JP2002254642A - Ink jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet head excellent in its ink drop ejection stability and reduced in wasteful consumption of ink. SOLUTION: An ink supply member 21 and a head tip 20 are bonded together to form a common liquid camber 8, while a convex part 23 making the end part wall face of the common liquid chamber 8 rounded is provided in the ink supply member 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head.

[0002]

2. Description of the Related Art As an ink jet head used in an image recording apparatus such as a printer, a facsimile, a copying apparatus, a plotter or an ink jet recording apparatus used as an image forming apparatus, a nozzle for discharging ink droplets and a pressurizing chamber ( Ink flow path, ink chamber, ejection chamber,
It is also called a pressure chamber, a pressurized liquid chamber, or the like. ), A common liquid chamber communicating with the pressurizing chamber via a fluid resistance portion, and pressure generating means for pressurizing the ink in the pressurizing chamber, for example, an electromechanical transducer such as a piezoelectric element, or an electrothermal transducer such as a heater. Alternatively, an ink droplet is ejected from a nozzle by deforming the pressure / volume in a pressurized chamber by providing a diaphragm that forms a wall surface of an ink flow path and an electrode facing the diaphragm.

[0003] For example, as an electrostatic type ink jet head, there is one described in, for example, JP-A-11-300959. As shown in FIGS. 12 and 13, the inkjet head includes a first substrate (flow path substrate) 201, a second substrate (electrode substrate) 202 joined to the lower surface of the first substrate 201, and an upper surface of the first substrate 201. The joined third substrate (lid member) 203 is laminated and joined to the first substrate via a nozzle groove 204, a pressurizing chamber 206 communicating with the nozzle groove 204, and a pressurizing chamber 206 via a fluid resistance portion 207. A common liquid chamber 208 and a vibrating plate 210 forming a bottom surface of the pressurizing chamber 206 are provided, and the vibrating plate 21 is provided on the second substrate 202.
The electrode facing 0 is arranged.

[0004]

Incidentally, in a recording head using an ink-jet head, when a cartridge is exchanged or a bubble enters the pressurizing chamber and printing failure occurs, the nozzle is sealed with a cap member. The return operation is performed by stopping and applying a negative pressure to discharge the ink of the ink cartridge from the nozzle through the pressurizing chamber.

However, in the above-mentioned conventional ink jet head, when ink is filled from an ink cartridge or the like, bubbles B stay in the common liquid chamber 208,
There is a problem that this adversely affects the ink ejection performance.

That is, when the ink is filled, the common liquid chamber 20
8, a common liquid chamber 20 is supplied from an ink supply port (not shown).
8, an ink flow 209 to each pressurizing chamber 206 is generated. In this case, the flow rate of the ink is relatively high in the center portion due to the flow of the ink to the respective pressurizing chambers 206, but the flow of the ink is low at the end sides (both ends) 210 of the common liquid chamber 208. Extremely low, stagnation occurs, and bubble B
Is not discharged and stays at the end 210 of the common liquid chamber 208.

In particular, since a pressurizing chamber, a vibration plate, a common liquid chamber, and the like are formed by anisotropic etching using a silicon substrate as the substrate 201, the cross-sectional shape of the common liquid chamber 208 is as shown in FIG. Since it has a shape (a sharp angle) and a constant cross-sectional area, the structure is easy to trap air bubbles.

In particular, if the number of nozzle openings in one row increases, the ink flow velocity at the time of ink discharge in the end area in the row direction in the common liquid chamber becomes slow. Stay at the end of the. In order to discharge the bubbles remaining at the end as described above, it is necessary to suck a large amount of ink, and there is a problem that ink is wasted.

In addition, if there is a bubble at the end of the common liquid chamber, the flow of the ink into the nearby pressurizing chamber becomes a flow path resistance. Therefore, the flow of the ink deteriorates and the necessary ink supply cannot be secured. In some cases, the ejection becomes unstable, or due to some disturbance such as vibration, the staying air bubbles move into the pressurized chamber, causing the ejection of ink droplets to fail.

[0010] When air bubbles tend to stay at both ends of the common liquid chamber due to its shape, it is considered that the nozzles at both ends are dummy nozzles not used for recording. The ink flow becomes slower toward the end of the liquid chamber, and this is an effective means when the remaining position of the bubble is specified at both ends of the common liquid chamber. However, during the suction operation, a large amount of ink is suctioned from these dummy nozzles to remove bubbles, so that wasteful consumption of ink is inevitable.

The present invention has been made in view of the above problems, and has as its object to provide an ink jet head which is excellent in ink droplet ejection stability and consumes a small amount of wasteful ink.

[0012]

In order to solve the above-mentioned problems, an ink-jet head according to the present invention comprises a substrate provided with at least a part of pressure generating means and an ink supply having an ink supply port for supplying ink. A common liquid chamber is formed by joining the members to each other, and a convex portion for rounding the end wall surface of the common liquid chamber of the substrate is provided on the joint surface side of the ink supply member. In this specification, “rounding” means
This means that the shape is such that bubbles are not easily retained, and the shape is not limited to the arc shape.

The ink jet head according to the present invention forms a common liquid chamber by joining a substrate provided with at least a part of the pressure generating means and an ink supply member having an ink supply port for supplying ink. The adhesive for joining the supply member and the substrate protrudes toward the common liquid chamber and rounds the end wall surface of the common liquid chamber of the substrate.

In the ink jet head according to the present invention, a common liquid chamber is formed by joining a substrate provided with at least a part of the pressure generating means and an ink supply member having an ink supply port for supplying ink. Of the common liquid chamber is filled with a filler to form a round shape.

In each of these ink jet heads according to the present invention, the substrate is preferably a silicon substrate. In this case, the silicon substrate may be a silicon substrate having a crystal plane orientation (100), and the cross-sectional shape of the opening forming the common liquid chamber may be narrowed in the ink supply direction. Preferably, the ink supply member is a resin member.

[0016]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an exploded perspective view of an ink jet head according to a first embodiment of the present invention, FIG. 2 is a cross-sectional explanatory view of the same head along a longitudinal direction of a diaphragm, FIG. FIG. 5 is a schematic cross-sectional view of the same head along the transverse direction of the diaphragm, and FIG. 5 is a cross-sectional view of the same head along the nozzle arrangement direction.

This ink jet head uses a flow path substrate 1 which is a first substrate using a silicon substrate such as a single crystal silicon substrate or an SOI substrate, and a silicon substrate provided below the flow path substrate 1. Electrode substrate 2 as second substrate
And a nozzle plate 3 provided on the upper side of the flow path substrate 1, a nozzle 4 for discharging a plurality of ink droplets, a pressurizing chamber 6 which is a flow path communicating with each nozzle 4, A common liquid chamber 8 and the like, which are common flow paths communicating with each other via a fluid resistance portion 7 also serving as a supply path, are formed.

A plurality of pressurizing chambers 6 with which the nozzles 4 communicate with the flow path substrate 1 and a diaphragm 10 serving as a bottom which is a wall surface of the pressurizing chamber 6 (also serves as an electrode, but if an electrode is formed separately, Good) and an opening 9 for forming the common liquid chamber 8.

In this case, for example, when a single crystal silicon substrate is used as the flow path substrate 1, boron is injected in advance to the diaphragm thickness to form a high-concentration boron layer serving as an etching stop layer. After joining, the concave portion which becomes the pressurizing chamber 6 is K
By performing anisotropic etching using an etching solution such as an OH aqueous solution, the high-concentration boron layer serves as an etching stop layer at this time, and the diaphragm 10 is formed with high precision. When an SOI substrate in which an active layer substrate is bonded to a base substrate via an oxide film is used, the diaphragm 10 is formed using the active layer substrate.

An oxide film layer 2a is formed on the electrode substrate 2 by a thermal oxidation method using a single crystal silicon substrate, and a groove (recess) 14 for forming an electrode is formed in the oxide film layer 2a. An electrode 15 facing the diaphragm 10 is provided on the bottom surface of the electrode forming groove 14, a gap 16 is formed between the diaphragm 10 and the electrode 15, and the pressurizing chamber 6 is formed by the diaphragm 10 and the electrode 15. It constitutes pressure generating means (actuator section) for generating a pressure for pressurizing the inner ink.

The electrode 15 is provided as a connecting portion (electrode take-out portion) 15a which extends to the outside and is connected to connecting means connected to an external drive circuit. On the surface of the electrode 15, an electrode protection film 17 made of an oxide-based insulating film such as a SiO ₂ film or a nitride-based insulating film such as a Si ₃ N ₄ film is formed. Note that, without forming the electrode protection film 17 on the surface of the electrode 15, or by forming the electrode protection film 17 on the surface of the electrode 15, an insulating film may be formed on the diaphragm 10 side. Further, an opening 19 for forming the common liquid chamber 8 is formed in the electrode substrate 12.

The bonding between the flow path substrate 1 and the electrode substrate 2 can be performed by an adhesive, but a more reliable physical bonding, here, the flow path substrate 1 and the electrode substrate 2
Are formed on a silicon substrate, and thus are bonded using a silicon-silicon direct bonding method. This direct bonding is performed at a high temperature of about 1000 ° C. The electrode substrate 2
Pyrex (registered trademark) glass may be formed between the substrate and the flow path substrate 1, and the film may be joined by anodic bonding via this film. Furthermore, the flow path substrate 1 and the electrode substrate 2 can be bonded by eutectic bonding in which a binder such as gold is interposed between bonding surfaces using a silicon substrate.

The electrode 15 of the electrode substrate 2 is made of A, which is generally used in a process of forming a semiconductor element.
A high-rigidity member such as l, Cr, Ni, or the like, a high-melting-point metal such as Ti, TiN, or W, or a polycrystalline silicon material whose resistance is reduced by impurities can be used. When the electrode substrate 2 is formed of a silicon wafer, it is necessary to form an insulating layer (the above-described oxide film layer 2a) between the electrode substrate 2 and the electrode 15. When an insulating material such as a glass substrate or a ceramic substrate is used for the electrode substrate 2, it is not necessary to form an insulating layer between the electrode 15 and the electrode 15.

The nozzle plate 3 is provided with a plurality of nozzles 4 and a groove for forming a fluid resistance portion 7 for communicating the common liquid chamber 8 and the pressurizing chamber 6. Here, a water-repellent film is formed on the ink ejection surface (nozzle surface side). The nozzle plate 3 includes a glass substrate, a plastic plate, a metal plate such as stainless steel, a silicon substrate, a nickel plating film formed by an electroforming (electroforming) method, a resin such as polyimide processed by excimer laser, a metal and a resin. Laminated ones and the like can be used. The nozzle plate 3 is bonded to the flow path substrate 1 with an adhesive.

Then, an ink supply member 21 is bonded to a head chip (actuator unit) 20 composed of the flow path substrate 1 and the electrode substrate 2 with an adhesive, and the head chip 20 is a substrate provided with a pressure generating means. The common liquid chamber 8 is formed with the ink supply member 21. The ink supply member 21 is formed by injection molding using a resin material.

The ink supply member 21 has an ink supply port 22 for supplying ink to the common liquid chamber 8 from an external ink tank or ink cartridge.
As shown in FIG. 5, the surface of the ink supply member 21 to be joined to the electrode substrate 2 has a substantially triangular cross section that rounds the end wall surface (the wall surface of the opening 19) of the common liquid chamber 8. Are formed. The protrusion 23 may be formed integrally with the ink supply member 21 or may be a separate member.

A joint member 25 with an ink cartridge is connected to the ink supply member 21, and a common liquid is supplied from the ink tank or the ink cartridge through the ink supply port 23 through a filter 26 which is thermally fused to the ink supply member 21. The ink is supplied to the chamber 8.

Further, an FP in which a driver IC (driving IC chip) 30 as a head driving circuit is mounted on the electrode take-out portion 15a of the head chip 20 by wire bonding.
The C cable 31 is connected via an anisotropic conductive film or the like, and the FPC cable 31 is drawn out through a hole 27 formed in the ink supply member 21.

The electrode take-out portion 15a and the nozzle plate 3 including the space between the electrode substrate 2 and the nozzle plate 3 (the entrance of the gap 16)
Is sealed airtight with a gap sealant 32 using an adhesive such as an epoxy resin to prevent the moisture from entering the gap 16 and displacing the diaphragm 10.

Further, the gap between the nozzle plate 3 on the head chip 20 and the ink supply member 21 is sealed with a gap sealing agent 33, and the ink on the surface of the nozzle plate 3 having water repellency is applied to the electrode substrate 2 or the FPC. It is prevented from going around the cable 31 or the like.

In this ink jet head, the diaphragm 10 is used as a common electrode, and the electrode 15 is used as an individual electrode.
By applying a drive voltage between the diaphragm 10 and the electrode 15, the diaphragm 10 is deformed toward the electrode 15 by an electrostatic force generated between the diaphragm 10 and the electrode 15, and from this state, the diaphragm 10 The diaphragm 10 is deformed by discharging the electric charge between the electrode 15 and the electrode 15, and the internal volume (volume) / pressure of the pressurizing chamber 6 is changed, so that the ink droplet is ejected from the nozzle 4.

That is, when a pulse voltage is applied to the electrode 15 serving as an individual electrode, a potential difference occurs between the electrode 15 and the diaphragm 10 serving as a common electrode, and an electrostatic force is generated between the individual electrode 15 and the diaphragm 10. As a result, the diaphragm 10 is displaced according to the magnitude of the applied voltage. After that, the applied pulse voltage falls, whereby the displacement of the diaphragm 10 is restored, and the restoring force increases the pressure in the pressurizing chamber 6 and the nozzle 4
Ink droplets are ejected from.

Here, the electrode substrate 2 forming the common liquid chamber 8
When the opening 19 of is formed by anisotropic etching,
An inclined surface is generated at the end of the opening 19 due to the crystal plane orientation, and the opening 19 has a sectional shape that becomes narrower in the ink supply direction. Therefore, when the end surface (joining surface) of the ink supply member 21 is joined to the back surface of the electrode substrate 2 to form the common liquid chamber 8, as shown in FIG. The air bubbles B easily stay between the supply member 21 and the end face.

Therefore, in this ink jet head, a convex portion 23 having a substantially triangular cross section for rounding a portion between the joint surface of the ink supply member 21 and both end wall surfaces of the opening 19 (both ends of the common liquid chamber 18). As shown in FIG. 6, the joining surface of the ink supply member 21 and the opening 19 are provided.
Bubbles are prevented from stagnating between both end wall surfaces. Thus, a stable ink droplet ejection operation can be performed, and wasteful consumption of ink is reduced.

Here, by forming the ink supply member 21 by injection molding using a resin material, it is possible to easily form a convex shape that rounds the end wall surface of the common liquid chamber.

Next, another embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. FIG. 2 is an explanatory cross-sectional view of the same embodiment along the nozzle arrangement direction. In this embodiment,
The common liquid chamber 8 is formed by joining the ink supply member 21 with the electrode substrate 2 of the head chip 20 which is a substrate on which the actuator section is installed, and the opening of the electrode substrate 2 forming the common liquid chamber 8 is formed. The space between the end wall surface of the portion 19 and the ink supply member 21 is filled with a filler 41 to form a round shape. As the filler 41, a sealing material such as Si rubber or the like which is cured by heating or at room temperature can be used.

As described above, the space between the joint surface of the ink supply member 21 and the wall surfaces at both ends of the opening 19 (both ends of the common liquid chamber 18) is filled with the filler 41 to form a round. Air bubbles are prevented from staying between the joint surface of the opening 21 and the end wall surfaces of the opening 19. As a result, a stable ink droplet ejection operation can be performed,
Wasted ink consumption is also reduced.

Next, still another embodiment of the present invention will be described with reference to FIG. FIG. 2 is an explanatory cross-sectional view of the same embodiment along the nozzle arrangement direction. In this embodiment, the common liquid chamber 8 is formed by joining the ink supply member 21 to the electrode substrate 2 of the head chip 20 which is a substrate on which the actuator section is installed, and the common liquid chamber 8 is formed. Between the end wall surface of the opening 19 of the electrode substrate 2 and the joining surface of the ink supply member 21,
A part of the adhesive 42 for joining the head chip 20 to the head chip 20 is protruded and rounded.

As the adhesive 42, an epoxy-based, rubber-based or the like having relatively good ink resistance can be used. The amount of protrusion of the adhesive 42 is appropriately selected in accordance with the shape of the common liquid chamber 8.
The diameter is preferably about 10 to 100 microns, which is about the same as the diameter of the stagnating bubbles.

As described above, the portion between the bonding surface of the bonding agent 42 and the portion between the bonding surface of the ink supply member 21 and both end wall surfaces of the opening 19 (both ends of the common liquid chamber 18) is formed into a round shape. This prevents bubbles from staying between the joint surface of the ink supply member 21 and the wall surfaces at both ends of the opening 19. Accordingly, a stable ink droplet ejection operation can be performed, and wasteful consumption of ink is reduced.

Next, an example of the ink jet recording apparatus according to the present invention will be described with reference to FIGS. FIG. 11 is a perspective view of the recording apparatus, and FIG. 12 is a side view of a mechanism of the recording apparatus. This inkjet recording apparatus includes a carriage movable in the main scanning direction inside a recording apparatus main body 111, a recording head including an inkjet head according to the present invention mounted on the carriage,
A printing mechanism 112 including an ink cartridge for supplying ink to the recording head, etc.
A paper feed cassette (or a paper feed tray) 11 capable of stacking a large number of papers 113 from the front side is provided at a lower portion of 1.
4 can be inserted and removed freely.
After the manual feed tray 115 for manually feeding the paper 13 can be opened, 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 112. Then, the paper is discharged to a paper discharge tray 116 mounted on the rear side.

The printing mechanism 112 slides the carriage 123 in the main scanning direction (the direction perpendicular to the plane of FIG. 15) by the main guide rod 12 and the sub guide rods 122, which are guide members that are laterally mounted on left and right side plates (not shown). The carriage 123 is provided with a plurality of heads 124 each including an inkjet head according to the present invention, which ejects ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk). The ink ejection ports are arranged in a direction crossing the main scanning direction, and are mounted with the ink droplet ejection direction facing downward. Each ink cartridge 125 for supplying each color ink to the head 124 is provided on the carriage 123.
Is exchangeably mounted.

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

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

The carriage 123 is slidably fitted on the main guide rod 112 on the rear side (downstream side in the paper transport direction), and is slidable on the front side (upstream side in the paper transport direction) on the slave guide rod 122. It is placed on. In order to move and scan the carriage 123 in the main scanning direction, a timing belt 130 is stretched between a driving pulley 128 and a driven pulley 129 which are driven to rotate by a main scanning motor 127. , And the carriage 123 is reciprocated by the forward and reverse rotation of the main scanning motor 127.

On the other hand, in order to transport the paper 113 set in the paper feed cassette 114 to the lower side of the head 124, a paper feed roller 131 and a friction pad 132 for separating and feeding the paper 113 from the paper feed cassette 114,
Guide member 133 for guiding the sheet 3 and the fed sheet 11
A transport roller 134 that reverses and transports the sheet 3, a transport roller 135 pressed against the peripheral surface of the transport roller 134, and a tip roller 136 that defines an angle at which the paper 113 is sent out from the transport roller 134 are provided. Transport roller 1
The sub-scanning motor 137 is driven to rotate via a gear train.

A print receiving member 139 is provided as a paper guide member for guiding the paper 113 sent from the transport roller 134 below the recording head 124 in accordance with the moving range of the carriage 113 in the main scanning direction. I have. On the downstream side of the printing receiving member 139 in the paper transport direction, there are provided a transport roller 141 and a spur 142 that are driven to rotate to transport the paper 113 in the paper discharge direction. Roller 143 and spur 1
44 and guide members 145, 146 forming a paper discharge path
And are arranged.

At the time of recording, the recording head 124 is driven in accordance with an image signal while moving the carriage 113, thereby discharging ink on the stopped paper 113 to record one line and recording the paper 113 by a predetermined amount. After transport, the next line is recorded. Upon receiving a recording end signal or a signal that the rear end of the sheet 113 has reached the recording area, the recording operation is terminated and the sheet 113 is discharged.

A recovery device 147 for recovering the ejection failure of the head 124 is disposed at a position outside the recording area on the right end side in the moving direction of the carriage 113. The recovery device 147 has cap means, suction means, and cleaning means. The carriage 123 is moved to the recovery device 147 side during the printing standby, the head 124 is capped by the capping means, and the ejection port is kept in a wet state, thereby preventing ejection failure due to ink drying.
Also, by ejecting ink that is not related to printing during printing or the like, the ink viscosity of all the ejection ports is kept constant,
Maintain stable discharge performance.

When a discharge failure occurs, the discharge port of the head 124 is sealed by capping means, bubbles are sucked out of the discharge port with ink by a suction means through a tube, and ink, dust, etc. adhered to the discharge port surface. 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) provided at a lower portion of the main body, and is absorbed and held by an ink absorber inside the waste ink reservoir.

In the above embodiment, the present invention is applied to the ink jet head of the side shooter type in which the diaphragm displacement direction and the ink droplet ejection direction are the same, but the diaphragm displacement direction is orthogonal to the ink droplet ejection direction. The present invention can be similarly applied to an edge shooter type ink jet head.

[0052]

As described above, according to the ink jet head of the present invention, the substrate provided with at least a part of the pressure generating means and the ink supply member are joined to form the common liquid chamber, and the ink supply is performed. Since a convex portion that rounds the end wall surface of the common liquid chamber of the substrate is provided on the bonding surface side of the member, the retention of bubbles in the common liquid chamber is reduced, and a stable ink droplet ejection operation can be performed. Waste of ink is reduced.

According to the ink jet head of the present invention, the substrate provided with at least a part of the pressure generating means is joined to the ink supply member to form a common liquid chamber, and the ink supply member is joined to the substrate. Since the agent protrudes into the common liquid chamber and the end wall surface of the common liquid chamber of the substrate is rounded, the retention of bubbles in the common liquid chamber is reduced, and a stable ink droplet ejection operation can be performed. Waste is reduced.

According to the ink jet head of the present invention, the substrate provided with at least a part of the pressure generating means and the ink supply member are joined to form a common liquid chamber, and the end wall surface of the common liquid chamber of the substrate is formed. Since the rounding is performed by filling with the filler, stagnation of bubbles in the common liquid chamber is reduced, stable ink droplet ejection operation can be performed, and wasteful consumption of ink is reduced.

In each of these ink jet heads according to the present invention, since the substrate is a silicon substrate, the shape processability of the substrate is improved. In this case, when the silicon substrate is a silicon substrate having a crystal plane orientation (100) and the cross-sectional shape of the opening forming the common liquid chamber is narrowed in the ink supply direction, the shape processability of the substrate is improved. improves. In addition, since the ink supply member is a resin member, the formation of the convex portion is facilitated.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an inkjet head according to the present invention.

FIG. 2 is an explanatory cross-sectional view of the head along a longitudinal direction of a diaphragm.

FIG. 3 is an enlarged sectional explanatory view of a main part of FIG. 2;

FIG. 4 is an explanatory cross-sectional view of the head taken along the transverse direction of the diaphragm.

FIG. 5 is an explanatory cross-sectional view of the head taken along a nozzle array direction.

FIG. 6 is an explanatory diagram for explaining the operation of the embodiment;

FIG. 7 is an explanatory diagram of a comparative example used to explain the operation of the embodiment.

FIG. 8 is a cross-sectional explanatory view along a nozzle arrangement direction of an inkjet head according to another embodiment of the present invention.

FIG. 9 is an explanatory cross-sectional view along a nozzle arrangement direction of an inkjet head according to still another embodiment of the present invention.

FIG. 10 is an explanatory perspective view illustrating a mechanism of the inkjet recording apparatus according to the invention.

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

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

FIG. 13 is an explanatory sectional view of the head.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Flow path board, 2 ... Electrode board, 3 ... Nozzle plate, 4 ... Nozzle, 6 ... Pressurizing chamber, 7 ... Fluid resistance part, 8 ... Common liquid chamber, 9 ...
Opening, 10: diaphragm, 15: electrode, 19: opening, 2
0: head chip, 21: ink supply member, 22: ink supply port, 23: convex portion, 41: filler, 42: adhesive.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seiji Hoshino 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Tomomi Kato 1-3-6 Nakamagome, Ota-ku, Tokyo Stock F-term in Ricoh Company (reference) 2C057 AF78 AG54 AG68 AP25 BA04 BA15

Claims (6)

[Claims] A pressurizing chamber communicating with a nozzle for discharging ink droplets, a common liquid chamber communicating with the pressurizing chamber via an ink supply path, and pressure generating means for pressurizing ink in the pressurizing chamber. A substrate provided with at least a part of the pressure generating means and an ink supply member having an ink supply port for supplying ink, forming the common liquid chamber, An ink jet head, wherein a convex portion for rounding an end wall surface of a common liquid chamber of the substrate is provided on a bonding surface side of the member. 2. A pressurizing chamber communicating with a nozzle for discharging ink droplets, a common liquid chamber communicating with the pressurizing chamber via an ink supply path, and pressure generating means for pressurizing ink in the pressurizing chamber. A substrate provided with at least a part of the pressure generating means and an ink supply member having an ink supply port for supplying ink, forming the common liquid chamber, An ink jet head, wherein an adhesive for joining a member and the substrate protrudes toward the common liquid chamber and rounds an end wall surface of the common liquid chamber of the substrate. A pressurizing chamber communicating with a nozzle for discharging ink droplets, a common liquid chamber communicating with the pressurizing chamber via an ink supply path, and pressure generating means for pressurizing ink in the pressurizing chamber. In the ink-jet head provided with, the substrate provided with at least a part of the pressure generating means and an ink supply member having an ink supply port for supplying ink are joined to form the common liquid chamber, An ink jet head characterized in that an end wall surface of a common liquid chamber is filled with a filler to form a round shape. 4. The ink jet head according to claim 1, wherein said substrate is a silicon substrate. 5. The ink jet head according to claim 4, wherein said silicon substrate is a silicon substrate having a crystal plane orientation of (100), and a cross-sectional shape of an opening forming said common liquid chamber narrows in an ink supply direction. An inkjet head, characterized in that: 6. The ink jet head according to claim 1, wherein said ink supply member is a resin member.