Schaeffler Technologies Ag & Co .kg

Stefan Kramer

Olaf Boese

David Köhler

The invention relates to a camshaft adjusting system () for an internal combustion engine of a motor vehicle, including a hydraulic camshaft adjuster () which has a stator (), a rotor () that is rotatably mounted in the stator (), and a hydraulic control system () that has a valve (). The rotor () has at least one vane which protrudes into a pressure chamber formed between the rotor () and the stator () such that the pressure chamber is divided into two sub-chambers, each of which interacts with the hydraulic control system () such that a hydraulic pressure ratio is established between the two sub-chambers, said ratio specifying a relative rotational position between the rotor () and the stator (), and is adjusted on the basis of the position of the valve (). The camshaft adjusting system also includes an actuator () which is arranged adjacently in the axial direction of the camshaft adjuster () and which acts on the valve () for adjusting purposes. A hydraulic fluid section () is arranged on an actuator () face facing the camshaft adjuster (), with this hydraulic fluid section () being designed to deflect a flow of hydraulic fluid exiting the valve () into the surroundings of the camshaft adjuster () back into the camshaft adjuster () in an operational state.

Camshaft adjusting system with means for catching hydraulic fluid draining from a valve in order to directly recirculate the fluid into the camshaft adjuster

Control valves for a hydraulic camshaft adjuster are disclosed. In one example, the control valve includes a housing and a control piston mounted in a receiver of the housing. Several openings may be provided on an inner casing surface of the receiver, at least some of which may be assigned to an inlet port P, a supply port A, a supply port B or a supply port C. The control piston may include a first control groove, a second control groove and a third control groove which can each be connected to at least two openings of the housing depending on a position of the control piston relative to the housing. The first control groove may be configured to be brought into fluid-conductive connection with a first inlet opening assigned to the inlet port P and with an opening assigned to the supply port A. The second control groove may be configured to be brought into fluid-conductive connection with an opening assigned to the supply port A and/or with an opening assigned to the supply port B and/or with an opening assigned to the supply port C. The third control groove may be configured to be brought into fluid-conductive connection with the first inlet opening or a second inlet opening assigned to the inlet port P and with an opening assigned to the supply port B.

Growing community of inventors

Hochstadt/Aisch, Germany

Stefan Kramer