【作者】 田丰君；

【导师】 杨志刚；

【作者基本信息】 吉林大学 ， 机械设计及理论， 2004， 硕士

【摘要】 研究证实，超声振动可以减小接触表面间的摩擦，不仅如此，超声波振动表面所具有的声悬浮与动压润滑能力，也已被研究证实并获得了实际应用。近年来，超声波技术的发展及其与压电技术的相结合不断地开辟出新的应用领域。以超声振动利用为特征的压电超声技术得到快速发展，超声波的生成与转换变得容易且结构简单，正是在这一基础之上，本研究课题旨在利用超声波振动来构造一种新型的轴承——超声波悬浮轴承，这也是对超声振动具有悬浮能力在应用领域中新的探索。本文对利用超声振动构造悬浮轴承的可行性进行了分析论证，以螺栓紧固型压电换能器（又称作郎之万振子）作为产生超声振动的轴承部分，设计制做了超声波悬浮推力轴承的基本结构。并且对所制做的超声波推力轴承进行了较为系统的实验研究。全文共分五章，内容如下：一、绪论超声波技术随着压电材料的出现与发展逐渐受到人们的关注，并因而迅速发展成为一门新的学科——超声学。超声波的振动频率一般高于20千赫，少数频率低于20千赫的声波的应用也包括在超声学的研究范围之内。该部分重点阐述了在超声振动下的减摩与悬浮技术，并对以螺栓紧固型压电换能器为基体，利用超声振动来构造轴承作了可行性的分析，最后概述了本文所研究的主要内容。二、压电振子基础理论问题分析本章从最基本的压电理论入手，系统地阐述关于压电效应、压电陶瓷、压<WP=60>电方程的建立以及压电振子等相关知识。 压电效应与逆压电效应反应了晶体的弹性性能与介电性能之间的耦合，这是一切压电驱动的基础。压电陶瓷材料本身硬且脆，在外电场作用下所能产生的位移或力非常小。因此，一般情况不把压电陶瓷本身作为压电振子直接应用，而是把压电陶瓷与某种弹性材料（一般为金属）固连在一起构成复合压电振子。本文所研究用于构造轴承的压电换能器便是这一类振子。压电振子起着将电能转化成振动能的核心作用，螺栓紧固型压电振子作为压电换能器的一种结构形式，是由压电陶瓷部分和与之相固连的金属部分组成。压电陶瓷材料的性能参数是设计、制造螺栓紧固型压电换能器时选择压电陶瓷片的主要依据。三、螺栓紧固型压电换能器的设计通过对压电换能器基础理论的阐述，进一步从本质上认识其工作原理。同时，对压电换能器能够实现超声悬浮的机理作出分析。之后，结合本课题的研究，对螺栓紧固型压电振子作了深入的分析并且完成了适合于构造轴承用压电换能器的设计制做。在设计制做过程中分析影响压电换能器工作性能的具体原因，力求找到换能器的最佳工作状态或方式，以设计出更趋于合理的压电振子结构。同时也为超声波径向轴承用压电换能器的设计打下一个基础。 对所设计制做的螺栓紧固型压电换能器进行了性能测试，并作出分析。四、超声波推力轴承的结构设计及实验研究在对超声波悬浮轴承的特点作出充分的分析之后，提出了悬浮轴承的设计思想，设计并制做了超声波推力轴承的基本结构。通过实验证明了所设计制做的轴承结构是合理的，能够在一定的承载下实现稳定运转。完成了超声压电换能器作为轴承所具有的悬浮能力及其悬浮间隙的基础测试，得出了悬浮间隙与载荷以及与压电换能器的振动频率、输出功率之间的关系；完成了对超声波轴承基本性能的测试：一是定性测量，通过测试所构造轴承传动系统在工作时的转速，比较了在同等条件下，超声波悬浮推力轴承、推力球轴承以及非液体润滑的滑动轴承三者的工作性能。二是定量测试，通过一定的测试方法测得了超声波悬浮推力轴承在一定载荷下轴与轴承之间产生的动摩擦力矩。 <WP=61>在实验研究的基础上，得出了相应的结论，即在超声波推力轴承的承载能力范围内，超声波悬浮轴承的减摩性能要优于同等条件下的推力球轴承以及非液体润滑的滑动轴承。五、结论与研究前景给出了全文的研究结论，并对超声波轴承进一步的研究方向提出了设想。更多还原

【Abstract】 Experiments indicate that ultrasonic vibration can minish the friction between contacted surfaces. The acoustic levitation and dynamical pressure lubricating ability of ultrasonic vibrating surfaces is proved through investigation, and practical application of the ability is achieved too. In recent years, the development of ultrasonic technology and combine with piezoelectric technology break new application fields continuously. With instant development of piezoelectric and ultrasonic technology, especially the use of ultrasonic vibration, ultrasonic generation and conversion becomes easier, and the construction becomes simpler. In this paper, a new type bearing-ultrasonic suspension bearing is constituted. And this is the new exploration of ultrasonic vibrating suspension ability in the application field. In this paper, the feasibility using the ultrasonic vibration to construct suspension bearing is analyzed, the bolt fixing piezoelectric transducer works as the bearing to generate ultrasonic vibration. Basic configuration of the ultrasonic suspension thrust bearing is designed and fabricated. And the experiment of the new fabricated thrust bearing is executed. The article consists of five parts show as followed:1. IntroductionAlong with the development of piezoelectricity material, ultrasonic technologies get more attention and develop to a new subject-ultrasonics. Generally, the ultrasonic vibration frequency is above 20 KHz, the application of few sound wave which frequency under 20 KHz is also including the research of ultrasonics. In this part, the antifriction and suspension technology in the case of ultrasonic vibration is expatiated, and bolt fixing piezoelectric transducer is constructed as the basal body, the feasibility of bearing construction using ultrasonic vibration is <WP=63>analyzed, in the last of this part, the main contents studied in the paper is given.2. Analysis on piezoelectric vibrator basic theoryThis chapter introduces the basic theories of piezoelectricity as well as piezoelectric phenomena，ceramic, equations and piezoelectric vibrator.Piezoelectric effect and contradictorily piezoelectric effect reflect the coupling of the elastic property and dielectric property; it is the base of all piezoelectric driving.In general, piezoelectric material fixed with some elasticity material to form the vibrating body, and it is called the complex piezoelectric vibrator. The bolt fixing piezoelectric vibrator is made of piezoelectric ceramic part and metal part. During designing and fabricating of the bolt fixing piezoelectric transducer, the performance of the piezoelectric ceramic material is the main basis to select the piezoelectric ceramic.3. Design of bolt fixing piezoelectric transducer Along with studying of the basic theory, operational principle of piezoelectric transducer is understood in essence. And the ultrasonic suspension mechanism of the piezoelectric transducer is analyzed. In this paper, the bolt fixing piezoelectric vibrator is investigated thoroughly and the piezoelectric transducer fitting for constructing bearing is designed and fabricated. The specific reasons effecting the working performance of the piezoelectric transducer are analyzed to find the optimal operating state and method, and then the more reasonable piezoelectric vibrator is designed. All works here lay a foundation for the design of piezoelectric transducer used in the ultrasonic radial bearing. The performance testing of the bolt fixing piezoelectric transducer is performed, and related analysis is executed.4. Structural design and experimental study of the ultrasonic thrust bearing After the sufficient analysis of the ultrasonic suspension bearing, design philosophy of the suspension bearing is put forward, and the basic structure of ultrasonic thrust bearing is designed and fabricated.Experimental study of ultrasonic bearing consists of two parts, one part is <WP=64>observational measurement, rotate speed of the bearing drive system is tested. And at equal conditions, the wo更多还原