| 摘要 |
A valve device includes: a main valve element arranged so as to divide a valve element space of a housing into a first pressure chamber and a second pressure chamber; and a pilot valve element arranged in the second pressure chamber. A first pilot passage including a first restrictor extends from an outside of the housing or the primary passage to the second pressure chamber, and a second pilot passage including a second restrictor is formed at the main valve element. The pilot valve element is biased by a biasing member to close an upstream end of the second pilot passage. When electric power is supplied to a drive unit, the pilot valve element opens the upstream end of the second pilot passage. An excess flow prevention valve including a third restrictor is provided at the second pilot passage so as to be located downstream of the second restrictor. |
