NON-RETURN VALVE OF A CAMSHAFT ADJUSTER

A camshaft adjuster with a drive element, a driven element, and a pressure chamber formed between the drive element and the driven element for generating a relative rotation between the driven element and the drive element, and a volume accumulator that is arranged in the camshaft adjuster and supplies hydraulic medium via a channel from the volume accumulator to the pressure chamber if there is an under-pressure in the pressure chamber. The camshaft adjuster has a non-return valve with a closing part for closing an opening of the channel, the non-return valve allows a flow of hydraulic medium through the channel from the volume accumulator to the pressure chamber, and there is an elastically expandable component that projects into the channel and can be guided by the channel and is connected to the closing part and is provided for applying tension for pulling the closing part into the channel.