A hydraulic camshaft adjuster (1), in which the locking system (7, 8) includes a first and a second control element (7, 8). In order to approach the middle position easily, the first control element (7) has a first and a second switching position, wherein in the first switching position a fluidic connection between the hydraulic pump (P) and a first of the two sub-chambers (B) and a fluidic connection between the other, second sub-chamber (A) and the tank (T) can be established, and in the second switching position a fluidic connection between the hydraulic pump (P) and the second of the two sub-chambers (A) and a fluidic connection between the other, first sub-chamber (B) and the tank (T) can be established, and the second control element (8) is free from different switching positions and has no influence on the flow of hydraulic fluid.

In a vehicle control device with an automatic engine stop function, when the engine is in a non-operating state and the shift lever is operated to the parking range, the engine is controlled to start to supply operating oil to a valve timing changing means. The valve timing changing means is thereupon caused to change the intake valve close timing (IVC) to a predetermined advance angle position and subsequently locked thereat. The engine is then controlled to stop.

A variable valve timing control device has, as control modes for adjusting inflow and outflow of oil with an OCV, a lock mode for moving a lock pin in a locking direction, a phase control mode for controlling a camshaft phase by a target phase in accordance with an operation state of an engine, and an oil filling mode for filling an advancement chamber and a retardation chamber with the oil in a state that the lock pin moves in the locking direction, before shifting from the lock mode to the phase control mode. When the oil filling mode has been selected, a target position of a spool is set based on viscosity of the oil, and the position of the spool is controlled so as to be the set target position.

The present disclosure provides a CVVT system including: an OCV supplying oil received from a cylinder block into a CVVT; an oil supply unit supplying oil from the OCV to a lock pin; and an actuator selectively opening or closing the oil supply unit such that oil is supplied to the lock pin and the lock pin is separated from a lock pin hole when the oil supply unit is opened.

At a time of a startup in a non-lock state (at the time of a next startup in a case where an internal combustion engine is stopped in a non-lock state in which a VCT phase is not locked in an intermediate lock phase), it is determined whether or not the engine can be started up by most delayed startup processing. In a case where it is determined that the engine can be started up by the most delayed startup processing, the most delayed startup processing is performed. In this most delayed startup processing, the engine is cranked in a high rotation range not less than a specified rotation speed and a fuel injection and an ignition are started in a state in which the VCT phase is controlled to a vicinity of the most delayed phase (most delayed phase or within a specified range from the most delayed phase) to thereby start up the engine. In this way, at the time of the startup in the non-lock state, the engine can be quickly started up without locking the VCT phase.

In a hydraulically-operated vane rotor equipped variable valve timing control device for an internal combustion engine, a fluid-communication control mechanism is configured to switch, after having started the engine, a communication hole from a communicated state to a fluid-communication restricted state prior to switching operation of a lock mechanism from a lock state in which rotary motion of a vane rotor relative to a housing is restricted to an unlock state in which rotary motion of the vane rotor relative to the housing is enabled. As a result of this configuration, it becomes possible to apply, after having started the engine, an appropriately controlled hydraulic pressure to all of vanes, with hydraulic pressure supplied to either all phase-retard chambers or all phase-advance chambers, thereby ensuring a good control responsiveness of the vane rotor.

A valve opening and closing timing control device includes: a drive-side rotary body rotating synchronously with a crankshaft; a driven-side rotary body provided inside the drive-side rotary body coaxially and rotating integrally with a camshaft; advance and retard chambers formed between the drive-side and driven-side rotary bodies; a lock mechanism switchable between a lock state and a lock release state; a valve unit including a fluid supply pipe into which fluid is supplied and a spool movable along a direction of the rotation axis, and controlling supply of the fluid to and from the lock mechanism, and the advance and retard chambers; and a tubular valve case having an internal space inside the driven-side rotary body and housing the valve unit in the internal space. A first opening portion is formed in the fluid supply pipe. A second opening portion is formed in the valve case.

A valve timing control device, in effect a cam phaser, for an internal combustion engine. The valve timing control device includes a rotor connected to a camshaft and having a plurality of vanes. A stator is engaged with the rotor, and includes a plurality of webs. Pressure chambers are provided between each of the webs and vanes. The cam phaser is configured to automatically locate to its mid-lock position, without having to rely on electronic control. At least one embodiment of the present invention is configured to use cam torque to recirculate oil from one side of the vanes of the rotor to the other.

A camshaft phaser, including: a stator including radially inwardly extending protrusions with radially outermost ends; a rotor including radially outwardly extending protrusions radially outermost ends; chambers at least partially bounded by a inwardly extending protrusion and an outwardly extending protrusion; first seals disposed in the radially innermost ends and facing the rotor; second seals disposed in the radially outermost ends and facing the stator; first and second wedge plates radially disposed between the rotor and the stator; and a displacement assembly arranged to for an advance mode, displace the first wedge plate to enable rotation of the rotor, with respect to the stator, in the first circumferential direction and for a retard mode, displace the second wedge plate to enable rotation of the rotor, with respect to the stator, in a second circumferential direction opposite the first circumferential direction.

Methods and systems are described for an engine with a cam torque actuated variable cam timing phaser. Phaser positioning control is improved by reducing inaccuracies resulting from inadvertent spool valve and/or phaser movement when the spool valve is commanded between regions. In addition, improved spool valve mapping is used to render phaser commands more consistent and robust.