Patent ID: 6569044
Filing Date: 2003-05-27
Classification: F16H,Y10T

Abstract:
An emergency hydraulic control for a gear-ratio-dependent variation of hydraulic oil pressures in a first and a second hydraulic bevel gear axial adjuster of a continuous variable loop transmission, the emergency hydraulic control comprising a pump which directly supplies at least a piston chamber of the second axial adjuster; at least one secondary valve limiting an oil pressure; a first electromagnetically actuated pressure limiting valve which is connected downstream of said secondary valve for remote control of said secondary valve; a first orifice valve disposed in a lead line to said first electromagnetically actuated pressure limiting valve; a control line for remote control of said secondary valve branching off downstream of said first orifice valve; a continuous-path valve supplied from a lead line to said piston chamber of said second axial adjuster so that a valve of a piston chamber of said first axial adjuster is supplied with pressure fluid; a throttle valve disposed between the lead line to said piston chamber of said second axial adjuster and said continuous-path valve; a second electromagnetically actuated pressure limiting valve which is connected downstream of said secondary valve and hydraulically controls said continuous-path valve; a second orifice valve disposed in a lead line of said second electromagnetically actuated pressure limiting valve; a further control line for controlling said continuous-path valve branching off downstream of said second orifice valve; a pressure limiting valve which limits a pressure in a lead line to said piston chamber of said second axial adjuster, said pressure limiting valve communicating via an additional control line with said control line for controlling said continuous-path valve; a third orifice valve disposed between a discharge point of said additional control line into said control line for controlling said continuous-path valve, and a branching point of said control line for controlling said continuous-path valve from a lead line to said first electromagnetically actuated pressure limiting valve.