Electro-hydraulic proportional valve is a proportional electromagnetic valve in the valve according to the input voltage signal corresponding action, make the job displacement of valve core, valve opening size change and finish with the input voltage is proportional to the pressure and flow rate of the output element. Valve core displacement can also be in the form of mechanical, hydraulic or electric feedback. Because the electro-hydraulic proportional valve has the form of species diversity, easy to use electrical and computer control of electro-hydraulic system, high control precision, easy to install and use flexible and strong ability to resist pollution aspects of advantages, so applications increasingly widened. In recent years, research and development production of the cartridge proportional valve and proportional multi-way valve fully consider the use of characteristics of engineering machinery, pilot control, load sensing and pressure compensation, and other functions. Its emergence of mobile hydraulic machinery the overall technology level of ascension is of great significance. Especially in electric control pilot operation, wireless remote control and wired remote control, etc, showing its good application prospect.

Electro-hydraulic proportional valve including proportional flow valve, proportional pressure valve, proportional directional control valve. According to the characteristics of the engineering machinery hydraulic operation, in the form of structure electro-hydraulic proportional valve is mainly divided into two kinds: one kind is spiral cartridge proportional valve, another kind is slide valve type proportional valve.

Spiral cartridge proportional valve is electromagnetic proportional cartridge is fixed by screw thread on the hydraulic integrated block element, spiral cartridge valve pipe with flexible application, saving and low cost etc., in recent years application in engineering machinery is more and more widely. Commonly used spiral cartridge proportional valve has a two-way, three-way, four-way and more general form, two general formula proportion valves are mainly proportional throttle valve, which tend to form compound valve with other components, the flow, pressure control; Three-pass proportional valve mainly is the proportional pressure reducing valve and proportional valve mobile machinery hydraulic system is widely applied, it is mainly to pilot hydraulic system of hydraulic multi-way valve operation. Three-pass proportional pressure reducing valve can be used to replace the traditional manual pressure pilot valve, it is better than manual pilot valve with more flexibility and higher control precision. Spool or multipass spiral cartridge proportional valve can work on the device to realize individual control.

Proportional valve is also called the distributing valve valve type, is one of the most basic element of mobile machinery hydraulic system, is to realize direction combination valve with flow control. Electric hydraulic slide valve type proportional multi-way valve is ideal electro-hydraulic conversion control element, it not only retained the basic function of multi-way valve manually, also increases the position feedback servo operation and load sensing proportion and other advanced means of control. So it is the updated products engineering machinery distribution valve.

For manufacturing costs and the characteristics of construction machinery control accuracy is not high, generally within the proportional multi-way valve displacement sensor configuration, also don't have electronic detection and error correction function. So the valve core displacement easily affected by load changes caused by pressure fluctuations, operation process to ensure homework done by visual observation. In the electronic control, remote control operation more should pay attention to the influence of outside interference. Recently, due to the development of electronic technology, people are increasingly using built-in differential transformer displacement sensor such as detecting the position of valve core, valve core displacement closed loop control. The driven by electromagnetism proportion valve and position feedback sensor, amplifier and other electronic circuit consisting of a highly integrated proportional valve, have certain correction function, general proportional valve can be effectively overcome the shortcomings, improve obviously the control accuracy.

The above: Hydraulic gear pump manufacturer