JP2021020203A - Liquid agent coating apparatus - Google Patents

Abstract

To provide a liquid agent coating apparatus which can smoothly discharge a liquid agent from a nozzle.SOLUTION: A liquid agent coating apparatus 100 includes a pressure chamber plate 8, a diaphragm 7 and a driving part 2 for pressurization. The pressure chamber plate 8 has a pressure chamber 82 for storing a liquid agent, an inflow passage 81 continuous to the pressure chamber 82, and a nozzle 83 continuous to the pressure chamber 82. The diaphragm 7 is arranged on the pressure chamber plate 8, and faces the nozzle 83. The driving part 2 for pressurization applies pressurization driving to the diaphragm 7. The pressure chamber plate 8 has a contact surface 8S in contact with the diaphragm 7. The pressure chamber 82 has a first pressure chamber 821 that is positioned in a range in which a distance from the contact surface 8S in a direction vertical to the contact surface 8S is larger than the inflow passage 81, and a second pressure chamber 822 that is continuous to the nozzle 83 and the first pressure chamber 821 and has an inside surface 822S having smaller inclination to the contact surface 8S than an inside surface 821S of the first pressure chamber 821, in a cross section vertical to the contact surface 8S.SELECTED DRAWING: Figure 10

Description

The present invention relates to a liquid agent coating device.

Piezoelectric elements that convert energy from electrical energy to mechanical energy by the piezoelectric effect have excellent responsiveness. Therefore, in a wide range of fields such as semiconductors, printing, and chemicals, a liquid agent coating device that discharges a liquid agent onto the surface of an object. It is used for.

Patent Document 1 discloses a liquid agent coating device including a head module having a pressure chamber for storing the liquid agent, an inflow path connected to the pressure chamber, and a nozzle connected to the pressure chamber.

Japanese Unexamined Patent Publication No. 2016-187892

In a liquid agent coating device, smooth liquid agent discharge from a nozzle is desired. An object of the present invention is to provide a liquid agent coating device capable of smoothly discharging a liquid agent from a nozzle.

The liquid agent coating device according to one aspect of the present invention includes a pressure chamber plate, a diaphragm, and a pressurizing drive unit. The pressure chamber plate has a pressure chamber for storing the liquid agent, an inflow path connected to the pressure chamber, and a nozzle connected to the pressure chamber. The diaphragm is arranged on the pressure chamber plate and faces the nozzle. The pressurizing drive unit applies pressurizing vibration to the diaphragm. The pressure chamber plate has a contact surface that contacts the diaphragm. The pressure chamber is connected to the nozzle and the first pressure chamber, and the first pressure chamber located in a range where the distance from the contact surface in the height direction perpendicular to the contact surface is larger than the inflow path in the cross section perpendicular to the contact surface. It has a second pressure chamber having an inner surface that is less inclined with respect to the contact surface than the inner surface of the first pressure chamber.

According to one aspect of the present invention, it is possible to provide a liquid agent coating device capable of smoothly ejecting a liquid agent from a nozzle.

FIG. 1 is a perspective view of a liquid agent coating device. FIG. 2 is an exploded perspective view of the liquid agent coating device. FIG. 3 is a cross-sectional view of the liquid agent coating device. FIG. 4 is a plan view of the diaphragm. FIG. 5 is a plan view of the pressure chamber plate. FIG. 6 is a perspective view of the pressure chamber plate. FIG. 7 is a cross-sectional view of the diaphragm, pressure chamber plate and seal. FIG. 8 is a cross-sectional view of the liquid agent coating device. FIG. 9 is a perspective view of the intermediate member. FIG. 10 is a cross-sectional view of the liquid agent coating device, showing a more preferable embodiment of the pressure chamber and the nozzle. FIG. 11 is a diagram showing another embodiment of the drive assembly.

Hereinafter, the liquid agent coating device according to the embodiment of the present invention will be described with reference to the drawings. However, the scope of the present invention is not limited to the following embodiments, and can be arbitrarily changed within the scope of the technical idea of the present invention. Further, in the following drawings, the scale and the number of each structure may be different from the scale and the number of the actual structure in order to make each configuration easy to understand.

As used herein, "connection" and "contact" are different concepts. By "connection" is meant that the two members are fixed or connected to each other. "Contact" means that the two members are in direct contact with each other, but the two members are not fixed or connected to each other.

As used herein, the term "parallel" is a concept that includes not only the case of being physically parallel but also the case of being substantially parallel. Substantially parallel means a case of tilting in a range of 15 ° or less. In addition, "vertical" is a concept that includes not only the case of being physically vertical but also the case of being substantially vertical. Substantially vertical means a case of tilting in a range of 15 ° or less.

(Liquid coating device 100)
The configuration of the liquid agent coating device 100 according to the present embodiment will be described with reference to the drawings. FIG. 1 is a perspective view of the liquid agent coating device 100. FIG. 2 is an exploded perspective view of the liquid agent coating device 100. FIG. 3 is a cross-sectional view of the liquid agent coating device 100. In FIG. 2, only the outline is shown so that the inside of the upper plate 6 can be seen.

The liquid agent coating device 100 includes a drive assembly 200 and a flow path assembly 300. The drive assembly 200 is a unit that generates a pressing force for discharging the liquid agent. The flow path assembly 300 is a unit for supplying a liquid agent.

(Drive Assembly 200)
The drive assembly 200 has a base plate 1 and a pressurizing drive unit 2. The pressurizing drive unit 2 includes a piezoelectric element 3, an intermediate member 4, and a weight member 5.

[Base plate 1]
The base plate 1 is placed on the flow path assembly 300. The base plate 1 is a member for fixing the position of the piezoelectric element 3 with respect to the flow path assembly 300. The base plate 1 has a first pillar portion 11, a second pillar portion 12, a beam portion 13, and a housing recess 14.

Each of the first and second pillar portions 11 and 12 is formed in a columnar shape. The beam portion 13 connects the upper end portions of the first and second column portions 11 and 12, respectively. Each of the first and second pillar portions 11 and 12 is connected to the upper plate 6 described later. As a result, the base plate 1 is positioned with respect to the flow path assembly 300.

The accommodating recess 14 is a gap surrounded by the first pillar portion 11, the second pillar portion 12, and the beam portion 13. The piezoelectric element 3 is accommodated in the accommodating recess 14.

The shape of the base plate 1 is not particularly limited as long as the position of the piezoelectric element 3 can be fixed with respect to the flow path assembly 300.

[Piezoelectric element 3]
The piezoelectric element 3 is accommodated in the accommodating recess 14. The piezoelectric element 3 is arranged between the beam portion 13 and the intermediate member 4. One end of the piezoelectric element 3 is connected to the beam portion 13, and the other end of the piezoelectric element 3 is connected to the intermediate member 4. The piezoelectric element 3 can be connected to each of the beam portion 13 and the intermediate member 4 by using an adhesive such as an epoxy resin.

The piezoelectric element 3 is displaced (expanded / contracted) in the z-axis direction in response to a drive pulse applied from a control unit (not shown). The displacement of the piezoelectric element 3 is transmitted to the diaphragm 7, which will be described later, via the intermediate member 4 and the weight member 5. The piezoelectric element 3 includes at least one piezoelectric body and a pair of electrodes. The piezoelectric element 3 may have a so-called partial electrode structure. As the piezoelectric element 3, various well-known piezoelectric elements can be used. The piezoelectric element 3 according to the present actual embodiment is formed in a prismatic shape, but may have another shape.

[Intermediate member 4]
The intermediate member 4 is accommodated in the accommodating recess 14. The intermediate member 4 is arranged between the piezoelectric element 3 and the weight member 5. The intermediate member 4 is a member for suppressing the concentration of stress on a part of the piezoelectric element 3 when the piezoelectric element 3 is displaced.

The intermediate member 4 is connected to the piezoelectric element 3. The intermediate member 4 can be connected to the piezoelectric element 3 by using an adhesive such as an epoxy resin. The intermediate member 4 comes into surface contact with the piezoelectric element 3. The intermediate member 4 makes point contact with the weight member 5. The intermediate member 4 can be separated from and contacted with the weight member 5. The detailed configuration of the intermediate member 4 will be described later.

[Weight member 5]
The weight member 5 is arranged between the intermediate member 4 and the diaphragm 7. The weight member 5 is arranged in the through hole 6c of the upper plate 6. The weight member 5 comes into contact with the intermediate member 4. The weight member 5 can be separated from and detached from the intermediate member 4. The weight member 5 is connected to the diaphragm 7. The weight member 5 can be connected to the diaphragm 7 by using an adhesive such as an epoxy resin or by welding.

The displacement of the piezoelectric element 3 is transmitted to the weight member 5 via the intermediate member 4. When the displacement of the piezoelectric element 3 is transmitted to the weight member 5, the weight member 5 functions as a weight and applies an inertial force to the diaphragm 7. As a result, the diaphragm 7 can be displaced relatively large compared to the minute displacement of the piezoelectric element 3.

The weight member 5 has a contact surface 51c that comes into contact with the diaphragm 7. The contact surface 51c is connected to the diaphragm 7. In the present embodiment, the outer edge shape of the contact surface 51c is circular.

The weight member 5 according to the present embodiment is formed in a columnar shape extending in the z-axis direction, but the weight member 5 may function as a weight, and its shape and size are not limited.

(Other Embodiments of Drive Assembly 200)
Hereinafter, other embodiments of the drive assembly 200 will be described with reference to FIG.

The drive assembly 200 deforms the diaphragm 35 in the thickness direction. Specifically, the drive assembly 200 includes a piezoelectric element 41, a first pedestal 42, a second pedestal 43, a plunger 44, a coil spring 45, and a casing 46.

The piezoelectric element 41 extends in one direction by applying a predetermined voltage. That is, the piezoelectric element 41 can be expanded and contracted in the one direction. The piezoelectric element 41 expands and contracts in the one direction to deform the diaphragm 35 in the thickness direction. The driving force for deforming the diaphragm 35 in the thickness direction may be generated by another driving element such as a magnetostrictive element.

The piezoelectric element 41 of the present embodiment has a rectangular parallelepiped shape that is long in one direction. Further, although not particularly shown, the piezoelectric element 41 of the present embodiment is electrically in a state in which a plurality of piezoelectric bodies 41a made of piezoelectric ceramics such as lead zirconate titanate (PZT) are laminated in one direction. It is configured by connecting to. That is, the piezoelectric element 41 has a plurality of piezoelectric bodies 41a laminated in one direction. As a result, the amount of expansion and contraction of the piezoelectric element 41 in one direction can be increased as compared with the case where the piezoelectric element 41 has one piezoelectric body. The shape of the piezoelectric element is not limited to a rectangular parallelepiped shape, and other shapes such as a columnar shape may be used.

The plurality of piezoelectric bodies 41a are electrically connected by side electrodes (not shown) located opposite to each other in the direction intersecting the one direction. Therefore, the piezoelectric element 41 extends in the one direction by applying a predetermined voltage to the side electrode. The predetermined voltage applied to the piezoelectric element 41 is a drive signal input from a control unit (not shown).

Since the configuration of the piezoelectric element 41 is the same as the configuration of the conventional piezoelectric element, detailed description thereof will be omitted. The piezoelectric element 41 may have only one piezoelectric body.

The plunger 44 is a rod-shaped member. One end in the axial direction of the plunger 44 comes into contact with the diaphragm 35. The other end of the plunger 44 in the axial direction comes into contact with the first pedestal 42, which will be described later, which covers the end of the piezoelectric element 41 in one direction. That is, the one direction of the piezoelectric element 41 coincides with the axial direction of the plunger 44. Further, the plunger 44 is located between the piezoelectric element 41 and the diaphragm 35. As a result, the expansion and contraction of the piezoelectric element 41 is transmitted to the diaphragm 35 via the plunger 44. The plunger 44 is a rod-shaped transmission member.

The other end of the plunger 44 is hemispherical. That is, the plunger 44 has a hemispherical tip on the piezoelectric element 41 side. As a result, the expansion and contraction of the piezoelectric element 41 can be reliably transmitted by the diaphragm 35 via the plunger 44.

The first pedestal 42 covers the end of the piezoelectric element 41 on the diaphragm 35 side in one direction. The first pedestal 42 comes into contact with the plunger 44. The second pedestal 43 covers the end of the piezoelectric element 41 on the opposite side of the diaphragm 35 in one direction. The second pedestal 43 is supported by the fixed casing bottom wall portion 47a of the fixed casing 47 described later.

The first pedestal 42 and the second pedestal 43 each have bottom portions 42a and 43a and vertical wall portions 42b and 43b located on the outer peripheral side, respectively. The bottom portions 42a and 43a each have a size that covers the end face of the piezoelectric element 41 in one direction. The vertical wall portions 42b and 43b each cover a part of the side surface of the piezoelectric element 41.

The first pedestal 42 and the second pedestal 43 are each made of a wear-resistant material. At least one of the first pedestal 42 and the second pedestal 43 may be made of a sintered material in order to improve wear resistance. Further, the hardness of the first pedestal 42 and the hardness of the second pedestal 43 may be different.

The piezoelectric element 41 is housed in the casing 46. The casing 46 has a fixed casing 47 and a pressurized casing 48. The pressurized casing 48 is housed in the fixed casing 47. The piezoelectric element 41 is housed in the pressurized casing 48. The fixed casing 47 and the pressurized casing 48 are fixed by bolts or the like (not shown). However, the fixed casing 47 and the pressurized casing 48 may have an integral structure.

The fixed casing 47 has a box shape with the diaphragm 35 side open. Specifically, the fixed casing 47 has a fixed casing bottom wall portion 47a and a fixed casing side wall portion 47b.

The fixed casing bottom wall portion 47a is located on the side opposite to the diaphragm 35 with the piezoelectric element 41 interposed therebetween. The fixed casing bottom wall portion 47a has a hemispherical protruding portion 47c that supports the one-way end portion of the piezoelectric element 41. That is, the liquid agent coating device 100 projects a hemispherical protruding portion 47c that projects from the bottom wall portion 47a of the fixed casing toward the piezoelectric element 41 in the one direction and supports the end portion of the piezoelectric element 41 opposite to the diaphragm 35. Have. Thereby, the end portion of the piezoelectric element 41 opposite to the diaphragm 35 can be supported by the protruding portion 47c of the fixed casing bottom wall portion 47a without one-sided contact. Therefore, the end portion of the piezoelectric element 41 opposite to the diaphragm 35 can be more reliably supported by the fixed casing bottom wall portion 47a.

The second pedestal 43 is located between the piezoelectric element 41 and the protruding portion 47c. That is, the liquid coating device 1 has a second pedestal 43 between the piezoelectric element 41 and the protruding portion 47c. As a result, while the end portion of the piezoelectric element 41 opposite to the diaphragm 35 is held by the second pedestal 43, the end portion of the piezoelectric element 41 opposite to the diaphragm 35 protrudes via the second pedestal 43. It can be supported more reliably by the portion 47c.

The pressurized casing 48 has a box shape in which the side opposite to the diaphragm 35 opens across the piezoelectric element 41. Therefore, in a state where the pressurized casing 48 is housed in the fixed casing 47, a part of the fixed casing bottom wall portion 47a is exposed in the casing 46. The above-mentioned protruding portion 47c is located at an exposed portion of the fixed casing bottom wall portion 47a.

The pressurized casing 48 has a pressurized casing bottom wall portion 48a and a pressurized casing side wall portion 48b.

The bottom wall portion 48a of the pressurized casing is located on the diaphragm 35 side. The bottom wall portion 48a of the pressurized casing has a through hole through which the plunger 44 penetrates. Therefore, the plunger 44 extends in one direction between the piezoelectric element 41 and the diaphragm 35, penetrates the bottom wall portion 48a of the pressurized casing, and transmits the expansion and contraction of the piezoelectric element 41 to the diaphragm 35.

The bottom wall portion 48a of the pressurized casing is supported by the upper surface of the base member 32. As a result, the force generated by the coil spring 45, which will be described later, sandwiched between the bottom wall portion 48a of the pressurized casing and the first pedestal 42 does not act on the diaphragm 35 supported by the base member 32, or acts on the diaphragm 35. Even very small.

Further, the pressurized casing bottom wall portion 48a holds a coil spring 45, which will be described later, between the first pedestal 42 and the coil spring 45.

The outer surface of the side wall portion 48b of the pressurized casing contacts the inner surface of the side wall portion 47b of the fixed casing, and the inner surface of the side wall portion 48b of the pressurized casing contacts the vertical wall portions 42b and 43b of the first pedestal 42 and the second pedestal 43. As a result, the first pedestal 42 and the second pedestal 43 can be held by the pressurized casing side wall portion 48b. Therefore, even when a predetermined voltage is applied to the piezoelectric element 41, deformation of the piezoelectric element 41 in a direction orthogonal to the one direction is suppressed.

With the above configuration, the piezoelectric element 41 is sandwiched in one direction by the plunger 44 and the protruding portion 47c of the fixed casing bottom wall portion 47a. As a result, when the piezoelectric element 41 expands and contracts in the one direction, the expansion and contraction of the piezoelectric element 41 can be transmitted to the diaphragm 35 by the plunger 44. Therefore, the diaphragm 35 can be deformed in the thickness direction by expanding and contracting the piezoelectric element 41. Note that FIG. 11 shows the movement of the plunger 44 due to the expansion and contraction of the piezoelectric element 41 in one direction by a solid arrow.

The coil spring 45 is a spring member that spirally extends along the axis in one direction. The coil spring 45 is sandwiched in one direction by the first pedestal 42 and the bottom wall portion 48a of the pressurized casing. A rod-shaped plunger 44 penetrates the coil spring 45 in the axial direction. That is, the first pedestal 42 is located between the piezoelectric element 41 and the plunger 44 and the coil spring 45. Further, the coil spring 45 extends along the axis of the plunger 44 between the piezoelectric element 41 and the bottom wall portion 48a of the pressurized casing.

As a result, the coil spring 45 applies a force to compress the piezoelectric element 41 in the one direction via the first pedestal 42. In FIG. 11, the compressive force of the coil spring 45 is indicated by a white arrow. The compressive force generated by the coil spring 45 is preferably a force that positions the first pedestal 42 at a position where it comes into contact with the plunger 44 in a state where no voltage is applied to the piezoelectric element 41. For example, the compressive force is preferably 30 to 50% of the force generated in the piezoelectric element 41 when the rated voltage is applied to the piezoelectric element 41.

Moreover, since the first pedestal 42 is located between the piezoelectric element 41 and the plunger 44 and the coil spring 45, the expansion and contraction of the piezoelectric element 41 can be stably transmitted to the plunger 44 via the first pedestal 42. At the same time, the compressive force of the coil spring 45 can be stably transmitted to the piezoelectric element 41 via the first pedestal 42.

Here, when the viscosity of the liquid is high, it is required to operate the piezoelectric element 41 at high speed. Therefore, it is conceivable to improve the responsiveness of the piezoelectric element 41 by inputting a rectangular wave drive signal to the piezoelectric element 41. In this case, when the piezoelectric element 41 expands and contracts at high speed, the piezoelectric element 41 may expand and contract excessively, causing damage such as peeling inside. In particular, when the piezoelectric element 41 has a plurality of piezoelectric bodies 41a stacked in the expansion / contraction direction, the high-speed operation of the piezoelectric element 41 tends to cause damage such as peeling inside the piezoelectric element 41. The excessive expansion and contraction of the piezoelectric element 41 means that the expansion and contraction amount of the piezoelectric element 41 is larger than the maximum expansion and contraction amount when the rated voltage is applied to the piezoelectric element 41.

On the other hand, by compressing the piezoelectric element 41 in the one direction by the coil spring 45 as in the present embodiment, even when a rectangular wave drive signal is input to the piezoelectric element 41, the expansion and contraction of the piezoelectric element 41 causes the piezoelectric element 41 to expand and contract. It is possible to prevent damage such as peeling from occurring inside the piezoelectric element 41. That is, the coil spring 45 can suppress excessive expansion and contraction of the piezoelectric element 41, and can prevent the occurrence of internal damage due to expansion and contraction of the piezoelectric element 41. As a result, the durability of the piezoelectric element 41 can be improved.

Moreover, since the coil spring 45 is located between the piezoelectric element 41 and the pressurized casing bottom wall portion 48a as described above, the elastic restoring force of the coil spring 45 can be received by the pressurized casing bottom wall portion 48a. .. Therefore, it is possible to prevent the diaphragm 35 from being deformed by the elastic restoring force of the coil spring 45.

Therefore, it is possible to prevent the liquid from leaking from the discharge port 32a and the liquid discharge performance from being deteriorated. Further, the plunger 44 and the coil spring 45 can be arranged compactly by penetrating the coil spring 45 spirally extending along the axis in the axial direction. As a result, the liquid agent coating device 100 can be downsized.

(Flow path assembly 300)
The flow path assembly 300 has an upper plate 6, a diaphragm 7, a pressure chamber plate 8, and a seal 9.

[Upper plate 6]
The upper plate 6 is arranged on the diaphragm 7. The upper plate 6 comes into contact with the diaphragm 7 on the diaphragm side surface 6S. The diaphragm side surface 6S according to this embodiment is a flat surface.

The upper plate 6 has a through hole 6c, a liquid supply passage 6d, a drainage passage 6e, and a diaphragm side surface 6S.

The liquid supply passage 6d guides the liquid agent supplied from the storage tank (not shown) via the barrel joint 61 to the inflow passage 81 of the pressure chamber plate 8 described later. A barrel joint 61 for connecting a liquid supply pipe (not shown) extending from the storage tank is attached to the inlet of the liquid supply passage 6d. The drainage passage 6e guides the liquid agent discharged from the outflow passage 84 of the pressure chamber plate 8 described later to the outside. A drainage joint 62 for connecting a drainage pipe (not shown) extending to the outside is attached to the outlet of the drainage passage 6e. Instead of the drainage joint 62, a stopper for removing air bubbles mixed in the pressure chamber 82 may be attached to the outlet of the drainage passage 6e.

[Diaphragm 7]
The diaphragm 7 is formed in a plate shape extending in the x-axis direction and the y-axis direction. The x-axis direction is a direction perpendicular to the y-axis direction and the z-axis direction. The y-axis direction is a direction perpendicular to the x-axis direction and the z-axis direction.

The diaphragm 7 is arranged on the pressure chamber plate 8. The diaphragm 7 is sandwiched between the upper plate 6 and the pressure chamber plate 8. The diaphragm 7 comes into contact with the upper plate 6 on the upper plate side surface 7S. The diaphragm 7 comes into contact with the pressure chamber plate 8 on the pressure chamber plate side surface 7T.

FIG. 4 is a plan view of the diaphragm 7 as viewed from the upper plate side surface 7S. The diaphragm 7 has a liquid supply hole 7e, a drainage hole 7f, and a flexible region 7g.

The liquid supply hole 7e is connected to the liquid supply passage 6d of the upper plate 6 and the inflow passage 81 of the pressure chamber plate 8 described later. The drainage hole 7f is connected to the drainage passage 6e of the upper plate 6 and the outflow passage 84 of the pressure chamber plate 8 described later.

The flexible region 7g is a part of the diaphragm 7. The flexible region 7g is a region of the diaphragm 7 that does not come into contact with the upper plate 6 and the pressure chamber plate 8. The pressurizing drive unit 2 is arranged on the flexible region 7g. The contact surface 51c of the weight member 5 is connected to the flexible region 7g. The outer edge shape of the flexible region 7g in a plan view is the same circular shape as the contact surface 51c of the weight member 5.

The flexible region 7g covers the pressure chamber 82 of the pressure chamber plate 8 described later. The displacement of the piezoelectric element 3 is transmitted to the flexible region 7g via the intermediate member 4 and the weight member 5, whereby the flexible region 7g elastically vibrates in the z-axis direction. As described above, of the diaphragm 7, only the flexible region 7 g functions as a vibrating membrane.

[Pressure chamber plate 8]
The pressure chamber plate 8 is formed in a plate shape extending in the x-axis direction and the y-axis direction. A diaphragm 7 is arranged on the pressure chamber plate 8. The pressure chamber plate 8 is arranged parallel to the diaphragm 7. The pressure chamber plate 8 comes into contact with the diaphragm 7 at the contact surface 8S. In this embodiment, the size of the pressure chamber plate 8 is equivalent to the size of the diaphragm 7.

FIG. 5 is a plan view of the pressure chamber plate 8 as viewed from the contact surface 8S. FIG. 6 is a perspective view of the pressure chamber plate 8 as viewed from the contact surface 8S. FIG. 7 is a cross-sectional view taken along the line AA of FIG. 5 in which the diaphragm 7, the pressure chamber plate 8, and the seal 9 are cut. FIG. 7 is a cross section perpendicular to the contact surface 8S.

The pressure chamber plate 8 has an inflow passage 81, a pressure chamber 82, a nozzle 83, an outflow passage 84, and a seal groove 85.

The inflow path 81 is composed of a first recess C1 formed on the contact surface 8S. The inflow path 81 is formed by closing the first recess C1 with the diaphragm 7. The inflow path 81 extends along the contact surface 8S. The inflow path 81 according to the present embodiment extends parallel to the x-axis direction. In this way, the inflow path 81 is formed by closing the recess formed on the surface of the pressure chamber plate 8 with the diaphragm 7 instead of forming the through hole inside the pressure chamber plate 8. Therefore, since the pressure chamber plate 8 can be made thinner, the volume change rate of the pressure chamber 82 corresponding to the vibration amount of the diaphragm 7 can be increased by reducing the volume of the pressure chamber 82. As a result, even if the pressing force of the diaphragm 7 is small, a large amount of pressure can be applied to the liquid agent in the pressure chamber 82, and the pressing force can be efficiently transmitted. Therefore, a liquid agent having a higher viscosity can be nozzleed with lower power consumption. It can be discharged from 83.

The inflow path 81 has a rectangular cross section as shown in FIG. The width W1 of the inflow path 81 in the y-axis direction (an example in the plane direction) parallel to the contact surface 8S is larger than the height H1 of the inflow path 81 in the z-axis direction (an example in the thickness direction) perpendicular to the contact surface 8S. That is, the ratio of the height H1 to the width W1 of the inflow path 81 is smaller than 1. By forming the inflow path 81 flat in this way, the pressure chamber plate 8 can be further thinned, so that the liquid agent coating device 100 can be further miniaturized.

One end of the inflow path 81 is connected to the liquid supply hole 7e of the diaphragm 7. The liquid agent is supplied to the inflow passage 81 via the liquid supply hole 7e of the diaphragm 7 and the liquid supply passage 6d of the upper plate 6. The other end of the inflow path 81 is connected to the pressure chamber 82. The liquid agent supplied to the inflow passage 81 flows into the pressure chamber 82. The detailed configuration of the inflow path 81 will be described later.

The pressure chamber 82 is composed of a second recess C2 formed in the contact surface 8S. The pressure chamber 82 is formed by closing the second recess C2 with the diaphragm 7. Therefore, since the pressure chamber plate 8 can be made thinner, the volume change rate of the pressure chamber 82 corresponding to the vibration amount of the diaphragm 7 can be increased by reducing the volume of the pressure chamber 82. The outer edge shape of the second recess C2 (that is, the pressure chamber 82) is circular like the contact surface 51c of the weight member 5 and the flexible region 7g of the diaphragm 7. The range of the flexible region 7g in the diaphragm 7 is defined by the outer edge of the second recess C2.

The pressure chamber 82 stores the liquid agent flowing in from the inflow passage 81. The liquid agent stored in the pressure chamber 82 is discharged from the nozzle 83. Further, the liquid agent stored in the pressure chamber 82 may be discharged from the outflow passage 84 in order to remove air bubbles mixed in the pressure chamber 82. The detailed configuration of the pressure chamber 82 will be described later.

The nozzle 83 is connected to the pressure chamber 82. The nozzle 83 is a hole that penetrates the pressure chamber plate 8. The nozzle 83 opens to the outer surface 8T of the pressure chamber plate 8. The nozzle 83 faces the diaphragm 7 in the z-axis direction. The nozzle 83 is arranged inside the pressure chamber 82 in the plan view of the contact surface 8S. The nozzle 83 is arranged at the center of the pressure chamber 82 in the plan view of the contact surface 8S. The outer edge shape of the nozzle 83 is circular like the pressure chamber 82. The liquid agent stored in the pressure chamber 82 is discharged to the outside from the nozzle 83. The detailed configuration of the nozzle 83 will be described later.

The outflow passage 84 is composed of a third recess C3 formed in the contact surface 8S. The outflow passage 84 is formed by closing the third recess C3 with the diaphragm 7. Therefore, since the pressure chamber plate 8 can be made thinner, the volume change rate of the pressure chamber 82 corresponding to the vibration amount of the diaphragm 7 can be increased by reducing the volume of the pressure chamber 82. The outflow path 84 extends along the contact surface 8S. The outflow path 84 according to the present embodiment extends parallel to the x-axis direction. One end of the outflow passage 84 is connected to the pressure chamber 82. The other end of the inflow path 81 is connected to the drain hole 7f of the diaphragm 7. When removing the air bubbles mixed in the pressure chamber 82, the liquid agent is discharged from the outflow passage 84 to the outside through the drainage hole 7f of the diaphragm 7 and the drainage passage 6e of the upper plate 6.

The seal groove 85 is formed on the contact surface 8S. The seal groove 85 is provided around the first to third recesses C1 to C3 in the plan view of the contact surface 8S. The seal groove 85 is provided along the outer edge of the first to third recesses C1 to C3. The seal groove 85 surrounds the entire first to third recesses C1 to C3. The seal groove 85 is formed in an annular shape.

[Seal 9]
The seal 9 is sandwiched between the diaphragm 7 and the pressure chamber plate 8 as shown in FIG. The seal 9 is arranged in the seal groove 85 of the pressure chamber plate 8. The seal 9 surrounds the inflow passage 81, the pressure chamber 82, and the outflow passage 84 of the pressure chamber plate 8. The seal 9 is pressed against the diaphragm 7 in a state of being arranged in the seal groove 85. As a result, the liquidtightness and airtightness of the inflow passage 81, the pressure chamber 82, and the outflow passage 84 are ensured. The seal 9 can be made of an elastic member such as rubber.

(Flow resistance of inflow path 81 and nozzle 83)
In the present embodiment, the ratio of the flow path resistance in the nozzle 83 to the flow path resistance in the inflow path 81 is 1 or more. That is, the flow path resistance in the nozzle 83 is the same as the flow path resistance in the inflow path 81, or larger than the flow path resistance in the inflow path 81. Therefore, when the liquid agent is continuously discharged from the nozzle 83, the liquid agent can be smoothly replenished from the inflow passage 81 to the pressure chamber 82.

The ratio of the flow path resistance of the nozzle 83 to the flow path resistance of the inflow path 81 is preferably 2 or less. That is, the flow path resistance in the nozzle 83 is preferably twice or less the flow path resistance in the inflow path 81. As a result, when pressure vibration is applied from the pressurizing drive unit 2 to the diaphragm 7 (specifically, the flexible region 7 g) and the volume of the pressure chamber 82 becomes smaller, the inflow path 81 from the pressure chamber 82 It is possible to prevent the liquid agent from flowing back. As a result, the liquid agent can be smoothly discharged from the nozzle 83 in response to the pressurized vibration of the diaphragm 7.

The flow path resistance in the inflow path 81 is calculated by cross-sectional analysis over the entire length of the inflow path 81. Similarly, the flow path resistance in the nozzle 83 is calculated by cross-sectional analysis over the entire length of the nozzle 83. In this cross-sectional analysis, the flow path resistance can be calculated from the following general formula (1) used for calculating the pressure loss.

p1-p2 = U × (8 × μ × L) / (π × r4) ・ ・ ・ (1)

In the formula (1), p1-p2 is the pressure loss, p1 is the pressure on the inflow side (unit: Pa), and p2 is the pressure on the outflow side (unit: Pa). Further, in the equation (1), μ is a viscosity coefficient (unit: N · sec / m2), L is a flow path length (unit: m), and r is a flow path radius (unit: m). U is the flow rate (unit: m3 / sec).

(Shape of pressure chamber 82 and nozzle 83)
FIG. 8 is a cross-sectional view of the liquid agent coating device 100 cut along the line BB of FIG. FIG. 8 is a cross section perpendicular to the contact surface 8S of the pressure chamber plate 8.

The pressure chamber 82 (second recess C2) is formed in an overall tapered shape toward the nozzle 83. The pressure chamber 82 has a tapered shape toward the nozzle 83. Therefore, the width W2 of the pressure chamber 82 in the x-axis direction (an example in the plane direction) parallel to the contact surface 8S becomes narrower as it approaches the nozzle 83 from the diaphragm 7.

As a result, the volume of the pressure chamber 82 can be reduced, so that the volume change rate of the pressure chamber 82 corresponding to the vibration amount of the diaphragm 7 (specifically, the flexible region 7 g) can be increased. As a result, even if the diaphragm 7 is small, a large amount of pressure can be applied to the liquid agent in the pressure chamber 82, and the pressing force can be efficiently transmitted. Therefore, a liquid agent having a higher viscosity can be discharged from the nozzle 83 with lower power consumption. Can be made to. In particular, in the present embodiment, the pressure chamber plate 8 is made thinner by forming the inflow passage 81 with the first recess C1, and the volume of the pressure chamber 82 can be easily reduced, so that the pressure chamber 82 can be added more efficiently. Pressure can be transferred to the liquid. Further, since the wall thickness of the pressure chamber plate 8 around the nozzle 83 can be increased as compared with the case where the pressure chamber 82 is formed in a columnar shape, even if the total length of the nozzle 83 is shortened to reduce the flow path resistance. The rigidity of the pressure chamber plate 8 can be ensured.

Further, the total width W2max of the pressure chamber 82 in the x-axis direction is larger than the total height H2max of the pressure chamber 82 in the z-axis direction (an example in the thickness direction). By forming the pressure chamber 82 flat in this way, the pressure chamber plate 8 can be made thinner, so that the liquid agent coating device 100 can be made smaller. The total height H2max of the pressure chamber 82 is the distance between the diaphragm 7 and the nozzle 83 in the z-axis direction.

The ratio of the total width W2max to the total height H2max of the pressure chamber 82 is preferably 10 or more. That is, the total width W2max of the pressure chamber 82 is preferably 10 times or more the total height H2max. As a result, the pressing force from the diaphragm 7 can be transmitted to the liquid agent more efficiently, and the liquid agent coating device 100 can be further miniaturized.

In the present embodiment, the cross section of the pressure chamber 82 has a truncated cone shape. Specifically, the pressure chamber 82 has a cross-sectional shape in which the apex portion of the cone having the flexible region 7g of the diaphragm 7 as the bottom surface is removed. Therefore, the inner side surface 82S of the pressure chamber 82 is a partial conical surface excluding the apex portion of the conical surface. However, the pressure chamber 82 may be formed in a tapered shape toward the nozzle 83, and its cross section is not limited to the truncated cone shape.

The nozzle 83 is formed so as to be generally tapered toward the outer surface 8T. The nozzle 83 has a tapered shape toward the outer surface 8T. Therefore, the width W3 of the nozzle 83 in the x-axis direction parallel to the contact surface 8S becomes narrower as the distance from the pressure chamber 82 increases.

In the present embodiment, the cross section of the nozzle 83 is a truncated cone shape. Specifically, the nozzle 83 has a cross-sectional shape in which the apex portion of the cone having the pressure chamber 82 as the bottom surface is removed. Therefore, the inner side surface 83S of the nozzle 83 is a partial conical surface excluding the apex portion of the conical surface. However, the nozzle 83 may be formed in a tapered shape toward the outer surface 8T, and its cross section is not limited to the truncated cone shape.

Here, the inner surface 83S of the nozzle 83 has a larger inclination with respect to the contact surface 8S than the inner surface 82S of the pressure chamber 82. That is, the inner surface 83S of the nozzle 83 is more inclined with respect to the xy plane than the inner surface 82S of the pressure chamber 82. Therefore, the wall thickness of the pressure chamber plate 8 around the nozzle 83 can be increased, so that the rigidity around the nozzle 83 can be ensured.

Further, as shown in FIG. 8, the central shaft 83A of the nozzle 83 coincides with the central shaft 82A of the pressure chamber 82. Therefore, since the pressing force can be efficiently transmitted from the pressure chamber 82 to the nozzle 83, the liquid agent can be discharged more smoothly from the nozzle 83.

Further, the central shaft 2A of the pressurizing drive unit 2 coincides with the central shaft 82A of the pressure chamber 82 and the central shaft 83A of the nozzle 83, respectively. Therefore, since the pressing force can be efficiently transmitted from the pressurizing drive unit 2 to the pressure chamber 82, the liquid agent can be discharged more smoothly from the nozzle 83.

(Structure of intermediate member 4)
FIG. 9 is a perspective view of the intermediate member 4.

The intermediate member 4 is connected to the tip of the piezoelectric element 3. The intermediate member 4 has a flat surface 4S connected to the piezoelectric element 3. The plane 4S is formed in a plane.

The intermediate member 4 has a curved surface 4T provided on the opposite side of the plane 4S. The curved surface 4T makes point contact with the weight member 5 (see FIG. 8). The curved surface 4T may be a part of a spherical surface or a curved surface. By making the curved surface 4T point-contact with the weight member 5, the durability of the piezoelectric element 3 can be improved.

Although the intermediate member 4 according to the present embodiment is formed in a hemispherical shape, it is sufficient if it has a flat surface 4S and a curved surface 4T, and its shape and size are not particularly limited.

The intermediate member 4 is preferably made of a material having a hardness higher than that of the weight member 5. Further, the intermediate member 4 is preferably made of a material having higher wear resistance than the weight member 5. Examples of such a material include martensitic stainless steel (for example, SUS440), ceramic material (for example, alumina), ruby and the like. As a result, the number of times the intermediate member 4 connected to the piezoelectric element 3 with a normal adhesive is worn or deformed and the intermediate member 4 is replaced together with the piezoelectric element 3 can be reduced, so that maintenance time and maintenance cost can be suppressed. it can.

(Features)
In the pressure chamber plate 8 according to the present embodiment, the width W2 of the pressure chamber 82 in the plane direction parallel to the contact surface 8S is narrower as it approaches the nozzle 83 from the diaphragm 7. Therefore, as compared with the case where the pressure chamber 82 is formed with a uniform diameter, the volume change rate of the pressure chamber 82 corresponding to the vibration amount of the diaphragm 7 is increased by reducing the volume of the pressure chamber 82, and the pressure chamber 82 is formed. The flow path resistance in 82 can be reduced. As a result, the pressing force from the diaphragm 7 can be efficiently transmitted to the liquid agent in the pressure chamber 82, so that the liquid agent can be smoothly discharged from the nozzle 83.

(More preferred embodiments of the pressure chamber 82 and the nozzle 83)
Hereinafter, more preferred embodiments of the pressure chamber 82 and the nozzle 83 will be described with reference to FIG. FIG. 10 is a cross-sectional view of the liquid agent coating device 100 cut along the line corresponding to the line BB in FIG. FIG. 10 is a cross section perpendicular to the contact surface 8S of the pressure chamber plate 8.

The liquid agent coating device 100 according to one aspect of the present invention includes a pressure chamber plate 8, a diaphragm 7, and a pressurizing drive unit 2. The pressure chamber plate 8 has a pressure chamber 82 for storing the liquid agent, an inflow passage 81 connected to the pressure chamber 82, and a nozzle 83 connected to the pressure chamber 82. The diaphragm 7 is arranged on the pressure chamber plate 8 and faces the nozzle 83. The pressurizing drive unit 2 applies pressurizing vibration to the diaphragm 7. The pressure chamber plate 8 has a contact surface 8S that contacts the diaphragm 7. The pressure chamber 82 includes a first pressure chamber 821 and a nozzle 83 located in a range where the distance from the contact surface 8S in the height direction perpendicular to the contact surface 8S is larger than that of the inflow path 81 in the cross section perpendicular to the contact surface 8S. And a second pressure chamber 822 which is connected to the first pressure chamber 821 and has an inner side surface 822S which is smaller in inclination with respect to the contact surface 8S than the inner side surface 821S of the first pressure chamber 821.

Here, the liquid agent coating device 100 protrudes from the pressure chamber plate 8 and includes a convex portion 86 having a first pressure chamber 821, a second pressure chamber 822, and a nozzle 83, and the convex portion 86 is a pressure chamber. It may be a part of the plate 8, or may be a separate body from the pressure chamber plate 8 and may be attached to the pressure chamber plate 8.

The nozzle 83 opens on the tip surface 87 of the convex portion 86. If the liquid agent collects around the outer opening 83a of the nozzle 83 on the tip surface 87, the liquid agent cannot be smoothly discharged from the nozzle 83. Therefore, it is desirable that the surface area of the tip surface 87 is smaller in order to prevent the liquid agent from accumulating around the outer opening 83a of the nozzle 83. The tip surface 87 may be a flat surface or a curved surface such as a spherical surface.

The effect of the turbulent flow generated on the liquid agent in the inflow passage 81 on the liquid agent stored in the second pressure chamber 822 and the nozzle 83 is suppressed by the liquid agent stored in the first pressure chamber 821. As a result, the pressing force can be efficiently transmitted from the pressurizing drive unit 2 to the second pressure chamber 822 and the nozzle 83, so that the liquid agent can be smoothly discharged from the nozzle 83.

Here, in the cross section perpendicular to the contact surface 8S, the total Hs of the height of the first pressure chamber 821, the height of the second pressure chamber 822, and the height of the nozzle 83 in the height direction perpendicular to the contact surface 8S is. It is preferably at least twice the total width of the first pressure chamber 821 in the plane direction parallel to the contact surface 8S.

As a result, the effect of the turbulent flow generated in the liquid agent in the inflow passage 81 on the liquid agent stored in the second pressure chamber 822 and the nozzle 83, particularly on the liquid agent stored in the vicinity of the opening of the nozzle 83, is the first. It is further suppressed by the liquid agent stored in the pressure chamber 821. As a result, the pressing force can be more efficiently transmitted from the pressurizing drive unit 2 to the second pressure chamber 822 and the nozzle 83, so that the liquid agent can be discharged more smoothly from the nozzle 83.

Further, the height of the nozzle 83 in the height direction perpendicular to the contact surface 8S is preferably low. As a result, the liquid agent can be discharged more smoothly from the nozzle 83.

In the cross section perpendicular to the contact surface 8S, the width of the pressure chamber 82 in the plane direction parallel to the contact surface 8S is preferably narrower as it approaches the nozzle 83 from the diaphragm 7.

Here, as a preferred embodiment, the first pressure chamber 821 has a columnar shape and the second pressure chamber 822 has a truncated cone shape in a cross section perpendicular to the contact surface 8S.

Compared with the case where the pressure chamber 82 is formed with a uniform diameter, the volume change rate of the pressure chamber 82 corresponding to the vibration amount of the diaphragm 7 is increased by reducing the volume of the pressure chamber 82, and the inside of the pressure chamber 82 is increased. Flow path resistance can be reduced. As a result, the pressing force from the diaphragm 7 can be efficiently transmitted to the liquid agent in the pressure chamber 82, so that the liquid agent can be smoothly discharged from the nozzle 83.

In the cross section perpendicular to the contact surface 8S, the width 83W of the outer opening 83a of the nozzle 83 in the plane direction parallel to the contact surface 8S is preferably the width 82W or less of the inner opening 82a of the pressure chamber 82 in the plane direction. The internal opening 82a of the pressure chamber 82 is connected to the nozzle 82. The internal opening 82a is a boundary between the pressure chamber 82 and the nozzle 83. The outer opening 83a of the nozzle 83 is an example of the “second opening” according to the present invention. The outer opening 83a of the nozzle 83 opens to the outer surface of the pressure chamber plate 8. The liquid agent is discharged from the outer opening 83a of the nozzle 83 toward the surface of the object. The outer opening 83a of the nozzle 83 is an example of the “second opening” according to the present invention.

By setting the width 83W of the outer opening 83a to the width 82W or less of the inner opening 82a in this way, the liquid agent can be discharged more smoothly.

Here, Table 1 below shows how the discharge performance of the liquid agent discharged from the outer opening 83a is changed when the ratio (83W / 82W) of the width 83W of the outer opening 83a to the width 82W of the inner opening 82a is changed. It shows the result of verifying whether it changes.

The criteria for evaluating the discharge performance shown in Table 1 are as follows. Evaluation A means that the nozzle 83 could be continuously discharged 1000 times or more without causing a liquid pool on the tip surface 87 of the nozzle 83. Evaluation B means that the nozzle 83 could be continuously discharged 500 times or more without causing a liquid pool on the tip surface 87 of the nozzle 83. Evaluation C means that although a liquid pool was generated on the tip surface 87 of the nozzle 83, the nozzle 83 could be continuously discharged 300 times or more. Evaluation D means that a liquid pool was formed on the tip surface 87 of the nozzle 83, and continuous ejection could not be performed 100 times or more. Evaluation E means that a liquid pool was formed on the tip surface 87 of the nozzle 83, and continuous ejection could not be performed 10 times or more.

As is clear from Table 1, the sample No. in which the width 83W of the outer opening 83a is set to the width 82W or less of the inner opening 82a. In Nos. 7 and 8, the sample No. 8 in which the width 83W of the outer opening 83a was made larger than the width 82W of the inner opening 82a. Compared with 1 to 6, the discharge performance of the liquid agent could be particularly improved. Such a result was obtained by reducing the volume of the nozzle 83 to increase the volume change rate of the nozzle 83 corresponding to the vibration amount of the diaphragm 7 and to reduce the flow path resistance in the nozzle 83. Because it was made. As a result, the pressing force from the diaphragm 7 could be efficiently transmitted to the liquid agent in the nozzle 83, so that the liquid agent could be smoothly discharged from the nozzle 83.

On the other hand, sample No. In 1 to 6, at the outer opening 83a of the nozzle 83, the liquid agent was attracted to the tip surface 87 by the Coanda effect and adhered around the outer opening 83a of the nozzle 83. As a result, the liquid agent was accumulated around the outer opening 83a of the nozzle 83, and the liquid agent could not be smoothly discharged from the nozzle 83.

Here, as a preferred embodiment, the nozzle 83 has a truncated cone shape in a cross section perpendicular to the contact surface 8S. By forming the nozzle 83 into a truncated cone shape, it is possible to further suppress the liquid agent from being attracted to the tip surface 87 by the Coanda effect at the outer opening 83a of the nozzle 83.

Further, in the cross section perpendicular to the contact surface 8S, the nozzle 83 has a truncated cone shape, the second pressure chamber 822 has a truncated cone shape, and the angle of the inner surface 83S of the nozzle 83 with respect to the contact surface 8S is with respect to the contact surface 8S. It is preferably equal to or greater than the angle of the inner surface 822S of the second pressure chamber 822.

As a result, the pressing force from the diaphragm 7 can be efficiently transmitted from the liquid agent in the second pressure chamber 822 to the liquid agent in the nozzle 83, so that the liquid agent can be discharged more smoothly from the nozzle 83. Further, since the wall thickness of the pressure chamber plate 8 around the nozzle 83 can be increased, the rigidity around the nozzle 83 can be ensured.

Alternatively, in the cross section perpendicular to the contact surface 8S, the nozzle 83 has a truncated cone shape, the second pressure chamber 822 has a truncated cone shape, and the angle of the inner surface 83S of the nozzle 83 with respect to the contact surface 8S is with respect to the contact surface 8S. It is preferably equal to the angle of the inner surface 822S of the second pressure chamber 822. In this case, the inner surface 83S of the nozzle 83 and the inner surface 82S of the second pressure chamber 822 are on the same surface. As described above, when the nozzle 83 and the second pressure chamber 822 are integrated to form one truncated cone shape in the cross section perpendicular to the contact surface 8S, there is no boundary between the nozzle 83 and the second pressure chamber 822. ..

As a result, the distance between the outer opening 83a of the nozzle 83 in the height direction and the inner opening 82a of the pressure chamber 82 is minimized, so that the height of the nozzle 83 in the height direction is minimized (substantially 0). Can be done. As a result, the liquid agent can be discharged more smoothly from the nozzle 83.

Further, as a preferred embodiment, the nozzle 83 has a columnar shape in a cross section perpendicular to the contact surface 8S.

Here, the fact that the nozzle 83 is columnar means that the diameter of the opening of the nozzle 83 is equal to or larger than the diameter of the surface of the nozzle 83 in contact with the second pressure chamber 822, and the diameter of the opening of the nozzle 83 is the diameter of the nozzle 83. This includes cases where the diameter of the surface in contact with the second pressure chamber 822 is less than 1.04 times.

As a result, the flow path resistance in the nozzle 83 can be reduced, and the pressing force from the diaphragm 7 can be efficiently transmitted from the liquid agent in the second pressure chamber 822 to the liquid agent in the nozzle 83. The liquid agent can be smoothly discharged from 83.

In the cross section perpendicular to the contact surface 8S, the first pressure chamber 821 is cylindrical, the second pressure chamber 822 is truncated cone-shaped, and the central axis of the nozzle 83, the central axis of the first pressure chamber 821, and the first (2) It is preferable that the central axis of the pressure chamber 822 coincides with the central axis.

As a result, the pressing force can be efficiently transmitted from the pressure chamber 82 to the nozzle 83, so that the liquid agent can be discharged more smoothly from the nozzle 83.

Further, in the cross section perpendicular to the contact surface 8S, it is preferable that the central axis of the pressurizing drive unit 2 coincides with the central axes of the nozzle 83, the first pressure chamber 821, and the second pressure chamber 822, respectively.

As a result, the pressing force can be efficiently transmitted from the pressurizing drive unit 2 to the pressure chamber 82, so that the liquid agent can be discharged more smoothly from the nozzle 83.

(Modified example of embodiment)
Although the present invention has been described in accordance with the above embodiments, the statements and drawings that form part of this disclosure should not be understood to limit the invention. Various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art from this disclosure.

[Modification 1]
In the pressure chamber plate 8 according to the above embodiment, the inflow passage 81, the pressure chamber 82, and the outflow passage 84 are formed on the contact surface 8S, but even if they are each formed inside the pressure chamber plate 8. Good. In this case, the liquid agent coating device 100 does not have to include the seal 9.

[Modification 2]
Although the pressure chamber plate 8 according to the above embodiment has an outflow passage 84, it does not have to have an outflow passage 84.

[Modification 3]
The width W3 of the nozzle 83 according to the above embodiment is narrower as the distance from the pressure chamber 82 increases, but the width W3 is not limited to this.

[Modification example 4]
The size of the diaphragm 7 according to the above embodiment is the same as the size of the pressure chamber plate 8, but the diaphragm 7 should be of a size capable of covering the inflow passage 81, the pressure chamber 82, and the outflow passage 84. Just do it.

[Modification 5]
In the above embodiment, the base plate 1 is positioned with respect to the flow path assembly 300 by connecting the first and second pillar portions 11 and 12 to the upper plate 6, but the positioning method of the base plate 1 is appropriately changed. It is possible.

[Modification 6]
In the above embodiment, the diaphragm 7, the pressure chamber plate 8, and the upper plate 6 are connected to each other, but they may be connected to each other by screws, for example.

[Modification 7]
In the above embodiment, the pressurizing drive unit 2 has the piezoelectric element 3, the intermediate member 4, and the weight member 5, but it suffices to have at least the piezoelectric element 3, and the intermediate member 4 and the weight member 5 need to be provided. It is not necessary to have at least one of.

[Modification 8]
Although not particularly mentioned in the above embodiment, the members (upper plate 6, diaphragm 7, and pressure chamber plate 8) of the flow path assembly 300 that come into contact with the liquid agent are preferably made of a material having corrosion resistance to the liquid agent. However, if the surface of these members that comes into contact with the liquid agent is covered with a corrosion-resistant film or the like, various constituent materials can be adopted.

[Modification 9]
In another embodiment of the drive assembly 200, in the above embodiment, the liquid agent coating device 100 changes the volume of the liquid chamber 33 by deformation of the diaphragm 35 in the thickness direction, thereby causing the liquid agent in the liquid chamber 33 to be externalized. It is a so-called inkjet type liquid agent coating device that discharges. However, the liquid agent coating device may be a so-called nozzle type liquid agent coating device that discharges the liquid agent from the nozzle according to the pressure change in the liquid chamber. Further, the configuration of the so-called inkjet type liquid agent coating device is not limited to the configuration of the present embodiment as long as the liquid agent in the liquid chamber 33 can be discharged to the outside by deformation in the thickness direction of the diaphragm.

[Modification 10]
In another embodiment of the drive assembly 200, in the embodiment, the coil spring 45 compresses the piezoelectric element 41 in one direction. However, if the piezoelectric element can be compressed in one direction, the piezoelectric element may be compressed by a configuration other than the coil spring. That is, in the above embodiment, the coil spring 45, which is a spiral spring member, is mentioned as an example of the compressive force applying portion, but the present invention is not limited to this, and the spiral spring member has a predetermined length and has a predetermined length. A so-called coiled wave spring in which a wire rod or a flat plate having a wavy shape is spirally wound may be used. Further, the compressive force applying portion may have a structure other than the spiral shape as long as the piezoelectric element can be compressed in one direction. It is preferable that the compressive force applying portion is arranged so as not to interfere with the plunger regardless of the configuration.

1 Base plate 2 Pressurization drive 3 Piezoelectric element 4 Intermediate member 4S Flat surface 4T Curved surface 5 Weight member 6 Upper plate 6d Liquid supply path 6e Drainage path 6S Diaphragm side surface 7 Diaphragm 7e Liquid supply hole 7f Drainage hole 7g Flexible area 7S Upper plate side surface 7T Pressure chamber Plate side surface 8 Pressure chamber plate C1 First recess C2 Second recess C3 Third recess 81 Inflow path 82 Pressure chamber 83 Nozzle 84 Outflow path 85 Seal groove 8S Contact surface 9 Seal 100 Liquid agent coating device 200 Drive assembly 300 Flow path assembly 821 First pressure chamber 822 Second pressure chamber 86 Convex portion 87 Tip surface 32 Base member 32a Discharge port 33 Liquid chamber 35 Diaphragm 41 Piezoelectric element 41a Piezoelectric body 42 First pedestal 42a Bottom 42b Vertical wall portion 43 2nd pedestal 43a Bottom 43b Vertical wall 44 Plunger 45 Coil spring 46 Casing 47 Fixed casing 47a Fixed casing Bottom wall 47b Fixed casing Side wall 47c Protruding 48 Pressurized casing 48a Pressurized casing Bottom wall 48b Pressurized casing Side wall

Claims (12)

A pressure chamber plate having a pressure chamber for storing a liquid agent, an inflow path connected to the pressure chamber, and a nozzle connected to the pressure chamber.
A diaphragm arranged on the pressure chamber plate and facing the nozzle,
A pressurizing drive unit that applies pressurizing vibration to the diaphragm,
With
The pressure chamber plate has a contact surface in contact with the diaphragm and has a contact surface.
The pressure chamber
In the cross section perpendicular to the contact surface, the first pressure chamber located in a range where the distance from the contact surface in the height direction perpendicular to the contact surface is larger than the inflow path, and
It has a second pressure chamber that is connected to the nozzle and the first pressure chamber and has an inner surface that is less inclined with respect to the contact surface than the inner surface of the first pressure chamber.
Liquid agent application device. In the cross section, the sum of the height of the first pressure chamber, the height of the second pressure chamber, and the height of the nozzle in the height direction is the sum of the height of the first pressure chamber in the plane direction parallel to the contact surface. More than twice the full width of
The liquid agent coating device according to claim 1. In the cross section, the width of the pressure chamber in the plane direction is narrower as it approaches the nozzle from the diaphragm.
The liquid agent coating device according to claim 2. In the cross section, the first pressure chamber is cylindrical.
The liquid agent coating device according to claim 3. In the cross section, the second pressure chamber has a truncated cone shape.
The liquid agent coating device according to claim 3 or 4. In the cross section, the pressure chamber has a first opening connected to the nozzle.
In the cross section, the nozzle has a second opening that opens to the outer surface of the pressure chamber plate.
In the cross section, the width of the second opening in the plane direction parallel to the contact surface is equal to or less than the width of the first opening in the plane direction.
The liquid agent coating device according to any one of claims 1 to 5. In the cross section, the nozzle has a truncated cone shape.
The liquid agent coating device according to claim 6. In the cross section, the second pressure chamber has a truncated cone shape, and the angle of the inner surface of the nozzle with respect to the contact surface is equal to or greater than the angle of the inner surface of the second pressure chamber with respect to the contact surface.
The liquid agent coating device according to claim 7. In the cross section, the second pressure chamber has a truncated cone shape, and the angle of the inner surface of the nozzle with respect to the contact surface is the same as the angle of the inner surface of the second pressure chamber with respect to the contact surface.
The liquid agent coating device according to claim 7. In the cross section, the nozzle is cylindrical.
The liquid agent coating device according to claim 6. In the cross section, the first pressure chamber is cylindrical, the second pressure chamber is truncated cone-shaped, the central axis of the nozzle, the central axis of the first pressure chamber, and the second pressure chamber. Aligns with the central axis,
The liquid agent coating device according to any one of claims 7 to 10. In the cross section, the central axis of the pressurizing drive unit coincides with the central axes of the nozzle, the first pressure chamber, and the second pressure chamber.
The liquid agent coating device according to claim 11.

Images