HYDRAULIC PRESSURE SUPPLY SYSTEM

To suppress the lowering of line pressure in a process in which a discharge flow rate of a working fluid from a first oil pump is continuously reduced while suppressing the deterioration of the durability of a second oil pump.SOLUTION: Since an operation of an EOP 60 is started from a time point at which the lowering of a discharge flow rate of a MOP 58 is predicted or detected, even if the discharge flow rate of the MOP 58 becomes insufficient, PL actual pressure which should be acquired at PL indication pressure which is set to a value corresponding to necessary transmission torque Tcbn can be easily maintained. Also, since the PL indication pressure is set to a value higher than a value corresponding to the necessary transmission torque Tcbn after the lapse of a prescribed time TMa after a time point at which the operation of the EOP 60 is started, and a regulator valve 116 is controlled so as to be operated to a side for closing a drain port 120, it is prevented that the EOP 60 is operated in a state that the PL actual pressure is high, and a response delay of a pressure regulation operation of the regulator valve 116 in the process in which the discharge amount of the MOP 58 is continuously reduced is suppressed.SELECTED DRAWING: Figure 6 【課題】第２オイルポンプの耐久性の悪化を抑制しつつ、第１オイルポンプからの作動油の吐出流量が減少していく過程におけるライン圧の低下を抑制する。【解決手段】ＭＯＰ５８の吐出流量の低下が予想又は検知された時点からＥＯＰ６０の運転が開始させられるので、ＭＯＰ５８の吐出流量が不足しても、必要伝達トルクＴcbnに応じた値に設定されたＰＬ指示圧にて得られるはずのＰＬ実圧を維持し易くされる。又、ＥＯＰ６０の運転を開始した時点から所定時間ＴＭａ経過後にＰＬ指示圧が一時的に必要伝達トルクＴcbnに応じた値よりも高い値に設定されて、ドレンポート１２０を閉じる側に動作するようにレギュレータバルブ１１６が制御されるので、ＰＬ実圧が高い状態でＥＯＰ６０が運転させられることが抑制されると共に、ＭＯＰ５８の吐出流量が減少していく過程におけるレギュレータバルブ１１６の調圧動作の応答遅れが抑制される。【選択図】図６