Active hydraulic control pressure system for adverse G flight conditions

摘要

An hydraulic control system for an IDG includes in flow series arrangement a scavenge pump, a spool valve and a boost pump. When the spool valve detects an interruption in the supply pressure to the boost pump due to an adverse "g" condition, it reconfigures the system to a closed loop system. In this mode, the oil returning from the CVT is re-circulated back to the boost pump instead of back to the scavenge pump. A small accumulator of oil is used to make up for leakage in the system.