A Pilot Proportional Flow Valve with Composite Feedback Function of Position and Flow

Abstract

The invention relates to a pilot-operated proportional flow valve with position and flow composite feedback function, which includes a pilot valve and a main valve, the pilot valve includes a controller and a pilot valve module, and the main valve includes a valve body, a valve core, a left end cover, and a right end cover and spring; the pilot valve control port of the pilot valve is connected with the main valve control port of the main valve, the main valve control port of the main valve is connected with the right control chamber of the main valve, and the main valve is provided with a heat sensor for measuring the flow rate of the working port The main valve is equipped with a displacement sensor for measuring the displacement of the spool; the pressure at the control port of the pilot valve and the input signal have a first nonlinear characteristic relationship, and the relationship between the pressure at the control port of the main valve and the opening of the valve port There is a linear relationship, and there is a second nonlinear characteristic relationship between the valve opening and the output gas flow; the output gas flow and the input signal are corrected to form a linear relationship, and the value is solidified into the controller. The advantages are: suitable for gas flow control, high control precision, good stability and fast response.

Description

technical field [0001] The invention relates to the technical field of gas flow control, in particular to a pilot-operated proportional flow valve with combined position and flow feedback functions. Background technique [0002] The flow rate of fluid (gas and liquid), when the external conditions (pressure and temperature, etc.) are constant, is generally related to the size of the cross-section of the space through which the fluid flows. For a specific flow valve, it is to control the opening of the valve port to realize the output of the required flow value. [0003] The so-called proportional flow valve means that the flow output of a control valve has a linear relationship with the value of the input signal (current or voltage) applied. The so-called pilot control valve means that the movement of the spool of the main valve is controlled by the output pressure of the pilot valve. [0004] The pilot valve is generally a miniature direct-acting proportional pressure val...

AI Technical Summary

Problems solved by technology

Although the proportional flow valve with direct flow feedback can provide high-precision flow control, due to the relatively low dynamic response of the thermal flow sensor, it still cannot meet the real-time control needs of rapid response in the automation field.

The proportional flow valve with position feedback can provide high dynamic response, but the position of the spool is not the final control variable, so its control accuracy still cannot meet the stringent requirements for composition control in the field of atmosphere configuration control

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