JP2000351213A - Ink jet head and ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and correctly control a deformation volume of a shape memory alloy by reproducing a shape memorized by a shape memory material part, deforming part of a wall, reducing a volume in a space, and increasing to restore the volume by a restoring force of a spring material when the deformation is released. SOLUTION: In an ink jet head 2, when an ink 24 of a common ink chamber 10 is filled to selected ink channels 8 via each ink inlet 14 and a predetermined voltage is impressed from a driving circuit 26 to a pair of electrodes 24, a corresponding SMA film form part 18 heats and transforms from a martensite phase to a mother phase when it reaches a transformation temperature, with deforming a part of a diaphragm plate 6 to a protrusion shape, whereby the ink 24 is pressured and discharged. Then, when the voltage impression finishes, the SMA film form part 18 finishes heating to be an ordinary temperature and is restored by a restoring force of a spring material to a state before the voltage impression. The diaphragm plate and SMA are curved at high temperatures, a shape of which is memorized. The diaphragm plate and SMA can be joined when the diaphragm plate is flat.

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, and more particularly to an ink jet head used for an ink jet printer for forming an image by flying ink.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 6-91865 discloses an ink jet head using a shape memory alloy. In this inkjet head, as shown in FIGS. 12 and 13, a plurality of grooves (that is, ink chambers 201) are formed by processing the surface of the substrate. Ink chamber 20
1 is a first regulating layer 203 and the first regulating layer 203
And a second regulating layer 202 fixed thereon. Here, the second restriction layer 202 is formed of a shape memory alloy. Further, the second regulating layer 202 made of a shape memory alloy is curved toward the outside of the ink chamber 201 in a normal temperature state (martensite phase).

In an ink-jet head employing such a configuration, when a voltage is applied to the regulating plate 204 and heated, the second regulating layer 202 made of a shape memory alloy is transformed from a martensite phase to a parent phase, As shown by a dotted line in FIG. 12, the state changes from a curved state to a flat state. As a result, the ink contained in the ink chamber 201 flies through the nozzle 207 formed on the substrate.

[0004]

However, this ink jet head has the following problems. As described above, the second restriction layer 202 made of a shape memory alloy takes a curved shape at normal temperature (martensite phase) and has a flat shape at high temperature (mother phase). However, actually, it is not easy to memorize such a transformation in a shape memory alloy. In order to increase the resolution of an image to be formed, the distance between the nozzles 207 must be narrowed to increase the number of nozzles 207. Then, the regulating plate 204 needs to be formed in a more elongated shape, and it becomes difficult to curve the regulating plate 204 at room temperature. The configuration in which the regulating plate 204 is bent at room temperature cannot avoid instability. In addition, variations in the amount of unevenness and the like are likely to occur depending on the position of the regulating plate 204, and the accuracy of the amount of flying ink is likely to be lacking.

In view of the above, the present invention provides an ink jet head using a shape memory alloy, in which the shape memory of the shape memory alloy is easy, an appropriate deformation volume can be obtained even if the nozzle interval is small, and the deformation volume of the shape memory alloy can be accurately determined. It is an object of the present invention to provide an ink jet head that can be controlled at a low speed.

[0006]

In order to achieve these objects, an ink jet head according to the present invention has a structure in which at least a part of a wall forming a space for accommodating ink is made of a resilient spring material. Further, a portion made of a shape memory material is joined to the spring material, and the portion made of the shape memory material stores a shape other than a planar shape.
Here, by reproducing the shape stored in the portion made of the shape memory material, a part of the wall is deformed to reduce the volume in the space, and the deformation of the portion made of the shape memory material is performed. Is released, the volume in the space increases and recovers due to the restoring force of the spring material.

An ink jet head according to another embodiment of the present invention and an ink jet recording apparatus provided with the ink jet head have a nozzle for connecting the space with the atmosphere. Therefore, the ink is pressurized due to the decrease in the volume in the space, thereby discharging the ink to the atmosphere via the nozzle.

[0008]

According to the ink jet head and the ink jet recording apparatus configured as described above, the shape memory of the shape memory alloy is easy, and an appropriate deformation volume can be obtained even if the nozzle interval is small. An ink jet head that accurately controls the volume, that is, the amount of flying ink, can be provided.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION First, an inkjet head according to a first embodiment of the present invention will be described with reference to the accompanying drawings. 1 and 2, an ink jet head 2 according to the present invention is generally composed of two members—a channel plate 4 and a vibration plate 6—. The channel plate 4 is formed of a plate having a predetermined thickness, and has a plurality of ink channels 8 formed in parallel. The ink channel 8 is an elongated groove having a predetermined depth, which is formed on one surface of the channel plate 4 as shown in FIGS. In this embodiment, only three ink channels 8 are formed in one channel plate 4, but more (eg, several hundred) ink channels 8 may be formed.
At a predetermined distance from one end in the longitudinal direction of these ink channels 8, a common ink chamber 1 is provided in the channel plate 4.
0 is formed. The common ink chamber 10 is a recess having a predetermined depth on the same surface as the ink channel 8. Each ink channel 8 is provided in the common ink chamber 10.
In order to connect the ink channels 8 and the common ink chamber 10 on the same surface of the channel plate 4, grooves (ink inlets 14) corresponding to the respective ink channels 8 are provided.
Are formed. And a back surface of the channel plate 4 on which the ink channels 8 are formed,
In addition, near one end in the longitudinal direction of the ink channel 8 and another end connected to the common ink chamber 10, one or more lines in a direction substantially orthogonal to the longitudinal direction of the ink channel 8 are arranged. The nozzles 16 are formed one by one corresponding to each ink channel 8.

The channel plate 4 is preferably made of a material having high rigidity. For example, a plate made of metal such as stainless steel, silicon, glass, ceramics or the like can be used. As for the ink channel 8 and the ink inlet 14, it is desirable to first form the ink inlet 14, and then form the ink channel 8 by etching or the like. Further, in order to form a high-density (high-resolution) inkjet head 2 by narrowing the interval between adjacent ink channels 8 and to form a side wall having a high aspect ratio (width / height), for example, a silicon substrate is used. It is preferable to form the ink channel 8 and the like by anisotropic etching. In this case, the etching is performed in two stages, one of which forms the ink channel 8 and the other of which forms the ink inlet 14.
To form However, the processing of the channel plate 4 is not limited to etching, for example, sand blast,
Dicing, RIE (reactive ion etching), or the like may be used. In the case where the channel plate 4 is formed of photosensitive glass, photolithography can be used in addition to these methods.

The nozzle 6 is formed by an appropriate method such as etching, sandblasting, or photolithography depending on the material.

The vibrating plate 6 is a thin plate having a thickness of about 1 to several μm, and is made of, for example, silicon oxide (SiO ₂ ) or polysilicon, which has a strong restoring force as a spring material. As shown in FIG. 1 and FIG. 2A, a shape memory alloy (SMA) such as a TiNi alloy, an alloy obtained by adding Pd or Cu to TiNi, or a Cu—Zn—Al alloy is provided on one surface of the vibration plate 6. Are formed and patterned. The SMA film forming section 18 is spaced at the same distance as the distance between the ink channels 8 formed on the channel plate 4, has substantially the same size as the ink channels 8, and corresponds to each ink channel 8. Each one is formed (film formation and patterning). The SMA film forming unit 18 does not need to be formed of a metal,
Shape memory resin, shape memory fiber, or a composite material thereof may be used. Note that TiNi alloys have different characteristics (especially transformation temperature) depending on their composition. For example, those having a composition ratio of Ti and Ni of 51% -49% and a transformation temperature of about 70 ° C. can be suitably used. In the case of the TiNi alloy having this composition, the maximum strain is about 5% and the generated stress is about 600 MPa. This vibrating plate 6, as shown in FIGS.
Each SMA film forming unit 18 faces the ink channel 8 with the vibration plate 6 interposed therebetween, and the common ink chamber 10
Is placed on one surface of the channel plate 4 so that the channel plate is closed by, and is adhered to the channel plate 4 by, for example, an adhesive.

The vibration plate 6 is bonded to the SMA film forming section 1
8 martensite phase below SMA transformation temperature (normal temperature)
(FIG. 3A). Thereafter, the SMA film forming section 18 is pressed while the ink channel 8 including the SMA film forming section 18 is pressed using a heat-resistant convex jig (heat-resistant pressing jig) 20.
Is subjected to an annealing (shape memory) operation (see FIG. 3).
(2)). The heat resistant pressing jig 20 is made of, for example, titanium, zirconium, Si, butterfly steel, alumina ceramic, or the like. The annealing operation is a known technique in the related art, and is performed for a predetermined time while controlling the atmospheric pressure and the temperature inside an annealing chamber (not shown). These conditions (annealing conditions) at the time of annealing may be, for example, if SMA is a TiNi alloy: Atmospheric pressure: 5 × 10 ⁻⁷ Torr (Torr); Temperature: 550 ° C .;

In the heat-resistant pressurizing jig 20, the convex portion 22
The same number of ink channels 8 and SMA film forming sections 18 are formed in correspondence with those. In particular, individual S
The convex portion 22 is formed so as to press substantially the entire MA film forming section 18 (FIG. 3B). As will be described later, in order to appropriately obtain a change in the volume of the ink channel 8,
The shape of the protrusion 22 of the heat-resistant pressing jig 20 can be arbitrarily selected. 5 (1), (2), (3),
(4) is an example of the shape of the protrusion 22.

After the annealing operation, the annealing conditions are released, the heat-resistant pressurizing jig 20 is released, and the inkjet head 2 is taken out of the annealing chamber. Then, due to the restoring force of the spring material of the vibration plate 6, the vibration plate 6 is restored to a state substantially before the annealing operation (FIG. 3C). Also, as shown in FIG.
Electrodes 24 are provided at both ends in the longitudinal direction of each SMA film forming unit 18, and these electrodes 24 are connected to a drive circuit 26.

In the ink jet head 2 configured as described above, the ink 24 is supplied to the common ink chamber 10 by a mechanism (not shown). The ink 24 is further supplied to and filled in the corresponding ink channel 8 via each ink inlet 14 as shown in FIG.
In this state, when a predetermined voltage (pulse voltage) is applied from the drive circuit 26 to the pair of electrodes 24 corresponding to the selected ink channel 8, the corresponding SMA film forming section 18 becomes a resistor and generates heat. . Then, the SMA film forming unit 1
When the SMA of No. 8 reaches the transformation temperature, the SMA transforms from the martensite phase to the parent phase, and as shown in FIG. Deforms convex. As a result, the ink 24 in the corresponding ink channel 8 is pressurized, and the ink 24 is ejected from the corresponding nozzle 16. Next, when the voltage application by the drive circuit 26 is completed, the heat generation of the SMA film forming unit 18 ends, and the SMA film forming unit 18 is brought to a normal temperature state. As a result, the SMA film forming section 18 is transformed from the mother phase to the martensite phase, and is restored to a state before heating, that is, a state before voltage application (FIG. 4A) by a restoring force of the spring material of the vibration plate 6. At this time, a negative pressure is generated in the ink channel 8,
The ink 24 is replenished from the common ink chamber 10 via the ink inlet 14 by the suction force.

As described above, according to the ink jet head 2 of the present invention, the vibrating plate and the SMA are curved at a high temperature to store the shape, and the two are joined (ie, the SMA is joined).
Film formation and patterning) are performed when the vibrating plate has a flat and stable shape, so that shape memory and joining operations can be easily performed. In addition, in order to reliably anneal SMA under annealing conditions using a heat-resistant pressurizing jig, SM
There is no variation in the amount of unevenness or the like when A is curved, so that the accuracy of the amount of ink that flies increases.

In the above embodiment, the SMA film forming section 1
8, a transformation from the martensite phase to the parent phase is caused by the Joule heat generated by the film forming unit 18 itself, but a resistor is disposed in contact with the film forming unit 18 and a voltage is applied to the resistor. It may be configured to do so. Further, heat may be directly applied to the SMA film forming unit 18 by a heater. In order to return the heated SMA film forming section 18 to the initial state as quickly as possible, a mechanism (either an air cooling mechanism or a water cooling mechanism) for cooling the SMA film forming section 18 may be provided.

2. Next, an ink jet head according to a second embodiment of the present invention will be described with reference to FIGS. 6, 7, and 8. FIG. In FIG. 6, the ink jet head 32 according to the present invention is also generally composed of two members: a channel plate 34 and a vibration plate 36. The channel plate 34 is formed of a plate having a predetermined thickness, and has ink channels 38 formed therein. The ink channel 38 is formed on one surface of the channel plate 34 as shown in FIG.
The groove has a predetermined depth. In this embodiment, only one ink channel 38 is formed, but more (for example, several hundred) ink channels 38 may be formed. Then, on one side surface of the channel plate 34, (in this embodiment, three) nozzles 46 are formed. This channel plate 34 is, as shown in FIG.
The channel plate 4 according to the first embodiment of the inkjet head 2 shown in FIG. 2 is formed using the same material and technology.

In the vibration plate 36, FIGS.
May be substantially the same as the vibration plate 4 according to the first embodiment of the inkjet head 2 shown in FIG. Further, similarly, the plurality of elongated SMA film forming sections 48
It is formed (film formation and patterning) on the top.

Next, while the vibration plate 36 including the SMA film forming section 48 is pressed and constrained using the heat-resistant jig 50, the SM
The annealing (shape memory) operation is performed on the A film forming section 48. In this embodiment, the heat-resistant jig 50 is the same as that shown in FIG.
It has a cylindrical shape as shown in FIG. The heat-resistant jig 50 is pressed against the vibrating plate 36 so that the longitudinal direction of the plurality of SMA film forming sections 48 goes around the cylindrical curved surface, and annealing is performed while the vibrating plate 36 is restrained in the shape of FIG. . At this time, the heat-resistant jig 50 is pressed against the vibration plate 36 so that the SMA film forming section 48 is in contact with the heat-resistant jig 50.
The “annealing conditions” are the same as the annealing conditions for the vibration plate 6 and the SMA film forming unit 18 according to the first embodiment of the inkjet head 2 in FIG. Further, the heat resistant pressing jig 50 is also the heat resistant pressing jig 2 of the first embodiment of FIG.
As in the case of 0, titanium, zirconium, Si, butterfly steel, alumina ceramic, or the like is used as the material.

After the annealing operation, the vibrating plate 36 restored to the state before the annealing operation is substantially restored by the restoring force of the spring material.
As shown in FIG. 6, it is bonded to the channel plate 34 by, for example, an adhesive. The bonding of the vibration plate 36 is performed by SM
This is performed in a martensite phase (normal temperature) equal to or lower than the SMA transformation temperature of the A film forming section 48. Although not shown, each S
Electrodes are also provided at both ends in the longitudinal direction of the MA film forming section 48, and these electrodes are connected to a drive circuit (not shown).

The ink jet head 32 configured as described above is moved by the mechanism (not shown) to the ink channel 3.
8 is supplied and filled with ink 24 (FIG. 8).
(1)). In this state, when a predetermined voltage (pulse voltage) is applied from a drive circuit (not shown) to the electrodes (not shown), the corresponding SMA film forming section 48 becomes a resistor and generates heat. Then, when the SMA of the SMA film forming section 48 reaches the transformation temperature, the SMA transforms from the martensite phase to the parent phase, and as shown in FIG.
Further, the portion of the vibrating plate 36 immediately therebelow is deformed in a convex shape downward in the drawing. Accordingly, the ink 24 in the ink channel 38 is pressurized, and the ink 24 is ejected from the nozzle 46. Next, when the voltage application by the drive circuit ends, SM
The heat generation of the A film forming unit 48 ends, and the SMA film forming unit 48 is brought to a normal temperature state. As a result, the SMA film forming section 48 is transformed from the mother phase to the martensite phase, and is restored to a state before heating, that is, before voltage application (FIG. 8A) by the restoring force of the spring material of the vibration plate 36. At this time, ink channel 3
8, a negative pressure is generated, and the ink 24 is replenished by the suction force. Note that there are various methods for heating the SMA film forming unit 48, similarly to the method for heating the SMA film forming unit 18 in the first embodiment.

3. Ink Jet Head of Third Embodiment Further, FIGS. 9 and 10 show a third embodiment of the ink jet head of the present invention. In the ink channel 68 of the ink jet head 62 according to the third embodiment, the SMA is provided outside the side wall 69 of the ink channel 68.
(For example, TiNi alloy) 78 is formed (FIG. 9)
(1)). Using a heat-resistant jig 80 (made of titanium, zirconium, Si, butterfly steel, alumina ceramic, or the like) as shown in FIG. 9B, as shown in FIG.
Annealing is performed while expanding and pressing the side wall 69 on which the SMA film is formed. When the temperature is returned to normal temperature and the heat-resistant pressurizing jig 80 is removed and taken out of the annealing chamber (not shown), the shape is substantially equal to the shape before annealing due to the restoring force of the side wall 69 (made of SiO ₂ or polysilicon). Restore (Fig. 9
(4)). Then, a plate 66 made of glass or the like is bonded by a known technique such as anodic bonding so as to cover the entire ink channel 68 (FIG. 9 (5)).

The ink jet head 62 having the above-described configuration is moved by the mechanism (not shown) to the ink channel 6.
8 is supplied with ink 24 and filled (see FIG. 10).
(1)). From this state, the SMA film forming section 78 is heated by an appropriate mechanism. When the SMA of the SMA film forming section 78 reaches the transformation temperature, the SMA transforms from the martensite phase to the parent phase, and as shown in FIG. 10 (2), the SMA film forming section 78 and the ink channel 68 near the SMA film forming section 78. The side wall 69 is deformed in a convex shape inside the ink channel 68. Accordingly, the ink 24 in the ink channel 68 is pressurized, and the ink 24 is ejected from a nozzle (not shown). Next, the heating of the SMA film forming unit 78 is completed and the SMA film forming unit 7 is completed.
When 8 transforms from the parent phase to the martensite phase (normal temperature),
By the restoring force of the spring material of the ink channel 68 side wall 69, the ink channel 68 is restored to the state before the heating (FIG. 10A). At this time, a negative pressure is generated in the ink channel 68, and the ink 24 is replenished by the suction force.

4. Embodiment of Printer FIG. 11 shows a part of a printer 100 incorporating the ink jet head 2 of the first embodiment. The printer 100 has a bottom plate 102, a pair of support walls 104 extending substantially perpendicularly from the bottom plate 102 and facing each other, and a front wall 106 connecting the support walls 104. Front wall 106
A sheet feed tray 108 for storing sheets (paper) S to be printed by the printer 100 is provided on the outside of the front side. The sheets S stored in the sheet feed tray 108 are formed on the front wall 106. Through a paper feed port (not shown)
It is supplied to the inside of the printer 100.

Inside the front wall 106, a pair of support walls 10
4, an upper guide rail 112 parallel to the front wall 106 and a lower guide rail 114 disposed below the upper guide rail 112 are supported. On these guide rails 112 and 114, an ink cartridge 116 is movably supported. Insert the ink cartridge 116 into the guide rails 112 and 114
The scanning mechanism 118 that reciprocates along a pair of the pulleys 120 supports a pair of pulleys 120 supported inside the front wall 106 near the respective support walls 104 and a belt 122 wound around these pulleys 120. And a motor (not shown) for rotating the pulley 120 forward and reverse.
An ink cartridge 11116 is connected to a part of the second cartridge 2.

In the present embodiment, the ink cartridge 116 has one or a plurality of the above-described ink jet heads 10 on the lower surface thereof. Ink cartridge 116
A sheet guide 124 is provided below and at a distance from the inkjet head 10. This seat guide 1
24, a sheet feeding roller 128 for conveying the sheet S fed into the printer 100 through the sheet feeding port of the front wall 106 in the direction of arrow 126 (conveying direction).
Are arranged in a direction perpendicular to the paper feeding direction, and are rotatably supported by the opposing support wall 104. Further, on the downstream side of the ink cartridge 116 with respect to the sheet feeding direction, a pressing roller 130 for pressing the sheet S against the sheet guide 124 is arranged in a direction orthogonal to the sheet feeding direction.

The paper feed roller 128 has a gear 134 fixed to a shaft 132 and a support wall 10 near the gear 134.
4 is connected to a motor 138 via a gear 136 rotatably supported by the motor 4, and the sheet feed roller 128 rotates based on the rotation of the motor 138 to convey the sheet S in the direction of arrow 126. It is.

At the time of printing by the printer 100 configured as described above, the sheet S sent from the sheet feeding tray 108 is printed.
Is fed into the printer 100 through the paper feed port of the front wall 106. Next, the sheet S is conveyed in the direction of arrow 126 along the sheet guide 124 by the sheet feeding roller 128 that rotates based on the driving of the motor 138. Further, the sheet S moving on the sheet guide 124 is pressed against the sheet guide 124 by the pressing roller 130,
Thereby, the interval between the sheet S and the ink head 10 is kept constant.

In synchronization with the movement of the sheet S, the ink cartridge 116 reciprocates along the guide rails 112 and 114 by the rotation of the belt 122, and
The ink is ejected from the ink jet head 10 to the portion of the sheet S that moves on the top 24 and printing is performed. The printed sheet S is discharged onto a discharge tray (not shown).

[Brief description of the drawings]

FIG. 1 is an exploded perspective view (and a partially transparent view) of an inkjet head according to a first embodiment of the present invention.

FIG. 2 is a partial plan view of the inkjet head of FIG. 1, (2) a side sectional view related to the AA section, and (3) a B-
It is a partial side sectional view concerning a B section, and (2) a partial side sectional view concerning a CC section (however, it is upside down with the sink jet head shown in Drawing 1, Drawing 3, and Drawing 4). ).

FIG. 3 is a partial side sectional view of the inkjet head of FIG. 1; However, (2) includes a pressing jig.

FIG. 4 is a partial sectional side view of the inkjet head of FIG. 1;

FIG. 5 is a cross-sectional view of a shape example of a pressurized portion (convex portion) of a pressurizing jig used for storing a shape in a shape memory material.

FIG. 6 is an exploded perspective view of an inkjet head according to a second embodiment of the present invention.

FIG. 7 shows a pressurizing jig used for storing a shape of a vibration plate in an ink jet head according to a second embodiment of the present invention, and a vibration plate having a shape stored therein.
It is a perspective view.

FIG. 8 is a side sectional view of the inkjet head according to the second embodiment of the present invention, taken along the line DD (FIG. 6);
(1) is at the time of ink filling, and (2) is at the time of heating the shape memory material.

FIG. 9 is a partial cross-sectional view mainly showing formation of a shape memory of an ink channel portion of an ink jet head according to a third embodiment of the present invention.

FIG. 10 is a partial cross-sectional view mainly showing an operation of an ink channel portion of an ink jet head according to a third embodiment of the present invention.

FIG. 11 is a partial perspective view of a printer incorporating an ink jet head according to the present invention.

FIG. 12 is a sectional view of a conventional inkjet head.

FIG. 13 is a plan view of a conventional inkjet head.

[Explanation of symbols]

 2, 32 ... Inkjet head 4, 34, 64 ... Channel plate 6, 36 ... Vibration plate 8, 38, 68 ... Ink channel 10 ... Common ink chamber 14 ... Ink inlet 16 , 46 ... Nozzle 18, 48, 78 ... SMA film forming part 20, 50, 80 ... Heat resistant pressing jig 26 ... Drive circuit 69 ... Side wall

Claims (4)

[Claims] At least a part of a wall forming a space for accommodating ink is made of a spring material having a restoring force, and a part made of a shape memory material is joined to the spring material. The portion made of the material memorizes a shape other than the planar shape, and by reproducing the shape memorized by the portion made of the shape memory material, a part of the wall is deformed to increase the volume in the space. When the deformation of the portion made of the shape memory material is released,
An ink jet head wherein the volume in the space is increased and recovered by the restoring force of the spring material. 2. The ink jet printer according to claim 1, further comprising a nozzle for connecting the space to the atmosphere, wherein the ink is pressurized by reducing the volume in the space, thereby discharging the ink to the atmosphere via the nozzle. The ink jet head according to claim 1, wherein 3. An ink jet recording apparatus comprising the ink jet head according to claim 2. 4. A flat spring material having a restoring force,
At least a part of a wall forming a space for accommodating ink is formed, and a planar shape portion made of a shape memory material is joined to the planar shape spring material, and a planar shape portion is formed on the portion made of the shape memory material. A method of manufacturing an ink jet, which stores a shape other than the shape memory material, and reduces a volume in the space by deforming a part of the wall by reproducing a shape stored in a portion made of the shape memory material. When the deformation of the portion made of the shape memory material is released,
A method for manufacturing an ink jet head, wherein the volume in the space is increased and recovered by the restoring force of the spring material.