Hydraulically-actuated vct system including a spool valve

A hydraulically-actuated variable camshaft timing (VCT) system, comprising:

• a spool valve including a sleeve and a spool, having a plurality of radially-outwardly extending lands and a spool cavity, received within the sleeve;
• a first fluid supply port in the sleeve configured to receive fluid from a fluid supply;
• a second fluid supply port in the sleeve configured to receive fluid from the fluid supply;
• and
• a spool exhaust port included with the spool cavity that is positioned axially between the first fluid supply port and the second fluid supply port, wherein the spool exhaust port and the spool cavity are configured to selectively receive fluid from an advancing chamber of a hydraulically-actuated camshaft phaser or a retarding chamber the hydraulically-actuated camshaft phaser.

A hydraulically-actuated variable camshaft timing (VCT) system, comprising:

• a spool valve including a sleeve and a spool, having a plurality of radially-outwardly extending lands, received within the sleeve;
• a first fluid supply port in the sleeve configured to receive fluid from a fluid supply;
• a second fluid supply port in the sleeve configured to receive fluid from the fluid supply;
• an advancing port in the sleeve configured to receive fluid from an advancing chamber of a hydraulically-actuated camshaft phaser;
• a retarding port in the sleeve configured to receive fluid from a retarding chamber of a hydraulically-actuated camshaft phaser;
• and
• an exhaust port axially positioned in the sleeve in between the first fluid supply port and the second fluid supply port, wherein the exhaust port is configured to receive fluid through either the advancing port or the retarding port depending on an axial position of the spool relative to the sleeve.