Research On The Technology Of Impact Vibration Based On The Four-Way Rotary Valve

Vibration equipment can force a object vibrate. As a important way to vibrate, pound excitat ion is widely used in the field of civil construction, roads and bridges, aerospace and reliability t est, the technical level of which is directly related to the level of product performance and reliabi lity of the tests and shows the equipment manufacturing and research level of a country’s scienc e. Generally, impact test machine and electric vibrating table and shaking table can make impact test. In the analysis of their research status, this paper noted the following deficiencies:Wavef orm control performance of Impact Tester is poor; Although the waveform control performance of electronic vibration is good, its force is relatively small and its low-frequency characteristics i s poor; Although electro-hydraulic servo vibration waveform test table both has a great force an d good low-frequency characteristics, etc., its frequency bandwidth is too low. Therefore, it is v ery important to make a new electro-hydraulic test table which has high bandwidth and low pric-e.This paper research is based on the development needs of the exciter and funded by the Gov ernmental Natural Science Foundation project named the basic theory and technology of spool r otary electro-hydraulic power excitation, I proposed and designed a new electro-hydraulic excite r which is mainly consisted of DSP digital signal processor, servo motor, micro-displacement a nd double-acting hydraulic cylinders and spin valve spool. I made a rotary valve with a variety o f trench shape, and build corresponding exciter theoretical models, while simulate these models under different parameters and situations and establish experimental table which can validate the se exciter theoretical models. Also, because flow force can have a bad effect on servo-motor’s s peed while electro-hydraulic exciter is in the excitation process, the quality of excitation wavefo rm may turn bad and its amplitude and pulse width may become lower. Therefore, I made simul ation analysis of flow field in the spin valve, and established fluid dynamic theoretical model to compute flow force by the software named matlab and built a platform to make experiments wh ich can measure hydraulic flow force. As a result, it can fill the blank of exciter test table in the shock field and have certain significance in related research in the future.The research works can be summarized as follows:1. Introduce a new electro-hydraulic shock exciter component which consists of servo motor speed control systems, micro-displacement double-acting hydraulic cylinders and spin valve, an d its principle. Design the motor speed control procedures and the spin valve which is consisted a lot of components. The exciter not only can be used in the case of pound excitation, but also c an be used in high-frequency, high-pressure and high flow conditions. Furthermore, in order to explore the relationship between trench and electro-hydraulic shake waveform, I design a variet y of grooves spool which have different shapes and sizes.2. Through the use of simulation software, I made analysis study on the flow field and resear ch relationship between different parameters and flow field inside the spin valve.3. Based on the spin valve and exciter’s working principle, establish the spin valve’s flow ca lculation model and micro-displacement double-acting hydraulic cylinder theoretical model. In o rder to determine the area parameters in flow calculation model formula, establish a variety of v alve port area formula model. Combined with the flow model of the spin valve and the cylinder theoretical model, I built the exciter model. At the same time, establishment steady-state and tra nsient flow force calculation model, and research between different parameters of the exciter an d flow force.4. Built electro-hydraulic shaker test table and validate hydraulic shock exciter theoretical m odel and flow force model.