Patent attributes
A valve includes a valve mechanism capable of switching a communication state between a first port and a second port of a body. A diaphragm is held between a valve plug and a holder member, at a central portion of the valve mechanism. An outer marginal portion of the diaphragm is held between the body and the bonnet. A pilot channel through which a communication chamber in the body and a pilot chamber in the bonnet communicate with each other is formed in the valve plug. A first hole communicating with the pilot channel is formed at a central portion of the diaphragm. Pressurized fluid in the communication chamber flows into the pilot chamber through the pilot channel and the first hole to thereby bias the valve plug toward a valve seat, by the pressure of the pressurized fluid in combination with an elastic force of a spring.
