Camshaft adjuster
View Patent ↗An arrangement of a camshaft phaser ( 1 ) which allows a variable pressure boost in that a rotary piston ( 7 ) of the camshaft phaser ( 1 ) either creates or eliminates a fluid connection between a first pair of working chambers and a second pair of working chambers arranged in the axial direction ( 23 ).
1. A camshaft phaser comprising:
a drive element;
a first driven element; and
a second driven element, each of the drive, first driven and second driven elements being arranged coaxially to a rotational axis of the camshaft phaser, the first and second driven elements and the drive element having several radially oriented vanes forming several working chambers pressurizable with a hydraulic medium so that a relative rotation is possible between the drive element and one of the first and second driven elements; and
a rotary piston for purposes of controlling the pressure charging of the working chambers, the rotary piston arranged with a piston rotational axis axis-parallel to the rotational axis and opening or closing hydraulic medium-channels by rotating around the piston rotational axis.
2. The camshaft phaser as recited in claim 1 wherein the rotary piston is actuated by hydraulic-medium pressure.
3. The camshaft phaser as recited in claim 1 wherein the rotary piston connects a first pair of working chambers formed by the first driven element together with the drive element to a second pair of working chambers formed by the second driven element together with the drive element so that fluid can flow through.
4. The camshaft phaser as recited in claim 1 wherein the rotary piston connects two working chambers of a first pair of working chambers formed by the first driven element together with the drive element or two working chambers of a second pair of working chambers formed by the second driven element together with the drive element so that fluid can flow through.
5. The camshaft phaser as recited in claim 1 wherein the first and second driven elements are non-rotatably coupled to each other.
6. The camshaft phaser as recited in claim 1 wherein the rotary piston ( 7 ) is arranged coaxially to one of the first and second driven elements or to the drive element.
7. The camshaft phaser as recited in claim 1 further comprising a spring element moving the rotary piston into a resting position.
8. The camshaft phaser as recited in claim 1 further comprising an angular stop between the rotary piston and one of the first and second driven elements.
9. The camshaft phaser as recited in claim 1 further comprising a latch non-rotatably coupling one of the first and second driven elements to the drive element.
10. The camshaft phaser as recited in claim 1 herein the rotary piston is mounted on a camshaft.
11. The camshaft phaser as recited in claim 1 wherein the first and second driven elements are rotatable relative to each other.