At ordinary times can see the basic control principle of hydraulic control valve in accordance with the valve classification can be divided into: 1, switch control valve;
By manipulating port connectivity or truncate, to control the hydraulic system of each port in the link relations of elements, commonly referred to as the switch control valve, the valve for each channel, the only two working position, open or close to the direction of the control valve usually belong to the switch valve.
2, fixed value control valve;
The components of the basic control principle, is given by its internal device (
Is one of the hydraulic system parameters (
Keep constant value, the ordinary pressure control valve are fixed value valve.
3, proportional control valve;
This is a kind of to a given input signal change law continuously control was accused of parameters (
Pressure and flow)
Element, is accused of signal is proportional to the input signal change, all kinds of electro-hydraulic proportional valve belong to a proportional control valve;
4, servo control valve;
The basic principle is that, according to the input signal and feedback signal of difference (
Automatically adjust the control parameters such as pressure and flow of liquid.
On excavators, mostly adopted in pump governor servo control valve and servo piston pump for adjusting control.