Temperature-controlled PCV valve

A positive crankcase ventilation valve for use with a vehicle engine having a throttle valve movable between an idle position and a wide-open position, the valve comprising

• a shell including a valve housing formed to include an interior region, an inlet arranged to open into the interior region and adapted to be coupled to a crankcase of a vehicle, and an outlet arranged to open into the interior region and adapted to be coupled to an intake manifold of the vehicle, the shell further including a partition wall located in the interior region in fixed relation to the valve housing to partition the interior region to define an inlet chamber located between the inlet and the partition wall to communicate with the inlet and an outlet chamber located between the outlet and the partition wall to communicate with the outlet, the partition wall including an interior border edge defining an orifice and providing a first flow-metering surface bordering the orifice,
• a flow controller elevator including a platform stop located in the inlet chamber in a fixed position below the partition wall, a movable support platform mounted for up-and-down movement in the inlet chamber in a space provided between the partition wall and the platform stop, and a platform mover located in the inlet chamber and arranged normally to yieldably urge the movable support platform downwardly in the space to a lowered wide-open throttle position engaging the platform stop, the movable support platform being configured to move upwardly in the space toward the partition wall against a downward biasing force applied by the platform mover to assume a raised engine-idle position above the platform stop upon exposure of a top side of the movable support platform facing toward the partition wall to a vacuum in excess of a predetermined minimum vacuum during idling of an engine associated with the valve, and
• a flow controller carried on the movable support platform as the movable support platform moves in the valve housing between the lowered wide-open throttle position and the raised engine-idle position, the flow controller including a flow restrictor extending into the orifice and providing a second flow-metering surface which cooperates with the first flow-metering surface to define a variable flow-metering channel therebetween during movement of the movable support platform between the lowered wide-open throttle position and the raised engine-idle position, the second flow-metering surface being moved in relation to the first flow-metering surface in response to movement of the flow restrictor in the orifice relative to the partition wall to vary the size of the flow-metering channel, the flow controller further including temperature-responsive means for moving the flow restrictor in the orifice and relative to the movable support platform to vary the size of flow-metering channel from a retracted low-temperature position located a first distance away from the movable support platform when fumes extant in the inlet chamber have a first temperature associated with a cold-start condition of the engine to an extended high-temperature position located a greater second distance away from the movable support platform when fumes extant in the inlet chamber have at least a second temperature that is greater than the first temperature and is associated with a hot-run condition of the engine.