Camshaft adjusting device

1. A camshaft adjusting device for an internal combustion engine of a motor vehicle having the following components:

a stator which is driven via a crankshaft of the internal combustion engine;

a rotor which is connected in a rotationally fixed manner to the camshaft; and

a piston that has a cavity in which the rotor is arranged,

wherein a rotary angle position of the rotor is varied with respect to the stator by way of the piston which is displaced in a radial direction.

2. The camshaft adjusting device according to claim 1 , wherein displacement movement of the piston is turned into a rotational adjusting movement of the rotor by way of an engagement means which acts eccentrically on the rotor.

3. The camshaft adjusting device according to claim 1 , wherein the piston is spring loaded with respect to the stator by at least one spring means.

4. The camshaft adjusting device according to claim 3 , wherein the spring means comprise two or more springs which act counter to one another.

5. The camshaft adjusting device according to claim 1 , wherein the rotor divides the cavity of the piston into two working chambers.

6. The camshaft adjusting device according to claim 5 , wherein one working chamber between the piston and the rotor and one working chamber between the piston and the stator have a common pressure medium supply.

7. The camshaft adjusting device according to claim 1 , wherein the piston is arranged in a cavity of the stator and divides the cavity of the stator into at least two working chambers.

8. The camshaft adjusting device according to claim 7 , wherein one working chamber between the piston and the rotor and one working chamber between the piston and the stator have a common pressure medium supply.

9. The camshaft adjusting device according to claim 1 , wherein the piston is arranged in a cavity of the stator, and the cavity has two guide faces which lie opposite one another, are arranged parallel to one another and on which the piston is guided.