manufacturing the flow path substrate 11 of the ink jet head will be described with reference to FIGS. As shown in each figure (a), using a silicon substrate 51 having a (110) plane orientation doped to p-type,
A silicon nitride film 52 is formed on the entire surface by LP-CVD, the pressure chamber surface side is patterned, and an opening pattern 53 corresponding to the pressure chamber 16 is formed.

Further, an Al film 54 is formed on the nozzle surface side by a magnetron sputtering method, the Al film 54 and the silicon nitride film 52 are continuously patterned, and an opening pattern 55 corresponding to the nozzle communication passage 15 is formed. Form.

Next, as shown in FIG. 3B, after the silicon substrate 51 is etched by ICP dry etching to form the nozzle communication path 5, only the Al film 54 is selectively removed by wet etching. . Further, as shown in FIG. 7C, the silicon substrate 51 is anisotropically etched using a KOH-based wet etchant to form the ink supply path 17 and the pressure chamber 16, and then the silicon nitride film 52 is peeled off. Then, the flow path substrate 11 is obtained.

Next, the diaphragm member 12 will be described with reference to FIG. The vibrating plate member 12 is manufactured by Ni electroforming as described above. In this case, the opening 19 that connects the common liquid chamber 18 and the ink supply passage 17 corresponds to the pattern of each pressure chamber 16 individually. I am trying to do it.

That is, for example, as shown in FIG. 7, when the diaphragm member 12 is formed with continuous openings 19 ′ for all channels which connect the common liquid chamber 18 and all the ink supply paths 17, Since a large hole is opened, the handling of parts when joining the diaphragm member 12 to the flow path substrate 11 becomes complicated. Further, when the diaphragm member 12 is manufactured by Ni electroforming as in the present embodiment, if there is a non-electroformed region with such a large area, the electroformed film thickness around it increases,
The inconvenience of uneven thickness also occurs.

Therefore, as described above, the ink supply path 1
By forming the openings 19 individually corresponding to 7, it is possible to improve the handleability of parts and prevent the occurrence of uneven thickness in electroforming.

Next, an ink jet head according to a second specific embodiment will be described with reference to FIGS. 8 and 9. 8 is a cross-sectional explanatory view of the head along the longitudinal direction of the liquid chamber, and FIG. 9 is a plan explanatory view of the head. This inkjet head includes a first substrate 61 which is a flow path substrate, a second substrate 62 which is an electrode substrate provided below the first substrate 61, and a third substrate which is provided above the first substrate 61. A pressure plate 66, which is an ink flow path through which a nozzle 64 for ejecting ink droplets communicates,
An ink supply path 67 communicating with each pressure chamber 66 is formed. The nozzle plate 63 is the nozzle plate 13 of the second embodiment.
The description is omitted because it is similar to the above.

The first substrate 61 is made of a single crystal silicon substrate, and a pressure chamber 66 and a concave portion for forming a vibration plate 70 forming a bottom portion which is a wall surface of the pressure chamber 66, and an ink supply path 67.
To form a recess. In the first substrate 61, a high-concentration boron diffusion layer 61a is formed by doping a silicon substrate with high-concentration boron, and anisotropic etching is performed using a KOH-based wet etchant to stop the high-concentration boron diffusion layer 61a. By forming the layer, the pressure chamber 66 and the ink supply path 67 are formed, and the thin layer vibration plate 70 including the high-concentration boron diffusion layer 61a is formed.
Is formed. The thickness of the first substrate 61 is 100 to
The thickness of the diaphragm 70 is 200 μm, and the thickness of the diaphragm 70 is 2 μm to 3 μm.

On the second substrate 62, an oxide film layer 72 is formed on a single crystal silicon substrate by a thermal oxidation method or the like, and the oxide film layer 7 is formed.
2 is provided with a concave portion 74, and an individual refractory metal such as titanium nitride, which is opposed to the diaphragm 70 at a predetermined gap (eg, about 0.1 to 0.3 μm), is formed on the bottom surface of the concave portion 74. The electrode 75 is formed, and the diaphragm 70 and the electrode 75 form an electrostatic actuator section. The electrode 75 is extended to the outside so that the electrode terminal portion 75
a is integrally formed.

On the surface of the electrode 75, in order to improve the durability of the electrode 75, a dielectric insulating layer (oxide film type insulating film) such as SiO ₂ film or a nitride film type insulating film such as Si ₃ N ₄ film is formed. The electrode protective film 77 is formed, but the electrode protective film 77 is not formed on the surface of the electrode 77, or the electrode protective film 77 is formed on the surface of the electrode 75 and the insulating film is formed on the diaphragm 70 side. You can also

Further, a base substrate 80, which is a separate member, is bonded to the lower surface of the second substrate 61. This base substrate 8
At 0, a recess serving as a common liquid chamber 68 to which ink is supplied from an external ink supply port 81 is formed. Further, since the common liquid chamber 68 and the individual ink supply path 67 are communicated with each other, the openings 69 are formed in the high-concentration boron diffusion layer 61b which is a vibration plate member forming the second substrate 62 and the vibration plate 70. Through holes 82 and 83 are formed.

In this ink jet head 1,
With the diaphragm 70 as the ground, the diaphragm 70 and the electrode 75
By applying a pulse voltage of, for example, about 10 to 50 V between the electrodes, a negative charge is induced on the surface of the diaphragm 70, and the electrostatic attraction force between the diaphragm 70 and the electrode 75 causes the diaphragm 70 to become an electrode. Since the pressure chamber 66 is deformed to the 75 side and the internal volume of the pressure chamber 66 increases, the pressure chamber 66 is replenished and filled from the ink supply port 81 through the common liquid chamber 68 and the opening 69, and further through the ink supply path 67.

Subsequently, when the voltage application to the electrodes 75 is turned off, the vibration plate 70 is released along with the discharge of the charges accumulated between the electrodes.
Is restored to the pressure chamber 66 side. At that time, a rapid volume change / pressure change occurs in the pressure chamber 66, and the filled ink is ejected from the nozzle 64 as an ink droplet.

Also in this ink jet head, since the flow path pattern shape of the ink inflow portion of the ink supply path 67 is a flat shape and all interior angles are within 180 °, the high-order surface is formed at every vertex of the flow path pattern. It is possible to suppress the variation in the pattern dimension after etching without generating. Further, the common liquid chamber 68 for supplying ink to the ink supply passage 67 is formed as a separate member from the flow path substrate 61, so that the common liquid chamber 68 and the ink supply passage 67 are formed on different planes, and the common liquid chamber 68 is formed. Since the chamber 68 communicates with the ink supply path 67 through the openings 69 formed independently corresponding to the nozzles, there is no dimensional limitation due to the thickness of the silicon substrate serving as the flow path substrate 61.

Next, an example of an ink jet recording apparatus equipped with an ink jet head which is a liquid droplet ejection head according to the present invention will be described with reference to FIGS. 10 and 11. 10 is a perspective explanatory view of the recording apparatus, and FIG. 11 is a side view of a mechanical portion of the recording apparatus.

In this ink jet recording apparatus, a carriage movable in the main scanning direction inside the recording apparatus main body 111, a recording head including the ink jet head according to the present invention mounted on the carriage, an ink cartridge for supplying ink to the recording head, and the like. Printing mechanism section 11 composed of
A sheet feeding cassette (or a sheet feeding tray) 114 capable of accommodating a large number of sheets 113 from the front side can be detachably attached to the lower portion of the apparatus main body 111 for accommodating 2 or the like. The manual feed tray 115 for manually feeding the paper 113 can be opened and closed, the paper 113 fed from the paper feed cassette 114 or the manual feed tray 115 is taken in, and a desired image is recorded by the printing mechanism unit 112. After that, the output tray 1 mounted on the rear side
The paper is discharged to 16.

The printing mechanism 112 slides the carriage 123 in the main scanning direction (the direction perpendicular to the paper surface in FIG. 11) by the main guide rod 121 and the sub guide rod 122, which are guide members that are laterally mounted on the left and right side plates (not shown). The carriage 123 is freely held, and yellow (Y), cyan (C),
A head 124, which is an ink jet head that is a droplet ejection head according to the present invention that ejects ink droplets of each color of magenta (M) and black (Bk), is arranged in a direction in which a plurality of ink ejection ports intersects the main scanning direction. , The ink droplet ejection direction is downward. Also, the carriage 123
Each ink cartridge 125 for supplying each color ink to the head 124 is replaceably mounted.

The ink cartridge 125 has an air port communicating with the atmosphere above, a supply port for supplying ink to the ink jet head below, and a porous body filled with ink inside. The ink supplied to the inkjet head is maintained at a slight negative pressure by the capillary force of.

Although the heads 124 for the respective colors are used here as the recording head, a single head having nozzles for ejecting ink droplets for the respective colors may be used.

Here, the carriage 123 is slidably fitted to the main guide rod 121 on the rear side (downstream side in the sheet transport direction) and slidably fitted to the slave guide rod 122 on the front side (upstream side in the sheet transport direction). It is placed in. Then, in order to move and scan the carriage 123 in the main scanning direction, a timing belt 130 is stretched between the drive pulley 128 and the driven pulley 129 which are rotationally driven by the main scanning motor 127, and the timing belt 130 is mounted on the carriage 123. The carriage 123 is reciprocally driven by the forward and reverse rotations of the main scanning motor 127.

On the other hand, in order to convey the paper 113 set in the paper feed cassette 114 to the lower side of the head 124, the paper feed roller 131 and the friction pad 132 for separately feeding the paper 113 from the paper feed cassette 114, and the paper 11 are provided.
Guide member 133 for guiding the sheet 3 and the fed sheet 11
A conveyance roller 134 that reverses and conveys 3 is provided, a conveyance roller 135 that is pressed against the peripheral surface of the conveyance roller 134, and a leading end roller 136 that defines the feed angle of the paper 113 from the conveyance roller 134. Conveyor roller 1
The sub-scanning motor 137 is rotationally driven through a gear train.

Then, a print receiving member 139, which is a paper guide member for guiding the paper 113 sent out from the carrying roller 134 below the recording head 124, corresponding to the movement range of the carriage 123 in the main scanning direction is provided. There is. A transport roller 141 and a spur 142 that are driven to rotate in order to send out the paper 113 in the paper discharge direction are provided on the downstream side of the print receiving member 139 in the paper transport direction, and further, the paper 113 is sent to the paper discharge tray 116. Roller 143 and spur 1
44, and guide members 145 and 146 that form the paper discharge path
And are arranged.

At the time of recording, by driving the recording head 124 in accordance with the image signal while moving the carriage 123, ink is ejected onto the stopped paper 113 to record one line, and the paper 113 is moved by a predetermined amount. After transportation, the next line is recorded. Upon receiving a recording end signal or a signal that the trailing edge of the paper 113 reaches the recording area, the recording operation is ended and the paper 113 is ejected. In this case, the head 12
In the ink jet head according to the present invention, which composes No. 4, the controllability of ink droplet ejection is improved and the characteristic variation is suppressed, so that an image with high image quality can be stably recorded.

A recovery device 147 for recovering the ejection failure of the head 124 is arranged at a position outside the recording area on the right end side of the carriage 123 in the moving direction. The recovery device 147 has a cap means, a suction means, and a cleaning means. The carriage 123 is moved to the recovery device 147 side while the printing is on standby, the head 124 is capped by the capping means, and the ejection port portion is kept wet to prevent ejection failure due to ink drying.
Also, by ejecting ink that is not related to recording during recording, etc., the ink viscosity of all ejection ports is made constant,
Maintains stable discharge performance.

When an ejection failure occurs, the ejection port of the head 124 is sealed by the capping means, and the bubbles are sucked together with the ink from the ejection port by the suction means through the tube. Is removed by the cleaning means and the ejection failure is recovered. Also,
The sucked ink is discharged to a waste ink reservoir (not shown) installed in the lower part of the main body, and absorbed and held by an ink absorber inside the waste ink reservoir.

As described above, by mounting the ink jet head, which is the droplet discharge head according to the present invention, variation in the shape of the flow path pattern is reduced and stable ink droplet discharge characteristics are obtained, so that high quality recording is performed. It is possible to obtain a recording device that can.

In the above embodiment, the present invention is applied to the side shooter type ink jet head in which the vibrating plate displacement direction and the ink droplet ejecting direction are the same, but the vibrating plate displacement direction and the ink droplet ejecting direction are orthogonal. The same can be applied to the edge shooter type inkjet head.

Further, in the above-described embodiment, the example in which the liquid droplet ejection head is applied to the ink jet head has been described. However, as the liquid droplet ejection head other than the ink jet head, for example, the liquid droplet ejection for ejecting the liquid resist as the liquid droplets. The present invention can also be applied to other droplet discharge heads such as a head and a droplet discharge head that discharges a DNA sample as droplets.

[0062]

As described above, according to the droplet discharge head of the present invention, the pressure chamber and the supply passage are formed by etching the silicon substrate, and the flow passage pattern shape of the liquid inflow portion into the supply passage is formed. Is flat and all interior angles are 180 °
Since it has the following shape, the variation in the flow path pattern shape is reduced, and the problem caused by the limitation of the common liquid chamber height is eliminated.

According to the droplet discharge head of the present invention, the pressure chamber and the supply path are formed by etching the silicon substrate, and the flow path pattern shape of the liquid inflow portion into the supply path corresponds to each nozzle. Independently, since each flow path pattern is not connected to the adjacent flow path pattern, it is necessary to have a liquid chamber configuration that reduces variations in flow path pattern shape and eliminates the problems caused by the limitation of the common liquid chamber height. You can

In each of these droplet discharge heads according to the present invention, since the common liquid chamber for supplying the liquid to the supply passage is formed on a plane different from that of the supply passage, the liquid inflow portion to the supply passage can be easily formed. The flow path pattern shape of can be a planar shape and all internal angles are 180 ° or less, or
It is possible to make the flow path pattern shape of the liquid inflow portion into the supply path independent for each nozzle so that each flow path pattern is not connected to the adjacent flow path pattern.

According to the droplet discharge head of the present invention, the pressure chamber and the supply passage are formed by etching a silicon substrate, and the common liquid chamber is formed of a substrate different from the silicon substrate forming the supply passage. Since these substrates are laminated and joined, it is possible to reduce the variation in the flow path pattern shape of the supply path and eliminate the problems caused by the limitation of the common liquid chamber height.

In each of these droplet discharge heads according to the present invention, a thin layer member is interposed between the common liquid chamber and the supply path, and an independent opening is formed in this thin layer member.
The common liquid chamber and the supply passage are communicated with each other, and the handling of the thin layer member is improved. The thin layer member is a vibrating plate member that forms a vibrating plate that forms the wall surface of the pressure chamber, so that a head using the vibrating plate can be easily configured.

The ink jet recording apparatus according to the present invention is
Since the droplet discharge head according to the present invention is mounted as an inkjet head that discharges ink droplets, high image quality recording can be performed.

[Brief description of drawings]

FIG. 1 is an explanatory plan view illustrating a flow path pattern shape of an inkjet head according to an embodiment of the present invention.

FIG. 2 is an explanatory sectional view taken along the longitudinal direction of the liquid chamber of the inkjet head according to the first embodiment of the present invention.

FIG. 3 is an explanatory plan view of the head.

FIG. 4 is an explanatory plan view illustrating a method of manufacturing the flow path substrate of the head.

FIG. 5 is a cross-sectional explanatory diagram illustrating a method of manufacturing the flow path substrate of the head.

FIG. 6 is an explanatory diagram for explaining a diaphragm of the head.

FIG. 7 is an explanatory diagram for explaining a diaphragm to be compared with the diaphragm.

FIG. 8 is an explanatory cross-sectional view taken along the liquid chamber longitudinal direction of the inkjet head according to the second embodiment of the present invention.

FIG. 9 is an explanatory plan view of the head.

FIG. 10 is a perspective explanatory view showing an example of an inkjet recording apparatus equipped with an inkjet according to the present invention.

FIG. 11 is an explanatory side view of a mechanism section of the recording apparatus.

FIG. 12 is an explanatory plan view of a conventional inkjet head.

[Explanation of Codes] 1 ... Flow path substrate, 2 ... Vibration plate member, 3 ... Nozzle plate, 4 ... Nozzle, 6 ... Pressure chamber, 7 ... Ink supply passage, 8 ... Common liquid chamber,
12 ... Piezoelectric element, 14 ... Base substrate, 19 ... Opening part.

Claims (7)

[Claims] 1. A plurality of nozzles for ejecting liquid droplets, a plurality of pressure chambers communicating with each nozzle, one or a plurality of common liquid chambers for supplying a liquid to each pressure chamber via a supply passage, respectively. In a droplet discharge head provided with a driving means for generating a pressure for pressurizing the liquid in the pressure chamber, the pressure chamber and the supply path are formed by etching a silicon substrate, and the liquid inflow portion into the supply path is formed. A droplet discharge head characterized in that the flow path pattern has a planar shape and all interior angles are 180 ° or less. 2. A plurality of nozzles for ejecting droplets, a plurality of pressure chambers communicating with each nozzle, one or a plurality of common liquid chambers for supplying a liquid to each pressure chamber via a supply passage, respectively. In a droplet discharge head provided with a driving means for generating a pressure for pressurizing the liquid in the pressure chamber, the pressure chamber and the supply path are formed by etching a silicon substrate, and the liquid inflow portion into the supply path is formed. A droplet discharge head characterized in that the flow path pattern shape is independent for each nozzle and each flow path pattern is not connected to an adjacent flow path pattern. 3. The droplet discharge head according to claim 1, wherein the common liquid chamber for supplying the liquid to the supply passage is formed on a plane different from that of the supply passage. head. 4. A plurality of nozzles for ejecting droplets, a plurality of pressure chambers communicating with each nozzle, one or a plurality of common liquid chambers for supplying a liquid to each pressure chamber via a supply passage, respectively. In a droplet discharge head provided with a driving unit for generating a pressure for pressurizing a liquid in the pressure chamber, the pressure chamber and the supply passage are formed by etching a silicon substrate, and the common liquid chamber is formed in the supply passage. A droplet discharge head, which is formed of a substrate different from a silicon substrate to be formed, and these substrates are laminated and bonded. 5. The droplet discharge head according to claim 3, wherein a thin layer member is interposed between the common liquid chamber and the supply passage, and an independent opening is formed in the thin layer member. A droplet discharge head characterized by: 6. The droplet discharge head according to claim 5, wherein the thin layer member is a diaphragm member that forms a diaphragm forming a wall surface of the pressure chamber. 7. An ink jet recording apparatus equipped with an ink jet head for ejecting ink droplets, wherein the ink jet head is the droplet ejecting head according to any one of claims 1 to 6. .