Hydraulic balance valve Excavator hydraulic cylinder valve core CBCH-LJN

The direct acting valve and the pilot valve are divided according to the structure of the valve, the most basic difference between the two is that the direct acting valve has only one body, and the pilot valve has two bodies. One is the main valve body and the other is the auxiliary valve body. Among them, the main valve body is not much different from the direct acting type in structure; The auxiliary valve body is also called the pilot valve, which is actually equivalent to a small-flow direct-acting valve.
In principle, the similarities between direct-acting valves and pilot-operated valves are to control the opening and closing of the valve core through the imbalance of the force acting on the heart of the main valve (including oil pressure and spring force, etc.). The direct acting type is that the pressure oil (oil) of the system directly acts on the heart of the main valve and balances with other forces (such as spring force) to control the opening and closing action of the valve core; The pilot type is changed by opening and closing the valve core of the auxiliary valve (pilot valve)
The balance of the force on the heart of the main valve is used to control the opening and closing action of the main valve center. For the main valve heart
For example, because the pilot valve uses the auxiliary valve core to change the balance of the main valve force, instead of
Directly by the oil pressure to change the balance of the main valve valve force, so there is a direct type with the direct type of "indirect" called.