Designing Of Gas-Liquid Ejection Mechanism & Investigation Of The Key Control Component

Eject launcher is widely used in the field of military, such as missile or rocket ejection, ship-based aircraft launching, unmanned fighter plane or life-seat lifting-off or even launching of satellite from space-station, aerospace plane or other flight devices. The application of ejection mechanism usually has a strict demand on its weight and performance, even much stricter on the dynamic response of its control components. Therefore a 2D digital servo valve is designed to meet these demands. The valve is developed with both rotary and linear motions of a single spool. The rotary motion incorporating a spiral groove on the spool land and a couple of high and low pressure holes in the spool cavity controls pressure of the spool chamber, while the linear motion of the spool is actuated by the hydrostatic force. A step motor is used to actuate the rotary motion of the spool and thus digitally realize the mechanical-to-electrical interfacing of the valve. The mathematical model is established and simulation analysis, is carried out. To verify the feasibility of the valve, the prototype is manufactured and tested. The measured result shows that the time elapse of the valve for step input is about 3～5 ms. Besides, it also possesses other favorable features, such as small volume, light-weighted, and good stability.The main tasks of this dissertation are listed as followed,Chapter I : Some correlative information with eject launcher and electro-hydraulic valves were introduced at first. And then purpose and meaning of the study were proposed.Chapter II: A gas-hydraulic eject launcher was designed. And then its main mechanical components were designed in detail. Chapter III: The mathematical model of key control component of the eject launcher was established. And then the simulation was done to the 2D digital servo valve based on the environment of the software Malab. With help of the good simulation results, each mechanical part of the 2D digital servo valve was designed precisely.Chapter IV: A experiment system was built to test the dynamic response and the leakage character of the 2D digital servo valve, and another was built to test performance of the gas-hydraulic eject launcher with three 2D digital servo valves installed on it. And then the measured results were all analyzed carefully.ChapterV: The summarization of this dissertation and the prospect of this research are given.