JPH0515981Y2 - - Google Patents

Description

【考案の詳細な説明】 （産業上の利用分野） 本考案は、圧電素子の超音波振動を利用して液
体を吸い上げ霧化する超音波霧化装置に係り、と
くに霧化粒子の均一化を図つた超音波霧化装置の
構造の改良に関する。[Detailed description of the invention] (Field of industrial application) The present invention relates to an ultrasonic atomizer that uses ultrasonic vibrations of a piezoelectric element to suck up and atomize liquid. The present invention relates to an improvement in the structure of an ultrasonic atomization device.

（考案の概要） 本考案は、液体吸い上げ用穴を持つ軸体に圧電
素子を締め付け一体化したポンプ機能を持つ超音
波霧化装置において、前記軸体上側に形成された
霧化用ホーン部の上端に位置する板状部に多数の
微小貫通穴を形成した穴明き板を遊着して霧化粒
子の均一化を図つたものである。(Summary of the invention) The present invention is an ultrasonic atomizer having a pump function in which a piezoelectric element is tightened and integrated with a shaft body having a liquid suction hole, and the atomization horn portion formed on the upper side of the shaft body. A perforated plate with a large number of minute through-holes is attached to the plate-shaped part located at the upper end to make the atomized particles uniform.

（従来の技術） 本出願人は、特願昭61−309113号でボルト締め
振動子の構造を利用して液体の汲み上げ、霧化を
行う超音波ポンプを提案している。この特願昭61
−309113号に示した如き超音波ポンプの構造を第
４図に示す。(Prior Art) The present applicant has proposed an ultrasonic pump that pumps up and atomizes liquid by utilizing the structure of a bolted vibrator in Japanese Patent Application No. 309113/1982. This special request 1986
The structure of an ultrasonic pump as shown in No.-309113 is shown in FIG.

この第４図において、軸体１は下部にポンプ機
能のための振幅拡大ホーン部４（ステツプ状に直
径を小さく変化させることを省略して中間部と同
径とする場合もある）及び円板状部５を有すると
ともに、上部に霧化機能のための振幅拡大ホーン
部３０及び円板状部３１を備えている。軸体１の
中間部はボルト状であつて雄螺子部２，３が形成
されている。また、軸体１の中心軸上に液体吸い
上げ用貫通穴６が形成され、この液体吸い上げ用
貫通穴６の下方の開口は軸体１の下端面（すなわ
ち円板状部５の下端面）の中央に位置し、上方の
開口は軸体１の上端面（すなわち円板状部３１）
の中央に位置している。 In Fig. 4, the shaft body 1 has an amplitude-enlarging horn part 4 for the pump function (in some cases, the stepwise change in diameter is omitted and the diameter is the same as the middle part) and a disk. It has a shaped part 5, and is also provided with an amplitude expanding horn part 30 and a disc-shaped part 31 for the atomization function on the upper part. The intermediate portion of the shaft body 1 is bolt-shaped and has male screw portions 2 and 3 formed therein. Further, a liquid suction through hole 6 is formed on the central axis of the shaft body 1, and the lower opening of this liquid suction through hole 6 is formed on the lower end surface of the shaft body 1 (i.e., the lower end surface of the disc-shaped portion 5). Located in the center, the upper opening is the upper end surface of the shaft body 1 (i.e., the disc-shaped part 31)
It is located in the center of

そして、支持部分となる円板状フランジ８、円
板状電極板９Ａ、円板状圧電素子１０Ａ、円板状
電極板９Ｂ、円板状圧電素子１０Ｂ、円板状電極
板９Ｃ、円板状平ワツシヤ１２及び皿ばね１３の
各貫通穴に前記軸体１を挿通し、軸体１の雄螺子
部２，３にナツト１１Ａ，１１Ｂをそれぞれ螺合
し、締め付けることによつて、圧電素子１０Ａ，
１０Ｂ等の各部材は軸体１に締め付け一体化され
る。すなわち、圧電素子１０Ａ，１０Ｂと軸体１
との関係はボルト締め振動子とほぼ同様な構造と
なつている。 Then, a disc-shaped flange 8 serving as a supporting portion, a disc-shaped electrode plate 9A, a disc-shaped piezoelectric element 10A, a disc-shaped electrode plate 9B, a disc-shaped piezoelectric element 10B, a disc-shaped electrode plate 9C, a disc-shaped The piezoelectric element 10A is formed by inserting the shaft 1 into each through hole of the flat washer 12 and the disc spring 13, screwing the nuts 11A and 11B into the male threads 2 and 3 of the shaft 1, and tightening them. ，
Each member such as 10B is tightened and integrated with the shaft body 1. That is, the piezoelectric elements 10A, 10B and the shaft body 1
The relationship between the two is almost the same as that of a bolted vibrator.

この液体吸い上げと霧化を行う超音波ポンプ
は、液面Ｐが矢印Ｑの範囲内にあり、超音波ポン
プの下部が水等の液体に浸つている場合、電極板
９Ｂと電極板９Ａ，９Ｃとの間に高周波電圧を印
加すれば、圧電素子１０Ａ，１０Ｂは超音波振動
（例えば厚み振動）を発生し、その振動は軸体１
の下部の振幅拡大ホーン部４で拡大され、下端の
円板状部５に拡大された超音波の縦振動（第４図
の矢印Ｒのような軸に平行な方向の振動）を引き
起こす。この軸体下端の円板状部５の縦振動は、
矢印Ｓのように液体吸い上げ用貫通穴６を吹き上
げる向きの対流を引き起こし、これとともに、水
等の液体は空気に比べ超音波が伝搬しやすく粘性
が高い性質があり、液体吸い上げ用貫通穴６内の
液体を超音波振動が上昇する方向に進行していく
こと、及び貫通穴６内面が収縮する呼吸作用等に
起因して、液体は貫通穴６を上昇して行く。ま
た、圧電素子１０Ａ，１０Ｂの超音波振動は前記
振幅拡大ホーン部３０で振幅拡大されて円板状部
３１に拡大された縦振動を行わせる。この結果、
液体吸い上げ用貫通穴６を上昇した液体は、その
上部開口の位置する円板状部３１の上端面の超音
波振動にて霧化され、霧化粒子（噴霧粒子）とな
つて大気中に飛散する。 In the ultrasonic pump that sucks up and atomizes liquid, when the liquid level P is within the range of the arrow Q and the lower part of the ultrasonic pump is immersed in liquid such as water, the electrode plate 9B and the electrode plates 9A, 9C When a high frequency voltage is applied between
The vibration is magnified by the amplitude amplifying horn part 4 at the lower part of the ultrasonic wave, and causes vertical vibration (vibration in the direction parallel to the axis as indicated by arrow R in FIG. 4) of the ultrasonic wave, which is magnified by the disk-shaped part 5 at the lower end. The longitudinal vibration of the disc-shaped portion 5 at the lower end of the shaft body is
This causes convection in the direction of blowing up the liquid suction through hole 6 as shown by arrow S, and at the same time, since liquids such as water have a property in which ultrasonic waves propagate more easily than air and have a high viscosity, the inside of the liquid suction through hole 6 The liquid moves upward through the through hole 6 due to the progress of the liquid in the upward direction of the ultrasonic vibration and the breathing action of the inner surface of the through hole 6 contracting. Further, the amplitude of the ultrasonic vibrations of the piezoelectric elements 10A and 10B is expanded by the amplitude expansion horn section 30, causing the disk-shaped section 31 to perform an expanded longitudinal vibration. As a result,
The liquid that has risen through the liquid suction through hole 6 is atomized by ultrasonic vibration of the upper end surface of the disc-shaped part 31 where the upper opening is located, and becomes atomized particles (spray particles) and is dispersed into the atmosphere. do.

（考案が解決しようとする問題点） ところで、第４図の基本構造の超音波ポンプ
を、空気調和機や冷蔵庫のドレイン排水を霧化し
て蒸発させてしまう用途や液体燃料の霧化等に利
用することが本出願人より考慮されているが、こ
のような場合には霧化粒子が蒸発、気化し易いよ
うに、なるべく霧化粒子の粒径が小さいことが望
ましく、また粒径のばらつきも少なくすることが
要望される。しかし、第４図の基本構造では、以
下に列挙するような問題点があつた。(Problems to be solved by the invention) By the way, the ultrasonic pump with the basic structure shown in Figure 4 can be used to atomize and evaporate drain water from air conditioners and refrigerators, and to atomize liquid fuel. However, in such a case, it is desirable that the particle size of the atomized particles be as small as possible so that the atomized particles can easily evaporate and vaporize, and also to reduce the variation in particle size. It is desired to reduce the amount. However, the basic structure shown in FIG. 4 has the following problems.

(1) 霧化粒子は駆動周波数に依存しており、細か
い霧化粒子と霧化効率とは両立しない。(1) Atomized particles depend on the driving frequency, and fine atomized particles and atomization efficiency are not compatible.

(2) 霧化効率の良い駆動周波数では、霧化粒子
（噴霧粒子）の粒径は40〜70μmであり、ばらつ
きが大きい。(2) At a driving frequency that provides good atomization efficiency, the particle size of atomized particles (spray particles) is 40 to 70 μm, with large variations.

(3) 液体吸い上げ用貫通穴６が直接開口している
ため、大径の液体粒子が飛散、滴下したり、２
次粒子（２次凝集）現象が避けられない。(3) Since the through hole 6 for liquid suction is directly opened, large diameter liquid particles may scatter, drip, or
Secondary particle (secondary agglomeration) phenomenon is inevitable.

(4) 圧電素子への入力電力を増大させたり、送水
量を多くすると水滴状のものが飛散する。(4) If the input power to the piezoelectric element is increased or the amount of water is increased, water droplets will scatter.

（問題点を解決するための手段） 本考案は、上記の点に鑑み、液体吸い上げ用穴
の上部開口が位置する霧化用ホーン部先端側板状
部に、多数の微小貫通穴を形成した穴明き板をあ
る程度動き得るように遊びを持たせて取付ること
によつて、比較的微細な霧化粒子を得るととも
に、大径の液体粒子の飛散を防止して霧化粒子の
均一化を図つた超音波霧化装置を提供しようとす
るものである。(Means for Solving the Problems) In view of the above points, the present invention provides a hole in which a large number of minute through-holes are formed in the plate-shaped part on the tip side of the atomizing horn part where the upper opening of the liquid suction hole is located. By attaching the clear plate with some play so that it can move, relatively fine atomized particles can be obtained, and large-diameter liquid particles can be prevented from scattering to make the atomized particles uniform. The present invention is intended to provide an ultrasonic atomization device that achieves the desired results.

本考案は、上部に霧化用ホーン部及びその上端
に位置する板状部を形成し、該板状部の上端面に
開口する液体吸い上げ用穴を軸方向に形成した軸
体に、複数枚の圧電素子を締め付け手段で締め付
け一体化するとともに、前記板状部の外側を覆う
如く、多数の微小貫通穴を形成した穴明き板を被
せ、当該穴明き板と前記板状部の上端面との間に
液体の介在する微小間〓を生じるように該穴明き
板の折り曲げ部を前記板状部の下側基部に所要の
遊びを持たせて係合させた構成により、上記従来
の問題点を解消している。 The present invention includes an atomizing horn part and a plate-like part located at the upper end of the atomizing horn part, and a plurality of sheets are attached to a shaft body in which liquid suction holes are formed in the axial direction on the upper end surface of the plate-like part. A piezoelectric element is tightened and integrated with a tightening means, and a perforated plate having a large number of minute through holes is placed so as to cover the outside of the plate-like part, and the perforated plate and the above-mentioned plate-like part are The structure in which the bent part of the perforated plate is engaged with the lower base of the plate-like part with a required play so as to create a small gap between the end face and the end face allows liquid to be present between the folded part and the end face. This solves the problem.

（作用） 本考案の超音波霧化装置では、超音波による液
体霧化のためのホーン部先端側板状部に、多数の
微小貫通穴を形成した穴明き板を遊びを持たせて
装着するようにしており、軸体の液体吸い上げ用
穴から板状部上端面に溢れ出た水等の液体は、板
状部の上端面と前記穴明き板との間に発生した微
小間〓に浸入して板状部上端面全域に広がり、前
記穴明き板の多数の微小貫通穴に入る。各微小貫
通穴に達した液体は当該微小貫通穴の内径に一致
した微小液柱となり、これが前記板状部の超音波
振動により上方に放出され、霧化粒子となつて飛
散する。この場合、霧化粒子の径は、前記微小貫
通穴の内径で実質的に規制されるので、大粒の粒
子の飛散を防止して霧化粒子の均一化を図ること
ができる。また、霧化の指向性も良好となり、前
記板状部の上端面の上方に霧化粒子が高く放出さ
れる結果となる。さらに、前記板状部上端面と前
記穴明き板との微小間〓に液体が浸透して板状部
上端面全域に液体が広がり、板状部上端面全域で
霧化作用が行なわれるため、霧化効率が向上し、
霧化量を増大させ得る。(Function) In the ultrasonic atomization device of the present invention, a perforated plate with a large number of minute through-holes is attached with some play to the plate-like part on the tip side of the horn part for atomizing liquid by ultrasonic waves. In this way, liquid such as water overflowing from the liquid suction hole in the shaft body to the upper end surface of the plate-like part is absorbed into the minute gap created between the upper end surface of the plate-like part and the perforated plate. It penetrates and spreads over the entire upper end surface of the plate-like part, and enters the numerous minute through-holes of the perforated plate. The liquid that has reached each minute through-hole becomes a minute liquid column that matches the inner diameter of the minute through-hole, and is ejected upward by the ultrasonic vibration of the plate-like portion, becoming atomized particles and scattering. In this case, since the diameter of the atomized particles is substantially regulated by the inner diameter of the minute through-hole, scattering of large particles can be prevented and the atomized particles can be made uniform. Moreover, the directivity of atomization is also improved, resulting in a high amount of atomized particles being emitted above the upper end surface of the plate-shaped portion. Furthermore, the liquid permeates into the tiny gap between the upper end surface of the plate-like part and the perforated plate, and the liquid spreads over the entire upper end surface of the plate-like part, so that an atomization effect is performed over the entire upper end surface of the plate-like part. , atomization efficiency is improved,
The amount of atomization can be increased.

（実施例） 以下、本考案に係る超音波霧化装置の実施例を
図面に従つて説明する。(Example) Hereinafter, an example of the ultrasonic atomization device according to the present invention will be described with reference to the drawings.

第１図は本考案の第１実施例の要部構成を拡大
して示す。軸体１の上部で構成された液体霧化用
の振幅拡大ホーン部３０より下側の構造は前述の
第４図で説明した基本的な超音波ポンプと同様で
ある。 FIG. 1 shows an enlarged view of the main structure of a first embodiment of the present invention. The structure below the amplitude-enlarging horn section 30 for liquid atomization, which is formed at the upper part of the shaft body 1, is the same as the basic ultrasonic pump described in FIG. 4 above.

第１図において、液体霧化用のホーン部３０の
上端部は円板状部３１となつており、該円板状部
３１に微小貫通穴を多数形成した穴明き板３５
が、前記円板状部３１の上端面３７に対して液体
の介在する微小間〓を生じるごとく遊着されてい
る。すなわち、穴明き板３５の端部の折り曲げ部
３６は、円板状部３１の下側基部３８に対して、
ある程度の遊びを持たせて穴明き板３５が脱落し
ないように係合している。 In FIG. 1, the upper end of a horn section 30 for liquid atomization is a disc-shaped part 31, and the disc-shaped part 31 has a perforated plate 35 in which a large number of minute through-holes are formed.
is loosely attached to the upper end surface 37 of the disk-shaped portion 31 so as to create a minute gap in which liquid is present. In other words, the bent portion 36 at the end of the perforated plate 35 is formed with respect to the lower base portion 38 of the disc-shaped portion 31.
The perforated plate 35 is engaged with a certain amount of play to prevent it from falling off.

前記円板状部３１の上端面３７は平坦面であ
り、この中央部に軸体１を軸方向に貫通した液体
吸い上げ用貫通穴６が開口している。また、穴明
き板３５の円板状部上端面３７に対向する部分も
平らになつている。 The upper end surface 37 of the disc-shaped portion 31 is a flat surface, and a liquid suction through hole 6 that penetrates the shaft body 1 in the axial direction is opened at the center thereof. Further, the portion of the perforated plate 35 facing the upper end surface 37 of the disc-shaped portion is also flat.

第２図は円板状部３１の上端面３７及び穴明き
板３５の部分をさらに拡大したものである。この
図から判るように、穴明き板３５に形成された微
小貫通穴４０の穴径Ｒは穴明き板３５の厚みＴ以
下に設定され、しかも微小貫通穴４０の開口面積
よりも穴の無い残りの部分の面積のほうが大きく
なるように設定している。本考案者の実験によれ
ば、微小貫通穴４０の径Ｒを30μmとしたとき、
厚みＴを例えば60μm又は80μmとしたときに良い
結果が得られることを確認している。 FIG. 2 shows a further enlarged view of the upper end surface 37 of the disc-shaped portion 31 and the perforated plate 35. As shown in FIG. As can be seen from this figure, the hole diameter R of the minute through hole 40 formed in the perforated plate 35 is set to be less than or equal to the thickness T of the perforated plate 35, and moreover, the diameter R of the minute through hole 40 is set to be smaller than the thickness T of the perforated plate 35. The area is set so that the area of the remaining part without the area is larger. According to the inventor's experiments, when the diameter R of the minute through hole 40 is 30 μm,
It has been confirmed that good results can be obtained when the thickness T is set to 60 μm or 80 μm, for example.

第３図Ａ，Ｂは穴明き板３５に形成する微小貫
通穴４０の形状をそれぞれ示すもので、第３図Ａ
のように丸穴形状であつても、同図Ｂの角穴形状
であつもよい。いずれの場合も、開口率は50％以
下で、とくに５％乃至20％程度であることが好ま
しいと考えられる。 3A and 3B show the shapes of minute through holes 40 formed in the perforated plate 35, respectively.
It may be a round hole shape as shown in FIG. 2 or a square hole shape as shown in FIG. In either case, it is considered preferable that the aperture ratio is 50% or less, particularly about 5% to 20%.

上記構成において、液体吸い上げ用貫通穴６よ
り円板状部３１の上端面３７に達した水等の液体
Ｌは、穴明き板３５の取り付けに遊びがあるた
め、円板状部３１の超音波振動等により発生した
上端面３７と穴明き板３５との微小間〓Ｇに浸入
し、上端面３７の全域に行き渡り、各微小貫通穴
４０の内側に微小液柱４１を形成する。そして、
霧化用ホーン３０の先端の円板状部３１の超音波
振動により、微小液柱４１は霧化粒子となつて空
気中に放出される。この際、霧化粒子の径は微小
貫通穴４０の内径Ｒにより規制され、内径Ｒが例
えば30μmであれば、霧化粒子の径も30μm程度と
なることが判明した。 In the above configuration, the liquid L such as water that reaches the upper end surface 37 of the disc-shaped part 31 through the liquid suction through-hole 6 is caused The liquid penetrates into the micro gap G between the upper end surface 37 and the perforated plate 35 generated by sonic vibration, spreads over the entire upper end surface 37, and forms a micro liquid column 41 inside each micro through hole 40. and,
Due to the ultrasonic vibration of the disc-shaped portion 31 at the tip of the atomization horn 30, the minute liquid column 41 becomes atomized particles and is emitted into the air. At this time, it has been found that the diameter of the atomized particles is regulated by the inner diameter R of the minute through-hole 40, and if the inner diameter R is, for example, 30 μm, the diameter of the atomized particles will also be about 30 μm.

空気中で霧化粒子が効果的に気化するために
は、霧化粒子径は30μm以下であることが好まし
く、このため、前記微小貫通穴４０の内径Ｒは
30μm以下に設定されることが望まれる。さらに、
微小貫通穴４０内で充分な高さの微小液柱４１が
形成されるために穴明き板３５の厚みＴは、
30μm以上とすることが好ましい。 In order for the atomized particles to effectively vaporize in the air, the atomized particle diameter is preferably 30 μm or less. Therefore, the inner diameter R of the micro through hole 40 is
It is desirable that the thickness be set to 30 μm or less. moreover,
In order to form a micro liquid column 41 of sufficient height within the micro through hole 40, the thickness T of the perforated plate 35 is as follows.
The thickness is preferably 30 μm or more.

（考案の効果） 以上説明したように、本考案の超音波霧化装置
によれば、上部に霧化用ホーン部及びその上端に
位置する板状部を形成し、該板状部の上端面に開
口する液体吸い上げ用穴を軸方向に形成した軸体
に、複数枚の圧電素子を締め付け手段で締め付け
一体化するとともに、前記板状部に多数の微小貫
通穴を形成した穴明き板を、前記板状部の上端面
に対して液体の介在する微小間〓を生じるごとく
遊着した構成としたので以下の効果を得ることが
できる。(Effects of the invention) As explained above, according to the ultrasonic atomization device of the invention, an atomization horn part and a plate-shaped part located at the upper end of the horn part are formed in the upper part, and the upper end surface of the plate-shaped part A plurality of piezoelectric elements are tightened and integrated with a tightening means on a shaft body in which liquid suction holes opening in the axial direction are formed, and a perforated plate is provided in which a large number of minute through holes are formed in the plate-like part. Since the liquid is loosely attached to the upper end surface of the plate-shaped portion so as to create a small gap in which liquid is present, the following effects can be obtained.

(1) 水等の液体の霧化粒子（噴霧粒子）が微細で
均質である。(1) Atomized particles (spray particles) of liquid such as water are fine and homogeneous.

(2) 霧化の指向性を改善し、霧化粒子を板状部の
上方に勢い良く放出することができる。(2) The directionality of atomization can be improved, and atomized particles can be vigorously ejected above the plate-shaped part.

(3) 板状部の上端面と穴明き板との間に生ずる微
小間〓に液体が浸入し、均一な液体の膜が上端
面全域に存在することになり、霧化効率の向
上、ひいては霧化量の増大を図ることができ
る。(3) Liquid penetrates into the tiny gap created between the upper end surface of the plate-shaped part and the perforated plate, and a uniform film of liquid exists over the entire upper end surface, improving atomization efficiency. As a result, the amount of atomization can be increased.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本考案に係る超音波霧化装置の実施例
の要部構成を示す拡大断面図、第２図は実施例の
作用を説明するための拡大断面図、第３図Ａ，Ｂ
は穴明き板に設けた微小貫通穴の形状をそれぞれ
示す平面図、第４図は本出願人が先に提案してい
る超音波ポンプの基本構成を示す正断面図であ
る。 １……軸体、２，３……雄螺子部、４，３０…
…振幅拡大ホーン部、５，３１……円板状部、６
……液体吸い上げ用貫通穴、１０Ａ，１０Ｂ……
圧電素子、１１Ａ，１１Ｂ……ナツト、３５……
穴明き板、３６……折り曲げ部、３７……上端
面、４０……微小貫通穴、４１……微小液柱。 FIG. 1 is an enlarged cross-sectional view showing the main structure of an embodiment of the ultrasonic atomization device according to the present invention, FIG. 2 is an enlarged cross-sectional view for explaining the operation of the embodiment, and FIGS. 3A and B
4 is a plan view showing the shapes of minute through holes provided in a perforated plate, and FIG. 4 is a front sectional view showing the basic configuration of an ultrasonic pump previously proposed by the applicant. 1... Shaft body, 2, 3... Male screw part, 4, 30...
...Amplitude expansion horn part, 5, 31...Disc-shaped part, 6
...Through holes for liquid suction, 10A, 10B...
Piezoelectric element, 11A, 11B... Nut, 35...
Perforated plate, 36...Bending portion, 37...Upper end surface, 40...Minute through hole, 41...Minute liquid column.

Claims (1)

【実用新案登録請求の範囲】 (1) 上部に霧化用ホーン部及びその下端に位置す
る板状部を形成し、該板状部の上端面に開口す
る液体吸い上げ用穴を軸方向に形成した軸体
に、複数枚の圧電素子を締め付け手段で締め付
け一体化するとともに、前記板状部の外側を覆
う如く、多数の微小貫通穴を形成した穴明き板
を被せ、当該穴明き板と前記板状部の上端面と
の間に液体の介在する微小間〓を生じるように
該穴明き板の折り曲げ部を前記板状部の下側基
部に所要の遊びを持たせて係合させたことを特
徴とする超音波霧化装置。 (2) 前記微小貫通穴の直径が前記穴明き板の厚み
に等しいか、それ以下である実用新案登録請求
の範囲第１項記載の超音波霧化装置。[Claims for Utility Model Registration] (1) An atomizing horn part and a plate-shaped part located at the lower end thereof are formed in the upper part, and liquid suction holes opening in the upper end surface of the plate-shaped part are formed in the axial direction. A plurality of piezoelectric elements are tightened and integrated with the shaft body using a tightening means, and a perforated plate having a large number of minute through holes is placed so as to cover the outside of the plate-like part, and the perforated plate is The bent portion of the perforated plate is engaged with the lower base of the plate-like part with a required play so as to create a small gap in which liquid is present between the upper end surface of the plate-like part and the plate-like part. An ultrasonic atomization device characterized by: (2) The ultrasonic atomizer according to claim 1, wherein the diameter of the minute through-hole is equal to or less than the thickness of the perforated plate.