共查询到20条相似文献,搜索用时 46 毫秒
1.
针对在小振幅、高频受力工况下微小与硬脆材料构件的疲劳检测,提出利用压电振子(PZT、PLZT或PMN)作为高频疲劳试验机构的驱动力源,并利用系统共振方法设计高频疲劳试验机构.首先,介绍压电共振式疲劳试验机构的工作原理,建立了动力学模型,获得了系统的动态特性.然后,设计和制作了样机.最后,利用样机测量了作用在试件上的动载荷.实验结果表明;改变输入交流电压幅值(100~250 V)和板弹簧厚度(1.1~0.6 mm),可施加在试件上的动载荷为24.7~99.2 N.本文制成的样机适用于测试动载荷在为24.7~99.2 N,且在小振幅、高频受力工况下试件的拉伸和弯曲疲劳性能. 相似文献
2.
3.
4.
5.
6.
考虑压电振子的疲劳寿命与压电泵的使用寿命有关,本文对其疲劳寿命进行了分析研究.首先,对锆钛酸铅(PZT)陶瓷(文中使用PZT-5)在力电耦合场作用下发生疲劳破坏时的极限应力与循环次数之间的对应关系进行了数值测定,借助变异系数对所选子样个数的合理性进行了判别和修正.然后,经数据处理,得到置信度为95%、存活率为99.9%时PZT的安全寿命,p-S-N双对数曲线及其对应的线性回归方程,为压电振子的疲劳寿命计算提供了必要的数据基础.最后,利用ansys和miner疲劳损伤累积假说对某共振型气体压电泵用压电振子的疲劳寿命进行计算,结果显示其为4461 h,此时的安全系数为1.25.得到的结果完善了共振型气体压电泵的技术参数,该疲劳曲线和计算方法也可应用到其它泵用PZT-5压电振子的疲劳寿命计算. 相似文献
7.
8.
光波导封装等领域对拥有大行程、高精度以及高分辨率的微位移平台有大量需求,在研究微位移平台的过程中设计了一种双铰链导向式非共振压电直线电机。简述了电机的工作原理,完成了电机的结构设计,制作出电机的样机并完成相关的实验,实验设备主要有信号发生器、功率放大器、示波器和激光位移传感器等。实验表明,电机最大速度达到10.36mm/s,分辨率达到0.3μm,理论最大输出推力达到8.33N,电机设计达到预期目的。 相似文献
9.
杨伟明 《机械工业标准化与质量》2008,(10):42-44
气门弹簧在发动机高速运行时产生的共振现象,有的是可以通过参数设计和机构设计克服的,但有的是无法避免的,本文介绍了通过气门弹簧的制造工艺手段,有效地缓冲了设计上无法避免的共振现象,减少了气门弹簧断裂现象的发生。 相似文献
10.
11.
12.
由于自吸性差、对气泡敏感等原因,单腔体压电泵在应用中受到限制,而多腔体结构是提高压电泵性能的有效途径.通过分析腔体容积与压力变化过程得出:双腔体串联压电泵只能采用串联驱动方式而不能采用并联驱动方式,双腔体并联压电泵只能采用并联驱动方式而不能采用串联驱动方式.制作双腔串联、并联压电泵样机并进行测试可以得出:串联压电泵在驱动电压200 V,频率152 Hz时,输出流量达到最大为1 150 ml/min;并联泵在压电驱动电压140 V,频率220 Hz时,输出流量达到最大为640 ml/min;因此多腔泵采用腔体串联结构能提高压电泵的工作效率,提高泵的工作性能. 相似文献
13.
14.
压电振子及流体对泵近场噪声的影响 总被引:2,自引:4,他引:2
研究了压电振子的弯曲振动形变及振动辐射噪声.首先建立压电泵压电振子振动方程,导出弯曲振动形变函数;提出用微平面活塞振动理论简化压电振子振动模型,推导了近场声压理论计算方程及泵内流体对泵噪声贡献量方程;最后把理论计算结果与试验结果进行比较分析,分别得出在不同频率下压电振子及泵内流体对泵噪声贡献的大小.在输入频率为50 Hz时,泵噪声的理论值为45 dB,实际值为37 dB,泵内流体对泵噪声的影响较大,实际值与理论值的相对误差为21.6%;在输入频率为120 Hz时,泵噪声的理论值为61 dB,实际值为62 dB,泵内流体对泵噪声的影响较小,实际值与理论值的相对误差为1.6%,证明了本研究所提出理论的正确性. 相似文献
15.
Theoretical analysis and experimental investigation of valveless piezoelectric pump with unsymmetrical ridges 总被引:2,自引:0,他引:2
Zhang Jianhui Lu Jizhuang Xia Qixiao Li Hong 《Frontiers of Mechanical Engineering in China》2007,2(1):13-19
A novel valveless piezoelectric pump with unsymmetrical ridges is presented at first. It ingeniously utilizes the inner space
of its chamber by developing its chamber bottom into unsymmetrical ridges along the direction of the inlet and outlet of the
pump. Hence, a series of cuneiform channels are asymmetrically and alternately formed between the unsymmetrical ridges and
the piezoelectric vibrator, which enables the pump to form a one-way flow instead of the function of the traditional diffuse
or nozzle elements fitted outside the chamber. Then, by analyzing the vibration of the piezoelectric vibrator, the vibration
deformation function and the equation of volume change are established. Meanwhile, the theoretical equation of the pump flow
rate is established. Finally, a real valveless piezoelectric pump with unsymmetrical ridges is manufactured, and the flow
rate of the pump is measured through experiments. It is proved that the theory is rational and correct by comparing the experimental
flow rate and the theoretical flow rate. In addition, for calculating the theoretical flow rate, the positive and converse
flow resistance coefficients of unsymmetrical ridges are measured through experiments, when one slope angle of the unsymmetrical
ridges is 90° and another is changing from 20° to 60°, respectively. 相似文献
16.
Fang YE Shouyin WANG Wei CHENG Qixiao XIA Jianhui ZHANG 《Frontiers of Mechanical Engineering》2009,4(4):420
According to the present classification method for a piezoelectric pump, this paper reviews the development and present situation of piezoelectric pumps in the latest 30 years and finally puts forward a new classification. A volumetric piezoelectric pump, which belongs to traditional volumetric pumps, can be divided into a piezoelectric pump with or without valves. A new valveless piezoelectric pump nowadays becomes a hot issue in scientific research. It is constructed by using no-moving-part valves, which can induce positive flow resistance and negative flow resistance different, and in which the inlet and outlet are connected all the time. New forms of piezoelectric pumps, different from traditional ones, are only at the stage of conception and principle, and no practical application has been reported. 相似文献
17.
Zhang Jian-hui Xia Qi-xiao Bai Heng-jun Ning Hong-gang Onuki Akiyoshi 《Frontiers of Mechanical Engineering in China》2006,1(4):429-433
The volume valve piezoelectric pump has received increasing attention from many areas because of its different characteristics
such as the absence of chemical pollution and electromagnetic pollution. However, when the pump is working, it produces cavitations
and the air bubbles that originate from these will flow out of the pump. Cavitations occurring in the pump will bring out
noise and shorten the life of the pump. Furthermore, air bubbles flowing out of the pump will hinder its application in areas
such as medical treatment and health care where blood transfusion and infusion are concerned. As a solution to this disadvantage,
the CR3DMS (cavitations resistance with 3-dimensional mesh structure) method is developed, which is tested and verified to
be effective on not only reducing the occurrence of cavitations and eliminating cavitations’ flowing out, but also restraining
the emission of noise. In conclusion, the pump with CR3DMS, on the relationship between flow and driving frequency and the
relationship between flow and the number of Resistant-Layers in both theory and test, are analyzed.
__________
Translated from Chinese Journal of Mechanical Engineering, 2006, 42(5) (in Chinese) 相似文献
18.
为了提高压电泵的工作效率,提出了对压电泵中的动力元件-压电振子进行特殊绝缘处理,使压电振子在两个方向弯曲变形时都可以形成输出工作能力,即双面作用的绝缘压电振子。阐述了由一个绝缘压电振子形成两个工作腔体的双作用压电泵结构。根据小挠度弹性弯曲理论导出了绝缘圆形复合压电振子的弹性曲面微分方程,阐述了绝缘处理方案和过程,并对其绝缘特性进行分析。对绝缘压电振子进行了实验测试,实验结果表明:双作用绝缘压电振子不仅具有绝缘特性,而且具有良好的韧性和强度;其击穿电压比未绝缘处理压电振子的击穿电压提高了20~30V。为相关产品开发和科研提供了一种新型双面作用的压电驱动元件。 相似文献
19.
Jianhui ZHANG Xiaosheng CHEN Zhenlin CHEN Jietao DAI Fan ZHANG Mingdong MA Yuxuan HUO Zhenzhen GUI 《Frontiers of Mechanical Engineering》2022,17(3):29
Existing valveless piezoelectric pumps are mostly based on the flow resistance mechanism to generate unidirectional fluid pumping, resulting in inefficient energy conversion because the majority of mechanical energy is consumed in terms of parasitic loss. In this paper, a novel tube structure composed of a Y-shaped tube and a ȹ-shaped tube was proposed considering theory of jet inertia and vortex dissipation for the first time to improve energy efficiency. After verifying its feasibility through the flow field simulation, the proposed tubes were integrated into a piezo-driven chamber, and a novel valveless piezoelectric pump with the function of rectification (NVPPFR) was reported. Unlike previous pumps, the reported pump directed the reflux fluid to another flow channel different from the pumping fluid, thus improving pumping efficiency. Then, mathematical modeling was established, including the kinetic analysis of vibrator, flow loss analysis of fluid, and pumping efficiency. Eventually, experiments were designed, and results showed that NVPPFR had the function of rectification and net pumping effect. The maximum flow rate reached 6.89 mL/min, and the pumping efficiency was up to 27%. The development of NVPPFR compensated for the inefficiency of traditional valveless piezoelectric pumps, broadening the application prospect in biomedicine and biology fields. 相似文献