【作者】 关春光；

【导师】 杨志刚；

【作者基本信息】 吉林大学 ， 机械设计及理论， 2007， 硕士

【摘要】 本文结合国家自然科学基金项目“用于振动给料的超声波驱动理论与方法的研究(项目编号:50575088)”开展研究工作。和已有的振动给料器相比,利用超声振动实现物料的有序输送是一个全新的设想,本文根据压电及超声波驱动技术,进行了有关的理论分析和计算,设计出采用纵向振动模式的超声换能器为驱动源的新型超声振动给料方式,自制了样机,并进行了相关的实验测试与分析。论文对国内外振动给料器的发展状况进行了概述,阐述了在超声振动状态下完成物料输送、实现给料功能研究的课题背景、意义以及可行性;讨论了超声换能器的振动模态等基础技术理论,并根据相关的分析和计算,选择了纵向振动模态的螺栓紧固型压电式超声换能器;对其结构参数进行了设计计算,并且自制了用于实验的超声振动给料器样机;在对超声波振动给料方式的结构进行了分析研究的基础上,建立了系统的动力学模型,分析了其固有频率和激振频率的关系;利用ANSYS软件对换能器的纵向振动模态进行了分析,并利用阻抗分析仪测取了换能器在不同的状态下的谐振频率及阻抗的变化;通过实验,测定了换能器的端面振幅,并对给料器样机进行了初步实验,分析了系统没有达到谐振状态和实现最佳给料性能的几种原因,最后对给料器结构的优化提出了进一步的构想。超声波振动给料器的工作频率为20kHz左右,振幅一般不大于20μm,具有送料平稳、无噪声、不产生磁干扰等特点。本文是在课题组首次提出采用超声振动方式完成给料功能的概念基础上开展实验研究的。更多还原

【Abstract】 A new concept utilizing ultrasonic vibration feeding to realize the foreword transportation of the material is proposed for the first time in the paper. In this paper an ultrasonic feeder have been designed and manufactured that used the transducer as the vibration source in the example mechanism, and we carried on some experiments about it and get some conclusions.The paper consists of six chapters, given as follows:1. IntroductionAs an important link in the automatic production line and assembly line, the vibration feeder is widely applied in the light industry and other occasions. But the traditional feeders(electromagnetic and piezoelectric vibration feeder) are limited in certain degree in the clean and low noise occasions. The paper lists the advantages and disadvantages of the electromagnet and piezoelectric feeders, and then a review about the domestic and foreign research results of the two kinds of feeders is given. In this foundation, a new way that uses the ultrasonic wave to feed instead of the low tone frequency is proposed. And its feasibility and the possible broad application prospect are analyzed.2. The basic theory of PiezoelectricityThis chapter mainly introduces the basic theory of piezoelectricity, expatiates piezoelectric knowledge that related with the transducer. The basic concepts of piezoelectric effect, piezoelectric material and piezoelectric equation are introduced. Four kinds of piezoelectric equation that used to derive the vibration mode of thetransducer are listed.3. Design of bolt fixing piezoelectric transducerIn this chapter the ultrasonic technology and its application are introduced. The theory and the structure of the transducer are analyzed. The longitudinal oscillation mode ultrasonic transducer has been selected in this chapter. And bolt fastening ultrasonic transducer which can produce this mode is designed. At last the power supply that drive the transducer is introduced.4. The structure design and movement analysis of the ultrasonic feeding systemIn this chapter, the structure and the components of the ultrasonic feeding are designed and manufactured. The material movement mathematical model and the mechanics model of the vibration feeding system are established. The relation between natural frequency and vibration frequency is analyzed.5. The experimental study of the ultrasonic feeding systemIn this chapter, the transducer is tested. Its parameters such as resonance frequency and impedance are obtained by impedance analyzer. The transducer’s amplitude is surveyed and we also get the relational curve between oscillation amplitude and frequency. Moreover, through experiment we found that the resonance frequency of the transducer has changed in the different state, and the factor that influenced the frequency is analyzed. And we carry on experiments to the new feeding way. The comparison between the performance of the ultrasonic feeder and ordinary feeder is carried on. The factors that influenced the system’s resonance are analyzed.6. Conclusion and expectationIn this chapter the conclusion of the paper is given and the optimization plan of the ultrasonic feeding way is proposed, and the other structures that can realize ultrasonic feeding are assumed.更多还原