JPH026836A - Slow-vent valve and its control method - Google Patents
Slow-vent valve and its control methodInfo
- Publication number
- JPH026836A JPH026836A JP15658688A JP15658688A JPH026836A JP H026836 A JPH026836 A JP H026836A JP 15658688 A JP15658688 A JP 15658688A JP 15658688 A JP15658688 A JP 15658688A JP H026836 A JPH026836 A JP H026836A
- Authority
- JP
- Japan
- Prior art keywords
- gas
- valve
- pressure vessel
- pressure
- valve bodies
- 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.)
- Granted
Links
- 238000000034 method Methods 0.000 title abstract description 15
- 239000000428 dust Substances 0.000 claims abstract 3
- 230000006837 decompression Effects 0.000 claims description 21
- 239000002245 particle Substances 0.000 description 15
- 238000010586 diagram Methods 0.000 description 11
- 230000000694 effects Effects 0.000 description 3
- 238000013022 venting Methods 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 241000270295 Serpentes Species 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J3/00—Processes of utilising sub-atmospheric or super-atmospheric pressure to effect chemical or physical change of matter; Apparatus therefor
- B01J3/002—Component parts of these vessels not mentioned in B01J3/004, B01J3/006, B01J3/02 - B01J3/08; Measures taken in conjunction with the process to be carried out, e.g. safety measures
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Lift Valve (AREA)
Abstract
Description
【発明の詳細な説明】
〔(既 要〕
減圧状態の減圧室に気体を流入して大気圧にする機器及
びその制御方法に関し、
減圧室に流入させる気体の流量を可変にして大気圧に到
達する時間を短縮し、減圧室内でのパーティクルの浮遊
を防止することが可能な、スローベント用バルブ及びそ
の制御方法の提供を目的とし、
減圧室に気体を流入させるのに用いるバルブであって、
流入気体を一時収容する圧力容器と、該圧力容器の前記
流入気体の流入側及び流出側に配設した、前記圧力容器
と外部とを遮断する複数の弁体と、該複数の弁体の開閉
を任意に制御する制御装置とを具備するよう構成する。[Detailed Description of the Invention] [(Already required)] This invention relates to a device and a control method thereof, in which gas flows into a decompression chamber in a reduced pressure state to bring it to atmospheric pressure, and the flow rate of the gas flowing into the decompression chamber is varied to reach atmospheric pressure. The purpose of the present invention is to provide a slow vent valve and a control method thereof, which can reduce the time required for depressurization and prevent particles from floating in a decompression chamber, and the present invention provides a valve used to allow gas to flow into a decompression chamber,
A pressure vessel that temporarily accommodates inflow gas, a plurality of valve bodies disposed on the inflow side and outflow side of the inflow gas of the pressure vessel, which isolates the pressure vessel from the outside, and opening/closing of the plurality of valve bodies. and a control device that arbitrarily controls.
本発明は、真空を利用する装置に係り、特に減圧状態の
減圧室に気体を流入して大気圧にする機器及びその制御
方法に関するものである。The present invention relates to an apparatus that utilizes vacuum, and more particularly to a device that causes gas to flow into a reduced pressure chamber to bring it to atmospheric pressure, and a method for controlling the same.
近年、真空を利用する装置において、減圧状態の減圧室
に気体を流入して大気圧にする場合に、この減圧室に流
入する気体により減圧室内のパーティクルが室内に浮遊
し、この減圧室内で処理した製品の表面に付着し、製品
の品質を劣化させる障害が発生している。In recent years, in equipment that utilizes vacuum, when gas flows into a decompression chamber in a reduced pressure state to bring it to atmospheric pressure, the gas flowing into the decompression chamber causes particles in the decompression chamber to float inside the chamber, causing them to be processed in the decompression chamber. It adheres to the surface of the product and causes problems that deteriorate the quality of the product.
以上のような状況から減圧室に流入する気体により減圧
室内のパーティクルが室内に浮遊しないように、減圧室
に気体を流入させることが可能な機器及び方法が要望さ
れている。Under the above circumstances, there is a need for a device and method that can allow gas to flow into a reduced pressure chamber so that particles in the reduced pressure chamber are not suspended due to the gas flowing into the reduced pressure chamber.
従来の減圧室に気体を流入させるのに用いる機器及び方
法について第6図〜第8図により説明する。The equipment and method used to flow gas into a conventional vacuum chamber will be explained with reference to FIGS. 6-8.
第6図は従来の真空を用いる装置の構成図である。図に
おいて、減圧状態にある減圧室16を大気圧にする場合
は、排気側のバルブ18を閉じて気体流入側のバルブ1
7を開けると、非常に圧力の高い気体が減圧室16内に
流入する。FIG. 6 is a block diagram of a conventional apparatus using vacuum. In the figure, when the pressure reduction chamber 16 in a reduced pressure state is brought to atmospheric pressure, the exhaust side valve 18 is closed and the gas inflow side valve 1 is closed.
7, a very high pressure gas flows into the vacuum chamber 16.
このようにして気体を減圧室16内に流入すると、減圧
室16内の多量のパーティクルが浮遊し、減圧室16内
の処理済の製品の表面に付着し、製品の品質を低下させ
、製品歩留りを低下させている。When the gas flows into the vacuum chamber 16 in this way, a large amount of particles float inside the vacuum chamber 16 and adhere to the surface of the processed product inside the vacuum chamber 16, reducing the quality of the product and reducing the product yield. is decreasing.
このような状態になるのを防止する方法として、流入気
体の最大流量を制限するために配管内の気体の流路を絞
るように、配管内に第7図に示すような絞り孔19aを
有するレストリクター19を設けたり、或いは流量の微
量調整が可能なニードルバルブをバルブ17の近傍に設
け、減圧室16内に流入する気体の流量を絞るという方
法を採用している。As a method of preventing such a state from occurring, a restriction hole 19a as shown in FIG. 7 is provided in the piping so as to restrict the gas flow path in the piping in order to limit the maximum flow rate of the inflowing gas. A method is adopted in which a restrictor 19 is provided or a needle valve capable of minutely adjusting the flow rate is provided near the valve 17 to restrict the flow rate of the gas flowing into the decompression chamber 16.
このような方法でベントを行った場合の減圧室16の内
圧p、が時間の経過に従って大気圧P。に変化する状況
を第8図に示す。When venting is performed in this manner, the internal pressure p of the decompression chamber 16 becomes atmospheric pressure P as time passes. Figure 8 shows the changing situation.
図において、流体圧力とは流入気体の分子がパーティク
ルとの衝突によってパーティクルに与える運動エネルギ
ーをさしている。In the figure, fluid pressure refers to the kinetic energy that molecules of the inflowing gas give to particles when they collide with the particles.
気体中を飛びまわる分子の平均速度は、気体の種類と温
度を特定した場合は一定と考えられるので、気体の分子
相互或いは気体の分子とパーティクルとの衝突を考えた
場合、問題となるのは流入気体分子とパーティクルとが
衝突する確率であると考えられる。The average speed of molecules flying around in a gas is considered to be constant when the type of gas and temperature are specified, so when considering collisions between gas molecules or between gas molecules and particles, the problem is the inflow. This is considered to be the probability of collision between gas molecules and particles.
つまり減圧状態で気体分子が他の分子に衝突せずに移動
可能な距離(この距離を平均自由行程と称する)は数m
7秒、また、大気圧中での平均自由行程は数cr−/秒
となり、減圧状態が大気圧に近づくにつれて、分子が他
の分子に衝突せずに移動できる距離は小さくなります。In other words, the distance that gas molecules can travel under reduced pressure without colliding with other molecules (this distance is called the mean free path) is several meters.
7 seconds, and the mean free path in atmospheric pressure is several cr-/second, and as the reduced pressure state approaches atmospheric pressure, the distance a molecule can travel without colliding with other molecules becomes smaller.
別の表現をすれば、室内圧が最低の減圧状態にある場合
には、流入気体が他の分子に妨げられずにパーティクル
と衝突する確率は最大で、大気圧に近すけば近ずくほど
パーティクルと衝突する確率は低くなると考えられます
。In other words, when the room pressure is at its lowest, the probability that the incoming gas will collide with particles without being hindered by other molecules is maximum; the closer the pressure is to atmospheric pressure, the more particles The probability of collision is thought to be low.
以上説明の従来の減圧室に気体を流入させるのに用いる
機器及び方法においては、気体の流路が絞られていない
場合には、第8図の流体圧力の曲線の時間が0に近い時
点で、減圧室に流入する気体により減圧室内のパーティ
クルが室内に浮遊し、この減圧室内で処理した製品の表
面に付着するという問題点があり、減圧室内のパーティ
クルが浮遊しないように気体の流路を終始一定に絞ると
、減圧室内圧を大気圧にするのに非常に長時間を必要と
し、実用に供することが出来ないという問題点があった
。In the conventional equipment and method used to flow gas into the decompression chamber described above, when the gas flow path is not restricted, the time of the fluid pressure curve in Fig. 8 is close to 0. However, there is a problem in that the gas flowing into the vacuum chamber causes particles in the vacuum chamber to float inside the chamber and adhere to the surfaces of products processed in the vacuum chamber. If the pressure is kept constant from beginning to end, it takes a very long time to bring the pressure inside the vacuum chamber to atmospheric pressure, which poses a problem that it cannot be put to practical use.
本発明は以上のような状況から減圧室に流入させる気体
の流量を可変にして大気圧に到達する時間を短縮し、減
圧室内でのパーティクルの浮遊を防止することが可能な
、スローベント用パルプへびその制御方法の提供を目的
としたものである。The present invention provides a pulp for slow venting that can reduce the time required for the gas to reach atmospheric pressure by varying the flow rate of the gas flowing into the decompression chamber, thereby preventing particles from floating in the decompression chamber. The purpose of this study is to provide a method for controlling snakes.
上記問題点は、減圧室に気体を流入させるのに用いるバ
ルブであって、流入気体を一時収容する圧力容器と、こ
の圧力容器の流入気体の流入側及び流出側に配設した、
この圧力容器と外部とを遮断する複数の弁体と、この複
数の弁体の開閉を任意に制御する制御装置とを具備する
本発明によるスローベント用バルブ及びその制御方法に
よって解決される。The above problem lies in the fact that the valve used to allow gas to flow into the decompression chamber includes a pressure vessel that temporarily accommodates the inflow gas, and a valve disposed on the inflow and outflow sides of the inflow gas of this pressure vessel.
The problem is solved by the slow vent valve and its control method according to the present invention, which includes a plurality of valve bodies that isolate the pressure vessel from the outside, and a control device that arbitrarily controls opening and closing of the plurality of valve bodies.
即ち本発明においては、第1図に示す気体の流入側の弁
体2と流出側の弁体3の開閉を、制御装置によってつぎ
の五つの基本動作パターンA−Eの内の、B−Eの四つ
の基本動作パターンを組み合わせた第2図に示すタイミ
ングチャートの1サイクルの動作の、単位時間当たりの
回数を増減させたり、弁体2及び弁体3の開閉のタイミ
ングを変えたりすることにより、圧力容器内に流入する
気体の量を制御して減圧室内に流入する気体の壇を制限
し、減圧室内におけるパーティクルの浮遊を防止するこ
とが可能となる。That is, in the present invention, the control device controls the opening and closing of the valve body 2 on the gas inflow side and the valve body 3 on the gas outflow side shown in FIG. By increasing or decreasing the number of operations per unit time of one cycle of the timing chart shown in FIG. 2, which combines the four basic operation patterns of By controlling the amount of gas flowing into the pressure vessel, it is possible to limit the amount of gas flowing into the reduced pressure chamber, thereby preventing particles from floating in the reduced pressure chamber.
A、弁体2及び弁体3の両方を閉じる。A. Close both valve body 2 and valve body 3.
B、弁体2を開き、圧力容器4内に気体を流入させる。B. Open the valve body 2 and let gas flow into the pressure vessel 4.
C0弁体2を閉じる。Close the C0 valve body 2.
D、弁体2を閉じて圧力容器4を流入気体と完全に遮断
した状態で、弁体3を開く。D. Open the valve body 3 with the valve body 2 closed to completely cut off the pressure vessel 4 from incoming gas.
E、圧力容器4内の気体が減圧室6に完全に流入した後
、弁体3を閉じる。E. After the gas in the pressure vessel 4 has completely flowed into the decompression chamber 6, the valve body 3 is closed.
このように、圧力容器4に流入する気体の量を時間の経
過に従って増加していくことにより、減圧室内における
パーティクルの浮遊を防止しながら、減圧室が大気圧に
到達する時間を従来の終始一定の絞りにより行う方法に
比して、短縮することが可能となる。In this way, by increasing the amount of gas flowing into the pressure vessel 4 over time, particles are prevented from floating in the vacuum chamber, and the time it takes for the vacuum chamber to reach atmospheric pressure is kept constant from beginning to end, unlike conventional methods. This makes it possible to shorten the time compared to the method using diaphragm.
以下第1図及び第3図〜第5図について本発明の一実施
例を説明する。An embodiment of the present invention will be described below with reference to FIG. 1 and FIGS. 3 to 5.
第3図は本発明による一実施例の構成図を示す図であり
、気体の流入側のバルブ7と減圧室6との間に本発明の
スローベント用バルブを配設しており、真空計10及び
記録計11はバルブ9を介して減圧室6と接続され、減
圧室6内の状況を指示或いは記録できるようになってい
る。FIG. 3 is a diagram showing a configuration diagram of an embodiment according to the present invention, in which the slow vent valve of the present invention is disposed between the valve 7 on the gas inflow side and the decompression chamber 6, and the vacuum gauge 10 and recorder 11 are connected to the decompression chamber 6 via the valve 9, and are capable of indicating or recording the situation inside the decompression chamber 6.
第1図に要部詳細を示すこのスローベント用バルブの弁
体2及び弁体3としては、電磁方式により駆動されるも
のを用いた。これらの弁体のタイミング制御は制御装置
5により行っている。The valve body 2 and the valve body 3 of this slow vent valve, the main parts of which are shown in detail in FIG. 1, were driven by an electromagnetic system. Timing control of these valve bodies is performed by a control device 5.
本発明の一実施例のスローベント用バルブの弁体2及び
弁体3のタイミングチャートを第4図に、流入気体の圧
力変化を第5図に示す。FIG. 4 shows a timing chart of the valve bodies 2 and 3 of a slow vent valve according to an embodiment of the present invention, and FIG. 5 shows pressure changes of inflow gas.
第4図のタイミングチャートに示すように、弁体のタイ
ミングは大別して3種類に分類できる。As shown in the timing chart of FIG. 4, the timing of the valve body can be roughly classified into three types.
Typel:弁体2及び弁体3の開閉タイミングはΔt
、のアイソレートタイムで区切られ、各々の弁体の開放
状態は完全に独立している。Type: Opening/closing timing of valve body 2 and valve body 3 is Δt
, and the open state of each valve body is completely independent.
Type2:弁体2及び弁体3の開閉タイミングはΔ1
.のオーバーランブタイムで同期しながら開閉する。Type 2: Opening/closing timing of valve body 2 and valve body 3 is Δ1
.. Opens and closes in synchronization with overrun time.
Type3:弁体2及び弁体3が同時に開閉する。Type 3: Valve body 2 and valve body 3 open and close at the same time.
これらの開閉パターンを時間で制御し、Type t−
+Typ e 2−Typ e 3と移っていっても良
い、また、TypelのΔt1のアイソレートタイムを
変化させて次第に短くし、弁体2及び弁体3のタイミン
グを非同期−半同期一同朋と変化する一連の動作にして
も良い。These opening and closing patterns are controlled by time, and Type t-
+Type e 2 - Type e 3 may be changed, or the isolation time of Δt1 of Type may be changed to gradually shorten it, and the timing of valve element 2 and valve element 3 may be changed from asynchronous to semi-synchronous. It may be a series of actions.
なお、弁体の駆動方式としては、上記の電磁方式の他に
空圧方式を用いることも可能である。In addition to the electromagnetic method described above, it is also possible to use a pneumatic method to drive the valve body.
また、スローベント用バルブ内の圧力容器4の容積を弁
座lの一部をねじ込み構造にし、圧力容器4の容積を変
化させることを可能にし、減圧室6の容積に適合させる
ことも可能である。In addition, the volume of the pressure vessel 4 inside the slow vent valve can be changed by screwing a part of the valve seat l into a structure that allows the volume of the pressure vessel 4 to be changed to match the volume of the decompression chamber 6. be.
以上の説明から明らかなように、本発明によれば筒車な
構成の複数の弁体と圧力容器とを有するスローベント用
バルブを設けることにより、減圧室内部におけるパーテ
ィクルの製品の表面への付着を、従来の付着を100と
すると2に減少させることが可能となり、製品の品質を
著しく向上させることが可能となる等の利点があり、著
しい経済的及び、信頼性向上の効果が期待でき工業的に
は極めて有用なものである。As is clear from the above description, according to the present invention, by providing a slow vent valve having a plurality of valve elements having an hour wheel configuration and a pressure vessel, particles can be prevented from adhering to the surface of the product inside the decompression chamber. It is possible to reduce the conventional adhesion to 2 compared to 100, which has the advantage of significantly improving the quality of the product, and can be expected to have significant economic and reliability effects. It is extremely useful.
第1図は本発明のスローベント用バルブの要部詳細図、
第2図は本発明のスローベント用バルブの作動タイミン
グチャート、
第3図は本発明による一実施例の構成図、第4図は本発
明による一実施例のスローベント用バルブのタイミング
チャート、
第5図は本発明による一実施例の特性を示す図、第6図
は従来の真空を用いる装置の構成図、第7図はレストリ
クターを示す図、
第8図は従来の方法でベントした場合の特性を示す図、
である。
図において、
1は弁座、
2は弁体、
3は弁体、
4は圧力容器、
5は制御装置、
6は減圧室、
7はハ“ルブ、
8はバルブ、
9はパルプ、
10は真空計、
11は記録計、
本発明のスローベント用バルブの要部詳lI図第1図
本発明による一実施例の構成図
第3図
時1JIt
本発明のスローベント用バルブの作動タイミングチャー
ト第 2−
Δ仁。
ΔLゆ
本発明による一実施例のスローベント用バルブのタイミ
ングチャート第4図
O
時間
本発明による一実施例の特性を示す図
書
図
従来の真空を用いる装置の構成図
(al
平
面
図
(bl
側断面図
レストリクターを示す図
第
図
時間
従来の方法でベントした場合の特性を示す2舅
関FIG. 1 is a detailed view of the main parts of the slow vent valve of the present invention, FIG. 2 is an operation timing chart of the slow vent valve of the present invention, FIG. 3 is a configuration diagram of an embodiment of the present invention, and FIG. 4 5 is a timing chart of a slow vent valve according to an embodiment of the present invention, FIG. 5 is a diagram showing the characteristics of an embodiment of the present invention, FIG. 6 is a configuration diagram of a conventional vacuum device, and FIG. 7 is a diagram showing the characteristics of an embodiment of the present invention. Figure 8 is a diagram showing the restrictor, and Figure 8 is a diagram showing the characteristics when venting using the conventional method. In the figure, 1 is a valve seat, 2 is a valve body, 3 is a valve body, 4 is a pressure vessel, 5 is a control device, 6 is a pressure reduction chamber, 7 is a halve, 8 is a valve, 9 is pulp, 10 is a vacuum 11 is a recorder; Figure 1 is a detailed diagram of the main parts of the slow vent valve of the present invention. Figure 3 is a configuration diagram of an embodiment of the present invention. - ΔN. ΔL Yu Timing chart of a slow vent valve according to an embodiment of the present invention. (bl Side sectional view showing the restrictor.
Claims (2)
ブであって、 流入気体を一時収容する圧力容器(4)と、該圧力容器
(4)の前記流入気体の流入側及び流出側に配設した、
前記圧力容器(4)と外部とを遮断する複数の弁体(2
、3)と、該複数の弁体(2、3)の開閉を任意に制御
する制御装置(5)と、 を具備することを特徴とするスローベント用バルブ。(1) A valve used to allow gas to flow into the decompression chamber (6), which includes a pressure vessel (4) that temporarily stores the inflow gas, and an inflow side and an outflow side of the inflow gas of the pressure vessel (4). placed in
A plurality of valve bodies (2) that shut off the pressure vessel (4) and the outside
, 3); and a control device (5) that arbitrarily controls opening and closing of the plurality of valve bodies (2, 3).
装置(5)により前記複数の弁体(2、3)の開閉を制
御し、気体流入時の塵埃の浮動を抑制することを特徴と
するスローベント用バルブの制御方法。(2) The control device (5) of the slow vent valve according to claim 1 controls opening and closing of the plurality of valve bodies (2, 3) to suppress floating of dust when gas flows in. How to control a slow vent valve.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP63156586A JPH0815543B2 (en) | 1988-06-24 | 1988-06-24 | Slow vent valve and control method thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP63156586A JPH0815543B2 (en) | 1988-06-24 | 1988-06-24 | Slow vent valve and control method thereof |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH026836A true JPH026836A (en) | 1990-01-11 |
JPH0815543B2 JPH0815543B2 (en) | 1996-02-21 |
Family
ID=15631003
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP63156586A Expired - Fee Related JPH0815543B2 (en) | 1988-06-24 | 1988-06-24 | Slow vent valve and control method thereof |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0815543B2 (en) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6236737A (en) * | 1985-08-09 | 1987-02-17 | Canon Inc | Optical system driver |
-
1988
- 1988-06-24 JP JP63156586A patent/JPH0815543B2/en not_active Expired - Fee Related
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6236737A (en) * | 1985-08-09 | 1987-02-17 | Canon Inc | Optical system driver |
Also Published As
Publication number | Publication date |
---|---|
JPH0815543B2 (en) | 1996-02-21 |
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