Abstract

Background: The pre-stage deflection is a key aspect of the deflector jet tube electrohydraulic servo valve, and its performance not only affects the pressure gain, flow gain, and other important parameters of the servo valve, but also affects the dynamic and static characteristics of the servo valve and electro-hydraulic servo system.

Objective: This paper aimed to outline the working principle of the pre-stage deflector jet tube type electro-hydraulic servo valve, and review and analyze its research performance development in five aspects.

Method: The research progress in the key indexes of servo valve performance at different stages, the mechanism and phenomenon of the erosion and wear of the pre-stage, the mechanism and characteristics of the pre-stage cavitation, the structural improvement and parameter optimization of the pre-stage, as well as the pre-stage drive mode, has been summarized.

Results: It has been found that although a large number of scholars at home and abroad have improved the structure and driving mode of the front stage of the deflecting jet tubular electrohydraulic servo valve and optimized the parameters to improve the performance of the deflecting jet tubular electro-hydraulic servo valve, the internal flow field of the front stage is complex, prone to erosion and cavitation and many complex phenomena, and there are still many aspects to be improved and innovated.

Conclusion: This paper has thus summarized the defects of the front-end stage, and put forward three future innovations of miniaturization, intelligence, and multifunction, to contribute innovative ideas to the design of the front-end stage of the deflection jet pipe electro-hydraulic servo valve in the future.

Keywords: Deflector jet tubular servo valve, front stage, dynamic characteristics, static characteristics, erosion, wear, structural improvement, parameter optimization.