JPH0379882A - Flow control valve - Google Patents

Abstract

PURPOSE:To suppress the generation of cavitation by forming a through passage at a fixed valve stem, further forming communicating passages to be communicated with the through passage at the slightly opened time of a valve body on the primary and secondary sides of the valve body, and providing a guide plate on the valve body secondary side. CONSTITUTION:When a valve body 4 is slightly opened, the through passage 8 of a fixed valve stem 3 corresponds with the communicating passages 9, 10 on the primary and secondary sides of the valve body 4, so that a fluid on the primary side of the valve body 4 flows out to the secondary side through the communicating passage 9, the through passage 8 and the communicating passage 10. When the valve body 4 is in the closed state, the phase of the through passage 8 and the communicating passages 9, 10 is dislocated so as to block the primary and secondary sides. A guide plate 11 on the secondary side of the valve body 4 is provided with a fluid passage 12 of the specified cross sectional area formed between the guide plate 11 and the valve body secondary side surface so as to guide the fluid on the primary side at the slightly opened time from the communicating passage 10 to the peripheral part 4a on the valve body secondary side. As a result, the fluid from the guide plate 11 is added to the fluid flowing out to the secondary side from between the valve body peripheral part 4a and the valve casing 2, thereby preventing the generation of the negative pressure state as well as suppressing the generation of cavitation.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、流量制御弁に関し、特に弁体の２次側に発生
するキャビテーションの抑制効果を増強した流量制御弁
に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flow control valve, and more particularly to a flow control valve that has an enhanced effect of suppressing cavitation occurring on the secondary side of a valve body.

〔従来の技術〕[Conventional technology]

従来、流量制御弁（バタフライ弁）の絞り運転（小開度
）時には、弁体の２次側（下流側）にキャビテーション
が発生し、弁体を損傷する慮があるので、特開昭５７−
１５７８６６号公報に示されるように、弁体の周縁部に
櫛歯状突起を配設して、流体の流れを分割案内し、突起
間のスリットから流体を細かいジェット流に変え、弁体
の下流側で発生するキャビテーションを分散するととも
に、キャビテーションの成長、及び該キャビテーション
による騒音や振動を極力抑制している。Conventionally, during throttling operation (small opening) of a flow control valve (butterfly valve), cavitation occurs on the secondary side (downstream side) of the valve body, and there is a risk of damaging the valve body.
As shown in Japanese Patent No. 157866, comb-like protrusions are provided on the periphery of the valve body to divide and guide the flow of fluid, converting the fluid into a fine jet flow through the slits between the protrusions, and distributing the fluid downstream of the valve body. In addition to dispersing the cavitation that occurs on the side, the growth of cavitation and the noise and vibration caused by the cavitation are suppressed as much as possible.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

しかしながら、上述の構造のバタフライ弁であっても、
キャビテーションを抑制する効果が必ずしも充分ではな
く、さらに耐キヤビテーシヨン特性に優れた流量制御弁
の開発が望まれていた。However, even with the butterfly valve having the above structure,
The effect of suppressing cavitation is not necessarily sufficient, and there has been a desire to develop a flow control valve that has excellent cavitation resistance.

そこで本発明は、キャビテーションの抑制効果を増強し
、絞り運転を良好に行なえるとともに、低騒音、低振動
化を図った流量制御弁を提供することを目的としている
。SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a flow control valve that can enhance the cavitation suppressing effect, perform throttling operation well, and achieve low noise and vibration.

〔課題を解決するための手段〕[Means to solve the problem]

上記した目的を達成するために、本発明の流量制御弁は
、弁箱に設けた固定弁軸に回動可能に支持した弁体を回
動用弁軸により開閉する流量制御弁において、前記固定
弁軸に径方向に貫通する貫通路を形成し、弁体の１次側
及び弁体の２次側に、該弁体が小開度の時に前記弁軸の
貫通路に連通ずる連通路をそれぞれ形成するとともに、
弁体の２次側に、前記連通路から流出する流体を弁体２
次側の外周部に案内する案内板を設けたことを特徴とし
ている。In order to achieve the above object, the flow control valve of the present invention is a flow control valve in which a valve body rotatably supported on a fixed valve shaft provided in a valve box is opened and closed by a rotating valve shaft. A through passage passing through the shaft in a radial direction is formed, and communication passages are provided on the primary side of the valve body and the secondary side of the valve body, respectively, to communicate with the through passage of the valve shaft when the valve body is at a small opening degree. Along with forming;
The fluid flowing out from the communication passage is transferred to the secondary side of the valve body 2.
It is characterized by the provision of a guide plate on the outer periphery of the next side.

〔作　用〕[For production]

上記のごとく構成することにより、絞り運転の小開度時
に１次側の流体が弁体１次側の連通路。By configuring as described above, the fluid on the primary side flows into the communication path on the primary side of the valve element when the opening degree is small during throttling operation.

固定弁軸の貫通路、弁体２次側の連通路から案内板を介
して弁体２次側の外周部に案内されるため、弁体外周部
の負圧状態が緩和されてキャビテーションが抑制される
。Since it is guided from the fixed valve shaft through passage and the communication passage on the secondary side of the valve body to the outer circumference of the secondary side of the valve body via the guide plate, the negative pressure state on the outer circumference of the valve body is alleviated and cavitation is suppressed. be done.

〔実施例〕〔Example〕

以下、本発明を図面に示す一実施例に基づいて、さらに
詳細に説明する。Hereinafter, the present invention will be explained in more detail based on an embodiment shown in the drawings.

流量制御弁１は、第１図において左側、第３図乃至第５
図において下側を１次側（上流側）にして、管路（図示
せず）に介設される円筒状の弁箱２に設けた固定弁軸３
に回動可能に支持した弁体４を、固定弁軸３の上方に弁
箱２を貫通して設けた回動用弁軸５により開閉するもの
である。The flow control valve 1 is located on the left side in FIG. 1, and on the left side in FIGS.
A fixed valve shaft 3 installed in a cylindrical valve box 2 interposed in a pipeline (not shown) with the lower side as the primary side (upstream side) in the figure.
A valve body 4 rotatably supported is opened and closed by a rotating valve shaft 5 provided above a fixed valve shaft 3 and penetrating the valve body 2.

弁体４には、開弁作動方向の反対側の面、即ち第４図及
び第５図において、弁軸を中心として左側では上流側と
なる下方の面、弁軸の右側では下流側となる上方の面の
周縁部に、それぞれ櫛歯状突起６．７を突設している。The valve body 4 has a surface opposite to the valve opening operation direction, that is, in FIGS. 4 and 5, the lower surface is on the upstream side on the left side of the valve stem, and the downstream side is on the right side of the valve stem. Pectine-like protrusions 6 and 7 are respectively provided on the peripheral edge of the upper surface.

この櫛歯状突起６゜７は、キャビテーションの低減を図
るもので、前記従来例で説明したと同様に形成すること
ができる。The comb-like protrusions 6.7 are intended to reduce cavitation, and can be formed in the same manner as described in the conventional example.

そして、本実施例の流量制御弁１においては、前記固定
弁軸３に該弁軸３を径方向に貫通するスリット状の貫通
路８を形成するとともに、弁体４の１次側及び弁体４の
２次側に、該弁体４が小開度の時に前記固定弁軸３の貫
通路８に連通する連通路９，１０をそれぞれ形成してい
る。即ち、第４図に示すように、弁体４が僅かに開かれ
た時に、上記貫通路８と連通路９，１０が合致して１次
側の流体を、弁体１次側の連通路９．固定弁軸３の貫通
路８．弁体２次側の連通路１０を介して弁体２次側に流
出させ、第５図に示すように、弁体４が閉じ状態にある
ときには上記貫通路８と連通路９．１０の位相がずれて
１次側と２次側とを遮断する。In the flow control valve 1 of this embodiment, a slit-shaped through passage 8 passing through the fixed valve shaft 3 in the radial direction is formed in the fixed valve shaft 3, and the primary side of the valve body 4 and the valve body Communication passages 9 and 10 are formed on the secondary side of the valve body 4, respectively, to communicate with the through passage 8 of the fixed valve shaft 3 when the valve body 4 is at a small opening. That is, as shown in FIG. 4, when the valve body 4 is slightly opened, the through passage 8 and the communication passages 9 and 10 match, and the fluid on the primary side is transferred to the communication passage on the primary side of the valve body. 9. Through passage 8 of fixed valve shaft 3. The flow is caused to flow to the secondary side of the valve body through the communication passage 10 on the secondary side of the valve body, and as shown in FIG. deviates, cutting off the primary and secondary sides.

さらに弁体４の２次側には、前記連通路１０から流出す
る流体を弁体２次側の外周部４ａに案内する案内板１１
を設けている。この案内板１１は、板体の両側を同方向
に折曲した形状に形成され、弁体４の２次側表面に、該
案内板１１と弁体２次側表面との間に所定断面積の流体
流路１２を形成するように固定している。Further, on the secondary side of the valve body 4, a guide plate 11 is provided that guides the fluid flowing out from the communication passage 10 to the outer circumference 4a on the secondary side of the valve body.
has been established. This guide plate 11 is formed in a shape in which both sides of the plate body are bent in the same direction, and a predetermined cross-sectional area is formed between the guide plate 11 and the secondary side surface of the valve body 4 on the secondary side surface of the valve body 4. are fixed so as to form a fluid flow path 12.

このように流量制御弁１を形成することにより、弁体４
の小開度時の１次側の流体を、弁体１次側の連通路９．
固定弁軸３の貫通路８．弁体２次側の連通路１０から案
内板１１を介して弁体２次側の外周部４ａに案内するこ
とができる。これにより、弁体外周部４ａと弁箱２との
間から２次側に流出する流体に、該案内板１１からの流
体が加えられるので、該部分で流体が急激に負圧状態に
なることを防止することができ、キャビテーションの発
生を抑制することができる。By forming the flow control valve 1 in this way, the valve body 4
When the opening degree is small, the fluid on the primary side is transferred to the communication path 9 on the primary side of the valve body.
Through passage 8 of fixed valve shaft 3. It can be guided from the communication path 10 on the secondary side of the valve body to the outer peripheral part 4a on the secondary side of the valve body via the guide plate 11. As a result, the fluid from the guide plate 11 is added to the fluid flowing out to the secondary side from between the outer peripheral part 4a of the valve body and the valve body 2, so that the fluid does not suddenly become under negative pressure in this part. can be prevented, and the occurrence of cavitation can be suppressed.

尚、弁体４を全開した場合には、第６図に示すように、
上記貫通路８．連通路９．１０．案内板１１に関係なく
流体が流れる。In addition, when the valve body 4 is fully opened, as shown in FIG.
The above-mentioned through passage 8. Communication path 9.10. The fluid flows regardless of the guide plate 11.

また、上記貫通路８．連通路９，１０．案内板１１等の
形状、及びこれらを通過して流れる流体の量、即ちこれ
らの開口面積は、弁の大きさ、キャビテーション抑制に
必要な流量等により適宜設定することができる。さらに
、弁体外周部４ａ全てに流体を案内導入してもよいが、
キャビテーションの発生の激しい部分にのみ１次側流体
を案内しても、従来に比べてキャビテーションを大幅に
低減することができる。加えて、本実施例に示すように
、弁体４に櫛歯状突起６．７を設けることにより、両者
のｔ０乗効果でキャビテーションの発生をさらに低減さ
せることができる。また、本実施例では、弁軸を上下方
向に設けたが、横方向に設けても同様の作用効果を得る
ことができる。Further, the through passage 8. Communication passages 9, 10. The shape of the guide plate 11 and the like, and the amount of fluid flowing through them, that is, the opening area thereof, can be appropriately set depending on the size of the valve, the flow rate required to suppress cavitation, and the like. Furthermore, although the fluid may be guided and introduced into the entire outer peripheral portion 4a of the valve body,
Even if the primary fluid is guided only to areas where cavitation is most likely to occur, cavitation can be significantly reduced compared to the prior art. In addition, as shown in this embodiment, by providing the comb-like protrusions 6.7 on the valve body 4, the occurrence of cavitation can be further reduced due to the t0 power effect of both. Further, in this embodiment, the valve shaft is provided in the vertical direction, but similar effects can be obtained even if the valve shaft is provided in the horizontal direction.

〔発明の効果〕〔Effect of the invention〕

以上説明したように、本発明の流量制御弁は、固定弁軸
に貫通路を形成するとともに、弁体のｌＪ開度時に該固
定弁軸の貫通路に連通する連通路２弁体の１次側及び２
次側のそれぞれ形成し、弁０の２次側に案内板を設けた
から、弁体の小開度ｕ１にキャビテーションの発生する
慮のある弁体外五部に１次側の流体を導入することがで
き、弁体介周部において流体が急激に負圧状態になるこ
と苓防止し、キャビテーションの発生、及びこれに遷因
する騒音や振動を大幅に低減することができＺAs explained above, the flow control valve of the present invention has a through passage formed in the fixed valve shaft, and two communication passages that communicate with the through passage of the fixed valve shaft when the valve disc is opened at lJ. side and 2
Since a guide plate is provided on the secondary side of valve 0, it is possible to introduce the fluid on the primary side into the outer five parts of the valve body where cavitation may occur at the small opening u1 of the valve body. This prevents the fluid from suddenly becoming a negative pressure state around the valve body, greatly reducing the occurrence of cavitation and the noise and vibration caused by this.

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

図はいずれも本発明の流量制御弁の一実施ｆｌＪ　１示
すもので、第１図は断面正面図、第２図は１沙側から見
た断面側面図、第３図は２次側から見た断面側面図、第
４図は弁体を僅かに開いた状態を示す断面平面図、第５
図は弁体を閉じた状態を写す断面平面図、第６図は弁体
を全開した状態を示す断面平面図である。 ｌ・・・流量制御弁　　２山弁箱　　３・・・固定弁軸
４・・・弁体　　４ａ・・・弁体外周部　　５・・・回
動用弁軸　　６，７・・・櫛歯状突起　　８・・・貫通
路　９゜１０・・・連通路　　１１・・・案内板　　１
２・・・流体流路 同 木　　　戸　　　−彦 同 小 川 眞 、！？２因The figures show one embodiment of the flow control valve of the present invention. Fig. 1 is a sectional front view, Fig. 2 is a sectional side view seen from the 1-sha side, and Fig. 3 is a sectional view seen from the secondary side. Figure 4 is a cross-sectional side view showing the valve body in a slightly opened state;
The figure is a cross-sectional plan view showing the valve body in a closed state, and FIG. 6 is a cross-sectional plan view showing the valve body in a fully open state. l...Flow rate control valve double valve box 3...Fixed valve stem 4...Valve body 4a...Valve body outer circumference 5...Rotating valve stem 6, 7...Comb tooth-like protrusions 8... Penetration path 9゜10... Communication path 11... Guide plate 1
2...Fluid flow path Doki door - Hikodo Ogawa Makoto,! ? 2nd cause

Claims (1)

【特許請求の範囲】[Claims] １、弁箱に設けた固定弁軸に回動可能に支持した弁体を
回動用弁軸により開閉する流量制御弁において、前記固
定弁軸に径方向に貫通する貫通路を形成し、弁体の１次
側及び弁体の２次側に、該弁体が小開度の時に前記弁軸
の貫通路に連通する連通路をそれぞれ形成するとともに
、弁体の２次側に、前記連通路から流出する流体を弁体
２次側の外周部に案内する案内板を設けたことを特徴と
する流量制御弁。1. In a flow control valve in which a valve body rotatably supported by a fixed valve shaft provided in a valve box is opened and closed by a rotating valve shaft, a through passage passing through the fixed valve shaft in a radial direction is formed, and the valve body On the primary side of the valve body and on the secondary side of the valve body, a communication passage is formed, which communicates with the through passage of the valve shaft when the valve body is at a small opening degree, and on the secondary side of the valve body, the communication passage is formed. 1. A flow control valve characterized by being provided with a guide plate for guiding fluid flowing out from the valve body to the outer circumference of the secondary side of the valve body.