共查询到19条相似文献,搜索用时 171 毫秒
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径向-扭转振动复合型超声波电机的理论与实验研究 总被引:1,自引:1,他引:0
纵扭复合型超声波电机比其他超声波电机更具低速大力矩的特点,可以直接驱动负载,适合航空航天领域的应用.不过由于纵、扭振动在定子中的传播速度不一样,其纵、扭两相谐振频率的调谐一直是个难题.提出一种新型的中空结构的径向-扭转振动复合型超声波电机,采用一对纵振压电陶瓷和一对扭振压电陶瓷的组合方式,利用了径向一阶振动模态和扭振一阶振动模态,并通过电机定子的中空结构和尺寸的调整,使径向和扭转两相基频一致.首先从理论上分析了此方案的可行性,即提出了两相调谐的方法,并对以前的模型加以改进,然后根据理论分析制作了Φ60 mm的样机,经过试验,发现其性能满足设计要求,样机的最高转速为40 r/min,堵转力矩为3.2 N·m.研制的超声波电机较其他电机具有轴向尺寸小和重量轻等特点,可以减小质量40%. 相似文献
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纵-扭复合超声振动加工系统设计及频率简并研究 总被引:1,自引:0,他引:1
纵-扭复合超声振动加工技术在硬脆性材料的加工中受到越来越多的重视,针对该种需求,设计了一种纵-扭复合超声振动加工系统,基于有限元方法对该类系统普遍存在的频率简并问题进行了研究。利用数值解析方法设计出超声换能器和超声变幅杆,之后在变幅杆上做出螺旋槽,一部分纵向振动转换为扭转振动;以目标频率附近的纵、扭谐振频率尽量接近为原则,利用有限元软件分析系统的结构参数对纵、扭谐振频率的影响规律,实现频率简并;在此基础上对系统进行模态分析和瞬态动力学分析,结果表明系统可以实现纵-扭复合超声振动,验证了此种频率简并方法的有效性和实用性。 相似文献
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F4超声驻波马达耦合振子研究彭军宇,周铁英(清华大学物理系北京·100084)1985年Kumada提出一种纵弯扭耦合超声驻波马达,该马达定子是由一个单梁纵弯扭耦合振子及与其相匹配的朗之万型换能器组成,文章没给计算方法。1993年我们用有限元方法计算... 相似文献
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针对引进型大型发电机定子绕组端部振动超标问题,提出一种基于温度场变化的定子绕组端部振动主动调频控制方法。采用两端固定-铰支直梁,研究温度场变化对结构固有频率的影响机制。据此设计试验方案,结果表明,通过调整定子冷却水、冷氢温度,达到定子绕组端部固有频率远离电磁激振频率的目的,避开了共振区,从而有效地降低了定子绕组端部的振动。最后,开发了基于温度场热应力主动调频控制逻辑模块,为控制汽轮发电机定子绕组端部的振动提供一种新方法。 相似文献
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介绍一种圆盘型非接触超声波马达的结构。利用有限元法计算了超声波马达定子在不同振动模态下的固有频率,并用激光测振仪对定子进行了测试,结果两者吻合较好。由于振幅和非接触马达的声辐射压力密切相关,因此通过谐响应分析计算了定子的振幅与定子驱动电压的关系,从而为马达的实验研究提供了理论依据。在最优模态B21下进行转子转速测试,测得最高转速为1600rpm。 相似文献
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采用DK-Ⅱ型扭振测量系统,进行了不同转速下不平衡转子的弯曲,扭转振动的联合测量,得到了存在不平衡的故障转子的扭振特征和变化规律,即当转动频率小于一阶扭振固有频率时,扭振幅值随转速的升高而增大;当转动频率大于一阶扭振固有频率时,扭振幅值随转速的高而减小;当通过扭振界转速时,扭振相位翻转180°。 相似文献
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《振动与冲击》2016,(22)
提出一种新型贴片式纵扭压电电机,包含定子,转子和预压力系统等。电机定子经过特殊的开槽处理形成多振子结构,振子由金属基体和粘贴在其外表面的压电陶瓷构成,益于简化电机结构。通过合理的参数调整,使定子的一阶纵振模态和二阶扭转模态频率尽可能相同,并且振子均工作在共振状态,提高了电机效率。为评估设计电机的整体性能,建立了定子和转子的有限元接触模型,并对电机的接触特性进行分析研究。通过接触静态和瞬态求解,得到空载情况下接触区的压力分布、接触状态及滑动距离等参数,同时得到电机的转速变化曲线和输出性能等。分析结果表明该纵扭电机为多面接触,接触压力不存在局部高度集中的情况,且接触区域存在滑动。最后,根据设计的电机参数,加工原理样机,对理论分析进行实验验证。 相似文献
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Sandwiched piezoelectric ultrasonic transducers oflongitudinal-torsional compound vibrational modes 总被引:1,自引:0,他引:1
Lin Shuyu 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1997,44(6):1189-1197
Sandwiched piezoelectric ultrasonic transducers of longitudinal-torsional compound vibrational modes were studied. The transducers consist of coaxially segmented, longitudinally and tangentially polarized piezoelectric ceramic rings, a back metal cylinder, and a front exponential solid metal horn. Based on the plane-wave approximation, the equivalent circuits of the longitudinal and torsional vibrations in the sandwiched transducer were obtained and the resonance frequency equations of the transducer in longitudinal and torsional vibrations were derived. By means of choosing the radius decay coefficient of the front exponential horn, the longitudinal and torsional vibrations are made to resonate at the same frequency in the transducer. Sandwiched piezoelectric ultrasonic transducers of longitudinal-torsional compound modes were designed and fabricated according to the frequency equations. It is demonstrated that the measured resonance frequencies of the transducers are in good agreement with the theoretical results, and the measured resonance frequencies of the transducers in longitudinal and torsional vibration modes are also in good agreement with each other. Theoretical and experimental results show that this kind of transducer can be used in ultrasonic welding, ultrasonic machining, ultrasonic motors, and other ultrasonic applications which need large displacement amplitudes 相似文献
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Wang Jian Guo Jifeng 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2009,56(5):1054-1058
A longitudinal-torsional hybrid-type ultrasonic motor has larger torque and lower revolution speed compared with other kinds of ultrasonic motors. It drives devices directly and precisely, so it is adaptable to many fields, especially aeronautics and astronautics, as a servo actuator. Due to the different sound propagation speeds of longitudinal and torsional vibrations in the stator, it is difficult to match resonant frequencies of longitudinal and torsional vibrations. In this paper, a new radial-torsional vibration hybrid-type ultrasonic motor is put forward, which utilizes longitudinal vibration derived from radial vibration by the Poisson effect. The short, hollow cylindrical structure easily makes resonant frequencies of first-order radial and torsional vibrations into degeneracy. First, the new structure of the motor is presented. Second, the principle of matching the resonant frequencies is developed, and the motor geometry is optimized by ANSYS software. Finally, a 60-mm diameter prototype is fabricated, which performs well. The no-load velocity and maximum torque are 25 r/min and 5 N·m, respectively. This kind of motor is small, light, and noiseless. 相似文献
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Piezoelectric ultrasonic motor using longitudinal-torsional composite resonance vibration 总被引:2,自引:0,他引:2
Ohnishi O Myohga O Uchikawa T Tamegai M Inoue T Takahashi S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1993,40(6):687-693
A piezoelectric ultrasonic motor, which uses longitudinal and torsional composite vibration, is examined in order to obtain high torque characteristics with small diameter. Piezoelectric ceramic elements, oscillating in both longitudinal and torsional modes, respectively, are used as piezoelectric stiffened modes having high electromechanical coupling factors k(33) and k(15), respectively. It is found that the resonant frequencies for longitudinal mode and torsional mode could coincide with each other in the ultrasonic motor, according to finite element method analysis and experimental measurement. The motor operating in both resonant vibrations indicated good performance. The 20-mm diameter motor exhibited 4 kgfcm maximum torque, 450 r/min maximum rotational speed, 40% maximum efficiency, and quick responsiveness, within 2.5 ms. 相似文献
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电刷式纵扭型超声电机结构设计中的关键技术 总被引:1,自引:0,他引:1
详细阐述了在电刷式纵扭型超声电机设计中所遇到的三个关键技术:电机结构型式的选择、纵、扭模态频率一致性和压电陶瓷的安装位置的合理性。分别论证了这些技术的关键所在以及作者提出解决的办法。据此,设计和制造了一台纵扭型超声电机原型机,并获得了较为满意的整机性能。 相似文献
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Satonobu J. Friend J.R. Nakamura K. Ueha S. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2001,48(6):1625-1631
In this paper, operation of a symmetric hybrid transducer ultrasonic motor with output produced by two rotors connected together via a drive shaft is numerically analyzed and compared with the traditional asymmetric hybrid transducer motor design that produces its output from only one rotor. A one-dimensional finite element model for torsional vibration in the stator and a Coulomb friction model for rotor/stator contact associated with the longitudinal vibration of the motor are introduced. The calculation results demonstrate that the symmetric design is capable of performance comparable with the traditional asymmetric design when an optimum static spring force in the rotor/stator contact interface is applied during operation 相似文献
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Improvement of the longitudinal vibration system for the hybrid transducer ultrasonic motor 总被引:3,自引:0,他引:3
Satonobu J Lee D Nakamura K Ueha S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2000,47(1):216-221
This paper presents a symmetric hybrid transducer ultrasonic motor designed to produce large longitudinal vibration stress in the rotor/stator contact interface for high-torque operation. The nodal plane of the longitudinal vibration mode was adjusted to match the rotor/stator contact interface, and the piezoelectric ceramic disks for the longitudinal vibration were installed at the nodal plane of the longitudinal vibration mode for effective excitation. An experimental motor, 20 mm in diameter, using the first torsional vibration mode and the second longitudinal vibration mode was manufactured. A maximum torque of 0.8 N.m was achieved in the prototype, an improvement over previous versions. 相似文献
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阐述了单相串励电动机的工作原理,建立了对应的数学模型,推导了电磁转矩表达式。对单相串激电动机在多种工况运行下的扭转振动进行了检测,得到了电动机的负载-扭转振动特性,以及电压-扭转振动特性。对相关特性的产生机理进行了分析,根据单相串励电动机的转矩表达式和转矩平衡方程得到了相应的结论,为单相串励电动机扭转振动的抑制提供了技术支撑。 相似文献
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钻柱纵向和扭转振动分析 总被引:18,自引:0,他引:18
介绍钻柱的振动状态和产生振动的原因。针对钻柱的纵向振动,分别建立了力激励法和位移激励法的数学模型;计算结果表明,力激励法与位移激励法求得的消振转速相反,即力激励法的消振转速恰恰是位移激励法的共振转速,反之亦然;传统多以力激励为边界条件来研究钻柱纵向振动的频率响应,并指导现场消振作业的,这样给出的最佳消振转速,恰恰是共振转速;在钻井作业中,钻头的纵向跳动比纵向受力的变化要稳定得多,钻柱的动负荷比动位移重要得多,应该用位移激励法研究钻柱的纵向振动问题。针对钻柱的扭转振动问题,分别建立了扭矩激励法和转角激励法的钻柱扭转振动数学模型;证明用转角激励法来研究钻柱的扭转振动更符合实际。 相似文献