Abstract: An electrically operated EGR valve has a pintle for opening and closing the valve. The pintle is actuated by an linear actuator to open and close two ports which are connected to the outlet of the valve. The pintle has a frustoconical surface which mates with the two ports. The input passageway to the EGR valve is in fluid communication with both sides of the pintle which are the sides taken in direction of the movement of the linear actuator. The pintle being pressure-balanced when the electrically operated linear actuator attempts to move the pintle to either further open or further close the ports, the pintle is more responsive without increasing the size of the actuator.

Abstract: The evaporative emission control system for an internal combustion engine purges the vapor collection canister to the intake manifold through a purge regulator controlled by the engine ECU. The purge regulator comprises a diaphragm valve and an electronic vacuum regulator. The purge regulator functions to allow a purge flow rate correlated with a control signal from the engine ECU and manifold vacuum, to maintain the purge flow rate substantially constant in response to certain changes in the magnitude of manifold vacuum, and to re-adjust the purge flow rate in correlation with changes in the control signal from the engine ECU. The diaphragm valve comprises a tapered valve element that progressively reduces the flow restriction as the valve element is increasingly opened.

Abstract: The valve shaft passes through a journal bearing in the wall of the valve body to an actuating lever attached to the shaft on the outside of the valve body. This journal bearing is sealed by an arrangement of several parts to prevent escape of exhaust gases. These parts include a bellows and ceramic thrust washers. By making the valve shaft axis non-perpendicularly intersecting the axis of the valve body wall, the entire circumference of the valve blade can be sealed to the valve body wall when the valve is closed.

Abstract: An irregularity that might otherwise be present in the flow characteristic of the system is cured by damping the motion of the armature of the CPS valve in two ways. One way comprises incorporating a "step" into the confronting faces of the armature and stator at their interface across the air gap. The other way comprises guiding the armature motion by means of a brass tube with sufficiently small running clearance such that pneumatic damping occurs.

Abstract: The evaporative emission control system for an internal combustion engine purges the vapor collection canister to the intake manifold through a purge regulator controlled by the engine ECU. The purge regulator comprises a diaphragm valve and an electronic vacuum regulator. The purge regulator functions to allow a purge flow rate correlated with a control signal from the engine ECU and manifold vacuum, to maintain the purge flow rate substantially constant in response to certain changes in the magnitude of manifold vacuum, and to re-adjust the purge flow rate in correlation with changes in the control signal from the engine ECU. The diaphragm valve comprises a tapered valve element that progressively reduces the flow restriction as the valve element is increasingly opened.

Abstract: The evaporative emission control system for an internal combustion engine purges the vapor collection canister to the intake manifold through a purge regulator controlled by the engine ECU. The purge regulator comprises a diaphragm valve and an electronic vacuum regulator. The purge regulator functions to allow a purge flow rate correlated with a control signal from the engine ECU and manifold vacuum, to maintain the purge flow rate substantially constant in response to certain changes in the magnitude of manifold vacuum, and to re-adjust the purge flow rate in correlation with changes in the control signal from the engine ECU. The diaphragm valve comprises a tapered valve element that progressively reduces the flow restriction as the valve element is increasingly opened.

Abstract: A vacuum boost valve senses when the intensity of vacuum from a variable intensity vacuum source is about to drop below a threshold and supplies a boost so that when the intensity of the vacuum source is within a range immediately below the threshold, the intensity of vacuum delivered to a load does not drop below the intensity of the vacuum source and is in fact increased over what it would otherwise be without the boost. The vacuum boost is obtained by using a venturi.

Abstract: A canister purge solenoid valve is constructed and arranged to provide reduced operating noise and decreased armature wear as the armature reciprocates within a bore in response to solenoid energization and de-energization. The armature contains an elastomeric valve head that is biased normally closed against the valve seat. When the solenoid assembly is energized, the armature is retracted. The armature's momentum is initially absorbed by the elastomeric valve head making contact with the solenoid assembly at one end of the bore. Final absorption of the armature's momentum is shared by continuing contact of the valve head with the solenoid assembly and by an elastomeric limit stop that is disposed between the armature and the stator. In this way the elastomeric limit stop is not required to absorb the full momentum of the retracting armature.