毕业设计（论文）-简易疲劳试验机的设计.doc

简易疲劳试验机的设计 DESIGN OF SIMPLE FATIGUE TESTING MACHINE PAGE PAGE 1 摘要 本文主要介绍了疲劳试验机的研究历史及发展现状，并针对当前疲劳试验机发展所存在的一些问题，设计一款简易弯曲疲劳试验机。试验机主要包括机械系统和测控系统。疲劳试验机的机械系统部分，主体采用曲柄滑块机构，并简单设计了试验机的试件。本课题主要设计一款简支梁式的弯曲疲劳试验机，可进行平面弯曲试验中的三点弯曲试验。综合考虑各种因素的影响，重点设计了转轴、偏心轮机构、驱动杆、夹具、机架等主要机构，为避免试验时可能发生的意外，为试验机设计了一款安全装置。本试验机的测控系统主要包括电气控制系统和测试系统。电气控制系统采用变频器实现对交流电机的转速控制；测试系统主要包括交变载荷检测系统和循环次数检测系统。交变载荷检测系统，采用电阻应变式传感器对载荷进行检测，经由放大电路以及数模转换器处理后，通过单片机进行控制显示。循环次数检测系统，通过接近开关感应信号，并由单片机控制计数及显示。 关键词 疲劳试验机；三点弯曲；变频器；载荷检测 Abstract This paper mainly introduces the research history and development status of fatigue testing machine, and designs a simple bending fatigue testing machine for some problems existing in the development of fatigue testing machine. The testing machine mainly includes mechanical system and measurement and control system. Fatigue testing machine part of the mechanical system, the main body with a crank slider mechanism, and a simple design of the test machine test pieces. The main design of a simple beam-type bending fatigue testing machine, can be carried out in the plane bending test of the three-point bending test. Considering the influence of various factors, the key institutions such as rotating shaft, eccentric wheel mechanism, driving rod, fixture and frame are designed. In order to avoid accidents that may occur during the test, a safety device is designed for the testing machine. The testing and control system of the test machine mainly includes electrical control system and test system. The electric control system adopts the frequency converter to realize the rotational speed control of the AC motor. The test system mainly includes the alternating load detection system and the cycle number detection system. Alternating load detection system, the use of resistance strain sensor to detect the load, through the amplifier circuit and digital-analog converter processing, through the micro-controller to control the display. Cycle number detection system, through the pro