Isolation valve with fast depressurization for high-pressure fuel tank

An isolation valve, comprising:

• a flow restrictor disposed in a passage having non-parallel sides, the flow restrictor having an orifice;
• a flow restrictor spring that applies a biasing force on the flow restrictor to bias the flow restrictor to an open position;
• and
• a solenoid assembly, including:
• a coil;
• and
• an armature that is moveable between (i) an extended position that overcomes the biasing force of the restrictor spring to move the flow restrictor to a closed position and to close the second orifice, and (ii) a retracted position to open the orifice,
• wherein when the coil is energized, the armature moves to the retracted position to allow vapor to flow through the orifice at least until the biasing force of the flow restrictor spring overcomes a vapor pressure;
• and, the open position of the flow restrictor allows vapor to flow through a space between the flow restrictor and the passage;
• wherein a first side of the non-parallel sides includes a plurality of steps.

An isolation valve, comprising:

• a body including a passage having non-parallel sides;
• a flow restrictor disposed in the passage, the flow restrictor including:
• an orifice;
• an open position in which the flow restrictor allows vapor flow in a space between the flow restrictor and the passage;
• and
• a closed position in which the flow restrictor prevents vapor flow between the flow restrictor and the passage;
• and
• an armature movable between (i) an extended position in which the armature prevents vapor flow through the orifice, and (ii) a retracted position, in which the armature allows vapor flow through the orifice;
• wherein the non-parallel sides include a stepped side having at least two steps.

A method of operating an isolation valve, the method comprising:

• providing an isolation valve body including a passage having non-parallel sides;
• providing an flow restrictor in the passage, the flow restrictor including:
• an orifice;
• and
• a piston movable between (i) an open position in which the flow restrictor allows vapor flow in a space between the flow restrictor and the passage, and (ii) a closed position in which the flow restrictor prevents vapor flow between the flow restrictor and the passage;
• and
• providing an armature movable between (i) an extended position in which the armature prevents vapor flow through the orifice, and (ii) a retracted position, in which the armature allows vapor flow through the orifice;
• moving the armature to the retracted position to allow vapor to flow through the orifice;
• reducing a vapor pressure via vapor flowing through the orifice;
• and
• moving the piston gradually from the closed position toward the open position;
• wherein the configuration of the non-parallel sides includes the passage including at least three steps.