PROBLEM TO BE SOLVED: To extend a pump life by equalizing loads of both hydraulic pumps on the premise that it is a two-pump system.SOLUTION: A shovel circuit structured to separate a hydraulic actuator group into two groups G1, G2 and the groups are respectively driven by first and second hydraulic pumps 20, 21 is connected with processor actuators for wood processing. To conduct a small merge control, discharged oil of both the hydraulic pumps 20, 21 are merged and supplied for a hydraulic actuator of the processor actuators which is suitable for a single flow of which maximum required flow rate can be supplied only by one of the hydraulic pumps in a flat-topped state in which total of respective discharge flow rates becomes equivalent to the above single flow.COPYRIGHT: (C)2010,JPO&INPIT【課題】2ポンプシステムを前提として、両油圧ポンプの負荷を均等化してポンプ寿命を高める。【解決手段】油圧アクチュエータ群を二つのグループG1,G2に分け、第1、第2両油圧ポンプ20,21によってグループ別に駆動するように構成されたショベル回路に、木材処理用のプロセッサアクチュエータを接続し、このプロセッサ用アクチュエータのうち、最大必要流量が一方の油圧ポンプのみによって賄い得る単流相当である油圧アクチュエータに対し、両油圧ポンプ20,21の吐出油を、それぞれの吐出流量の合計が上記単流相当となる頭切り状態で合流させて供給する小合流制御を行うように構成した。【選択図】図1
