Abstract: A purge control valve control system is provided for an internal combustion engine system, comprising: a voltage source having a positive potential and a negative potential; a purge control valve having a solenoid, such solenoid comprising an electrically inductive element, such inductive element having a first terminal coupled to the positive potential of the voltage source; a diode having an anode and a cathode. The control unit includes a transistor having: a control electrode fed by a train of pulses; a first electrode coupled to the negative potential of the voltage source; and a second electrode coupled to a second terminal of the inductive element and to the diode.

Abstract: A low noise valve assembly (24) mitigates noise induced by near sonic gas flow encountering stagnant flow in the region of the valve (24). An inlet tube (10) terminates in an annular chamber (12). An outlet tube (17) has a generally annular valve seat (14) disposed within the chamber (12). The valve (24) moves toward and away from a closed condition in direct contact with the valve seat (14). The valve (24) includes an insert body (26) that is spatially segregated from direct contact with the outlet tube (17) while partially filling the flow channel (16) of the outlet tube (17) when the valve (24) is in its closed condition. The insert body (26) has a generally circular base with a diameter that is larger than the throat diameter (T), which is the internal diameter of the flow channel (16) adjacent the valve (24).

Abstract: A low noise valve assembly (24) mitigates noise induced by near sonic gas flow encountering stagnant flow in the region of the valve (24). An inlet tube (10) terminates in an annular chamber (12). An outlet tube (17) has a generally annular valve seat (14) disposed within the chamber (12). The valve (24) moves toward and away from a closed condition in direct contact with the valve seat (14). The valve (24) includes an insert body (26) that is spatially segregated from direct contact with the outlet tube (17) while partially filling the flow channel (16) of the outlet tube (17) when the valve (24) is in its closed condition. The insert body (26) has a generally circular base with a diameter that is larger than the throat diameter (T), which is the internal diameter of the flow channel (16) adjacent the valve (24).