Research On Suspension Piezoelectric Inertial Resonant Diaphragm Pump

This dissertation is funded by the National Natural Science Foundation “piezoelectric fluid inertial actuator basic theory and key technology research”, the project number is51205369, it is based on the resonance principle, by adjusting the frequency, voltage to achieve precision control of the diaphragm pump, recently it has been more widely used in the field of drug delivery, fuel supply, chemical analysis and detection. Although the diaphragm pump was widely used in industry fields, but special applications put forward higher standard to piezoelectric diaphragm pump’s dimensions and output performance. there are two main type of diaphragm pump,include electromagnetic diaphragm pump and piezoelectric pump,they have their own advantages and disadvantages, applications has been limited in the market.At present, in the research of piezoelectric resonant diaphragm pump, for application is lack of intermediate fixed support structure of piezoelectric vibrator, therefore this dissertation propose combined with the intermediate fixed support structure of piezoelectric vibrator and system resonance technology, developed a new type of the piezoelectric resonant diaphragm pump, it is the use of the piezoelectric vibrator of two free end suspension inertial to incentive system resonance.The research contents are as follows:1. the research status of the domestic piezoelectric resonance pump are analyzed, This dissertation also analysis the basic knowledge of piezoelectric materials, piezoelectric vibrator as the main driving component of piezoelectric resonance pump, the basic structure and vibration mode are analyzed, and list the three main support ways of the piezoelectric vibrator.the rectangular piezoelectric vibrator of the intermediate fixed support are actuated by the sine wave, The experimental results, the free end deformations of the rectangular piezoelectric vibrator under different voltage, relationship between displacement and frequency of the free end rectangular piezoelectric vibrator, selected reasonable driving signal and frequency range,so that the piezoelectric vibrator stably work.2. analyze the connection mode of a rectangular piezoelectric vibrator, according to the three main support ways of the piezoelectric vibrator, and the dynamic characteristics of three main ways of support rectangular piezoelectric vibrator simulation analyze, its first four order natural frequency and modal shape of three main ways of support rectangular piezoelectric vibrator were analyzed by using COMSOL, study on the static characteristics of the intermediate fixed support piezoelectric vibrator was analyzed using MATLAB software,analysis of the structure size parameters on the dynamic deflection and free ends impact the effect of amplitude. Then, the amplitude test test platform was built, by test get the amplitudechanges with distance of the rectangular piezoelectric vibrator of three main ways of support,also use the precision impedance analyzer the resonance frequency of the piezoelectric vibrator of the intermediate fixed support, and selected the suitable structure size of the piezoelectric vibrator.3. analyze the structure design and working process on suspension piezoelectric inertial resonant diaphragm pump, the internal structure of the vibration unit are analyzed, start with the resonance principle of vibration unit, establishs a dynamic model of the vibration unit,gets a key factor to affect the displacement of the vibration unit, calculates the stiffness of the main internal structure. Then, uses precision impedance analyzer the resonant frequency of the resonant pump, the additional mass is optimized by repeatly detect, the results show that with the increase of the mass of the additional mass, the resonance frequency of the resonant pump decreases. In addition, uses laser micrometer to measure the displacement of the diaphragm and the piezoelectric vibrator, get the vibration unit displacement of magnification.Further illustrate that, compared with the conventional piezoelectric pumps in general, has obvious advantage in output performance.4. it is mainly to taking the suspension piezoelectric inertial resonant diaphragm pump pumping unit and output performance as the research objects. In the first part, describes the internal structure and working mechanism of the pumping unit. Analysis of the diaphragm deflection, the diaphragm is optimized, and the influence between volume rate of change of the pump chamber and bubble and lag valve the resonance pump output performance were analyzed and explained. The second part is aimed at the experimental test bench for output flow and output pressure was built, selected the best appropriate cut-off valve, and analyzed the influence of the diameter of the valve plug on resonance pump output performance, In the case of the valve plug diameter was determined, By selecting valve holes of different diameter,height different cavity, lengths of different the vibration rod, resonance pump output performance was tested. The results showed that: in the best resonant frequency, compared with other resonance pump, although the output flow was not very obvious, but the output pressure is very great.