Patent ID: 7261072

Claim:
A device ( 101 ) for altering the control times of gas exchange valves of an internal combustion engine, having a hydraulic actuating device ( 102 ), which has two oppositely acting pressure chambers ( 106 , 107 ), it being possible for a phase position (φ) of a camshaft relative to a crankshaft to be held or deliberately altered by feeding pressure medium to and discharging pressure medium from the pressure chambers ( 106 , 107 ), and having a control valve ( 103 ) with two working ports (A, B), an outlet port (T) and an inlet port (P), the first working port (A) being in communication with the first pressure chamber ( 106 ), the second working port (B) being in communication with the second pressure chamber ( 107 ), and the outlet port (T) being in communication with a tank, and the inlet port (P) being supplied with pressure medium, the control valve ( 103 ) comprising a valve body ( 114 ) and an actuating unit ( 112 ), it being possible for the control valve ( 103 ) to be moved into a plurality of control positions ( 130 , 131 , 132 , 140 ) by means of the actuating unit ( 112 ), the working ports (A, B) in each case being in communication either with the outlet port (T), the inlet port (P) or with neither of these two ports, depending on the control position ( 130 , 131 , 132 , 140 ) of the control valve ( 103 ), characterized in that in a first control position ( 140 ) of the control valve ( 103 ), which corresponds to the control position with the actuating unit ( 112 ) unactivated, neither the first working port (A) nor the second working port (B) is in communication with the inlet port (P).