Check valve

A check valve comprising:

• a casing having a flow path formed therein and a valve seat formed at an intermediate portion of said flow path;
• a valving element disposed in said flow path, said valving element being movable in the flow path to selectively seat on and unseat from said valve seat,
• an urging member that urges said valving element toward said valve seat,
• said check valve further comprising;
• a substantially circular cylindrical valving element support fixedly disposed centrally in said flow path downstream of the valve seat, said valving element support movably supporting said valving element, and
• an intermediate flow path which is annular in section formed between an outer periphery of said valving element support and an inner periphery of said casing,
• wherein said valving element comprises:
• a head portion comprising a top portion for seating on and unseating from said valve seat, said head portion also comprising a column portion extending in the downstream direction,
• wherein said valving element support comprises;
• a recess comprising a mouth at an upstream portion of said valving element support which movably receives said column portion of said valving element, said recess comprising an inside portion extending behind at least a portion of said head portion of the valving element;
• wherein said intermediate flow path comprises a narrow flow path portion extending from said mouth of said recess toward the downstream side, said narrow flow path portion being narrower than the rest of said intermediate flow path in the flow path area which is downstream of said narrow flow path portion,
• said check valve further comprising;
• a communicating passage formed between an inner periphery of said recess and an outer periphery of said column portion of the valving element, said communicating passage extending from said mouth of said recess and connecting said narrow flow path portion of the intermediate flow path to said inside portion of the recess.