Abstract: A hydraulic valve, in particular for a phaser of a cam shaft, the hydraulic valve including a bushing including a piston that is displaceable in a bore hole along a longitudinal direction; a supply connection configured to supply a hydraulic fluid; at least a first operating connection and a second operating connection; and at least one tank drain configured to drain the hydraulic fluid, wherein the first operating connection and the second operating connection are alternatively connectable with each other and/or with the supply connection and/or with the at least one tank drain through at least one check valve by displacing the piston.

Abstract: 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.

Abstract: A hydraulic valve, in particular for a phaser of a cam shaft, the hydraulic valve including a bushing including a piston that is displaceable in a bore hole along a longitudinal direction; a supply connection configured to supply a hydraulic fluid; at least a first operating connection and a second operating connection; and at least one tank drain configured to drain the hydraulic fluid, wherein the first operating connection and the second operating connection are alternatively connectable with each other and/or with the supply connection and/or with the at least one tank drain through at least one check valve by displacing the piston.

Abstract: 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.