JP2017228643A - Actuator, liquid discharge head, liquid discharge unit, and liquid discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that rigidity increases on the fixing end side fixed to the partition member of a thin film member and displacement efficiency decreases.SOLUTION: An actuator includes a deformable thin film member 12 having an opening 121, a partition member 11 forming a hollow section 111 placed on one side of the thin film member 12 and communicating with the opening 121, and a partition 112 around the hollow section 111, and a piezoelectric element 13, i.e., an electromechanical conversion element arranged around the opening 121 in the other surface of the thin film member 12, and deforming the thin film member 12. Piezoelectric film 132 of the piezoelectric element 13 faces across the hollow section 111 and partition 112 via the thin film member 12, and when the portion of thickness tmax of the piezoelectric film 132 is the maximum thickness portion 132a, film thickness of the portion 132b of the piezoelectric film 132 facing the hollow section 111 is thinner than the maximum thickness portion 132a of the piezoelectric film 132.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an actuator, a liquid discharge head, a liquid discharge unit, and an apparatus for discharging liquid.

  As a liquid discharge head, for example, a deformable nozzle plate having a nozzle for discharging liquid is provided with a piezoelectric element that bends and deforms, and the nozzle plate is deformed to pressurize the liquid in the liquid chamber and discharge the liquid from the nozzle There is.

  For example, a base material having a first surface, a second surface opposite to the first surface, and a cylindrical hole connecting the first surface and the second surface; A pressure chamber is formed by laminating one end of the hole by laminating with a surface, and a diaphragm having a nozzle communicating with the pressure chamber and a drive that deforms the diaphragm when a voltage is applied to change the volume of the pressure chamber An apparatus including a nozzle plate having an element is known (Patent Document 1).

JP-A-2015-186842

  By the way, an electromechanical conversion element is provided on one surface of the deformable thin film member, a hollow member for forming a hollow portion and a partition wall around the hollow portion is provided on the other surface side, and the hollow portion and the partition wall portion are opposed to each other through the thin film member. When the electromechanical conversion element is arranged across the region, there is a problem that the rigidity of the fixed end fixed to the partition member of the thin film member is increased and the displacement efficiency is lowered.

  The present invention has been made in view of the above problems, and an object thereof is to improve displacement efficiency.

In order to solve the above problems, an actuator according to the present invention is:
A deformable thin film member having an opening;
A partition member that is disposed on one surface side of the thin film member and that forms a hollow portion through which the opening communicates, and a partition portion around the hollow portion,
An electromechanical conversion element that is disposed around the opening on the other surface side of the thin film member, includes an electromechanical conversion film, and deforms the thin film member,
The electromechanical conversion film is provided in a region facing the hollow part and the partition part via the thin film member,
The maximum thickness portion of the electromechanical conversion film is located in a region facing the partition wall,
The thickness of the portion of the electromechanical conversion membrane facing the hollow portion is thinner than the thickness of the maximum thickness portion of the electromechanical conversion membrane.

  According to the present invention, the displacement efficiency can be improved.

It is a perspective explanatory view of the actuator concerning a 1st embodiment of the present invention. It is a cross-sectional explanatory drawing similarly. It is a section explanatory view of an actuator concerning a 2nd embodiment of the present invention. FIG. 10 is a cross-sectional explanatory view of a main part of a liquid ejection head according to a third embodiment of the present invention. It is principal part sectional drawing of the liquid discharge head which concerns on 4th Embodiment of this invention. FIG. 6 is an explanatory cross-sectional view before driving a piezoelectric element for explaining the operational effects of the liquid discharge head according to the present invention. It is a cross-sectional explanatory drawing when a piezoelectric element is similarly driven. FIG. 6 is an explanatory diagram for explaining the dimensions of each part of a liquid ejection head according to Comparative Examples 1 and 2 and Examples 1 and 2. It is explanatory drawing explaining the deformation amount of the nozzle plate of the comparative examples 1 and 2 and Example 1 as the exclusion volume of the liquid from a liquid chamber. It is explanatory drawing explaining the deformation amount of the nozzle plate of Example 2 as the exclusion volume of the liquid from a liquid chamber. It is principal part sectional drawing of the liquid discharge head which concerns on 5th Embodiment of this invention. It is a perspective explanatory view of an example of a device which discharges liquid concerning the present invention. It is principal part plane explanatory drawing of the other example of the apparatus which discharges the liquid which concerns on this invention. It is principal part side explanatory drawing of the apparatus. It is principal part plane explanatory drawing of the other example of the liquid discharge unit which concerns on this invention. It is front explanatory drawing of the further another example of the liquid discharge unit which concerns on this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to FIG. 1 and FIG. FIG. 1 is a perspective explanatory view of the actuator according to the embodiment, and FIG. 2 is a cross-sectional explanatory view.

  This actuator includes a deformable thin film member 12 having an opening 121, a partition member disposed on one surface side of the thin film member 12, and forming a hollow part 111 through which the opening 121 communicates and a partition part 112 around the hollow part 111. 11. The boundary between the hollow portion 111 and the partition wall portion 112 is defined as a boundary 113.

  And the electromechanical conversion which deform | transforms the deformable area | region 12a which is arrange | positioned around the opening 121 on the other surface side of the thin film member 12 and includes the piezoelectric film 132 which is an electromechanical conversion film and faces the hollow portion 111 of the thin film member 12 It has the piezoelectric element 13 which is an element. The electromechanical transducer is not limited to a piezoelectric element (the same applies to the following embodiments).

  Here, the piezoelectric film 132 of the piezoelectric element 13 is provided in a region facing the hollow portion 111 and the partition wall portion 112 through the thin film member 12.

  The maximum thickness portion 132 a of the piezoelectric film 132 is located in a region facing the partition wall portion 112. The film thickness (average film thickness) of the portion (region) 132b facing the hollow portion 111 of the piezoelectric film 132 is smaller than the thickness (maximum thickness tmax) of the maximum thickness portion 132a of the piezoelectric film 132.

  In the present embodiment, as shown in FIG. 1, the piezoelectric film 132 has an annular shape, and in the cross-sectional shape along the thickness direction of the thin film member 12, the piezoelectric film 132 is in the in-plane direction (referred to as the width direction) of the thin film member 12. The center position 135 is the maximum thickness position 134 of the maximum thickness tmax.

  The piezoelectric film 132 has a maximum thickness position 134 as a maximum thickness portion 132a, and has a portion where the thickness decreases while curving from the maximum thickness portion 132a to the opening 121 side and the opposite side to the opening 121 side. A part (region) 132 b facing the hollow portion 111 is partly formed. In the present embodiment, the maximum thickness portion 132a is only the maximum thickness position 134, but may have a shape having a thickness tmax portion in a predetermined range in the width direction.

  As described above, the piezoelectric film 132 having a symmetrical shape in the width direction with the central portion raised convexly is formed by, for example, applying a sol-gel liquid containing a PZT precursor by discharging it from a liquid discharge head, and applying the applied sol-gel. It can be easily formed by using a production method that repeats the steps of drying, pyrolysis and crystallization of the liquid.

  The piezoelectric element 13 is a thin film piezoelectric element in which a first electrode (lower electrode) 131, a piezoelectric film 132, and a second electrode (upper electrode) 133 are stacked from the thin film member 12 side. By applying a voltage between the electrode 133 and the electrode 133, it is bent and deformed.

  Thus, the piezoelectric film 132 of the piezoelectric element 13 is provided in a region facing the hollow portion 111 and the partition wall portion 112 via the thin film member 12, and the maximum thickness portion 132 a is formed in a region facing the partition wall portion 112. The film thickness (average film thickness) of the portion 132b that is located and faces the hollow portion 111 is thinner than the thickness tmax of the maximum thickness portion 132a.

  Thereby, even if the piezoelectric film 132 is disposed in a region facing the hollow portion 111 and the partition wall portion 112 through the thin film member 12, the rigidity of the fixed end side fixed to the partition wall member 11 of the thin film member 12 is high. Can be suppressed. Therefore, the displacement efficiency of the thin film member 12 can be improved.

  Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is an explanatory cross-sectional view of the actuator according to the embodiment.

  The piezoelectric film 132 has an annular shape as in the first embodiment, and the central position 135 in the width direction (in-plane direction of the thin film member 12) has a maximum thickness in the cross-sectional shape along the thickness direction of the thin film member 12. The shape is located closer to the boundary 113 than the position 134.

  That is, the piezoelectric film 132 has a cross-sectional shape along the thickness direction of the thin film member 12 and an asymmetric shape in the width direction. In the present embodiment, the maximum thickness portion 132a is only the maximum thickness position 134, but may have a shape having a thickness tmax portion in a predetermined range in the width direction.

  Thereby, the film thickness (average film thickness) of the part 132b facing the hollow part 111 of the piezoelectric film 132 can be made thinner than that of the first embodiment, and the fixed end side fixed to the partition wall member 11 of the thin film member 12 It can suppress that the rigidity of becomes higher than 1st Embodiment.

  In the first embodiment, in order to adjust the maximum thickness position 134 of the piezoelectric film 132, it is necessary to move the entire piezoelectric film 132 in the in-plane direction (here, the radial direction). On the other hand, in the second embodiment, there is no such necessity, and since the distance from the center of the opening 121 to the outer diameter of the piezoelectric film 132 does not change, the maximum thickness when the arrangement position of the piezoelectric film 132 cannot be changed. The position 134 can be changed.

  Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is an explanatory cross-sectional view of a main part of the liquid discharge head according to the embodiment.

  This liquid discharge head includes an actuator similar to that in the first embodiment. That is, a nozzle plate 22 that is a deformable thin film member having a nozzle 221 that is an opening for discharging a liquid, and a liquid chamber that is disposed on one surface side of the nozzle plate 22 and holds the liquid 20 that is a hollow portion through which the nozzle 221 communicates. 211 and a flow path member 21, which is a partition member that forms a partition wall 212 around the liquid chamber 211.

  And the electromechanical conversion which deform | transforms the deformable area | region 22a which is arrange | positioned around the nozzle 221 on the other surface side of the nozzle plate 22 and includes the piezoelectric film 232 which is an electromechanical conversion film and faces the liquid chamber 211 of the nozzle plate 22. It has the piezoelectric element 23 which is an element.

  Here, the piezoelectric film 232 of the piezoelectric element 23 is provided in a region facing the liquid chamber 211 and the partition wall 212 via the nozzle plate 22.

  The maximum thickness portion 232 a of the piezoelectric film 232 is located in a region facing the partition wall portion 212. The film thickness (average film thickness) of the portion (region) 232 b facing the liquid chamber 211 of the piezoelectric film 232 is thinner than the thickness (maximum thickness tmax) of the maximum thickness portion 232 a of the piezoelectric film 232.

  In the present embodiment, the piezoelectric film 232 has an annular shape as in the first embodiment, and is in the in-plane direction (referred to as the width direction) of the nozzle plate 22 in the cross-sectional shape along the thickness direction of the nozzle plate 22. The central position 235 is the maximum thickness position 234 of the maximum thickness tmax.

  The piezoelectric film 232 has a maximum thickness position 234 as a maximum thickness portion 232a, and has a portion where the thickness decreases while curving from the maximum thickness portion 232a to the nozzle 221 side and the nozzle 221 side opposite to the opening, A part of the portion where the thickness is reduced is a portion (region) 232 b facing the liquid chamber 211. In the present embodiment, the maximum thickness portion 232a is only the maximum thickness position 234, but it may be a shape having a thickness tmax portion in a predetermined range in the width direction.

  The piezoelectric element 23 is a thin film piezoelectric element in which a first electrode (lower electrode) 231, a piezoelectric film 232, and a second electrode (upper electrode) 233 are stacked from the nozzle plate 22 side. When a voltage is applied between the electrode 233 and the electrode 233, it is bent and deformed.

  As described above, the piezoelectric film 232 of the piezoelectric element 23 is provided in a region facing the liquid chamber 211 and the partition wall 212 via the nozzle plate 22, and the maximum thickness portion 232 a is formed in a region facing the partition wall 212. The thickness (average film thickness) of the portion 232b that is positioned and faces the liquid chamber 211 is thinner than the thickness tmax of the maximum thickness portion 232a.

  As a result, even if the piezoelectric film 232 is disposed in a region facing the liquid chamber 211 and the partition wall 212 via the nozzle plate 22, the rigidity of the fixed end side fixed to the flow path member 21 of the nozzle plate 22 is increased. It can suppress becoming high. Therefore, the displacement efficiency of the nozzle plate 22 can be improved, and the discharge efficiency is improved.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is an explanatory cross-sectional view of a main part of the liquid ejection head according to the embodiment.

  This liquid discharge head includes an actuator similar to that of the second embodiment. That is, the piezoelectric film 232 has an annular shape as in the first embodiment, and the cross-sectional shape along the thickness direction of the nozzle plate 22 has a center position 235 in the width direction (in-plane direction of the nozzle plate 22). The shape is located closer to the boundary 213 between the liquid chamber 211 and the partition wall 212 than the maximum thickness position 234.

  The piezoelectric film 232 has a cross-sectional shape along the thickness direction of the nozzle plate 22 and an asymmetric shape in the width direction. In the present embodiment, the maximum thickness portion 232a is only the maximum thickness position 234, but it may be a shape having a thickness tmax portion in a predetermined range in the width direction.

  Thereby, the film thickness (average film thickness) of the part 232b facing the liquid chamber 211 of the piezoelectric film 232 can be made thinner than that in the third embodiment, and the fixed end fixed to the flow path member 21 of the nozzle plate 22 It can suppress that the rigidity of a side becomes high rather than 3rd Embodiment.

  In the third embodiment, in order to adjust the maximum thickness position 234 of the piezoelectric film 232, it is necessary to move the entire piezoelectric film 232 in the in-plane direction (here, the radial direction). On the other hand, in the fourth embodiment, there is no such necessity, and since the distance from the center of the nozzle 221 to the outer diameter of the piezoelectric film 232 does not change, the maximum thickness when the arrangement position of the piezoelectric film 232 cannot be changed. The position 234 can be changed.

  Next, the function and effect of the liquid discharge head according to the present invention will be described with reference to FIGS. FIG. 6 is a cross-sectional explanatory diagram before driving the piezoelectric element for explaining the same effect, and FIG. 7 is a cross-sectional explanatory diagram when the piezoelectric element is similarly driven. 6 and 7 show a half region of the nozzle plate, the overall shape is the same as in FIGS. Moreover, although only the piezoelectric film is illustrated, the first electrode and the second electrode are provided as described in the above embodiment.

<Comparative Example 1>
As shown in FIG. 6A, a piezoelectric film 232 having a rectangular cross section (uniform thickness) is provided.

  The piezoelectric film 232 is disposed across a region facing the liquid chamber 211 and the partition wall 212 via the nozzle plate 22.

<Example 1>
As shown in FIG. 6C, similarly to the third embodiment, in the cross-sectional shape along the thickness direction of the nozzle plate 22, the piezoelectric film 232 in which the central position 235 becomes the maximum thickness position 234 (maximum thickness portion 232a). It has.

  The piezoelectric film 232 is disposed at a position where the maximum thickness position 234 (maximum thickness portion 232 a) faces the partition wall portion 212. Therefore, as in the third embodiment, the thickness of the portion 232b facing the liquid chamber 211 is thinner than the maximum thickness.

<Example 2>
As shown in FIG. 6D, in the same manner as in the fourth embodiment, in the cross-sectional shape along the thickness direction of the nozzle plate 22, the maximum thickness position 234 (maximum thickness portion) with respect to the boundary 213 across the center position 235. 232a) includes a piezoelectric film 232 on the opposite side.

  The piezoelectric film 232 is disposed at a position where the maximum thickness position 234 (maximum thickness portion 232 a) faces the partition wall portion 212. Accordingly, as in the fourth embodiment, the thickness of the portion 232b facing the liquid chamber 211 is thinner than the maximum thickness.

  Here, the dimensions of each part of the liquid ejection heads according to Comparative Examples 1 and 2 and Examples 1 and 2 were set as shown in FIG.

  7A to 7D show the deformation state of the nozzle plate 22 when a driving voltage of 20 V is applied to the piezoelectric element 23 including the piezoelectric film 232 of Comparative Examples 1 and 2 and Examples 1 and 2. Respectively.

<Comparative Example 1>
As shown in FIG. 7A, since the film thickness of the piezoelectric film 232 is constant, its rigidity is also constant regardless of the position of the piezoelectric film 232 in the width direction. It can be seen that the rigidity becomes high and the deformation amount is small.

<Example 1>
Since the maximum thickness portion 232a is disposed at a position facing the partition wall portion 212, the thickness of the piezoelectric film 232 on the fixed end side of the nozzle plate 22 is reduced, and the deformation amount of the nozzle plate 22 is smaller than that of the first comparative example. growing.

<Example 2>
The piezoelectric film 232 has an asymmetric shape in which the maximum thickness portion 232a is disposed at a position facing the partition wall 212 and the maximum thickness position 234 is opposite to the boundary 213 with respect to the center position 235 in the width direction. The film thickness (average film thickness) of the portion 232b facing the chamber 211 can be made thinner than that of the first embodiment.

  Next, the deformation amount of the nozzle plate of Comparative Examples 1 and 2 and Examples 1 and 2 will be described as an excluded volume of liquid from the liquid chamber with reference to FIGS.

  The excluded volume means the volume of liquid that is excluded from the liquid chamber 211 when the nozzle plate 22 is deformed by driving the piezoelectric element 23 from a state where the piezoelectric element 23 is not driven. Here, when the diameter of the liquid chamber 211 having a circular planar shape is 120 μm and the center position (nozzle center) of the nozzle 221 is “0 μm”, the boundary 213 between the liquid chamber 211 and the partition wall portion 212 is the nozzle It is assumed that the position is 60 μm from the center.

  FIG. 9 shows the relationship between the distance from the nozzle center of the maximum thickness portion 232a of the piezoelectric film 232 in Comparative Example 1 and Example 1 and the excluded volume.

  In Comparative Example 1, the thickness of the piezoelectric film 232 is constant, so the maximum thickness portion 232a is at the boundary 213 (position 60 μm from the nozzle center) between the liquid chamber 211 and the partition wall 212. The excluded volume in Comparative Example 1 was 1.07 [pl].

  Regarding Example 1, the excluded volume was measured by changing the distance from the nozzle center of the maximum thickness portion 232a of the piezoelectric film 232 between 61 μm and 70 μm. In this case, the maximum excluded volume was 7.29 pl at a position where the distance from the nozzle center was 67 μm.

  From this result, it can be seen that the liquid ejection head of Example 1 has higher nozzle plate displacement efficiency and higher ejection efficiency than the liquid ejection head of Comparative Example 1.

  FIG. 10 shows the relationship between the distance from the nozzle center of the maximum thickness portion 232a of the piezoelectric film 232 in Example 2 and the excluded volume.

  In Example 2, the excluded volume was measured by changing the distance from the nozzle center of the maximum thickness portion 232a of the piezoelectric film 232 between 61 μm and 70 μm. In this case, the maximum excluded volume was 7.50 pl at a position of 70 μm from the nozzle center. Further, the distance from the nozzle center at which the maximum excluded volume is obtained in Example 1 is 67 μm, which is 7.21 [pl].

  From this, it can be seen that the liquid ejection head of Example 2 has higher nozzle plate displacement efficiency and higher ejection efficiency than the liquid ejection head of Comparative Example 1.

  When Example 1 and Example 2 are compared, Example 1 has a maximum excluded volume that is greater than Example 2 at a position where the distance from the nozzle center at which the maximum excluded volume is obtained in Example 1 is 67 μm. You can see that it increases.

  Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 11 is an explanatory cross-sectional view of a main part of the liquid discharge head according to the embodiment.

  In the present embodiment, a plurality of nozzles 221 are formed on the nozzle plate 22 at a predetermined interval, and a flow path member 21 is formed that forms a plurality of liquid chambers 211 and partition walls 212 that each nozzle 221 faces. And the piezoelectric element 23 which deform | transforms the deformable area | region 22a corresponding to each liquid chamber 211 of the nozzle plate 22 is arrange | positioned corresponding to each liquid chamber 211, and the multi-nozzle head is comprised.

  Next, an example of an apparatus for ejecting liquid according to the present invention will be described with reference to FIG. FIG. 12 is a perspective view of the apparatus.

  In this apparatus, a Y-axis driving unit 301 is installed on a gantry 300, a stage 303 on which an object 302 is mounted is set on the Y-axis driving unit 301, and the stage 303 is moved to a Y-axis by the Y-axis driving unit 301. Reciprocated in the direction.

  An X-axis drive unit 305 is attached to the X-axis support member 304, and a head base 307 mounted on the Z-axis drive unit 306 is attached to the X-axis support member 304, and the head base 307 has the X-axis direction and the Z-axis direction. Moved in the direction.

  The head base 307 is equipped with one or a plurality of liquid ejection heads 308 according to the present invention for ejecting a liquid, and the liquid is supplied from the liquid reservoir through the supply means 309.

  By providing the liquid discharge head according to the present invention, it is possible to discharge liquid with high discharge efficiency.

  Next, another example of an apparatus for ejecting liquid according to the present invention will be described with reference to FIGS. FIG. 13 is an explanatory plan view of the main part of the apparatus, and FIG. 14 is an explanatory side view of the main part of the apparatus.

  This apparatus is a serial type apparatus, and the carriage 403 reciprocates in the main scanning direction by the main scanning moving mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, and the like. The guide member 401 spans the left and right side plates 491A and 491B and holds the carriage 403 so as to be movable. The carriage 403 is reciprocated in the main scanning direction by the main scanning motor 405 via the timing belt 408 spanned between the driving pulley 406 and the driven pulley 407.

  A liquid discharge unit 440 in which the liquid discharge head 404 and the head tank 441 according to the present invention are integrated is mounted on the carriage 403. The liquid discharge head 404 of the liquid discharge unit 440 discharges, for example, yellow (Y), cyan (C), magenta (M), and black (K) liquids. The liquid ejection head 404 is mounted with a nozzle row composed of a plurality of nozzles arranged in the sub-scanning direction orthogonal to the main scanning direction, and the ejection direction facing downward.

  The liquid stored in the liquid cartridge 450 is supplied to the head tank 441 by the supply mechanism 494 for supplying the liquid stored outside the liquid discharge head 404 to the liquid discharge head 404.

  The supply mechanism 494 includes a cartridge holder 451 that is a filling unit for mounting the liquid cartridge 450, a tube 456, a liquid feeding unit 452 including a liquid feeding pump, and the like. The liquid cartridge 450 is detachably attached to the cartridge holder 451. Liquid is fed from the liquid cartridge 450 to the head tank 441 by the liquid feeding unit 452 via the tube 456.

  This apparatus includes a transport mechanism 495 for transporting the paper 410. The transport mechanism 495 includes a transport belt 412 serving as transport means, and a sub-scanning motor 416 for driving the transport belt 412.

  The conveyance belt 412 adsorbs the paper 410 and conveys it at a position facing the liquid ejection head 404. The transport belt 412 is an endless belt and is stretched between the transport roller 413 and the tension roller 414. The adsorption can be performed by electrostatic adsorption or air suction.

  The transport belt 412 rotates in the sub-scanning direction when the transport roller 413 is rotationally driven by the sub-scanning motor 416 via the timing belt 417 and the timing pulley 418.

  Further, on one side of the carriage 403 in the main scanning direction, a maintenance / recovery mechanism 420 that performs maintenance / recovery of the liquid ejection head 404 is disposed on the side of the transport belt 412.

  The maintenance / recovery mechanism 420 includes, for example, a cap member 421 for capping the nozzle surface (surface on which the nozzle is formed) of the liquid ejection head 404, a wiper member 422 for wiping the nozzle surface, and the like.

  The main scanning movement mechanism 493, the supply mechanism 494, the maintenance / recovery mechanism 420, and the transport mechanism 495 are attached to a housing including the side plates 491A and 491B and the back plate 491C.

  In this apparatus configured as described above, the paper 410 is fed and sucked onto the transport belt 412, and the paper 410 is transported in the sub-scanning direction by the circular movement of the transport belt 412.

Therefore, the liquid ejection head 404 is driven in accordance with the image signal while moving the carriage 403 in the main scanning direction, thereby ejecting liquid onto the stopped paper 410 to form an image.

  Thus, since this apparatus includes the liquid ejection head according to the present invention, a high-quality image can be stably formed.

  Next, another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 15 is an explanatory plan view of the main part of the unit.

  The liquid discharge unit includes a casing portion composed of side plates 491A and 491B and a back plate 491C, a main scanning moving mechanism 493, a carriage 403, and a liquid among the members constituting the liquid discharge device. The discharge head 404 is configured.

  Note that a liquid discharge unit in which at least one of the above-described maintenance and recovery mechanism 420 and the supply mechanism 494 is further attached to, for example, the side plate 491B of the liquid discharge unit may be configured.

  Next, still another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 16 is an explanatory front view of the unit.

  This liquid discharge unit includes a liquid discharge head 404 to which a flow path component 444 is attached, and a tube 456 connected to the flow path component 444.

  The flow path component 444 is disposed inside the cover 442. A head tank 441 may be included instead of the flow path component 444. In addition, a connector 443 that is electrically connected to the liquid ejection head 404 is provided above the flow path component 444.

  In the present application, the liquid to be ejected is not particularly limited as long as it has a viscosity and surface tension that can be ejected from the head, and the viscosity becomes 30 mPa · s or less at room temperature, normal pressure, or by heating and cooling. It is preferable. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, functional materials such as polymerizable compounds, resins, and surfactants, and biocompatible materials such as DNA, amino acids, proteins, and calcium. , Edible materials such as natural pigments, solutions, suspensions, emulsions, and the like. These include, for example, inkjet inks, surface treatment liquids, components of electronic devices and light emitting devices, and formation of electronic circuit resist patterns. It can be used in applications such as liquids for use, three-dimensional modeling material liquids, and the like.

  As energy generation sources for discharging liquid, piezoelectric actuators (laminated piezoelectric elements and thin film piezoelectric elements), thermal actuators using electrothermal transducers such as heating resistors, electrostatic actuators consisting of a diaphragm and counter electrode are used. To be included.

  The “liquid discharge unit” includes a combination of at least one of a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, and a main scanning movement mechanism with a liquid discharge head.

  Here, the term “integrated” refers to, for example, a liquid discharge head, a functional component, and a mechanism that are fixed to each other by fastening, adhesion, engagement, etc., and one that is held movably with respect to the other. Including. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

  For example, there is a liquid discharge unit in which a liquid discharge head and a head tank are integrated. Also, there are some in which the liquid discharge head and the head tank are integrated by being connected to each other by a tube or the like. Here, a unit including a filter may be added between the head tank and the liquid discharge head of these liquid discharge units.

  In addition, there is a liquid discharge unit in which a liquid discharge head and a carriage are integrated.

  In addition, there is a liquid discharge unit in which the liquid discharge head and the scanning movement mechanism are integrated by holding the liquid discharge head movably on a guide member that constitutes a part of the scanning movement mechanism. In some cases, a liquid discharge head, a carriage, and a main scanning movement mechanism are integrated.

  Also, there is a liquid discharge unit in which a cap member that is a part of the maintenance / recovery mechanism is fixed to a carriage to which the liquid discharge head is attached, and the liquid discharge head, the carriage, and the maintenance / recovery mechanism are integrated. .

  In addition, there is a liquid discharge unit in which a tube is connected to a liquid discharge head to which a head tank or a flow path component is attached, and the liquid discharge head and a supply mechanism are integrated. The liquid from the liquid storage source is supplied to the liquid discharge head via this tube.

  The main scanning movement mechanism includes a guide member alone. The supply mechanism includes a single tube and a single loading unit.

The “apparatus for ejecting liquid” includes an apparatus that includes a liquid ejection head or a liquid ejection unit and that ejects liquid by driving the liquid ejection head. The apparatus for ejecting a liquid includes not only an apparatus capable of ejecting a liquid to an object to which the liquid can adhere, but also an apparatus for ejecting the liquid into the air or liquid.

  This “apparatus for discharging liquid” may include means for feeding, transporting, and discharging a liquid to which liquid can adhere, as well as a pre-processing apparatus and a post-processing apparatus.

  For example, as a “liquid ejecting device”, an image forming device that forms an image on paper by ejecting ink, a powder is formed in layers to form a three-dimensional model (three-dimensional model) There is a three-dimensional modeling apparatus (three-dimensional modeling apparatus) that discharges a modeling liquid onto the powder layer.

  Further, the “apparatus for ejecting liquid” is not limited to an apparatus in which significant images such as characters and figures are visualized by the ejected liquid. For example, what forms a pattern etc. which does not have a meaning in itself, and what forms a three-dimensional image are also included.

  The above-mentioned “applicable liquid” means that the liquid can be attached at least temporarily and adheres and adheres, or adheres and penetrates. Specific examples include recording media such as paper, recording paper, recording paper, film, and cloth, electronic parts such as electronic substrates and piezoelectric elements, powder layers (powder layers), organ models, and test cells. Yes, unless specifically limited, includes everything that the liquid adheres to.

  The material of the above-mentioned “material to which liquid can adhere” is not limited as long as liquid such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics can be adhered even temporarily.

  In addition, the “device for ejecting liquid” includes a device in which the liquid ejection head and the device to which the liquid can adhere move relatively, but is not limited thereto. Specific examples include a serial type apparatus that moves the liquid discharge head, a line type apparatus that does not move the liquid discharge head, and the like.

  In addition, as the “device for ejecting liquid”, other than the above, a treatment liquid coating apparatus that ejects a treatment liquid onto a sheet in order to apply the treatment liquid to the surface of the sheet for the purpose of modifying the surface of the sheet, There is an injection granulation apparatus that granulates raw material fine particles by spraying a composition liquid in which raw materials are dispersed in a solution through a nozzle.

  Note that the terms “image formation”, “recording”, “printing”, “printing”, “printing”, “modeling” and the like in the terms of the present application are all synonymous.

DESCRIPTION OF SYMBOLS 11 Partition member 12 Nozzle plate 13 Piezoelectric element 21 Flow path member 22 Nozzle plate 23 Piezoelectric element 111 Hollow part 112 Partition part 121 Opening 132 Piezoelectric film 211 Liquid chamber 212 Partition part 221 Nozzle 232 Piezoelectric film 211 Liquid chamber 212 Partition part 221 Nozzle 307 Liquid discharge head 403 Carriage 404 Liquid discharge head 440 Liquid discharge unit

Claims (9)

A deformable thin film member having an opening;
A partition member that is disposed on one surface side of the thin film member and that forms a hollow portion through which the opening communicates, and a partition portion around the hollow portion,
An electromechanical conversion element that is disposed around the opening on the other surface side of the thin film member, includes an electromechanical conversion film, and deforms the thin film member,
The electromechanical conversion film is provided in a region facing the hollow part and the partition part via the thin film member,
The maximum thickness portion of the electromechanical conversion film is located in a region facing the partition wall,
The actuator is characterized in that a thickness of a portion of the electromechanical conversion membrane facing the hollow portion is thinner than a thickness of a maximum thickness portion of the electromechanical conversion membrane. The electromechanical conversion film has a shape in which the thickness is reduced while curving from the maximum thickness portion to the opening side and the side opposite to the opening side in a cross-sectional shape along the thickness direction of the thin film member. The actuator according to claim 1. The maximum thickness portion of the electromechanical conversion film is a cross-sectional shape in a direction along the thickness direction of the thin film member, and a boundary between the hollow portion and the partition portion with a central position in the in-plane direction of the thin film member as a boundary. The actuator according to claim 1, wherein the actuator is located on a side opposite to the boundary. A deformable nozzle plate having an opening for discharging liquid;
A liquid chamber disposed on the one surface side of the nozzle plate and leading to the opening; and a flow path member forming a partition wall around the liquid chamber;
An electromechanical conversion element that is disposed around the nozzle on the other surface side of the nozzle plate, includes an electromechanical conversion film, and deforms the nozzle;
The electromechanical conversion film is provided in a region facing the liquid chamber and the partition through the nozzle plate,
The maximum thickness portion of the electromechanical conversion film is located in a region facing the partition wall,
The liquid discharge head according to claim 1, wherein a thickness of a portion of the electromechanical conversion film facing the hollow portion is thinner than a thickness of a maximum thickness portion of the electromechanical conversion film. The electromechanical conversion film has a shape in which a thickness is reduced while curving from the maximum thickness portion to the opening side and the side opposite to the opening side in a cross-sectional shape along a thickness direction of the nozzle plate. The liquid discharge head according to claim 4. The maximum thickness portion of the electromechanical conversion film has a cross-sectional shape in a direction along the thickness direction of the nozzle plate, and a boundary between the liquid chamber and the partition portion with a central position in the in-plane direction of the nozzle plate as a boundary. The liquid discharge head according to claim 4, wherein the liquid discharge head is located on a side opposite to the boundary.   A liquid discharge unit comprising the liquid discharge head according to claim 4. A head tank for storing liquid to be supplied to the liquid discharge head, a carriage on which the liquid discharge head is mounted, a supply mechanism for supplying liquid to the liquid discharge head, a maintenance / recovery mechanism for maintaining and recovering the liquid discharge head, and the liquid The liquid discharge unit according to claim 7, wherein at least one of a main scanning movement mechanism that moves the discharge head in a main scanning direction and the liquid discharge head are integrated.   An apparatus for ejecting liquid, comprising the liquid ejection head according to claim 4 or the liquid ejection unit according to claim 7 or 8.

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