圆形电连接器跌落过程的动力学研究及可靠性设计

发布时间：2018-02-02 00:50

本文关键词： 电连接器跌落冲击动态响应参数灵敏度优化设计　出处：《江苏大学》2017年硕士论文　论文类型：学位论文

【摘要】：宇航级电连接器的工况越来越严苛,性能要求也越来越高,在运输或使用过程中需要考虑电连接器或其附件的跌落失效形式和规律。本文以YDA型圆形电连接器为研究对象,从接触碰撞的力学模型和产品对跌落冲击的响应出发,结合数值模拟和实验分析,研究了该模型在跌落过程中的冲击响应规律。主要研究结论如下:在其他工况不变的情况下,模拟分析了圆形电连接器在100mm高度下跌落撞击地面的整个冲击响应过程,研究了关键零件插针和壳体的冲击应力分布和加速度响应规律。结果表明:插针所受跌落冲击最为严重,且冲击应力集中在轴肩顶部,最大值为176.6MPa;通过跌落冲击试验,测试了电连接器壳体某一位置的冲击加速度响应,结果表明该响应峰值与模拟结果基本吻合,误差仅为2.5%,验证了跌落冲击模拟的可靠性。在跌落姿态不变的情况下改变跌落高度,分析其冲击响应随跌落高度的变化规律,结果表明随着跌落高度的增加,峰值冲击应力逐渐增大,且插针的冲击应力增速大于壳体,并在1200mm高度时率先发生塑性变形;而冲击加速度随跌落高度的增加,呈加速度趋势增长,且插针所受横向冲击加速度最为严重。在跌落高度不变的情况下改变跌落姿态,结果发现角度跌落时座壳体所受冲击应力均大于竖直跌落,且以60°角跌落时产生的峰值冲击应力最大,而发生水平跌落时插针产生的峰值应力最大;分别针对座壳体和插针的危险角度进行模拟计算,得到该圆形电连接器的临界跌落高度约为750mm。对圆形电连接器整体模型进行了模态分析,得到了前五阶固有频率,通过与实验测得的振动频率进行对比,发现在不同跌落高度下的振动频率还达不到系统的一阶固有频率,结果表明了圆形电连接器在跌落冲击过程中不会产生共振现象。研究了初步优化后其结构参数对跌落冲击响应的影响规律,通过灵敏度分析,发现插针轴肩根部圆角和轴环厚度是影响冲击应力的关键参数,并对插针的关键参数进行了尺寸优化设计,优化后该电连接器的峰值冲击应力降低了59.7%,冲击加速度降低了44.8%,结果表明该优化方案大大提高了圆形电连接器的抗跌落性能。
[Abstract]:The working conditions of aerospace grade electrical connectors are becoming more and more severe, and the performance requirements are becoming higher and higher. In the process of transportation or use, we need to consider the drop failure form and rule of electrical connector or its accessories. This paper takes YDA type circular electric connector as the research object. Based on the mechanical model of contact impact and the response of products to drop impact, numerical simulation and experimental analysis are combined. The impact response of the model in the process of falling is studied. The main conclusions are as follows: under the condition of other conditions unchanged. The whole shock response process of the circular electrical connector falling into the ground at 100mm height was simulated and analyzed. The impact stress distribution and acceleration response of the pin and shell of the key parts are studied. The results show that the drop impact of the pin is the most serious and the impact stress is concentrated on the top of the shaft shoulder. The maximum value was 176.6 MPA; Through the drop impact test, the shock acceleration response of the electric connector shell at a certain position is tested. The results show that the peak value of the response is basically consistent with the simulation result, and the error is only 2.5%. The reliability of the drop impact simulation is verified. The drop height is changed under the condition of constant drop attitude, and the change rule of the impact response with the drop height is analyzed. The results show that the drop height increases with the drop height. The peak impact stress increases gradually, and the impact stress growth rate of the pin is larger than that of the shell, and plastic deformation occurs first at the height of 1200mm. The impact acceleration increases with the drop height, and the transverse impact acceleration of the pin is the most serious. The drop attitude is changed when the drop height is constant. The results show that the impact stress of the shell is greater than that of the vertical drop, and the peak impact stress is the largest when the angle is 60 掳, and the peak stress of the pin is the biggest when the horizontal drop occurs. The critical drop height of the circular electrical connector is about 750 mm. and the whole model of the circular electrical connector is analyzed. The first five natural frequencies are obtained. By comparing with the vibration frequencies measured by experiments, it is found that the first order natural frequencies of the system can not be achieved at different drop heights. The results show that circular electrical connectors do not produce resonance during drop impact. The influence of structural parameters on drop shock response is studied after preliminary optimization and sensitivity analysis is carried out. It is found that the angle of the shaft shoulder root and the thickness of the shaft ring are the key parameters affecting the impact stress, and the key parameters of the pin are optimized. After optimization, the peak impact stress and the impact acceleration are reduced by 59.7 and 44.8 respectively. The results show that the anti-drop performance of the circular electrical connector is greatly improved by the optimized scheme.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM503.5

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