Excavator Hydraulic Spool Control for Simultaneous Boom and Arm Operation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Simultaneous operation of the boom and arm in excavators results in pressure loss due to flux passing through secondary control spools, which affects efficiency.
Innovation Solution
The method involves supplying the first flux to the boom cylinder through only the first boom control spool and the second flux to the arm cylinder through only the first arm control spools, with selective control of the second arm and boom control spools using joysticks to minimize pressure loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the first flux is partially supplied to the arm cylinder through the second arm control spool and the second flux is partially supplied to the boom cylinder through the second boom control spool during simultaneous operation, then both boom and arm can be operated simultaneously, but pressure loss is generated
Solution Approach 1:
The hydraulic system is segmented into dedicated pathways: the first flux from the first hydraulic pump is assigned exclusively to the boom cylinder through the first boom control spool, and the second flux from the second hydraulic pump is assigned exclusively to the arm cylinder through the first arm control spool. This segmentation eliminates cross-flow through secondary control spools, resolving the pressure loss issue while preserving simultaneous operation capability
Solution Approach 2:
The control system acts as an intermediary by selectively controlling the opening and closing of control spools based on operation mode. During simultaneous operation, the controller closes the second arm control spool and second boom control spool to eliminate unnecessary flux pathways, thereby reducing pressure loss while maintaining the ability to supply flux to both cylinders
2Adaptability or versatility
If the second arm control spool and second boom control spool are used during simultaneous operation, then flux distribution flexibility is improved, but pressure loss increases
Solution Approach 1:
The control spools are dynamically controlled based on operation mode. During simultaneous operation, the second arm control spool and second boom control spool are closed to eliminate pressure loss, while the first arm control spool and first boom control spool remain open to maintain flux supply. This dynamic control preserves flexibility when needed while eliminating pressure loss during simultaneous operation
Solution Approach 2:
The system changes the flow distribution parameters by selectively opening and closing control spools. When simultaneous operation is detected, the controller changes the state of the second arm control spool and second boom control spool from open to closed, thereby changing the flux distribution parameters to eliminate pressure loss while maintaining operational flexibility
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces pressure loss and enhances operational efficiency by optimizing flux distribution during simultaneous boom and arm operations.
Implementation Method 1
a first flux generated from a first hydraulic pump and a second flux generated from a second hydraulic pump may be supplied to the boom cylinder or the arm cylinder through the first and second boom control spools or the first and second arm control spools
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In a method of controlling a main control valve of an excavator, when speeds of a boom cylinder and an arm cylinder may be increased by handling a boom joystick and an arm joystick, a second arm control spool between a first hydraulic pump and the arm cylinder may be closed. A first boom control spool between the first hydraulic pump and the boom cylinder may be opened to supply a first flux generated from the first hydraulic pump to the boom cylinder. A second boom control spool between a second hydraulic pump and the boom cylinder may be closed. A first arm control spool between the second hydraulic pump and the arm cylinder may be opened to supply a second flux generated from the second hydraulic pump to the arm cylinder. Therefore, a pressure loss caused by passing of the flux through the second boom control spool and the second arm control spool may be reduced.