Electromagnetically operated valve assembly

Claim 1

An electromagnetically operated valve assembly comprising a flow control valve section and an operating device section for said flow control valve section, said flow control valve section comprising passage-defining means defining a passage through which fluid is passed, a valve seat located in said passage and dividing said passage into upstream and downstream portions, and a valve disposed in said passage movable relative to said valve seat for engagement with and disengagement from said valve seat, said operating device section comprising a coil having a core, said coil being alternatively energized and de-energized for causing magnetization and demagnetization of said core, respectively, a movable member movable toward and away from said core in response to energization and deenergization of said coil, respectively, a shield, both surfaces of said shield being flat at all times, said shield being fixedly secured at one of said surfaces thereof to an end surface of said movable member, said shield being made of a nonmagnetic metal having a great hardness greater than Vickers Hardness 200, said shield being engageable with and disengagement from said core when said movable member is moved toward and away from said core, respectively, biasing means for urging said movable member away from said core, said movable member being so operatively connected to said valve that said valve is engaged with said valve seat for blocking communication between said upstream and downstream portions when moved toward said core, a flexible diaphragm defining a pressure chamber in said passage downstream of said valve seat, said movable member being so operatively connected to said diaphragm that said diaphragm is moved into a position to increase the volume of said pressure chamber sucking in fluid thereinto from said upstream portion when said movable member is moved toward said core and into a position to reduce the volume of said pressure chamber for forcing out fluid from said pressure chamber to said passage downstream of said pressure chamber when said movable member is moved away from said core.