| Fluidic technique was birthed in the beginning of the 20th century, and flourished during 1960s to 1970s. A vast majority of outstanding theories came out, and Chinese researchers brought the technique into drilling mechanics, worked out hydrolytic efflux hammer, which is critical to the development of rotary percussion drilling. However, this hammer has not been widely used until these days. Among many shaping factors, above all is the reliability of its control mechanism. Fluidic element's working life is merely tens of hours or even less during drilling process, which becomes a heavy burden of rotary percussion drilling.According to the summary and analysis of the theories and tests, this thesis stands on that it is urgent to research the design theories and working mechanism of fluidic elements, which is vital to the development of efflux hammer. Through the principle of theories coupled with tests, this paper attained several achievements as follows:1) Designed fluidic element and its accessory device, tested the reliability of the element, based on experiments.2) Based on orthogonal test design theory, this paper designed several structures of the element, and laboratory test was carried out.3) According to the results of orthogonal test, coupled with its geometric structure, this paper deduced the law of each structure parameter for influencing the whole device.4) Used thin wire and PMMA assemble to observe the track of the jet-flow.5) Based on hydraulic drive theories, this thesis made a simulation analysis of the dynamic characteristics for hydrolytic efflux hammer, and designed its structure fundamentally.Yet the working condition of hydrolytic efflux hammer is rather complex, and it is difficult to predict the causes of the failure. Consequently, in order to solve the problem of the reliability, theories should join hands with practical application, which is the future work of this paper, and the critical approach to improve the hammer.
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