General Information (Main Control Valve)
主控制阀位于主液压泵和机具油缸、行驶马达和回转马达之间的液压回路上。 主液压泵将高压液压油供应至主控制阀。 ECM 使用先导歧管中的先导压力油来指令主控制阀中九个主滑阀的移动。 九个主阀滑阀进而控制流向机具油缸和马达的高压油流。 主控制阀按照操纵手柄和行驶操纵杆/踏板的移动比例，确定机具油缸和马达的方向和速度。 九个主阀滑阀控制下述部件：
- 动臂油缸（升起和降下）
- 斗杆油缸（缩回和伸出）
- 铲斗油缸（开启和闭合）
- 辅助系统（供油和回油）
- 回转动臂油缸（向左和向右）
- 回转马达（左侧和右侧）
- 左行驶马达（前进和后退）
- 右行驶马达（前进和后退）
- 铲刀油缸（升起和降下）
注: 请参阅本手册中的相应章节，了解更多信息。
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