KR100756149B1 - Luquid-jet head and liquid-jet apparatus - Google Patents

Abstract

Provided are a liquid ejecting head and a liquid ejecting apparatus capable of placing each head body in close proximity and improving print quality.

A nozzle plate 20 provided with nozzle openings 21, a flow path forming substrate 10 in which a plurality of pressure generating chambers 12 are provided at the same time the nozzle plate 20 is joined to one surface side, and And a fixing plate 3 having a head main body 2 having at least a pressure generating means 300 and an exposure port 111 exposing the nozzle opening 21 to which the plurality of head main bodies 2 are positioned and fixed. The fixing plate 3 has a reservoir forming substrate 110 provided with a reservoir 112 and a compliance portion having a flexible portion 131 in a region facing the reservoir 112. The substrate 130 and the other side of the reservoir formation substrate 110 are bonded to each other so as to be formed of an encapsulation substrate 120 encapsulating the reservoir 112.

Description

Liquid jet head and liquid jet device {LUQUID-JET HEAD AND LIQUID-JET APPARATUS}

1 is an exploded perspective view of a recording head according to the first embodiment.

2 is a sectional view of a recording head according to the first embodiment.

3 is an enlarged cross-sectional view of the recording head according to the first embodiment.

4 is an exploded perspective view showing a modification of the recording head according to the first embodiment.

5 is a schematic diagram of an inkjet recording apparatus according to one embodiment.

<Description of the code>

1 inkjet recording head, 2 head body, 3 fixing plate, 4 flow path substrate, 10 flow path forming substrate, 12 pressure generating chamber, 20 nozzle plate, 21 nozzle opening, 22 ink supply port, 30 protection substrate, 31 piezoelectric element holder, 110 reservoir forming substrate, 111 exposed hole, 112 reservoir, 120 encapsulation substrate, 130 compliance substrate, 132 elastic sheet, 133 reinforcement substrate, 134 penetration, 135 ink supply communication port, 135 ink inlet

<Technology field>

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ejecting head and a liquid ejecting apparatus for ejecting a jetted liquid, and in particular, to a pressure generating means displacement for applying pressure to a liquid in a pressure generating chamber in communication with a nozzle opening for ejecting ink droplets. An ink jet recording head and an ink jet recording apparatus for ejecting ink droplets by means of an ink jet recording apparatus.

<Background technology>

An inkjet recording head, such as a printer or a plotter, is equipped with an inkjet recording head having a plurality of head bodies capable of discharging ink stored in an ink storage unit such as an ink cartridge or an ink tank as ink droplets.

In addition, such an inkjet recording apparatus generally discharges a plurality of ink droplets and color printing is performed. The inkjet recording apparatus has a plurality of head bodies each ejecting ink droplets of different colors. An inkjet recording head is mounted. As such an inkjet recording head (inkjet recording head unit), for example, each head main body (inkjet recording head) is positioned and fixed to a fixed plate provided on the nozzle plate side at predetermined intervals (example For example, refer patent document 1).

Moreover, each head main body communicates with the flow path formation board | substrate which consists of a silicon single crystal board | substrate, and the communication part which comprises a part of a pressure generating chamber and a reservoir is provided as described, for example in patent document 1 And a reservoir plate having a nozzle plate provided with a nozzle opening, a reservoir portion constituting the reservoir together with a communicating portion, and a piezoelectric element holding portion protecting the piezoelectric element.

In the head main body of such a structure, since a part of the reservoir is formed in the passage forming substrate together with the pressure generating chamber, the area of the flow passage forming substrate becomes large. For this reason, there also exists a problem that the inkjet type recording head in which the some head main body is provided also becomes large. Moreover, since the space | interval of each head main body becomes wider, ie, the space | interval of the row of nozzle openings becomes wider and a nozzle opening cannot be arranged in high density, there also exists a problem that the improvement of print quality becomes difficult. .

In addition, such a problem exists not only in the inkjet recording head which discharges ink but also of course in other liquid jet heads which discharge other than ink.

[Patent Document 1]

Japanese Patent Laid-Open No. 2005-096419 (claims of patent claims, first, fifth, etc.)

SUMMARY OF THE INVENTION In view of such circumstances, an object of the present invention is to provide a liquid jet head and a liquid jet device capable of arranging each head body in close proximity and improving print quality.

Means for solving the problem

According to a first aspect of the present invention, a nozzle plate provided with a nozzle opening for discharging a liquid drop and a plurality of pressure generating chambers connected to the nozzle opening while being bonded to one side of the nozzle plate are provided in parallel. The plurality of head bodies having a flow passage-forming substrate, a head body having at least pressure generating means for applying pressure to the liquid in the pressure generating chamber, and an exposure opening exposing the nozzle openings in regions corresponding to the head body, respectively. Is provided with a fixed plate to which the fixed position is fixed at a predetermined interval, and the fixed plate is bonded to one surface of the reservoir forming substrate and a reservoir in which a reservoir communicating with the plurality of pressure generating chambers is provided, and is opposed to the reservoir. A compliance board | substrate which has a flexible part deformable by the pressure change in this reservoir, and the said reservoir It is bonded to the other surface of the substrate side of the liquid-jet head characterized by comprising a sealing substrate for sealing the reservoir.

In this first aspect, the reservoir is provided on the fixed plate, and only the pressure generating chamber needs to be formed in the flow path formation substrate, so that the area of the flow path formation substrate is reduced and the head main body is miniaturized. In addition, with the miniaturization of the head body, the liquid jet head can be miniaturized. Moreover, the space | interval (interval of the row of nozzle opening) of each head main body can be narrowed. That is, since the nozzle openings can be arranged at high density, the print quality is improved.

According to a second aspect of the present invention, in the first aspect, the pressure generating chamber and the reservoir communicate with each other through a supply hole formed by a through hole provided in the compliance substrate and a plurality of micro holes provided in the nozzle plate. It is a liquid jet head characterized in that.

In this second aspect, bubbles can be prevented from mixing into the liquid, and the liquid can be satisfactorily supplied to each pressure generating chamber from the reservoir.

A third aspect of the present invention is the liquid jet head according to the first or second aspect, wherein the nozzle plate is made of a silicon single crystal substrate.

In this third aspect, the nozzle opening and the supply hole can be formed with high accuracy, and the discharge characteristic of the liquid droplets is improved.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the compliance substrate includes an elastic sheet made of an elastic material and a reinforcing substrate bonded onto the elastic sheet to fix the elastic sheet. A flexible part is formed with only the said elastic sheet, It is a liquid jet head characterized by the above-mentioned.

In this 4th aspect, the elastic sheet of a flexible part deform | transforms and the pressure in a reservoir is always kept constant.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a flow path for connecting the reservoir and the liquid holding means in which the liquid supplied to each reservoir is held in the region corresponding to the reservoir is provided on the fixed plate. A communication path constituting a part is provided, and a flow path member having a head holding portion is further joined to a region corresponding to each head main body.

In this fifth aspect, the liquid is satisfactorily supplied to each reservoir through the communication path of the flow path member. And the head main body becomes small, and the flow path member which has this communication path also becomes small.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the pressure generating means is a piezoelectric element provided on a surface on the side opposite to the nozzle plate of the flow path forming substrate via a diaphragm. It is a liquid jet head.

In this sixth aspect, liquid droplets are discharged from the nozzle opening by driving the piezoelectric element. In addition, since only the pressure generating chamber is formed in the flow path forming substrate, even if the structure having such a piezoelectric element is provided, no crack or the like occurs in the diaphragm.

7th aspect of this invention is a liquid ejection apparatus provided with the liquid ejection head of any one of 1st-6.

In this seventh aspect, it is possible to realize a liquid jetting apparatus which has improved reliability and has been miniaturized.

Preferred Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Below, this invention is demonstrated in detail based on embodiment.

(Embodiment 1)

1 is an exploded perspective view showing an inkjet recording head according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view showing the main part of the inkjet recording head.

As shown in FIG. 1, the inkjet recording head 1 according to the present embodiment includes a plurality of head bodies 2, a fixing plate 3 on which the head bodies 2 are fixed and positioned, and a head body ( It has the flow path board | substrate 4 joined with the fixed plate 3 with 2).

As shown in FIG. 2, the head main body 2 which concerns on this embodiment is a flow path formation board | substrate with a pressure generation chamber 12 to which pressure is applied by the drive of the piezoelectric element 300 which is an example of a pressure generation means ( 10), the nozzle plate 20 bonded to one surface of the flow path formation substrate 10, and the protective substrate 30 bonded to the surface of the piezoelectric element 300 side of the flow path formation substrate 10. .

Since the head main body 2 can eject ink by supplying ink and a drive signal, it is possible to perform ink ejection inspection in the form of the head main body 2. Therefore, when the head main body 2 is arranged in multiple numbers, it is a characteristic that the inkjet recording head with a small tolerance and high production rate can be obtained.

The flow path forming substrate 10 is made of a silicon single crystal substrate, and one side thereof is formed with an elastic film 50 made of silicon dioxide formed by thermal oxidation in advance. In this flow path formation substrate 10, heat in which the pressure generating chambers 12 partitioned by a plurality of partitions are arranged in the width direction by anisotropic etching from the other surface side thereof. Two rows are formed. The nozzle plate 20 is fixed to the opening surface side of the flow path formation substrate 10 through an adhesive agent, a heat welding film, or the like.

The nozzle plate 21 is provided with a nozzle opening 21 for discharging ink droplets, and each nozzle opening 21 has one end portion in the longitudinal direction of each of the pressure generating chambers 12, that is, the flow path forming substrate 10. It communicates with the edge part of the center side of the. Moreover, the ink supply port 22 which communicates with the edge part on the opposite side to the nozzle opening 21 of the pressure generating chamber 12 is provided in the nozzle plate 20. Then, ink is supplied to each of the pressure generating chambers 12 through this ink supply port 22 from a reservoir described later. The ink supply port 22 which concerns on this embodiment is comprised by the some micro hole. Although the size (diameter) of this micropore is not specifically limited, It is preferable that it is comparatively small, and it is preferable that it is smaller than the nozzle opening 21 at least.

As the material of the nozzle plate 20, it is preferable to use a material close to the flow path forming substrate 10 and the linear expansion coefficient. In the present embodiment, each nozzle opening 21 is formed using a silicon single crystal substrate. ) And the ink supply port 22 are formed by etching. Of course, the material of the nozzle plate 20 is not specifically limited, For example, you may use stainless steel (SUS), In this case, each nozzle opening 21 and the ink supply port 22, What is necessary is just to form by press working.

On the other hand, an insulator film 55 made of, for example, zirconium oxide (Zr02) or the like is provided on the elastic film 50 on the side opposite to the opening surface of the flow path forming substrate 10, and the insulator film 55 is provided. Above, for example, a lower electrode film 60 made of a metal material such as platinum or iridium, a piezoelectric layer 70 made of a piezoelectric material such as lead zirconate titanate (PZT), and an example. For example, the upper electrode film 80 made of a metal material such as iridium is stacked, and the piezoelectric elements 300 are formed in regions facing the pressure generating chambers 12, respectively. In addition, here, the piezoelectric element 300 and the diaphragm which a displacement generate | occur | produces by the drive of this piezoelectric element 300 are combined, and it is called an actuator.

Moreover, the lead electrode 90 is connected to the upper electrode film 80 which is an individual electrode of each piezoelectric element 300, respectively. In this embodiment, one end of the lead electrode 90 extends along the longitudinal direction of the piezoelectric element 300 to the center of the flow path forming substrate 10, and the tip thereof is a protective substrate which will be described later. It is exposed in the penetrating portion 32 of 30.

A protective substrate 30 having a piezoelectric element holding part 31 for protecting the piezoelectric element 300 is bonded to the surface of the flow path forming substrate 10 on the piezoelectric element 300 side through an adhesive or the like. In this embodiment, the piezoelectric element holding part 31 is provided independently in the area | region which opposes the column of each piezoelectric element 300, respectively. Since the piezoelectric element 300 is formed in this piezoelectric element holding part 31, it is protected by the state which is hardly influenced by an external environment. In addition, although the piezoelectric element holding part 31 may be sealed, it does not need to be sealed, of course.

Here, the protective substrate 30 may be bonded to the flow path forming substrate 10 in a region formed only of the diaphragm, that is, a region in which an ink flow path is formed, in the bonding area of the flow path forming substrate 10 with the protective substrate 30. In such a case, there is a problem that splitting occurs in the diaphragm in the region. However, in the structure of this invention, since only the pressure generation chamber 12 is formed in the flow path formation board | substrate 10, and the ink flow path is not formed in the bonding area | region with the protection board | substrate 30, such a problem does not arise. .

Moreover, the penetrating part 32 which penetrates the protection board 30 in the thickness direction is provided in the center part of the protection board 30, ie, the area | region corresponding between the columns of the piezoelectric element 300. As shown in FIG. And as mentioned above, the lead electrode 90 corresponding to each piezoelectric element 300 extends to the area | region which opposes this penetration part 32, respectively, Although it is not shown in figure, this penetration part 32 It is electrically connected with the drive IC etc. for driving the piezoelectric element 300 through the connection wiring extended in the inside. Examples of the material of the protective substrate 30 include glass, ceramics, metals, plastics, and the like, but it is preferable to use a material substantially the same as the thermal expansion coefficient of the flow path forming substrate 10. For this reason, in this embodiment, the silicon single crystal substrate of the same material as the flow path formation substrate 10 is used as the material of the protective substrate 30.

The plurality of head main bodies 2 and the three head main bodies 2 of this configuration are positioned and joined to the fixed plate 3 at predetermined intervals. Moreover, in this embodiment, the flow path board | substrate 4 is joined to the fixed board 3 with these some head main bodies 2 (refer FIG. 1).

Here, the fixing plate 3 according to the present invention is composed of a reservoir forming substrate 110, an encapsulation substrate 120, and a compliance substrate 130, and a region corresponding to the nozzle opening 21 of each head body 2. An exposure port 111 is provided in the reservoir formation substrate 110, the encapsulation substrate 120, and the compliance substrate 130 to expose the nozzle openings 21. Moreover, it is preferable that the opening edge on the opposite side to the head main body 2 of this exposure port 111, ie, the opening edge on the side of the sealing substrate 120, is made of the chamfered tapered surface 111a (Fig. 3). Reference). In order to smooth the wiping of the surface of the nozzle opening 21.

The reservoir formation substrate 110 is made of, for example, a material such as a silicon single crystal substrate, and corresponds to the heat of the pressure generating chambers 12 to allow the reservoir 112 to penetrate the reservoir formation substrate 110 in the thickness direction. Has Then, an encapsulation substrate 120 made of a material such as a silicon single crystal substrate is bonded to one surface of the reservoir forming substrate 110, that is, the surface opposite to the head main body 2, thereby joining. The surface of one side of the reservoir 112 is sealed.

The compliance substrate 130 is bonded to one surface side of the reservoir formation substrate 110, and a flexible portion 131 that is deformable by a pressure change in the reservoir 112 is provided in a region corresponding to the reservoir 112. have. As the flexible portion 131 deforms, the pressure change in the reservoir 112 is substantially absorbed, and the inside of the reservoir 112 is always maintained at a substantially constant pressure.

In this embodiment, the compliance board | substrate 130 consists of an elastic sheet 132 which consists of elastic materials, such as a resin material, and the reinforcement board | substrate which consists of stainless steel (SUS) etc., and reinforces the elastic sheet 132 ( 133, and the elastic sheet 132 side is bonded to the reservoir formation substrate 110. In the region facing the reservoir of the reinforcing substrate 133, a penetrating portion 134 penetrating the reinforcing substrate 133 in the thickness direction is formed, and only the elastic sheet 132 is formed in the penetrating portion 134. It becomes the flexible part 131.

In addition, an ink supply communication port 135 through which one end communicates with the reservoir 112 and the ink supply port 22 of the nozzle plate 20 communicates with the other end side is formed in the compliance substrate 130. . And the reservoir 112 provided in the reservoir formation board | substrate 110 is the pressure of each head main body 2 through this ink supply communication port 135 and the ink supply port 22 provided in the nozzle plate 20. FIG. It communicates with the generation chamber 12, respectively.

In addition, although the ink supply communication hole 135 may be provided independently for every pressure generation chamber 12, in this embodiment, it is formed in the shape of a slit, and is common to the several pressure generation chamber 12. It is. Since the ink supply ports 22 provided in the nozzle plate 20 are provided independently for each of the pressure generating chambers 12, even if the ink supply communication holes 135 have a slit shape, they are provided in the pressure generating chambers 12, respectively. Ink is preferably supplied. The compliance substrate 130 is further provided with an ink inlet 136 for supplying ink into the reservoir 112. The number of the ink inlets 136 is not particularly limited, but in the present embodiment, two ink inlets 136 are provided corresponding to the respective reservoirs 112.

On this compliance substrate 130, one end of the flow path has an ink communication path 4a connected to the ink inlet 136 and the other end connected to an ink holding means (not shown) such as an ink cartridge. The board | substrate 4 is joined. The flow path substrate 4 which concerns on this embodiment has the head holding part 4b which penetrates the flow path substrate 4 in the thickness direction in the area | region corresponding to each head main body 2, It is installed so as to surround the surroundings. The flow path substrate 4 is provided with ink communication paths 4a at positions corresponding to the ink introduction ports 136 of the compliance substrate 130, respectively, and the ink communication paths 4a and the ink introduction ports ( The ink in the ink holding means is supplied to the reservoir 112 through 136.

As described above, in the present invention, only the pressure generating chamber 12 is formed in the flow path forming substrate 10 of the head main body 2, and the reservoir (3) is fixed to the fixed plate 3 on which the plurality of head main bodies 2 are fixed. 112). As a result, the area of the flow path formation substrate 10 is reduced, and the actuator formed on the flow path formation substrate 10 is downsized, so that a significant cost reduction can be achieved. That is, by reducing the area of the actuator part which is expensive in manufacturing cost, it becomes a significant cost reduction for a head.

Moreover, the head main body 2 is also miniaturized by decreasing the area of the flow path formation substrate 10. Therefore, the arrangement pitch of each head main body 2 can be narrowed, and the space | interval of the row of each nozzle opening 21 also becomes narrow. That is, the nozzle opening 21 can be arrange | positioned at high density, and print quality improvement can also be aimed at.

(Other embodiment)

As mentioned above, although embodiment of this invention was described, this invention is not limited to what was mentioned above. For example, in the above-described embodiment, the head body is arranged in a direction orthogonal to the column direction of the pressure generating chamber 12. However, the embodiment is not limited thereto. For example, as shown in FIG. A plurality of head main bodies 2 may be provided in the column direction of the pressure generating chamber 12. In this case, the fixing plate 3 may be provided with the reservoir 112A common to the plurality of head bodies 2. In addition to the reservoir 112A, the penetrating portion 134A, that is, the flexible portion 131A, of the reinforcing substrate 133 may be continuously formed over the regions corresponding to the plurality of head bodies 2. . Of course, even when it is set as such a structure, the pitch of each head main body 2 can be narrowed. Therefore, the effect that the inkjet recording head can be miniaturized and the print quality can be improved can be obtained.

Moreover, although the bending vibration type piezoelectric element was illustrated as a pressure generating means which applies pressure to the liquid in the pressure generating chamber 12 in the above-mentioned embodiment, a pressure generating means is not specifically limited, For example, piezoelectric It may be a longitudinal vibration type piezoelectric element which alternately laminates the material and the electrode forming material and expands and contracts in the axial direction, or may be a heating element or the like.

In addition, the inkjet recording head 1 of the above-mentioned embodiment forms a head unit together with the holding member on which liquid holding means, such as an ink cartridge, is mounted, for example, and is mounted in an inkjet recording apparatus. 5 is a schematic view showing an example of an inkjet recording apparatus. As shown in FIG. 5, the head unit 200 having the inkjet recording head 1 is mounted on the carriage 202 in a state where a plurality of ink cartridges 201 are detachably fixed. As for the carriage 202 which mounts the head unit 200, the axial movement is provided in the carriage shaft 204 attached to the apparatus main body 203 freely.

The carriage 202 mounted with the head unit 200 is transmitted to the carriage 202 via a plurality of cogs and timing belts 206 in which the driving force of the drive motor 205 is not shown. Is moved along the carriage shaft 204. On the other hand, a platen 207 is provided along the carriage shaft 204 in the apparatus main body 203, and a recording sheet S, which is a recording medium such as paper fed by a feeding roller or the like, is not shown. The platen 207 is conveyed.

In addition, in the above-described embodiment, the inkjet recording head for discharging ink as the liquid jet head has been described as an example, but the present invention broadly covers the liquid jet head and the entire liquid jet apparatus. As the liquid jet head, for example, a color material jet head used for the production of color filters such as a liquid crystal display, an electrode material jet head used for forming electrodes such as an organic EL display, a FED (surface light emitting display), and a biochip production The bio organic substance injection head etc. which are used are mentioned.

As described above, according to the present invention, since the reservoir is provided on the fixed plate and only the pressure generating chamber is formed in the flow path forming substrate, the area of the flow path forming substrate is reduced and the head main body can be miniaturized. In addition, with the miniaturization of the head body, the liquid jet head can be miniaturized. Moreover, the space | interval (interval of the row of nozzle opening) of each head main body can be narrowed. That is, since the nozzle openings can be arranged at high density, the print quality is improved.

Claims (7)

A nozzle plate provided with a nozzle opening for discharging a liquid drop, a flow path forming substrate in which a plurality of pressure generating chambers are connected to the nozzle opening while the nozzle plate is joined to one surface side, and the pressure generating chamber A head body having at least a pressure generating means for applying pressure to the liquid in the liquid and an exposure opening exposing the nozzle opening in each of the regions corresponding to the head body, the plurality of head bodies being positioned and fixed at predetermined intervals. With a fixed plate, This fixed plate is deformable due to a pressure change in the reservoir in a reservoir-forming substrate provided with a reservoir communicating with a plurality of the pressure generating chambers, and a region bonded to one surface of the reservoir-forming substrate and opposed to the reservoir. A liquid ejection head comprising: a compliance substrate having a flexible portion; and an encapsulation substrate bonded to the other surface of the reservoir forming substrate to seal the reservoir. The method of claim 1, The pressure generating chamber and the reservoir communicate with each other through a supply hole formed by a through hole provided in the compliance substrate and a plurality of micro holes provided in the nozzle plate. The method of claim 1, And the nozzle plate is made of a silicon single crystal substrate. The method of claim 1, The compliance substrate is composed of an elastic sheet made of an elastic material and a reinforcing substrate bonded to the elastic sheet to fix the elastic sheet, wherein the flexible part is formed of only the elastic sheet. The method of claim 1, On the fixing plate, a communication path constituting a portion of a flow path connecting the reservoir and the liquid holding means holding the liquid supplied to each reservoir is provided in an area corresponding to the reservoir, and at the same time the head is located in the area corresponding to each head body. A flow passage member having a holding portion is further joined. The method of claim 1, And the pressure generating means is a piezoelectric element provided on a surface on the side opposite to the nozzle plate of the flow path forming substrate via a diaphragm. A liquid ejecting device comprising the liquid ejecting head of claim 1.

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