Research On Non-Load Characteristics Of Hydraulic Vibrator And Dynamics Of High-Frequency Excitation Valve

With the rapid development of industrial technology, the research cycle and precise requirements on products are also increasing. Not only vibrator can be used as fatigue-testing machine to shorten the research cycle, but also as the critical device of vibration cutting to solve the processing problems of the materials difficulty to cut. And the vibration frequency directly determines its performance, so it’s of great significance that research on how to improve the vibration frequency.Due to the limited frequency response characteristics of the servo valve, the vibration frequency is difficult to achieve a higher level. Therefore, switch to a three-way valve control the hydraulic exciter to achieve high-frequency vibration. The elastic cover of the flutter vibrates by the three-way valve of rotary structure to control fluid enter into hydraulic cylinder alternately. The major work and achievements of this paper are as follows:(1) Firstly, the structural composition of hydraulic exciter was analyzed, then introduced the working principle of high-frequency excitation valve and set up its mathematical models. On this basis, the characteristics equations of hydraulic exciter was established and simulated byAMESim.(2) Secondly, researched on dynamics of the high-frequency excitation valve. The friction torque equations of the spool of high-frequency excitation valve was built, and studied the transient flow force of spool at high speed rotation.(3) Thirdly, researched on non-load characteristics of the hydraulic vibrator. Set up the experimental platform, collected the variation characteristics of pressure, acceleration, displacement and flow in the vibration frequency of0.1Hz to4000Hz when system pressure was at3.35MPa and elastic cover was in different mass. Find the perfect excitation frequency and resonant frequency by analyze the waveform, and studied the influence on these characteristics brought by change of the elastic cover’s mass and excitation frequency. And then changed system pressure,studied the resonant characteristics of vibrator in different pressure. At last, compared the displacement waveforms between theoretical and practical variation in low excitation frequency. (4) The improved design of hydraulic vibrator was proposed according to the problems existed in experiment, the preparations for further study was made.