Patent ID: 7258640

Claim:
An apparatus for compensating the viscous characteristics of a hydraulic medium in a pressure line ( 10 ), the apparatus comprising: a first pressure nozzle ( 12 ) and at least one channel-shaped area ( 11 , 28 ) connected in series in the pressure line ( 10 ), and the at least one channel shaped area ( 11 , 28 ) being located one of upstream and downstream of the first pressure nozzle ( 12 ); the first pressure nozzle ( 12 ) being of constant geometry and a constant through-flow crass-section; the at least one channel-shaped area ( 11 , 28 ) having a smaller through-flow cross-section and a larger axial extension than the first pressure nozzle ( 12 ); a control pressure line ( 13 ), connected between the channel-shaped area ( 11 , 28 ) and the first pressure nozzle ( 12 ), to provide a control pressure (P_SekV) to a shift valve ( 14 ); and said channel-shaped area ( 11 ) being at least one spiral duct ( 28 ) on the outer periphery of a pressure nozzle ( 27 ).