【作者】 胡随平；

【导师】 杨士敏；

【作者基本信息】 长安大学 ， 机械电子工程， 2008， 硕士

【摘要】 推土机通过铲刀与外界作业介质(如土壤、砂石等)发生相互作用,从而完成各种作业工况。推土机铲刀与土壤相互作用过程及其机理的研究是设计和使用推土机的基础。推土机铲刀与土壤相互作用理论是工程机械地面力学中工程机械工作装置与工作介质相互作用理论的重要研究内容。推土机铲刀与土壤相互作用试验研究的方法通常包括整机现场试验和模型铲刀室内土槽试验。整机现场试验主要受到作业环境限制,试验条件难以保证。模型铲刀室内土槽试验除需要一定规格的土槽和牵引台车外,由于采用模型铲刀,试验结果未能完全反映原型铲刀与土壤相互作用的过程和机理。综合分析上述两种方法的优缺点,本论文依托长安大学工程机械多功能综合试验台,构建了原型铲刀室内土槽试验研究系统。该试验系统包括铲刀牵引系统、铲刀切深控制系统、传感器和试验数据采集与处理系统等,各子系统构成一个有机体,可以较好满足推土机铲刀与土壤相互作用研究的基本需要。推土机铲刀与土壤相互作用试验研究中测量铲刀推土阻力是一项重要内容。本论文采用在工程机械试验研究中广泛应用的八角环测力传感器来测取铲刀推土阻力。根据试验要求,布置了八角环测力传感器在试验台车上的位置。在分析各八角环受力状态的基础上,研制了满足试验要求的八角环测力传感器,并进行了传感器性能标定。标定结果显示,所研制的八角环性能良好。本论文进行了四种推土机铲刀与土壤相互作用试验方法研究,包括推土机铲刀推土阻力试验、单位切削阻力试验、振动切土试验和减粘降阻试验等。在推土机铲刀推土阻力试验中,给出了试验总体方案,确定了试验条件,组建了测试系统。由于推土机铲刀推土阻力时间历程具有非平稳性质,本论文讨论了此种时间历程的处理方法。在单位切削阻力试验中,由于影响因素较多,采用了正交试验法。在振动切土试验中,给出振动切土功率消耗试验研究方法。在铲刀减粘降阻试验中,根据减粘降阻机理,提出了几种试验方案。本论文构建的试验系统和提出的试验方法为今后全面地进行推土机铲刀与土壤相互作用研究提供了有价值的参考。更多还原

【Abstract】 Bulldozer completes each kind of operations by soil-blade interaction. It is significant to study the soil-blade interaction process and mechanics in researching the performance, design and utilization of bulldozers. The soil-blade interaction theory is the important research content of mutually affects of the constructing machinery’s work devices and work medium in the constructing machinery terramechanics and travel theory.The test methods of soil-blade interaction have usually two kinds: field test and model blade indoor soil bin test. The field test is mainly restricted by the work environment, and the test conditions are difficult to be guaranteed. The model blade indoor soil bin test needs certain specification soil bin and hauling vehicle. Because of using model blade in the soil bin test, the test results can not reflect completely the process and mechanics of soil-blade interaction. Compared with the two test methods above-mentioned, this paper has constructed a bulldozer blade indoor soil bin test research system based on the constructing machinery multi-function test platform of Chang’an University.This bulldozer blade indoor soil bin test research system consists of blade hauling system, blade cutting depth control system, sensors and data gathering and processing system and so on. Various subsystems constitute an organism, it can well meet the primary needs of bulldozer blade indoor soil bin test research.The bulldozer blade work resistance measurement is the important research content in the soil-blade interaction test. In this paper, octagonal ring dynamometers are used to sense the bulldozer blade work resistance, which are widely applied in the constructing machinery test research. According to the test requests, octagonal ring dynamometers are arranged on the correct position of the constructing machinery multi-function test platform. The octagonal ring dynamometers have been designed under the analysis of stressful condition of each one and have been calibrated later. The calibration result indicates that the performances of the octagonal ring dynamometers are high.This paper studies four kinds of test methods of the soil-blade interaction for bulldozer: indoor soil bin test method of bulldozer blade work resistance, unit cutting resistance test method, vibratory soil cutting test method and adhesion reducing test method. In the first kind, the test method and conditions have been given, and the measurement system has been set up. Because the bulldozer blade work resistance time history records are non stationary, this paper discusses the processing method of which. In the second kind, orthogonal test design has been used in the consideration of the large interaction elements related to cutting resistance. In the third kind, the test method of power consumption in vibratory soil cutting has been given. In the last kind, according to the mechanics of adhesion reducing of the blade, some valuable test schemes have been given.The test system and test method in this paper provide some valuable references for the future overall soil-blade interaction research.更多还原