JPS6338647B2 - - Google Patents
Info
- Publication number
- JPS6338647B2 JPS6338647B2 JP58228581A JP22858183A JPS6338647B2 JP S6338647 B2 JPS6338647 B2 JP S6338647B2 JP 58228581 A JP58228581 A JP 58228581A JP 22858183 A JP22858183 A JP 22858183A JP S6338647 B2 JPS6338647 B2 JP S6338647B2
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- clean
- fluid resistance
- exhaust duct
- measuring device
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
- G01F1/34—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by measuring pressure or differential pressure
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Volume Flow (AREA)
- Devices For Use In Laboratory Experiments (AREA)
- Testing Or Measuring Of Semiconductors Or The Like (AREA)
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明はクリーンドラフトの排気状態を管理す
るクリーンドラフトの流量計測装置に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a clean draft flow rate measuring device for managing the exhaust state of a clean draft.
半導体装置の製造工程では、強酸、強アルカ
リ、または弗化水素酸などの薬品による化学エツ
チング加工がしばしば使用される。これらの加工
工程は当然激しい腐蝕性蒸気やミストの発散を伴
うので、上記腐蝕性蒸気やミストを安全かつ確実
に排出しなければならない。しかも作業空間は極
めて清浄な空気で満されている必要があるため
に、通常、いわゆるクリーンドラフトが使用され
る。
In the manufacturing process of semiconductor devices, chemical etching processing using chemicals such as strong acids, strong alkalis, or hydrofluoric acid is often used. Since these processing steps naturally involve the emission of intense corrosive steam and mist, the corrosive steam and mist must be safely and reliably discharged. Moreover, since the work space must be filled with extremely clean air, a so-called clean draft is usually used.
クリーンドラフトは第１図の構成図に示すよう
に、エツチング槽１の上部に高性能のエアフイル
タ２を設け、清浄空気送風ブロア３によつて送り
込まれ上記エアフイルタ２を通過した清浄空気を
絶えず供給しつつ、エツチング槽１からの発生す
る腐蝕性蒸気やミストをクリーンドラフト後面の
排気ダクト４からダンパ５および過装置６を経
て排気ブロア７により強制排気する。上記クリー
ンドラフトの排気流量が適正である場合には、第
２図に示すようにエアフイルタ２を通過した清浄
空気の一部はクリーンドラフトの前面にエアカー
テン８を形成し、かつエツチング槽１から発生す
る腐蝕性蒸気やミスト（図中に破線で示す）はす
べて排気ダクト４から排出される。もし上記排気
流量が過小である場合には、第３図に示すように
エツチング槽１からの腐蝕性蒸気やミストの一部
は清浄空気に混入して工場内に拡散し極めて危険
である。またクリーンドラフトの排気流量が過大
である場合は、第４図に示すように工場内の塵埃
が多い空気をクリーンドラフトに前面開口部から
導入し、この塵埃が多い空気が混入した清浄空気
がエツチング槽１に流入するため、製品に欠陥を
生じ著しく生産性が低下することになる。 As shown in the block diagram of FIG. 1, the clean draft is equipped with a high-performance air filter 2 above an etching tank 1, and constantly supplies clean air that has passed through the air filter 2 and is blown in by a clean air blower 3. At the same time, corrosive steam and mist generated from the etching bath 1 are forcibly exhausted from an exhaust duct 4 at the rear of the clean draft by an exhaust blower 7 via a damper 5 and a filter device 6. When the exhaust flow rate of the clean draft is appropriate, a part of the clean air that has passed through the air filter 2 forms an air curtain 8 in front of the clean draft and is generated from the etching tank 1, as shown in FIG. All corrosive vapors and mist (indicated by broken lines in the figure) are exhausted from the exhaust duct 4. If the exhaust flow rate is too small, some of the corrosive vapor and mist from the etching tank 1 will mix with the clean air and spread into the factory, as shown in FIG. 3, which is extremely dangerous. In addition, if the exhaust flow rate of the clean draft is excessive, as shown in Figure 4, the dusty air from inside the factory is introduced into the clean draft through the front opening, and the clean air mixed with this dusty air is used for etching. Since it flows into the tank 1, it causes defects in the product and significantly reduces productivity.
上記のようにクリーンドラフトを使用するに際
し排気流量の適正化が最重要であるが、多量の強
腐蝕性蒸気やミストを取扱う排気流量の計測に
は、従来信頼性が大きくしかも安価な設備が得ら
れなかつた。 As mentioned above, optimization of the exhaust flow rate is most important when using a clean draft, but conventionally reliable and inexpensive equipment has been used to measure the exhaust flow rate when handling large amounts of highly corrosive steam and mist. I couldn't help it.
本発明は適正な排気状態を維持管理するため、
信頼性が大きく安価なクリーンドラフトの流量計
測装置を得ることを目的とする。
In order to maintain and manage appropriate exhaust conditions, the present invention
The purpose is to obtain a highly reliable and inexpensive clean draft flow rate measuring device.
上記目的を達成するために本発明によるクリー
ンドラフトの流量計測装置は、クリーンドラフト
の排気ダクト内の静圧および全圧、ならびに清浄
空気送風ブロアの吐出圧ともそれぞれ検出して計
測部に導く配管系と、上記清浄空気送風ブロアの
吐出口と排気ダクトとの間に設けた流体抵抗と流
速センサとで構成される流体抵抗ブリツジよりな
る計測部とを備えたものである。
In order to achieve the above object, the clean draft flow rate measuring device according to the present invention detects the static pressure and total pressure in the exhaust duct of the clean draft, as well as the discharge pressure of the clean air blower, and uses a piping system to guide them to the measuring section. and a measuring section consisting of a fluid resistance bridge comprising a fluid resistance and a flow velocity sensor provided between the discharge port of the clean air blower and the exhaust duct.
つぎに本発明の実施例を図面とともに説明す
る。第５図は本発明によるクリーンドラフトの流
量計測装置の一実施例の構成を示す図、第６図は
排気ダクト内のアスピレーシヨン吸引圧（負の動
圧）を利用した配管系と計測部を示す構成図、第
７図は計測部の一具体例の断面図である。第５図
においてクリーンドラフト９内のエツチング槽１
の上部に高性能のエアフイルタ２を設け、該エア
フイルタ２の上部に位置する送風ブロア（図示せ
ず）からの空気の吐出口１０付近に流体抵抗ブリ
ツジ１１の一端に連結された送風ブロア吐出圧検
出管１２を取付け、上記流体抵抗ブリツジ１１の
他端はそれぞれ静圧検出管１３および全圧検出管
１４と連結し、クリーンドラフト９の後部から導
かれた排気ダクト４内に導入されている。
Next, embodiments of the present invention will be described with reference to the drawings. Fig. 5 is a diagram showing the configuration of an embodiment of a clean draft flow rate measuring device according to the present invention, and Fig. 6 shows a piping system and measurement section that utilizes aspiration suction pressure (negative dynamic pressure) in the exhaust duct. FIG. 7 is a sectional view of a specific example of the measuring section. In Fig. 5, the etching tank 1 in the clean draft 9
A high-performance air filter 2 is provided above the air filter 2, and a blower discharge pressure detection device connected to one end of a fluid resistance bridge 11 near the air outlet 10 from a blower (not shown) located above the air filter 2 A pipe 12 is attached, and the other ends of the fluid resistance bridge 11 are connected to a static pressure detection pipe 13 and a total pressure detection pipe 14, respectively, and are introduced into the exhaust duct 4 led from the rear of the clean draft 9.
上記流体抵抗ブリツジ１１は送風ブロア吐出圧
検出管１２から、静圧検出管１３に連結する流体
抵抗raとrcとを有する配管１５および全圧検出管
１４に連結する流体抵抗rbとrdとを有する配管１
６に分れ、上記２つの配管１５および１６におけ
る流体抵抗raとrcとの間のＡ点と流体抵抗rbとrd
との間のＢ点とは流体抵抗rgを有する枝管１７で
結ばれ、該枝管１７内には流速センサ１８が設け
られている。 The fluid resistance bridge 11 is connected to a pipe 15 having fluid resistances r a and r c connected from a blower discharge pressure detection pipe 12 to a static pressure detection pipe 13 and fluid resistances r b and r connected to a total pressure detection pipe 14. Piping 1 with d
The point A between the fluid resistances r a and r c in the two pipes 15 and 16 and the fluid resistances r b and r d
A point B between the two is connected by a branch pipe 17 having a fluid resistance r g , and a flow velocity sensor 18 is provided within the branch pipe 17.
上記クリーンドラフト９の流量計測装置におい
て最も空気の圧力が高いのは送風ブロア吐出圧検
出管１２の送風ブロア吐出圧である。従つて空気
の流れは送風ブロア検出管１２から流体抵抗ブリ
ツジ１１を経て静圧検出管１３および全圧検出管
１４へと流れる。流体抵抗raがrbに等しく、流体
抵抗rcがrdに等しくて排気流量がゼロの場合は、
上記静圧検出管１３の圧力と全圧検出管１４の圧
力とは等しくなり、流体抵抗ブリツジ１１は平衡
状態となり上記枝管１７に空気の流れはなく、上
記吐出圧検出管１２を通過した空気が静圧検出管
１３と全圧検出管１４とから排気ダクト４内に流
れる。 In the flow measuring device of the clean draft 9, the highest air pressure is the blower discharge pressure of the blower discharge pressure detection tube 12. The air flow therefore flows from the blower detection tube 12 through the fluid resistance bridge 11 to the static pressure detection tube 13 and the total pressure detection tube 14. If the fluid resistance r a is equal to r b and the fluid resistance r c is equal to r d and the exhaust flow rate is zero, then
The pressure in the static pressure detection tube 13 and the pressure in the total pressure detection tube 14 become equal, and the fluid resistance bridge 11 is in an equilibrium state, with no air flow in the branch pipe 17 and the air passing through the discharge pressure detection tube 12. flows into the exhaust duct 4 from the static pressure detection tube 13 and the total pressure detection tube 14.
排気ブロア（図示せず）が動作して排気ダクト
４内に第５図の矢印で示す方向に流量が存在する
場合には、全圧検出管１４の圧力は静圧検出管１
３の圧力より動圧だけ高くなり、前記枝管１７に
はＢ点からＡ点に向う空気の流れを生じ、排気ダ
クト４中の流量に関連した通常の空気の流量が流
速センサ１８によつて検出される。 When the exhaust blower (not shown) operates and a flow rate exists in the exhaust duct 4 in the direction indicated by the arrow in FIG.
3 is higher than the pressure at point 3 by the dynamic pressure, an air flow is generated in the branch pipe 17 from point B to point A, and the normal air flow rate related to the flow rate in the exhaust duct 4 is detected by the flow rate sensor 18. Detected.
もし送風ブロア吐出圧検出管１２の圧力よりも
排気ダクト４内の排気全圧力の方が高くなるよう
な場合には、全圧検出管１４から静圧検出管１３
へ向う空気の流れが発生し、流体抵抗ブリツジ１
１の枝管１７においてはＡ点からＢ点に空気が流
れるおそれがある。このようなおそれがある場合
には、第６図に示すように排気ダクト４内におけ
る全圧検出管１４′の先端を排気ダクト４の下流
の方向に曲げ、アスピレーシヨン吸引圧（負の動
圧）を利用するようにすれぱ、クリーンドラフト
９内のエツチング槽１で発生した腐蝕性蒸気やミ
ストが混入した空気を流体抵抗ブリツジ１１が吸
引するのを防ぐことができる。上記のアスピレー
シヨン吸引圧を利用する場合には、流体抵抗ブリ
ツジ１１の枝管１７にＡ点からＢ点に向う適正運
転時とは逆の方向に通常の空気が流れる。 If the total exhaust pressure in the exhaust duct 4 is higher than the pressure in the blower discharge pressure detection tube 12, the pressure in the static pressure detection tube 13 is changed from the total pressure detection tube 14 to the static pressure detection tube 13.
A flow of air is generated towards the fluid resistance bridge 1.
In the first branch pipe 17, there is a risk that air may flow from point A to point B. If there is such a possibility, bend the tip of the total pressure detection tube 14' in the exhaust duct 4 in the downstream direction of the exhaust duct 4, as shown in FIG. By utilizing the pressure), it is possible to prevent the fluid resistance bridge 11 from sucking in air mixed with corrosive vapor or mist generated in the etching tank 1 in the clean draft 9. When using the aspiration suction pressure described above, normal air flows through the branch pipe 17 of the fluid resistance bridge 11 in the opposite direction from point A to point B during proper operation.
なお第７図は計測部における流体抵抗ブリツジ
１１の一具体例を示した断面図であるが、各流体
抵抗ra，rb，rc，rdはそれぞれニードル弁を用い
て抵抗値の調整ができるようにしている。（枝管
１７の流体抵抗rgは省略してある。）同図におけ
る１９，２０，２１はそれぞれ吐出圧検出管、静
圧検出管、全圧検出管の連結口である。 Note that FIG. 7 is a sectional view showing a specific example of the fluid resistance bridge 11 in the measurement section, and the resistance values of each of the fluid resistances r a , r b , r c , and r d are adjusted using needle valves. We are making it possible to do so. (The fluid resistance r g of the branch pipe 17 is omitted.) Reference numerals 19, 20, and 21 in the figure are connection ports for the discharge pressure detection pipe, the static pressure detection pipe, and the total pressure detection pipe, respectively.
上記のように実施例に示すクリーンドラフト９
の流体計測装置は計測部の流体抵抗ブリツジ１１
に腐蝕性蒸気やミストが混入した空気が流入する
おそれがないため、上記流体抵抗ブリツジ１１の
枝管１７に挿入する流速センサ１８はその耐蝕性
を考慮する必要がなく、排気ダクト１４および排
気ダクト４内に挿入される配管だけを耐蝕性があ
るものにすればよい。 Clean draft 9 shown in the example above
The fluid measuring device has a fluid resistance bridge 11 in the measuring section.
Since there is no risk of air mixed with corrosive vapor or mist flowing into the air, there is no need to consider the corrosion resistance of the flow rate sensor 18 inserted into the branch pipe 17 of the fluid resistance bridge 11, and the exhaust duct 14 and the exhaust duct It is only necessary to make only the piping inserted into the pipe 4 corrosion-resistant.
なお排気ダクト４の全圧が常に大気圧より負圧
であるならば、（ほとんどの場合はこの条件が成
立する）第５図および第６図における送風ブロア
吐出圧検出管１２を送風ブロア吐出口１０近傍に
接続することなく、大気中に開放してもよい。 Note that if the total pressure of the exhaust duct 4 is always negative than atmospheric pressure (this condition holds in most cases), the blower discharge pressure detection pipe 12 in FIGS. 5 and 6 is connected to the blower outlet. 10 may be opened to the atmosphere without being connected to the vicinity.
上記のように本発明によるクリーンドラフトの
流量計測装置は、クリーンドラフトの排気ダクト
内の静圧および全圧、ならびに清浄空気送風ブロ
アの吐出圧とをそれぞれ検出して計測部に導く配
管系と、上記清浄空気送風ブロアの吐出口と排気
ダクトとの間に設けた流体抵抗と流速センサとで
構成される流体抵抗ブリツジよりなる計測部とを
備えたことにより、腐蝕性蒸気やミストが混入し
た空気を上記流体抵抗ブリツジ内に流さないた
め、排気ダクトおよび排気ダクト内に挿入された
配管だけを耐蝕性があるものにすれば、通常の流
速センサを用いて排気状態を維持管理することが
でき、極めて信頼性が高く、かつ安価なクリーン
ドラフトの流量計測装置を得ることができる。
As described above, the clean draft flow rate measuring device according to the present invention includes a piping system that detects the static pressure and total pressure in the exhaust duct of the clean draft, and the discharge pressure of the clean air blower and guides them to the measurement section. A measuring section consisting of a fluid resistance bridge consisting of a fluid resistance and a flow velocity sensor provided between the outlet of the clean air blower and the exhaust duct allows the air to be mixed with corrosive vapor or mist. In order to prevent the flow of air into the fluid resistance bridge, if only the exhaust duct and the piping inserted into the exhaust duct are made corrosion-resistant, the exhaust condition can be maintained and managed using a normal flow rate sensor. An extremely reliable and inexpensive clean draft flow rate measuring device can be obtained.
第１図は従来のクリーンドラフトの構成図、第
２図はクリーンドラフトの排気流量が適正な場合
の空気の流れを示す説明図、第３図は上記排気流
量が過小な場合の空気の流れを示す説明図、第４
図は上記排気流量が過大な場合の空気の流れを示
す説明図、第５図は本発明によるクリーンドラフ
トの流量計測装置の一実施例の構成を示す図、第
６図は上記実施例における排気ダクト内のアスピ
レーシヨン吸引圧を利用した配管系と計測部を示
す構成図、第７図は計測部の一具体例を示す断面
図である。
４……排気ダクト、９……クリーンドラフト、
１０……清浄空気送風ブロアの吐出口、１１……
流体抵抗ブリツジ、１２……送風ブロア吐出圧検
出管、１３……静圧検出管、１４……全圧検出
管、１７……枝管、１８……流速センサ、ra，
rb，rc，rd，rg……流体抵抗。
Figure 1 is a configuration diagram of a conventional clean draft, Figure 2 is an explanatory diagram showing the air flow when the exhaust flow rate of the clean draft is appropriate, and Figure 3 is an illustration of the air flow when the exhaust flow rate is too low. Explanatory diagram showing, No. 4
The figure is an explanatory diagram showing the air flow when the above exhaust flow rate is excessive. Figure 5 is a diagram showing the configuration of an embodiment of the clean draft flow rate measuring device according to the present invention. Figure 6 is the exhaust flow in the above embodiment. FIG. 7 is a configuration diagram showing a piping system and a measuring section that utilize aspiration suction pressure in a duct, and FIG. 7 is a sectional view showing a specific example of the measuring section. 4...Exhaust duct, 9...Clean draft,
10... Discharge port of clean air blower, 11...
Fluid resistance bridge, 12... Blower discharge pressure detection tube, 13... Static pressure detection tube, 14... Total pressure detection tube, 17... Branch pipe, 18... Flow rate sensor, r a ,
r b , r c , r d , r g ...fluid resistance.
Claims (1)
び全圧、ならびに清浄空気送風ブロアの吐出圧と
をそれぞれ検出して計測部に導く配管系と、上記
清浄空気送風ブロアの吐出口と排気ダクトとの間
に設けた、流体抵抗と流速センサとで構成される
流体抵抗ブリツジよりなる計測部とを備えたクリ
ーンドラフトの流量計測装置。 ２ 上記流体抵抗ブリツジは、流体抵抗ra，rb，
rc，rd、rgと流速センサとよりなり、ra＝rb，rc＝
rdとし、raとrcおよびrbとrdをそれぞれ直列に接
続し、上記raの他端とrbの他端とを清浄空気送風
ブロアの吐出口に接続し、rcおよびrdの他端を排
気ダクトの静圧側および全圧側にそれぞれ接続
し、かつraとrcとの間およびrbとrdとの間を流体
抵抗rgを有する枝管で連結して、該枝管の中の流
量を計測する流速センサを上記枝管中に設けたこ
とを特徴とする特許請求の範囲第１項に記載され
たクリーンドラフトの流量計測装置。 ３ 上記流体抵抗は接続用管の流体抵抗であるこ
とを特徴とする特許請求の範囲第１項または第２
項に記載されたクリーンドラフトの流量計測装
置。 ４ 上記流速センサはサーミスタを用いた熱伝導
形の風速センサであることを特徴とする特許請求
の範囲第１項乃至第３項のいずれかに記載された
クリーンドラフトの流量計測装置。 ５ 上記全圧は、排気ダクトの下流方向に向けて
開口した圧力検出管により検出されるアスピレー
シヨン圧であることを特徴とする特許請求の範囲
第１項乃至第４項のいずれかに記載されたクリー
ンドラフトの流量計測装置。[Scope of Claims] 1. A piping system that detects the static pressure and total pressure in the exhaust duct of the clean draft and the discharge pressure of the clean air blower and leads them to the measurement unit, and a discharge port of the clean air blower. A clean draft flow rate measurement device comprising a measurement unit consisting of a fluid resistance bridge that is provided between the air resistance and an exhaust duct and is composed of a fluid resistance bridge and a flow velocity sensor. 2 The fluid resistance bridge described above has fluid resistances r a , r b ,
It consists of r c , r d , r g and a flow rate sensor, and r a = r b , r c =
r d , connect r a and r c and r b and r d in series, connect the other end of r a and the other end of r b to the outlet of the clean air blower, and connect r c and r d in series. The other end of r d is connected to the static pressure side and the total pressure side of the exhaust duct, and a branch pipe having a fluid resistance r g is connected between r a and r c and between r b and r d . 2. The clean draft flow measuring device according to claim 1, further comprising a flow rate sensor provided in the branch pipe to measure the flow rate in the branch pipe. 3. Claim 1 or 2, wherein the fluid resistance is the fluid resistance of a connecting pipe.
The clean draft flow rate measuring device described in section. 4. The clean draft flow rate measuring device according to any one of claims 1 to 3, wherein the flow rate sensor is a heat conduction type wind rate sensor using a thermistor. 5. According to any one of claims 1 to 4, the total pressure is an aspiration pressure detected by a pressure detection tube opened toward the downstream direction of the exhaust duct. Clean draft flow measuring device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22858183A JPS60120219A (en) | 1983-12-05 | 1983-12-05 | Flow-rate measuring device for clean draft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22858183A JPS60120219A (en) | 1983-12-05 | 1983-12-05 | Flow-rate measuring device for clean draft |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60120219A JPS60120219A (en) | 1985-06-27 |
| JPS6338647B2 true JPS6338647B2 (en) | 1988-08-01 |
Family
ID=16878602
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22858183A Granted JPS60120219A (en) | 1983-12-05 | 1983-12-05 | Flow-rate measuring device for clean draft |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60120219A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6783193B2 (en) * | 2017-06-14 | 2020-11-11 | 株式会社日立産機システム | Safety cabinet |
| CN107631765B (en) * | 2017-09-05 | 2020-07-07 | 合肥科迈捷智能传感技术有限公司 | A kind of differential pressure flowmeter water treatment method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53143361A (en) * | 1977-05-20 | 1978-12-13 | Oval Eng Co Ltd | Flow meter for von k*arman*s vortex street |
| JPS5633565U (en) * | 1979-08-23 | 1981-04-02 |
-
1983
- 1983-12-05 JP JP22858183A patent/JPS60120219A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60120219A (en) | 1985-06-27 |
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