The Design of a Novel High Frequency Digital Valve Based on Rotating and Differentially Parallel Control

Abstract

Due to the ability of the strong anti-interference and directly digital controlling, digital valve has great applications and developing potential in the filed of high frequency response digital servo valve. Base on the rotating structure, a novel high frequency digital valve which can be rotated and controlled in differential parallel way is designed, and the frequency characteristic of electrical signals converting into rotation signals is developed through differential and parallel control of valve spool and valve sleeve. Meanwhile, the hydraulic natural frequency of servo-screw mechanism is further enhanced by the control way of hydraulic half-bridge type A in both chambers of valve spool, and corresponding mathematical model and control block diagram are built. Theoretical analysis concludes that the frequency response characteristic of digital valve is developed significantly. In addition, the multi-gain of rotation angle and axial displacement of valve spool is realized through milling the spiral grooves with different helix angles in the inside of valve sleeve, which improves the flow adaptability of high frequency digital valve effectively. Compared to traditional rotary digital valve, the designed novel digital valve that can be controlled by rotating differentially and parallel has greater advantages in high frequency response and flow adaptability, it provides a new scheme for engineering applications of high frequency digital valve.