| Ultrasonic powder-feeding device feeds powders using the attenuatingtraveling waves generated by ultrasonic vibration on the wall of a thin pipe.It possesses the following features: low feeding rate, simple structure,compactness in size, high-speed response, ease to control, and so on. Thedevice is very suitable for the precise feeding of small quantity of powders,and is urgently needed in the industrial fields and modern laboratories suchas chemical, food, pharmacy and metallurgical field. Therefore, it has beenwidely used in various fields. Its purpose is to realize efficiently and steadily the delivery of fewration of powder body accurately. It has probed into the field of designingand production of the supersonic powder body conveyor and thecorresponding experimental research. This paper consists of 6 chapters,including the research purpose and the state of arts in domestic andinternational research, the structure design of the supersonic powder bodyconveyor and its production, a brief introduction of the mechanism of thesupersonic powder body conveyor, an analysis of the vibration and responseof major transferring unit with limited elementary analysis , summary, andfuture prospect of the experimental research on supersonic powder bodyconveyor based on the weighing and control system in virtual instrument 67technology that transports rational powder body. Details are as follows: 1) In the introduction chapter, the author puts forward the purpose ofthe research. There is also a brief review of the technical background ofsupersonic powder body conveyor, summarizing the state of arts ofdomestic and international research. Finally, the author points out the majorfocus of this research. 2) The author has designed the structure of supersonic powder bodyconveyor, and has discussed the design and producing stages of conveyingunit. The mechanism of supersonic powder body has been briefly introduced.In structural design, surface smooth, heat-resisting, distortion-proof, highquality electrical plank material is chosen to make the pressing plate ofannular piezoelectricity porcelain slice; the device to prevent looseninghave been increased, and in the bottom of material cups have set analuminum system base. Experiments have shown the transport ability of thisdevice has been increased greatly. If the working condition of test prototypein transport is 13 cm for conveying section, 8 cm for material-feedingsection, 133 V in driving voltage, 58.56 kHz in working frequency, thehighest speed for transporting 60# Emery has reached to 2.98 g/s. 3) With limited first software Ansys6, finite element analysis has beencarried out of the major transporting parts of the supersonic powder bodyconveyor including annular piezoelectricity porcelain flat and transport thinpipe. Using modal analysis, the author has calculated the modal for eachstep and natural frequency of annular piezoelectricity porcelain flat andtransport thin pipe within the scope of 30-70 kHz; has calculated usingrespond analysis, the displacement response of annular piezoelectricityporcelain flat in alternating voltage that encourages any point of internaldiameter. Under radial flexible mould form, natural frequency responds forthe displacement has reached to the biggest value of 49.969 kHz. Usingrespond analysis, the author has also calculated the frequency property 68curve with the frequency scope from 49.9 to 51 kHz, step length of 100 Hz,when the transport thin pipe exerts the encouragement of 2μm periodicitydisplacement in the outside wall of one end. The farther away the transportthin pipe outside wall point from to the point of encouragement, the less thedisplacement respond amplitude. This conclusion is consistent with themechanism of ultrasonic traveling wave forming the attenuating travelingwave in transporting thin pipe when transmitting. The...
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