Patent ID: 7562675

Claim:
A valve device comprising: a housing in which a valve path is defined; plural valve bodies displaceably held in said housing for opening and closing said valve path; and a single common seat block provided for said plural valve bodies and fixed to said housing for said plural valve bodies to be pressed thereon, said seat block having seat portions each comprising a soft material for said valve bodies to be pressed on respective of said seat portions, wherein: said seat block comprises a base comprising a hard material, a first seat-forming member fitted on said base to form a first one of said seat portions, and a second seat-forming member coupled to said base to form a second one of said seat portions, each of the first and second seat-forming members comprising the soft material; said base is fixed to said housing; said second seat-forming member is held between said base and said housing; and said base and said second seat-forming member provide sealing when a closed loop sharp ridge formed on said base is brought into contact with said second seat-forming member.