To provide a valve of simple configuration in which the risk of damaging of a resilient member is lessened.

A valve includes a seat 22 confronting a pressure chamber and equipped with a communication hole 22a as fluid passage and a valve element 21 which is installed in the pressure chamber and shuts the communication between the hole 22ac and pressure chamber when it contacts with the seat 22, wherein the valve seat 22 has a ring-shaped surface 22d and a ring- shaped projection 22ba while the valve element 21 is furnished with the first abutting part 21aa and the second abutting part 22ba, wherein the periphery of the first abutting part 21aa is a certain distance A separated from the inside surface of the ring-shaped projection 22ba.