A retard supply check valve is installed in a retard supply passage and is located on a side of a hydraulic oil controller where a hydraulic oil supply source is placed. The retard supply check valve enables only a flow of hydraulic oil from the hydraulic oil supply source toward a retard chamber. An advance supply check valve is installed in an advance supply passage and is located on the side of the hydraulic oil controller where the hydraulic oil supply source is placed. The advance supply check valve enables only a flow of the hydraulic oil from the hydraulic oil supply source toward an advance chamber.

An ECU (101) causes lock pin-release hydraulic pressure to be applied to an advance-side lock pin-release oil passage (5a) to disengage an advance-side lock pin (6) from an advance-side engagement groove (9), thereby making a rotor (1) rotatable in an advance direction, and forming a clearance communicating with a retard-side lock pin-release oil passage (5c), between the advance-side engagement groove (9) and the advance-side lock pin (6). Next, the ECU (101) causes hydraulic pressure to be applied to advancing hydraulic chambers (16) to rotate the rotor (1), and causes the lock pin-release hydraulic pressure to be applied through the clearance and through the retard-side lock pin-release oil passage (5c) to a retard-side engagement groove (10) to disengage a retard-side lock pin (7).

A variable camshaft phaser is provided having a stator attached to a driving part, and a rotor located within the stator and attached to a driven part. First and second cover plates are located on respective first and second axial sides of the stator. Inwardly directed vanes of the stator, the rotor, and the first and second cover plates define at least one chamber. Radially outwardly directed vanes of the rotor divide the at least one chamber into an advance side working chamber and a retard side working chamber. A locking pin bore is located in the rotor, and a locking pin is located in the locking pin bore. One of the first and second cover plates includes a locking pin receiving opening. A magnetic part is located in the locking pin receiving opening to remove metallic particles and contaminants from the flow of pressurized hydraulic fluid.

A camshaft phaser is provided that includes a stator and a rotor having a locking assembly. The locking assembly has a first unlocked position and a second locked position and is configured to roll against the stator in the first unlocked position and lock the rotor to the stator in the second locked position. The locking assembly can include a locking pin, a retention insert, and a rolling element arranged within the retention insert.

A spool is configured to reciprocate at an inside space of a sleeve and includes: a spool tube; a spool cover, which closes an end portion of the spool tube located on a camshaft side; a pressure accumulation space, which is formed at an inside of the spool tube; a supply passage, which is configured to connect between the pressure accumulation space and a supply port; a control passage, which is configured to connect between the pressure accumulation space and a primary control port; and a control passage, which is configured to connect between the pressure accumulation space and a secondary control port. A variable volume space is formed between the spool cover and a sleeve bottom. The sleeve includes a breathing hole at an outside of the inside space while the breathing hole is a hole that communicates between the variable volume space and the atmosphere.

A hydraulic camshaft adjuster adjusts the control time of gas exchange of an internal combustion engine. A reservoir for storing pressure medium is formed on a cover of the hydraulic camshaft adjuster. An overflow opening of the cover is dimensioned such that a volume of pressure medium remains in the reservoir when the hydraulic camshaft adjuster is stationary. This ensures that pressure medium is supplied to the return valve of a central locking mechanism when the engine is running.

An internal combustion engine valve timing control device includes a communication passage formed in a first rotating member to communicate with a working chamber, and including a first opening. The first opening is opened to a back pressure chamber when a tip portion of a lock member is inserted in a lock hole, and is closed by the lock member when the tip portion of the lock member is out of the lock hole. A first cross-sectional area is smaller than a second cross-sectional area, wherein the first cross-sectional area is a smaller one of a minimum cross-sectional area of the communication passage and an open cross-sectional area of the first opening, and the second cross-sectional area is a smaller one of a minimum cross-sectional area of an exhaust passage and an open cross-sectional area of an opening of the exhaust passage opened to the back pressure chamber.

A camshaft phaser includes a stator defining a cavity and configured to receive power from an engine crankshaft. The phaser further includes a rotor supported within the cavity and rotatable relative to the stator. The rotor has a first face, a second face, and a first hole extending from the first face to the second face. A target wheel of the phaser has a plate portion configured to be read by a camshaft-position sensor and a hub portion seated on the first face. The hub portion defines a second hole that is aligned with the first hole. A pin extends through the first and second holes to rotationally align and secure the target wheel to the rotor.

A variable camshaft phaser is provided having a stator attached to a driving part, and a rotor located within the stator and attached to a driven part. First and second cover plates are located on respective first and second axial sides of the stator. Inwardly directed vanes of the stator, the rotor, and the first and second cover plates define at least one chamber. Radially outwardly directed vanes of the rotor divide the at least one chamber into an advance side working chamber and a retard side working chamber. A locking pin bore is located in the rotor, and a locking pin is located in the locking pin bore. One of the first and second cover plates includes a locking pin receiving opening. A magnetic part is located in the locking pin receiving opening to remove metallic particles and contaminants from the flow of pressurized hydraulic fluid.

A valve timing control device includes: a first clearance being formed between a radial other side of the outer circumference surface of the first shaft portion, and a confronting end surface of a radial other side of the inner circumference surface of the sliding hole, a second clearance being formed between an outer circumference of the second shaft portion on a side of the first clearance, and a radial other side of the inner circumference surface of the lock recessed portion, a stepped surface being formed at a connection portion between the first shaft portion and the second shaft portion, and having a stepped width in a radial direction, and a width of the second clearance being substantially identical to the width of the stepped surface.