Suitable for E320 330 336GC proportional solenoid valve 585-9231 excavator accessories

How does the proportional valve work

    Automatic control can be divided into intermittent control and continuous control. Intermittent control is switch control. In the pneumatic control system, an ON-OFF reversing valve with a lower operating frequency is used to control the on-off of the gas path. Rely on the pressure reducing valve to adjust the required pressure, rely on the throttle valve to adjust the required flow. This traditional pneumatic control system wants to have multiple output forces and multiple motion speeds, it needs multiple pressure reducing valves, throttle valves and reversing valves. In this way, not only the components need more, the cost is high, the composition of the system is complex, and many components need to be manually adjusted in advance. The electrical proportional valve control belongs to continuous control, which is characterized by the output quantity changes with the input quantity (current value or voltage value), and there is a certain proportional relationship between the output and the input quantity. Proportional control can be divided into open loop control and closed loop control. Closed-loop control of the signal feedback system. Electro-hydraulic proportional valve is the proportional electromagnet input voltage signal in the valve to produce corresponding action, so that the working valve spool displacement, valve port size change and complete the pressure and flow output components proportional to the input voltage. Spool displacement can also be fed back mechanically, hydraulically or electrically. Electro-hydraulic proportional valve has a variety of forms, easy to use electrical and computer control of various electro-hydraulic systems, high control accuracy, flexible installation and use, and strong anti-pollution ability, and other advantages, the application field is expanding. Electric proportional valve automatic selection and collection, R & D and production of cartridge proportional valve and proportional multiway valve fully consider the characteristics of the use of construction machinery, with pilot control, load sensing and pressure compensation functions. It is of great significance to improve the overall technical level of mobile hydraulic machinery. In particular, electronic control pilot operation, wireless remote control and wired remote control operation have shown good application prospects. Principle: The input signal increases, the air supply solenoid valve pilot valve 1 reverses, and the exhaust solenoid pilot valve 7 is in the reset state, then the air supply pressure enters the pilot chamber 5 from the SUP port through valve 1, the pressure of the pilot chamber rises, the gas pressure acts on the upper part of the diaphragm 2, then the air supply valve core 4 connected with the diaphragm 2 is opened, the exhaust valve core 3 is closed, and the output pressure is generated. This output pressure is fed back to control loop 8 through pressure sensor 6. Here, a quick comparison is made with the target value until the output pressure is proportional to the input signal, resulting in a change in the output pressure proportional to the change in the input signal. Because there is no nozzle baffle mechanism, the valve is not sensitive to impurities and has high reliability.