JP2004218787A

JP2004218787A - Fixed seal

Info

Publication number: JP2004218787A
Application number: JP2003008926A
Authority: JP
Inventors: Hiroshi Aoshiba; 浩史青柴; Yasushi Kano; 康司加納
Original assignee: Mitsubishi Cable Industries Ltd
Current assignee: Mitsubishi Cable Industries Ltd
Priority date: 2003-01-17
Filing date: 2003-01-17
Publication date: 2004-08-05

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing structure capable of enduring sealing of high pressure fluid. <P>SOLUTION: A fixed seal S forming an opening channel part 3 in the direction of shaft axis by an inner lip part 1 and an outer lip part 2 is provided. This fixed seal S has small projections 20, 20 for sealing low pressure in a small triangular shape in a corner part of a rear surface 5a of a bottom wall part 5, and they come into pressure contact with an outer peripheral face 7 of a shaft and an inner peripheral face 8 of a hole by deforming plastically. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、固定シールに関する。
【０００２】
【従来の技術】
流体として高圧ガスを密封するための適切な密封用シールがほとんど知られておらず、一般的な流体用弁類のシールとして、図７に示すようなゴム製Ｏリング４１が、スプール（軸）４２に一体に形成した凹周溝４３───いわゆる一体溝───に、装着して用いられている。即ち、図７に２点鎖線で示す如く、Ｏリング４１を弾性的に拡径しつつ、基本径端部４４を越えて、スプール（軸）４２の凹周溝４３に装着していた。なお、４５は、ハウジング又はボディ等と呼ばれる弁本体であり、その孔部４５ａの内周面にＯリング４１が接触して、シール（密封）作用をなす。
このような一体溝とする理由は、分割溝構造とした場合、図７の基本径端部４４を別部品として、ネジやボルトやスナップリング等で止着して、組立てる必要があり、かつ、スペース的に大きくなって、弁類の容積が増大する等の問題があるためであった。
【０００３】
【発明が解決しようとする課題】
しかしながら、被密封用流体が例えば７０ＭＰａの高圧気体である場合、ゴム製Ｏリング４１にブリスタや過大な変形を起こす虞があった。
また、金属（メタル）製Ｏリングでは、図７に２点鎖線で示すように拡径（引き伸し）ができず、一体溝構造のスプール（軸）４２へは装着できず、さらに、圧力増減変動に伴って金属製Ｏリングが僅少寸法の往復移動することによって、孔部４５ａ及び金属製Ｏリングの局部的摩耗が著しく、使用に適さない。
【０００４】
そこで、本発明の目的は、上述のような高圧の流体の密封に適用可能であって、構造が簡素でコンパクトであるシールを提供することにある。さらに、前記ブリスタやシールの変形が発生せず、高圧流体の外部漏洩を防止し、寿命が長い固定シールを提供することを他の目的とする。
【０００５】
【課題を解決するための手段】
本発明は、軸外周面に接触する内リップ部と、孔内周面に接触する外リップ部によって、軸心一方向に開口する開口溝部を形成した樹脂製の固定シールに於て、該開口溝部の底壁部の軸心他方向の端部近傍に、装着状態で塑性変形しつつ上記軸外周面・孔内周面に圧接する低圧密封用小突起を、備えている。
【０００６】
また、対向する第１平坦面部と第２平坦面部の間に介装されると共に、該第１平坦面部に接触する第１リップ部と、該第２平坦面部に接触する第２リップ部とによって、ラジアル一方向に開口する開口溝部を形成した樹脂製の固定シールに於て、該開口溝部の底壁部のラジアル他方向の端縁近傍に、装着状態で塑性変形しつつ上記第１平坦面部・第２平坦面部に圧接する低圧密封用小突起を、備えている。
また、上記底壁部の肉厚寸法を、軸心方向寸法の５１％〜８０％に設定し、又は、上記底壁部の肉厚寸法を、ラジアル方向寸法の５１％〜８０％に設定するのが望ましい。
【０００７】
【発明の実施の形態】
以下、図示の実施の形態に基づき本発明を詳説する。
図１と図２は本発明の実施の一形態を示し、図２は自由状態（未装着状態）の固定シールＳの断面図であり、図１は、この自由状態で示す固定シールＳと、装着（使用）箇所との位置関係及び寸法関係を説明する図である。
【０００８】
即ち、このシールＳは、固定（静止）用であって、内リップ部１と外リップ部２を有し、軸心一方向Ａに開口する開口溝部３がこの内外リップ部１，２によって形成され、全体は円環状であって、横断面形状は略Ｕ字型であり、充填材無しのＰＴＦＥとして流体の外部漏洩を防止するのが好ましく、特に、高圧（例えば７０ＭＰａ）用として耐クリープ性に優れている変性ＰＴＦＥが望ましい。このように、本発明のシールＳは、樹脂製の高圧流体用固定部シールである。
【０００９】
そして、この固定シールＳを収納する収納室部４は、固定シールＳの開口溝部３の底壁部５の背面５ａに対応する奥底面６を有すると共に、上記開口溝部３が対応する（開口する）軸心一方向Ａは、開放されている。言い換えると、この収納室部４は、全体が円環状であって、横断面が矩形状の空間であるが、図１の上方向へは、開放されている。
【００１０】
さらに具体的に説明すれば、図１に示した密封構造に於て、弁類のハウジング（ボディ）やタンクやフランジ等の固定部材１１の孔部１２と、この孔部１２内へ挿入された段付１３の軸部材１４によって、上記収納室部４が形成される。軸部材１４は、基本径部１５と、上記段付１３によって縮径した細径軸部１６とを、有し、基本径部１５の外径寸法は孔部１２の内径寸法よりも僅かに小さく設定され、また、段付１３は軸心Ｌと直交する直交面をもって構成され、前述の奥底面６は、この段付１３に相当している。細径軸部１６は、段付１３側から先端───図１の上方端───に向かって、小突条の存在しない同一径で延伸すると共に、最先端部には、先端縮径状のテーパ部１７が形成されている。
固定シールＳは、このテーパ部１７によって、案内誘導されて、スムースに細径軸部１６へ外嵌される。
【００１１】
このようにして、上記収納室部４は、固定部材１１の孔部１２と、この孔部１２へ挿入された段付１３の軸部材１４によって、軸心一方向Ａへ開放するように、形成され、固定シールＳは、スムースにこの収納室部４内へ嵌着可能である。
【００１２】
図１のように、シールＳを装着した状態で、内リップ部１は、細径軸部１６の外周面───軸外周面７───に弾発的に接触し、外リップ部２は、固定部材１１の孔部１２の内周面───孔内周面８───に弾発的に接触する。
【００１３】
図５と図６、及び、図１に於て、軸心一方向Ａの空室側が高圧流体室１８側であって、この高圧流体室１８側の圧力が作用した時、本発明に係るシールＳは、その開口溝部３が拡開するように、内リップ部１は軸外周面７に（図５の矢印Ｆ_０のように）強く圧接し、外リップ部２は孔内周面８に（図５の矢印Ｆ_０のように）強く圧接し、その流体室１８側の圧力Ｐ_０が高まれば、それに伴って、一層強く圧接する自封性シールである。
【００１４】
しかしながら、図６に示す如く、流体室１８の圧力が低下する（低圧となる）と、上述の自封性シールとして、内外リップ部１，２が軸外周面７，孔内周面８に接触する面圧（矢印Ｆ′参照）が極端に低くなって、密封性（シール性）が低下する。そこで、本発明に係る固定シールＳは、図１と図２に示すように、低圧密封用小突起２０，２０を、底壁部５の軸心他方向（矢印Ａと反対方向）の端部近傍５ｂに、具備している。
【００１５】
つまり、図１、及び、図５と図６に於て、装着（使用）状態で、低圧密封用小突起２０，２０は、塑性変形しつつ軸外周面７・孔内周面８に圧接するように、例えば、小三角山型横断面形状として、ラジアル内方及びラジアル外方へ突出形成する。図５中の矢印Ｅ_０と図６中の矢印Ｅ′は、この低圧密封用小突起２０，２０が軸外周面７・孔内周面８に圧接する力を示すが、Ｅ_０やＥ′の大きさは略同一である。
【００１６】
図１と図２の実施の形態では、底壁部５に於て、背面５ａと内周面との角部にラジアル内方向に突出状に１個の低圧密封用小突起２０を配設し、かつ、背面５ａと、外周面との角部にラジアル外方向に突出状に一個の低圧密封用小突起２０を配設している。なお、この低圧密封用小突起２０の断面形状は、図示のような小三角形の他、流体室１８側へ傾いた不等辺小三角形状とするも自由であり、又は、小台形や小半円形（丸山形）等とするも自由である。さらに、この小突起２０を、内径側・外径側に、夫々、複数個ずつ配設して、低圧時の密封性（シール性）を一層向上するも望ましい。
【００１７】
次に、上記底壁部５の（軸心方向に計測した）肉厚寸法Ｔを、シール軸心方向寸法Ｈの５１％〜８０％と、（従来のＵ形シールに比較して）著しく大に設定する。これによって、高圧のガス透過を少なくできる。
【００１８】
なお、図１に示す実施の形態に於て、収納室部４が、軸心一方向Ａに「開放されている」とは、内リップ部１が引掛かる小突条（小突起）が軸外周面７に存在せず、かつ、外リップ部２が引掛かる小突条（小突起）が孔内周面８に存在しないことをいう。言い換えれば、シールＳの開口溝部３が、高圧流体室１８に直接対向している。
【００１９】
次に、図３と図４は本発明の他の実施の形態を示す。図４は自由状態（未装着状態）の固定シールＳの断面図であり、図３は、この自由状態で示す固定シールＳと、装着（使用）箇所との位置関係及び寸法関係を説明するための図である。このシールＳも固定（静止）用であり、同様の材質であって、相対的に対向する第１平坦面部２１と第２平坦面部２２の間に介装される。横断面形状は前述の実施例と同様の略Ｕ字型であるが、開口溝部３の向きがラジアル（内外）一方向Ｒ───図例ではラジアル内方向の場合を示している───に向いている。
【００２０】
第１平坦面部２１に第１リップ部１ａが接触し、第２平坦面部２２に第２リップ部２ａが接触する。開口溝部３は、ラジアル一方向Ｒに開口し、図３ではラジアル内方向を向いており、シールＳの内周側が高圧流体室１８である。
そして、この開口溝部３の底壁部５のラジアル他方向───矢印Ｒと反対方向───の端縁近傍５ｃに、装着状態で塑性変形しつつ第１・第２平坦面部２１，２２に圧接する低圧密封用小突起２０，２０を備えている。
【００２１】
この固定シールＳを収納する収納室部４は、シールＳの底壁部５の背面（外周面）５ａに対応する奥底面６を有すると共に、シールＳの開口溝部３が対応するラジアル一方向Ｒは開放されている。つまり、この収納室部４は、全体が円環状で、横断面が矩形状の空間であり、図３のように内径方向（ラジアル内方向）へは、開放されている。
具体的には、流体機器のハウジング（ボディ）やタンクやフランジ等の固定部材１１ａは、浅い（円形）凹所２３を有し、この浅い凹所２３の底面が上記第１平坦面部２１に相当する。
【００２２】
この固定部材１１ａに対して、図外の固着具や連結具にて、フランジや（他の流体機器の）ケーシング等の蓋部材２４が、固着され、蓋部材２４には凹所２３の内周面２３ａに対向するように嵌合される突部２５が形成されており、この突部２５の先端面が、前記第２平坦面部２２に相当する。そして、ラジアル内方向Ｒに開放されているとは、シールＳが仮に縮径変形したとしても、第１・第２リップ部１ａ，２ａが引掛かる小突起や小突条や壁が存在しないことをいう。
【００２３】
また、図４に於て、底壁部５の肉厚寸法Ｔとシール径方向寸法Ｈ′との間には、０．５１×Ｈ′≦Ｔ≦０．８０×Ｈ′なる関係式が成立するように、寸法を設定する。その理由は前述の図１と図２の実施の形態と同じである。
【００２４】
図３と図４に示した実施の形態に於て、第１リップ部１ａは第１平坦面部２１に、第２リップ部２ａは第２平坦面部２２に、夫々、弾発的に常時接触している。高圧流体室１８側から圧力が作用すれば、開口溝部３が拡開するように、（図５で既に述べたと同様に）第１・第２リップ部１ａ，２ａが開脚せんとして、自封性シールとして、この平坦面用固定シールＳも作用する。
【００２５】
しかしながら、流体室１８の圧力が低下すると、自封性シールとして第１・第２リップ部１ａ，２ａが接触する面圧が極端に低下するので、低圧時の密封性（シール性）が悪化してしまうこととなるが、低圧密封用小突起２０，２０が、第１・第２平坦面部２１，２２に強く圧接しているので、圧力が低下した状態（低圧時）にも、外部漏洩が生じない。
【００２６】
なお、図３と図４では、横断面が小三角形状の小突起２０，２０を、端縁近傍５ｃの角部から両軸心方向に突出させて、装着状態で、塑性変形しつつ第１・第２平坦面部２１，２２に圧接する。この低圧密封用小突起２０の断面形状は、図示の小三角形の他、流体室１８側へ傾いた不等辺小三角形状としたり、小台形や小半円形（丸山形）等としても良く、また、同心円状に、２条以上、配設しても良い。
【００２７】
なお、図示省略するが、図３・図４とは、内外径方向を逆になるようにして、開口溝部３をラジアル外方向（外径方向）に向けて、外周側から高圧が作用するように構成しても良い。その場合、収納室部４は、内径側に奥底面が配設され、かつ、外径側が開放された形状となる。
【００２８】
なお、本発明の各実施の形態に於て、（図示省略したが、）開口溝部３内にバネを設けて、内外リップ部１，２又は第１・第２リップ部１ａ，２ａの弾発力を増加させるようにするも自由である。但し、図１〜図６に示したように、バネを省略すると、部品点数も最少となり、構造が簡素化し、コストダウンを図り得るという利点がある。
【００２９】
また、図１又は図３に示す如く、内外リップ部１，２又は第１・第２リップ部１ａ，２ａが引掛かるような小突起（小突条）が、収納室部４が高圧流体室１８側へ開口する側に、省略されており、軸部材１４又は固定部材１１ａ等の形状及び構造の簡略化を図り得る利点、及び、シールＳの装着（組付）作業が容易となるという利点がある。
【００３０】
【発明の効果】
本発明は上述の構成により次のような著大な効果を奏する。
（請求項１によれば、）高圧作用時は内外リップ部１，２の自封作用によって、密封性（シール性）を発揮し、他方、低圧時には、低圧密封用小突起２０，２０によって確実に密封性（シール性）を維持できる。
しかも、開口溝部３内に装着する金属バネを省略できる場合が多く、部品点数の低減と構造の簡素化と製造容易化を図り得る。
【００３１】
（請求項２によれば、）高圧作用時は第１・第２リップ部１ａ，２ａの自封作用によって、密封性（シール性）を発揮し、他方、低圧時には、低圧密封用小突起２０，２０によって確実に密封性（シール性）を維持できる。
しかも、開口溝部３内に装着する金属バネを省略できる場合が多く、部品点数の低減と構造の簡素化と製造容易化を図り得る。
【００３２】
（請求項３，４によれば、）高圧ガス等の流体の透過を防止できる。
【図面の簡単な説明】
【図１】本発明の実施の一形態を示し構成材の位置関係と寸法関係を説明する図である。
【図２】シールの断面図である。
【図３】他の実施の形態を示し構成材の位置関係と寸法関係を説明する図である。
【図４】シールの断面図である。
【図５】高圧時の作用説明図である。
【図６】低圧時の作用説明図である。
【図７】従来例を示す断面説明図である。
【符号の説明】
１内リップ部
１ａ第１リップ部
２外リップ部
２ａ第２リップ部
３開口溝部
４収納室部
５底壁部
５ａ背面
５ｂ端部近傍
５ｃ端縁近傍
６奥底面
７軸外周面
８孔内周面
２０低圧密封用小突起
２１第１平坦面部
２２第２平坦面部
Ａ軸心一方向
Ｈ，Ｈ′ シール軸心方向寸法
Ｒラジアル一方向
Ｓ固定シール
Ｔ肉厚寸法[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to fixed seals.
[0002]
[Prior art]
An appropriate sealing seal for sealing high-pressure gas as a fluid is hardly known, and a rubber O-ring 41 as shown in FIG. It is mounted and used in a concave circumferential groove 43 {so-called integral groove} formed integrally with 42. That is, as shown by a two-dot chain line in FIG. 7, the O-ring 41 is mounted in the concave peripheral groove 43 of the spool (shaft) 42 beyond the basic diameter end portion 44 while elastically expanding the diameter. Reference numeral 45 denotes a valve body called a housing or a body, and the O-ring 41 comes into contact with the inner peripheral surface of the hole 45a to perform a sealing action.
The reason for using such an integral groove is that, in the case of a divided groove structure, it is necessary to assemble the basic diameter end portion 44 of FIG. 7 as a separate component with a screw, a bolt, a snap ring, or the like, and This is because there is a problem such as an increase in space and an increase in the volume of valves.
[0003]
[Problems to be solved by the invention]
However, when the fluid to be sealed is a high-pressure gas of, for example, 70 MPa, there is a possibility that the rubber O-ring 41 may be blistered or excessively deformed.
In addition, in the case of a metal (metal) O-ring, as shown by a two-dot chain line in FIG. 7, the diameter cannot be expanded (stretched), and the O-ring cannot be mounted on a spool (shaft) 42 having an integrated groove structure. When the metal O-ring reciprocates with a small dimension in accordance with the increase and decrease, local wear of the hole 45a and the metal O-ring is remarkable, which is not suitable for use.
[0004]
Therefore, an object of the present invention is to provide a seal which is applicable to sealing of a high-pressure fluid as described above and has a simple and compact structure. It is another object of the present invention to provide a fixed seal that does not deform the blister or the seal, prevents external leakage of the high-pressure fluid, and has a long life.
[0005]
[Means for Solving the Problems]
The present invention provides a resin-made fixed seal in which an opening groove portion that opens in one direction of an axial center is formed by an inner lip portion that contacts an outer peripheral surface of a shaft and an outer lip portion that contacts an inner peripheral surface of a hole. In the vicinity of the other end of the bottom wall of the groove in the other direction of the axis, a low-pressure sealing small projection which is plastically deformed in the mounted state and is pressed against the outer peripheral surface of the shaft and the inner peripheral surface of the hole is provided.
[0006]
In addition, a first lip portion that is interposed between the opposed first flat surface portion and the second flat surface portion and that contacts the first flat surface portion and a second lip portion that contacts the second flat surface portion. In a resin-made fixed seal formed with an opening groove that opens in one radial direction, the first flat surface portion is plastically deformed in a mounted state near a radial other end of a bottom wall of the opening groove portion. -It has a small projection for low pressure sealing which is pressed against the second flat surface portion.
Also, the thickness of the bottom wall is set to 51% to 80% of the axial dimension, or the thickness of the bottom wall is set to 51% to 80% of the radial dimension. It is desirable.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail based on the illustrated embodiments.
1 and 2 show an embodiment of the present invention. FIG. 2 is a sectional view of a fixed seal S in a free state (unmounted state). FIG. 1 shows a fixed seal S in this free state. It is a figure explaining the positional relationship and dimensional relationship with a mounting (use) location.
[0008]
That is, the seal S is for fixing (stationary), has an inner lip portion 1 and an outer lip portion 2, and an opening groove 3 opening in one direction A of the axial center is formed by the inner and outer lip portions 1, 2. The whole is annular, and the cross-sectional shape is substantially U-shaped, and it is preferable to prevent external leakage of fluid as PTFE without filler, and in particular, creep resistance for high pressure (for example, 70 MPa) It is desirable to use a modified PTFE having excellent properties. Thus, the seal S of the present invention is a fixed part seal for high pressure fluid made of resin.
[0009]
The storage chamber portion 4 for storing the fixed seal S has a back bottom surface 6 corresponding to the back surface 5a of the bottom wall portion 5 of the opening groove portion 3 of the fixed seal S, and the opening groove portion 3 corresponds (opens). ) One axial direction A is open. In other words, the storage chamber part 4 is a space having a whole annular shape and a rectangular cross section, but is open upward in FIG.
[0010]
More specifically, in the sealing structure shown in FIG. 1, a hole 12 of a fixing member 11 such as a housing (body) of a valve, a tank, a flange, or the like, and the hole 12 is inserted into the hole 12. The storage chamber portion 4 is formed by the shaft member 14 having the step 13. The shaft member 14 has a basic diameter portion 15 and a small-diameter shaft portion 16 reduced in diameter by the step 13, and the outer diameter of the basic diameter portion 15 is slightly smaller than the inner diameter of the hole 12. The step 13 is set so as to have an orthogonal plane orthogonal to the axis L, and the above-described inner bottom surface 6 corresponds to the step 13. The small-diameter shaft portion 16 extends from the step 13 side toward the tip {the upper end in FIG. 1} with the same diameter without the small ridges. A tapered portion 17 is formed.
The fixed seal S is guided and guided by the tapered portion 17 and is smoothly fitted to the small-diameter shaft portion 16.
[0011]
In this manner, the storage chamber portion 4 is formed so as to be opened in one axial direction A by the hole portion 12 of the fixing member 11 and the shaft member 14 of the step 13 inserted into the hole portion 12. The fixed seal S can be smoothly fitted into the storage chamber 4.
[0012]
As shown in FIG. 1, with the seal S attached, the inner lip portion 1 resiliently contacts the outer peripheral surface {the shaft outer peripheral surface 7} of the small-diameter shaft portion 16 and the outer lip portion 2. Makes elastic contact with the inner peripheral surface of the hole 12 of the fixing member 11 {the inner peripheral surface 8 of the hole}.
[0013]
In FIGS. 5 and 6, and FIG. 1, the vacant chamber side in one direction A of the axial center is the high-pressure fluid chamber 18 side. S, as the opening groove 3 is expanded, the inner lip portion 1 is pressed (as indicated by the arrow F ₀ in FIG. 5) strongly Jikugaishu surface 7, the outer lip 2 into the hole inner peripheral surface 8 I pressed (as indicated by the arrow F ₀ in FIG. 5) strongly, if Takamare pressure P ₀ of the fluid chamber 18 side, with it, a self-sealing seal to press more strongly.
[0014]
However, as shown in FIG. 6, when the pressure in the fluid chamber 18 decreases (lower pressure), the inner and outer lip portions 1 and 2 contact the shaft outer peripheral surface 7 and the hole inner peripheral surface 8 as the self-sealing seal described above. The surface pressure (see arrow F ') becomes extremely low, and the sealing performance (sealing performance) is reduced. Therefore, in the fixed seal S according to the present invention, as shown in FIGS. 1 and 2, the low-pressure sealing small projections 20 and 20 are attached to the bottom wall 5 at the other end of the axial center (the direction opposite to the arrow A). It is provided in the vicinity 5b.
[0015]
In other words, in FIG. 1 and FIGS. 5 and 6, in the mounted (used) state, the low pressure sealing small projections 20, 20 are pressed against the shaft outer peripheral surface 7 and the hole inner peripheral surface 8 while being plastically deformed. As described above, for example, a small triangular mountain-shaped cross section is formed so as to protrude radially inward and radially outward. Arrow E in arrow E ₀ and in Figure 6 in FIG. 5 ', as shown in the force which the low pressure sealing small projections 20, 20 is pressed against the axial outer peripheral surface 7-hole peripheral surface 8, E ₀ and E' Are approximately the same size.
[0016]
In the embodiment shown in FIGS. 1 and 2, one low-pressure sealing small projection 20 is provided on the bottom wall 5 at the corner between the back surface 5a and the inner peripheral surface so as to project radially inward. In addition, one small-pressure sealing small protrusion 20 is provided at a corner between the back surface 5a and the outer peripheral surface so as to protrude radially outward. The cross-sectional shape of the low-pressure sealing small projection 20 may be a small triangle as shown in the drawing, a small scalene triangle inclined to the fluid chamber 18 side, or a small trapezoid or small semicircle ( (Maruyama shape) etc. are also free. Further, it is desirable that a plurality of the small protrusions 20 are arranged on the inner diameter side and the outer diameter side, respectively, to further improve the sealing property (seal property) at low pressure.
[0017]
Next, the thickness T (measured in the axial direction) of the bottom wall 5 is 51% to 80% of the dimension H in the seal axial direction, which is significantly large (compared to the conventional U-shaped seal). Set to. Thereby, high-pressure gas permeation can be reduced.
[0018]
In the embodiment shown in FIG. 1, the storage chamber portion 4 is “open” in one direction A of the axial center when the small ridge (small projection) on which the inner lip portion 1 is hooked is the axis. It means that the small ridge (small protrusion) that does not exist on the outer peripheral surface 7 and the outer lip portion 2 is hooked on does not exist on the inner peripheral surface 8 of the hole. In other words, the opening groove 3 of the seal S directly faces the high-pressure fluid chamber 18.
[0019]
Next, FIGS. 3 and 4 show another embodiment of the present invention. FIG. 4 is a sectional view of the fixed seal S in a free state (unmounted state), and FIG. 3 is a view for explaining a positional relationship and a dimensional relationship between the fixed seal S shown in the free state and a mounting (use) location. FIG. The seal S is also fixed (stationary), is made of the same material, and is interposed between the first flat surface portion 21 and the second flat surface portion 22 which are relatively opposed to each other. The cross-sectional shape is substantially U-shaped as in the above-described embodiment, but the direction of the opening groove portion 3 is a radial (inside / outside) one direction R (the drawing shows a case where the direction is a radial inward direction). Suitable for
[0020]
The first lip portion 1a contacts the first flat surface portion 21, and the second lip portion 2a contacts the second flat surface portion 22. The opening groove portion 3 opens in one radial direction R, and faces inward in the radial direction in FIG. 3. The inner peripheral side of the seal S is the high-pressure fluid chamber 18.
Then, the first and second flat surface portions 21 and 22 are plastically deformed in the mounted state in the vicinity 5c of the edge of the bottom wall portion 5 of the opening groove portion 3 in the other radial direction {the direction opposite to the arrow R}. The small projections 20 and 20 for low pressure sealing which are pressed into contact with are provided.
[0021]
The storage chamber portion 4 for storing the fixed seal S has a rear bottom surface 6 corresponding to the back surface (outer peripheral surface) 5a of the bottom wall portion 5 of the seal S, and a radial direction R corresponding to the opening groove 3 of the seal S. Is open. That is, the storage chamber portion 4 is a space having a generally annular shape and a rectangular cross section, and is open in the inner diameter direction (radial inward direction) as shown in FIG.
Specifically, the fixing member 11a such as a housing (body), a tank or a flange of the fluid device has a shallow (circular) recess 23, and the bottom surface of the shallow recess 23 corresponds to the first flat surface portion 21. I do.
[0022]
A lid member 24 such as a flange or a casing (of another fluid device) is fixed to the fixing member 11a by a fixing tool or a connecting tool (not shown). A protruding portion 25 is formed so as to be fitted to face the surface 23a, and a distal end surface of the protruding portion 25 corresponds to the second flat surface portion 22. And, being opened in the radial inward direction R means that even if the seal S is reduced in diameter, there are no small projections, small ridges or walls on which the first and second lip portions 1a, 2a are hooked. Say.
[0023]
In FIG. 4, a relational expression of 0.51 × H ′ ≦ T ≦ 0.80 × H ′ is established between the thickness dimension T of the bottom wall 5 and the seal radial dimension H ′. Set the dimensions so that The reason is the same as in the above-described embodiment of FIGS.
[0024]
In the embodiment shown in FIGS. 3 and 4, the first lip portion 1a comes into contact with the first flat surface portion 21 and the second lip portion 2a comes into contact with the second flat surface portion 22 in a resilient manner. ing. When pressure is applied from the high-pressure fluid chamber 18 side, the first and second lip portions 1a and 2a are opened legs so that the opening groove portion 3 expands (similar to that already described with reference to FIG. 5). The flat surface fixed seal S also acts as a seal.
[0025]
However, when the pressure in the fluid chamber 18 decreases, the surface pressure at which the first and second lip portions 1a and 2a come into contact as a self-sealing seal decreases extremely, so that the sealing performance (sealing performance) at low pressure deteriorates. However, since the low-pressure sealing small projections 20 and 20 are strongly pressed against the first and second flat surface portions 21 and 22, external leakage occurs even when the pressure is reduced (at low pressure). Absent.
[0026]
In FIGS. 3 and 4, the small projections 20 having a small triangular cross section project from the corner near the edge 5c in both axial directions, and the first projections 20 and 20 are plastically deformed in the mounted state. Pressing against the second flat surface portions 21 and 22. The cross-sectional shape of the low-pressure sealing small projection 20 may be a small triangle, a trapezoidal shape, a small semicircle (circular mountain shape), or the like, in addition to the small triangle shown in FIG. Two or more strips may be arranged concentrically.
[0027]
Although not shown, the inner and outer radial directions are reversed from those in FIGS. 3 and 4 so that the opening groove 3 is directed radially outward (outer radial direction) so that high pressure acts from the outer peripheral side. May be configured. In this case, the storage chamber portion 4 has a shape in which the inner bottom surface is disposed on the inner diameter side and the outer diameter side is open.
[0028]
In each of the embodiments of the present invention, a spring is provided in the opening groove 3 (not shown) so that the inner and outer lip portions 1 and 2 or the first and second lip portions 1a and 2a are resiliently provided. You are free to increase your power. However, as shown in FIGS. 1 to 6, omitting the spring has the advantage that the number of components is minimized, the structure is simplified, and the cost can be reduced.
[0029]
Also, as shown in FIG. 1 or FIG. 3, small projections (small protrusions) are formed so that the inner and outer lip portions 1 and 2 or the first and second lip portions 1a and 2a can be hooked. It is omitted on the side that opens to the 18 side, and has the advantage that the shape and structure of the shaft member 14 or the fixing member 11a and the like can be simplified, and that the work of mounting (assembling) the seal S becomes easy. There is.
[0030]
【The invention's effect】
The present invention has the following significant effects by the above configuration.
(According to claim 1) At the time of high pressure operation, the self-sealing action of the inner and outer lip portions 1 and 2 exerts a sealing property (sealability). Sealability (sealability) can be maintained.
In addition, in many cases, the metal spring mounted in the opening groove portion 3 can be omitted, so that the number of parts can be reduced, the structure can be simplified, and manufacturing can be facilitated.
[0031]
(According to claim 2) At the time of high pressure, the self-sealing action of the first and second lip portions 1a, 2a exerts a sealing property (sealing property). On the other hand, at the time of low pressure, the low pressure sealing small projections 20, By virtue of 20, the sealing property (sealability) can be reliably maintained.
In addition, in many cases, the metal spring mounted in the opening groove portion 3 can be omitted, so that the number of parts can be reduced, the structure can be simplified, and manufacturing can be facilitated.
[0032]
According to the third and fourth aspects, permeation of a fluid such as a high-pressure gas can be prevented.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an embodiment of the present invention and illustrating a positional relationship and a dimensional relationship of components.
FIG. 2 is a sectional view of a seal.
FIG. 3 is a view showing another embodiment and explaining a positional relationship and a dimensional relationship of components.
FIG. 4 is a sectional view of a seal.
FIG. 5 is an operation explanatory diagram at the time of high pressure.
FIG. 6 is an explanatory diagram of an operation at a low pressure.
FIG. 7 is an explanatory sectional view showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Inner lip part 1a 1st lip part 2 Outer lip part 2a 2nd lip part 3 Opening groove part 4 Storage room part 5 Bottom wall part 5a Back surface 5b Near end part 5c Near end edge 6 Back bottom surface 7 Shaft outer peripheral surface 8 Hole inner periphery Surface 20 Small protrusion 21 for low-pressure sealing First flat surface portion 22 Second flat surface portion A One-way H, H 'seal axis direction dimension R One-way radial direction S Fixed seal T Thickness dimension

Claims

軸外周面（７）に接触する内リップ部（１）と、孔内周面（８）に接触する外リップ部（２）によって、軸心一方向（Ａ）に開口する開口溝部（３）を形成した樹脂製の固定シールに於て、該開口溝部（３）の底壁部（５）の軸心他方向の端部近傍（５ｂ）に、装着状態で塑性変形しつつ上記軸外周面（７）・孔内周面（８）に圧接する低圧密封用小突起（２０）（２０）を、備えていることを特徴とする固定シール。An opening groove (3) opening in one direction (A) of the shaft center by an inner lip (1) contacting the shaft outer peripheral surface (7) and an outer lip (2) contacting the hole inner peripheral surface (8). In the fixed seal made of resin, the outer peripheral surface of the shaft is plastically deformed in the mounted state near the end (5b) of the bottom wall (5) of the opening groove (3) in the other direction of the axis. (7) A fixed seal characterized by comprising small projections (20) and (20) for low pressure sealing which are pressed against the inner peripheral surface (8) of the hole.

対向する第１平坦面部（２１）と第２平坦面部（２２）の間に介装されると共に、該第１平坦面部（２１）に接触する第１リップ部（１ａ）と、該第２平坦面部（２２）に接触する第２リップ部（２ａ）とによって、ラジアル一方向（Ｒ）に開口する開口溝部（３）を形成した樹脂製の固定シールに於て、該開口溝部（３）の底壁部（５）のラジアル他方向の端縁近傍（５ｃ）に、装着状態で塑性変形しつつ上記第１平坦面部（２１）・第２平坦面部（２２）に圧接する低圧密封用小突起（２０）（２０）を、備えていることを特徴とする固定シール。A first lip portion (1a) interposed between the opposed first flat surface portion (21) and the second flat surface portion (22) and in contact with the first flat surface portion (21); In a resin-made fixed seal having an opening groove (3) opened in one radial direction (R) by the second lip portion (2a) in contact with the surface portion (22), the opening groove (3) is formed. A small low-pressure sealing small protrusion that presses against the first flat surface portion (21) and the second flat surface portion (22) while being plastically deformed in a mounted state in the vicinity (5c) of the edge in the radial other direction of the bottom wall portion (5). (20) A fixed seal comprising (20).

上記底壁部（５）の肉厚寸法（Ｔ）を、軸心方向寸法（Ｈ）の５１％〜８０％に設定した請求項１記載の固定シール。The fixed seal according to claim 1, wherein a thickness (T) of the bottom wall (5) is set to 51% to 80% of an axial dimension (H).

上記底壁部（５）の肉厚寸法（Ｔ）を、ラジアル方向寸法（Ｈ′）の５１％〜８０％に設定した請求項２記載の固定シール。3. The fixed seal according to claim 2, wherein the thickness (T) of the bottom wall (5) is set to 51% to 80% of the radial dimension (H ').