JPH1047498A - Shaft seal device for butterfly valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the sealing effect of a shaft seal device for a butterfly valve by varying the hardness of its elastic member for sealing a butterfly valve in plural layers. SOLUTION: A valve element 2 is rotatably arranged in a valve casing 1 through a valve stem 3, and a hub seal ring 5 comprising a ring body 5A and an elastic member 5B fitted over the outer periphery and end face of the ring body 5A is fitted around the valve stem 3 as well as inserted into a bearing cylinder 1a of the valve casing 1. With the ring body 5A being pressured by a pressure cylinder 6 pressed into the bearing cylinder 1a, the elastic member 5B is brought into press contact with the inner periphery of the bearing cylinder 1a and the outer periphery of the valve body 2. The elastic member 5B comprises an end-face layer 5a extending along the end face of the ring body 5A, an intermediate layer 5b extending along the end-face layer 5a, and an outer-peripheral layer 5c extending along the outer periphery of the ring body 5A perpendicularly to the intermediate layer 5b, and the hardness of the intermediate layer 5b is set smaller than that of the end-face layer 5a.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、シール性を向上さ
せたバタフライ弁の軸封装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butterfly valve shaft sealing device having improved sealing performance.

【０００２】[0002]

【従来の技術】従来、バタフライ弁の一例として実公昭
５５−５０４３９号公報に記載のものがある。これは、
図３に示すように、弁箱１内に弁体２が弁棒３を介して
回転可能に配設され、弁箱１の内面に、弁体２の外周縁
に接する左右一対の周縁シール部４と、弁棒３に外嵌し
て弁箱１の軸受筒１ａ内に挿入されるハブシールリング
５とが設けられている。2. Description of the Related Art A conventional butterfly valve is disclosed in Japanese Utility Model Publication No. 55-50439. this is,
As shown in FIG. 3, a valve body 2 is rotatably disposed in a valve box 1 via a valve rod 3, and a pair of left and right peripheral seal portions in contact with the outer peripheral edge of the valve body 2 are provided on the inner surface of the valve box 1. 4 and a hub seal ring 5 which is fitted to the valve rod 3 and inserted into the bearing tube 1 a of the valve box 1.

【０００３】前記ハブシールリング５は、図４に示すよ
うに、金属からなるリング本体５Ａと、該リング本体５
Ａの外周面から端面にかけて取り付けられたゴムなどか
らなる弾性部材５Ｂとからなり、前記軸受筒１ａ内に押
し込んだ押さえ筒６でリング本体５Ａを押圧することに
より、弾性部材５Ｂが軸受筒１ａの内周面及び弁体２の
外周面に圧接されるようになっている。As shown in FIG. 4, the hub seal ring 5 includes a ring main body 5A made of metal and a ring main body 5A.
A is made of an elastic member 5B made of rubber or the like attached from the outer peripheral surface to the end surface of A, and by pressing the ring body 5A with the holding cylinder 6 pushed into the bearing cylinder 1a, the elastic member 5B The inner peripheral surface and the outer peripheral surface of the valve body 2 are pressed against each other.

【０００４】[0004]

【発明が解決しようとする課題】上記従来の構成では、
弾性部材５Ｂがゴムなどの単一部材からなり、その弾性
部材５Ｂの全体が同一硬度であるため、押さえ筒６で押
圧することにより、その弾性部材５Ｂが全体的に弾性変
形される。従って、高圧で大口径のバタフライ弁の場合
には、軸受筒１ａの内周面に対する弾性部材５Ｂの圧接
力が不足して、シール性が低下し、ハブシールリング５
と軸受筒１ａとの間から流体が漏洩する虞れがある。In the above-mentioned conventional configuration,
Since the elastic member 5B is formed of a single member such as rubber, and the entire elastic member 5B has the same hardness, the elastic member 5B is entirely elastically deformed by being pressed by the holding cylinder 6. Accordingly, in the case of a high pressure, large diameter butterfly valve, the pressure contact force of the elastic member 5B against the inner peripheral surface of the bearing cylinder 1a is insufficient, and the sealing performance is reduced, and the hub seal ring 5
There is a possibility that fluid may leak from between the bearing cylinder 1a.

【０００５】本発明は、上記問題点に鑑み、シール性を
向上させたバタフライ弁の軸封装置を提供することを目
的としている。SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a butterfly valve shaft sealing device having improved sealing performance.

【０００６】[0006]

【課題を解決するための手段】上記目的を達成するた
め、請求項１記載の発明は、弁箱内に弁体が弁棒を介し
て回転可能に配設され、前記弁棒に外嵌して前記弁箱の
軸受筒内に挿入されるハブシールリングが設けられ、該
ハブシールリングは、リング本体と、該リング本体の外
周面から端面にかけて取り付けられた弾性部材とからな
り、前記軸受筒内に押し込んだ押さえ筒で前記リング本
体を押圧することにより、前記弾性部材が軸受筒の内周
面及び弁体の外周面に圧接されるように構成したバタフ
ライ弁の軸封装置において、前記弾性部材がハブシール
リングの軸心方向に沿って複数層に分かれ、その各層の
硬度を異ならせたことを特徴としている。In order to achieve the above object, according to the first aspect of the present invention, a valve element is rotatably disposed in a valve box via a valve rod, and is externally fitted to the valve rod. A hub seal ring that is inserted into a bearing cylinder of the valve box, the hub seal ring includes a ring main body, and an elastic member attached from an outer peripheral surface to an end surface of the ring main body. In the butterfly valve shaft sealing device, the elastic member is configured to be pressed against the inner peripheral surface of the bearing cylinder and the outer peripheral surface of the valve body by pressing the ring main body with the holding cylinder pushed in. The member is divided into a plurality of layers along the axial direction of the hub seal ring, and the hardness of each layer is different.

【０００７】上記構成によれば、軸受筒内に押さえ筒を
押し込むことにより、ハブシールリングの弾性部材が押
圧されて、該弾性部材の硬度の小さい層が大きく弾性変
形して外側に押し出され、その層の出代が大きくなって
軸受筒の内周面に強く圧接される。従って、高圧で大口
径のバタフライ弁の場合でも、軸受筒の内周面に弾性部
材を確実に圧接させて、シール性を高め、ハブシールリ
ングと軸受筒との間から流体が漏洩しないようにするこ
とができる。According to the above construction, by pushing the holding cylinder into the bearing cylinder, the elastic member of the hub seal ring is pressed, and the layer of the elastic member having a small hardness is largely elastically deformed and pushed outward. The protrusion of the layer increases, and the layer is strongly pressed against the inner peripheral surface of the bearing cylinder. Therefore, even in the case of a high-pressure, large-diameter butterfly valve, the elastic member is securely pressed against the inner peripheral surface of the bearing cylinder to enhance the sealing performance and prevent the fluid from leaking from between the hub seal ring and the bearing cylinder. can do.

【０００８】請求項２記載の発明は、請求項１記載の発
明において、前記弾性部材が、リング本体の端面に沿っ
て延びる端面層と、該端面層に沿って延びる中間層と、
該中間層から直角にリング本体の外周面に沿って延びる
外周層とからなり、前記中間層の硬度を端面層の硬度よ
りも小さく設定したことを特徴としている。According to a second aspect of the present invention, in the first aspect of the present invention, the elastic member includes an end surface layer extending along an end surface of the ring body, an intermediate layer extending along the end surface layer,
An outer peripheral layer extending at right angles from the intermediate layer along the outer peripheral surface of the ring main body, wherein the hardness of the intermediate layer is set smaller than the hardness of the end face layer.

【０００９】上記構成によれば、弾性部材が押圧される
ことにより、硬度の小さい中間層が大きく弾性変形して
外側に押し出され、その出代が大きくなるから、その弾
性部材の中間層を軸受筒の内周面に強く圧接させて、シ
ール性を確実に維持することができる。また、端面層の
変形量が中間層の変形量よりも小さいため、その耐久性
を向上させることができる。According to the above structure, when the elastic member is pressed, the intermediate layer having a small hardness is largely elastically deformed and extruded outward, so that the margin of the elastic member is increased. By strongly pressing against the inner peripheral surface of the cylinder, the sealing performance can be reliably maintained. Further, since the amount of deformation of the end face layer is smaller than the amount of deformation of the intermediate layer, the durability can be improved.

【００１０】[0010]

【発明の実施の形態】以下、本発明の実施の形態を図面
に基づいて説明する。図１及び図２は本発明の実施の一
形態であるバタフライ弁の軸封装置を示すものであっ
て、ハブシールリング５の弾性部材５Ｂが、リング本体
５Ａの端面に沿って延びる端面層５ａと、該端面層５ａ
に沿って延びる中間層５ｂと、該中間層５ｂから直角に
リング本体５Ａの外周面に沿って延びる外周層５ｃとか
らなっている。上記以外の構成は図３及び図４に示す従
来例とほぼ同じであるから、同一部分に同一符号を付し
てその説明を省略する。Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a shaft sealing device for a butterfly valve according to an embodiment of the present invention, in which an elastic member 5B of a hub seal ring 5 has an end surface layer 5a extending along an end surface of a ring main body 5A. And the end face layer 5a
And an outer peripheral layer 5c extending along the outer peripheral surface of the ring body 5A at right angles from the intermediate layer 5b. Since the configuration other than the above is substantially the same as the conventional example shown in FIGS. 3 and 4, the same portions are denoted by the same reference numerals and description thereof will be omitted.

【００１１】前記中間層５ｂと外周層５ｃとは略Ｌ字状
に一体形成され、中間層５ｂと端面層５ａとは一体接合
されている。また、中間層５ｂ及び外周層５ｃの硬度
〔例えばＨｓ＝４０〜５０〕を端面層５ａの硬度〔例え
ばＨｓ＝６０〜７０〕よりも小さく設定して、弾性部材
５Ｂが押圧されたときに、中間層５ｂが大きく弾性変形
されるようにしている。The intermediate layer 5b and the outer peripheral layer 5c are integrally formed in a substantially L-shape, and the intermediate layer 5b and the end face layer 5a are integrally joined. Also, when the hardness (for example, Hs = 40 to 50) of the intermediate layer 5b and the outer peripheral layer 5c is set smaller than the hardness (for example, Hs = 60 to 70) of the end face layer 5a, when the elastic member 5B is pressed, The mid layer 5b is largely elastically deformed.

【００１２】上記構成において、軸受筒１ａ内に押さえ
筒６を押し込むことにより、ハブシールリング５の弾性
部材５Ｂが押圧されると、該弾性部材５Ｂの端面層５ａ
が弁体２の外周面に圧接されて、ハブシールリング５と
弁体２との間のシール性を維持することができ、また、
端面層５ａの変形量が中間層５ｂの変形量よりも小さい
ため、その端面層の耐久性を向上させることができる。In the above structure, when the elastic member 5B of the hub seal ring 5 is pressed by pushing the holding cylinder 6 into the bearing cylinder 1a, the end face layer 5a of the elastic member 5B is pressed.
Is pressed against the outer peripheral surface of the valve body 2 to maintain the sealing property between the hub seal ring 5 and the valve body 2.
Since the amount of deformation of the end surface layer 5a is smaller than the amount of deformation of the intermediate layer 5b, the durability of the end surface layer can be improved.

【００１３】更に、弾性部材５Ｂの中間層５ｂがリング
本体５Ａと端面層５ａとで挟まれて圧縮されることによ
り、図２の左側に示す面圧分布図ａから明らかなよう
に、中間層５ｂが大きく弾性変形されて外側に押し出さ
れ、その出代が大きくなって軸受筒１ａの内周面に強く
圧接され、ハブシールリング５と軸受筒１ａとの間のシ
ール性を確実に維持することができる。Further, when the intermediate layer 5b of the elastic member 5B is sandwiched between the ring main body 5A and the end face layer 5a and compressed, as is apparent from the surface pressure distribution diagram a shown on the left side of FIG. 5b is largely elastically deformed and is pushed outwardly, and its protrusion is increased to be strongly pressed against the inner peripheral surface of the bearing cylinder 1a, thereby reliably maintaining the sealing property between the hub seal ring 5 and the bearing cylinder 1a. be able to.

【００１４】上記実施の形態では、端面層５ａと中間層
５ｂとの２層構造にしているが、これに限定されるわけ
ではなく、高圧で大口径のバタフライ弁で、図２に示す
ように、端面層５ａ及び中間層５ｂの高さＨが大きくな
る場合には（例えば３０ｍｍ以上）、３層構造以上と
し、その各層の硬度を異ならせることにより、シール性
を一層向上させることができる。In the above embodiment, a two-layer structure of the end face layer 5a and the intermediate layer 5b is used. However, the present invention is not limited to this, and a high-pressure, large-diameter butterfly valve as shown in FIG. When the height H of the end face layer 5a and the intermediate layer 5b is large (for example, 30 mm or more), the sealability can be further improved by making the structure of three layers or more and varying the hardness of each layer.

【００１５】[0015]

【発明の効果】請求項１記載の発明によれば、軸受筒内
に押さえ筒を押し込むことにより、ハブシールリングの
弾性部材が押圧されて、該弾性部材の硬度の小さい層が
大きく弾性変形して外側に押し出され、その層の出代が
大きくなって軸受筒の内周面に強く圧接される。従っ
て、高圧で大口径のバタフライ弁の場合でも、軸受筒の
内周面に弾性部材を確実に圧接させて、シール性を高
め、ハブシールリングと軸受筒との間から流体が漏洩し
ないようにすることができる。According to the first aspect of the present invention, when the pressing cylinder is pushed into the bearing cylinder, the elastic member of the hub seal ring is pressed, and the layer having a small hardness of the elastic member is largely elastically deformed. The outer layer is extruded outward, and the margin of the layer increases, and the layer is strongly pressed against the inner peripheral surface of the bearing cylinder. Therefore, even in the case of a high-pressure, large-diameter butterfly valve, the elastic member is securely pressed against the inner peripheral surface of the bearing cylinder to enhance the sealing performance and prevent the fluid from leaking from between the hub seal ring and the bearing cylinder. can do.

【００１６】請求項２記載の発明によれば、弾性部材が
押圧されることにより、硬度の小さい中間層が大きく弾
性変形して外側に押し出され、その出代が大きくなるか
ら、その弾性部材の中間層を軸受筒の内周面に強く圧接
させて、シール性を確実に維持することができる。ま
た、端面層の変形量が中間層の変形量よりも小さいた
め、その端面層の耐久性を向上させることができる。According to the second aspect of the present invention, when the elastic member is pressed, the intermediate layer having low hardness is largely elastically deformed and extruded outward, so that the margin of the elastic member is increased. The intermediate layer is strongly pressed against the inner peripheral surface of the bearing cylinder, so that the sealing property can be reliably maintained. Further, since the amount of deformation of the end surface layer is smaller than the amount of deformation of the intermediate layer, the durability of the end surface layer can be improved.

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

【図１】本発明の実施の一形態であるバタフライ弁の軸
封装置の縦断面図である。FIG. 1 is a longitudinal sectional view of a shaft sealing device for a butterfly valve according to an embodiment of the present invention.

【図２】同ハブシールリングの縦断面図である。FIG. 2 is a longitudinal sectional view of the hub seal ring.

【図３】従来例を示す縦断面図である。FIG. 3 is a longitudinal sectional view showing a conventional example.

【図４】同軸封装置の縦断面図である。FIG. 4 is a longitudinal sectional view of the coaxial sealing device.

【符号の説明】[Explanation of symbols]

１ 弁箱 １ａ 軸受筒 ２ 弁体 ３ 弁棒 ５ ハブシールリング ５Ａ リング本体 ５Ｂ 弾性部材 ５ａ 端面層 ５ｂ 中間層 ５ｃ 外周層 ６ 押さえ筒 DESCRIPTION OF SYMBOLS 1 Valve box 1a Bearing cylinder 2 Valve body 3 Valve stem 5 Hub seal ring 5A Ring body 5B Elastic member 5a End face layer 5b Intermediate layer 5c Outer peripheral layer 6 Holding cylinder

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 弁箱内に弁体が弁棒を介して回転可能に
配設され、前記弁棒に外嵌して前記弁箱の軸受筒内に挿
入されるハブシールリングが設けられ、該ハブシールリ
ングは、リング本体と、該リング本体の外周面から端面
にかけて取り付けられた弾性部材とからなり、前記軸受
筒内に押し込んだ押さえ筒で前記リング本体を押圧する
ことにより、前記弾性部材が軸受筒の内周面及び弁体の
外周面に圧接されるように構成したバタフライ弁の軸封
装置において、前記弾性部材がハブシールリングの軸心
方向に沿って複数層に分かれ、その各層の硬度を異なら
せたことを特徴とするバタフライ弁の軸封装置。A hub seal ring is provided in a valve box so as to be rotatable via a valve rod, and is fitted to the valve rod and inserted into a bearing cylinder of the valve box. The hub seal ring includes a ring main body, and an elastic member attached from the outer peripheral surface to the end surface of the ring main body. The elastic member is pressed by pressing the ring main body with a holding cylinder pushed into the bearing cylinder. The elastic member is divided into a plurality of layers along the axial direction of the hub seal ring in the shaft sealing device of the butterfly valve configured so that the elastic member is pressed against the inner peripheral surface of the bearing cylinder and the outer peripheral surface of the valve body. A shaft sealing device for a butterfly valve, characterized by having different hardnesses. 【請求項２】 前記弾性部材が、リング本体の端面に沿
って延びる端面層と、該端面層に沿って延びる中間層
と、該中間層から直角にリング本体の外周面に沿って延
びる外周層とからなり、前記中間層の硬度を端面層の硬
度よりも小さく設定したことを特徴とする請求項１記載
のバタフライ弁の軸封装置。2. An end face layer extending along an end face of the ring main body, an intermediate layer extending along the end face layer, and an outer peripheral layer extending perpendicularly from the intermediate layer along the outer peripheral face of the ring main body. 2. The shaft sealing device for a butterfly valve according to claim 1, wherein the hardness of the intermediate layer is set smaller than the hardness of the end face layer.