Patent attributes
A variable camshaft timing (VCT) control valve assembly includes: a control valve having one or more lands and a valve cavity; one or more cavity vents in the control valve are configured to communicate fluid between an outer surface of the control valve and the valve cavity; a valve sleeve having a sleeve cavity that receives the control valve and a plurality of apertures, at least one of the apertures is configured to be in fluid communication with an advance fluid chamber of a VCT device and another of the apertures is configured to be in fluid communication with a retard fluid chamber; the control valve slides axially relative to the valve sleeve; and one or more reed valves, attached to an outer surface of the valve sleeve, configured to control the flow of fluid between one of the advance fluid chamber or the retard fluid chamber and the other of the advance fluid chamber or the retard fluid chamber.
