Patent attributes
A valve timing control apparatus for controlling valve timing includes a first rotor, a second rotor, and a controller. The second rotor and the first rotor defines therebetween an advance chamber and a retard chamber. The controller includes a supply passage, at least one drain passage, a spool valve, at least one connection passage, and at least one check valve. The at least one connection passage connects the supply passage to the at least one drain passage when a spool of the spool valve is moved to one of the advance and retard positions. The at least one check valve is respectively provided in the at least one connection passage. The check valve allows working fluid to flow in a direction from the at least one drain passage toward the supply passage and limits working fluid from flowing in an opposite direction.
