Seal ring for plug
The object is to provide a seal ring for a plug, which, when used in a plug cap, can be used regardless of kind of chemical liquid and has no possibility of damaging a seal surface of the plug in tightening the plug cap. The seal ring is placed in the plug cap installed on the plug having a liquid path and/or a gas path, and the seal ring achieves liquid sealing and/or gas sealing of the plug. The seal ring ( 1 ) has on its upper surface an edge seal section ( 17 ), on its inner surface a surface seal section ( 18 ), and on its outer surface a projection section ( 19 ) engaging with a ring engagement section ( 16 a ) formed on the inner surface of the plug cap.
1. A seal ring ( 1 ) for a plug that is disposed inside a plug cap ( 2 ) which covers the plug, wherein the plug is provided with a liquid path and/or a gas path ( 12 ); and that seals fluid from the liquid path of the plug and/or fluid from the gas path ( 12 ) of the plug, comprising:
an edge seal section ( 17 ) in an upper surface of the seal ring ( 1 ), abutting and being compressed and deformed against the plug cap ( 2 ),
a surface seal section ( 18 ) in an inner surface of the seal ring ( 1 ), abutting against a seal surface ( 6 , 6 a ) of the plug, and
a projection section ( 19 ) in an outer surface of the seal ring,
wherein the projection section ( 19 ) is engaged with and deformed against a ring engagement section ( 16 a ) formed in an inner surface of the plug cap ( 2 ).
2. The seal ring ( 1 ) for the plug as set forth in claim 1 , characterized in that: an outer side surface of the seal ring ( 1 ) except the projection section ( 19 ) thereof is spaced apart from or brought into slidable contact with an inner side surface of the plug cap ( 2 ).
3. The seal ring ( 1 ) for the plug as set forth in claim 1 , characterized in that: the edge seal section ( 17 ) is brought into line-contact with an edge seal surface of the ring engagement section ( 16 ); the surface seal section ( 18 ) forms a curved surface in cross section, and is brought into area contact with an outer peripheral surface of the plug to realize strain sealing.
4. The seal ring ( 1 ) for the plug as set forth in claim 3 , characterized in that: a single or a plurality of edge seal sections ( 21 ) is provided in a lower side of the surface seal section ( 18 ).
5. A seal ring ( 1 ) for a plug that is disposed inside a plug cap ( 2 ) which covers the plug, wherein the plug is provided with a liquid path and/or a gas path ( 12 ); and that the seal ring ( 1 ) seals fluid from the liquid path of the plug and/or fluid from the gas path ( 12 ) of the plug, comprising:
a surface seal section( 18 ) in an inner side surface of the seal ring ( 1 ), abutting against a seal surface ( 6 , 6 a ) of the plug, and
a projection section ( 19 ) in an outer side surface of the seal ring,
wherein the projection section is engaged with and deformed against a ring engagement section ( 16 a ) formed in an inner surface of the plug cap ( 2 ).
6. The seal ring ( 1 ) for the plug as set forth in claim 5 , wherein the seal ring ( 1 ) is provided with an edge section ( 17 ) in its upper surface.
7. The seal ring ( 1 ) for the plug as set forth in claim 5 , characterized in that an outer side surface of the seal ring ( 1 ) except the projection section ( 19 ) thereof is spaced apart from or brought into slidable contact with an inner side surface of the plug cap ( 2 ).
8. A seal ring ( 1 ) for a plug that is disposed inside a plug cap ( 2 ) which covers the plug, the plug being provided with a gas path ( 12 ), wherein the seal ring ( 1 ) seals fluid from the gas path ( 12 ) of the plug, comprising:
a first edge section ( 31 ), having at least one lip which abuts against an edge seal ( 16 ) surface of a ring engagement ( 15 ) section formed inside the plug cap ( 2 ); and
a second edge section ( 32 ), which abuts against a seal surface ( 6 c ) of the plug,
wherein the second section ( 32 ) has a larger number of lips than the first section ( 31 ).
9. The seal ring ( 1 ) for a plug as set forth in claim 8 wherein the second edge section ( 32 ) has a plurality of lips which abut against the seal surface ( 6 c ) of the plug, and the second section ( 32 ) has a larger number of lips than the first section ( 31 ).