5t装载机变速箱的改进与试验研究

发布时间：2018-03-24 17:13

本文选题：装载机　切入点：变速箱　出处：《吉林大学》2011年硕士论文

【摘要】：本文结合某装载机生产企业的专项技术研究项目,以目前国内5t级装载机通常使用的ZL50行星式变速箱作为研究对象,在对其常见的故障进行分析、相关参数校核的基础上,提出和实施一些有效的改进措施,降低变速箱的故障频率、提高其可靠性、延长其使用寿命,是变速箱技术改进在装载机产品上的工程应用实例。本文进行了如下理论分析和实验研究。 1)综述了装载机变速箱现状及本课题研究的目的和内容广泛了解和借鉴国内5t级装载机产品现有的变速箱设计技术和方法。在其理论基础上,收集其常见故障模式,分析其失效因素,为设计改进提供原始素材。 2)改进型变速箱关键零部件结构优化及强度分析。结合装载机实际工作情况和工程机械实际制造情况,工作泵、转向泵、变速泵的使用和制造情况按中等情况考虑,工作泵、转向泵、变速泵花键联接的挤压应力都小于许用值;超越离合器采用变矩器失速输出的最大力矩进行接触应力计算,其余工况下均应低于此值;通过三合一螺栓联接结构、直接档轴与二档齿圈联接螺栓结构、直接档连接盘联接结构的优化设计,计算分析其强度足够;通过碟形弹簧结构的优化设计,计算分析其寿命足够;通过二档摩擦片传递扭矩的计算,显示该处摩擦片传递的扭矩足够。通过对比可知,设计理论强度、寿命等关键技术参数改进型变速箱均优于原ZL50行星式变速箱。 3)对变速箱箱体结构进行优化设计,并进行强度分析。通过一档工况下改进型变速箱箱体变形有限元分析,得到V轴轴承座位移响应曲线,且计算结果和模型位移分布与实际情况相符,证明了本文所建立的变速箱位移响应模型与计算的正确性。该箱体总体结构布局比较合理,在大应力区域严格控制铸造缺陷;改变区域的筋板分布对振动改善最好,对前输出法兰而言,其上的只是局部降低振动,建议维持原前输出法兰固定筋板布局不变,采用反变形措施,在装载机后车架增加刚性固定支架与五轴箱下环面约束考虑工艺实施方案的困难程度,兼顾成本与改进,在总体结构布局已定的情况下,为减少五轴箱前输出端漏油故障,改进薄弱处的结构和筋板分布,减少其变形是较为成熟的方向并借鉴国内外箱体密封结构特点,采用“背靠背”安装方式,采用进口油封材料,采用合理工艺装配手段。 4)变速箱试验研究根据改进后变速箱试验件的技术指标,应用变速箱试验系统对改进型变速箱样件进行空载功率损失、工作油压、换挡过程、传动效率、温升特性等性能试验和总成可靠性试验,对其性能及可靠性进行评估,并与原ZL50变速箱进行对比分析,为优化设计提出改进建议。 (1)变速箱空载功率损失偏大、效率偏低,主要原因可能是变矩器效率偏低,以及变速箱内的齿轮加工精度较低,建议适当提高齿轮件的加工精度等级,以提高效率、降低振动噪声; (2)改进型超越离合器在重载试验及带载循环可靠性试验中,运转状况良好; (3)变速箱前输出轴漏油,应加强油封及密封圈的装配质量控制; (4)其余各改进件经强化试验未见异常,建议小批量装配试用。通过广泛了解和借鉴国内外装载机变速箱制造技术,仔细分析5t装载机变速箱易出现故障件的理论机理,依据理论计算和测试分析结果,提出并且实施了积极有效的结构优化、制造过程控制。经过试验验证变速箱的各项指标均优于原ZL50行星式变速箱,达到预期效果。
[Abstract]:In this paper, combined with the special technology research project of a loader production enterprises, the current domestic 5T class loaders usually use ZL50 planetary gearbox as the research object, in carries on the analysis of the common fault, based on the related parameters of checking, propose and implement some effective improvement measures, reduce the frequency of gearbox fault. To improve its reliability, prolong the service life, is to improve the engineering application in loader products of the transmission technology. This paper follows the theoretical analysis and experimental research.
1) the present situation of the loader gearbox and the purpose and content of the research on this subject are summarized.
Widely understand and learn from the existing 5T gearbox design technology and methods. On the basis of its theory, collect its common failure modes, analyze its failure factors, and provide raw materials for design improvement.
2) the structure optimization and strength analysis of the key parts of the improved gearbox.
Combined with the actual situation of loader and engineering machinery manufacturing actual situation, working pump, steering pump, the use and manufacture of transmission pump, according to the working medium pump, steering pump, variable speed pump spline extrusion stress is less than the allowable value; the maximum torque of clutch torque converter stall output contact the stress calculation, other conditions should be lower than this value by three; a bolt connection structure, gear shaft and gear tooth ring direct bolt structure, optimization design of connecting plate connecting structure of direct file, calculate the sufficient strength; through disc spring structure optimization design, calculation and analysis of its life enough calculation; friction torque is transmitted through the second gear, the friction torque shows enough. By contrast, the strength design theory and the improvement of the key technical parameters of life are better than the original ZL50 type gear box planetary Transmission case.
3) the structure of the gearbox is optimized and the strength analysis is carried out.
Through a case of improved gearbox finite element analysis of deformation, displacement response curve of V shaft bearing seat, and the calculation results and the model of displacement distribution is consistent with the actual situation, proved that the gearbox the displacement response model is correct and calculation. The overall structure of the box layout is reasonable, in the area of strict control of casting defects should be changed; the regional distribution of stiffened plate vibration and improve the best on the output flange, which is part of reducing vibration, to maintain the original proposal before the output flange fixed plate layout unchanged, with anti deformation measures, increase the rigid fixation and five axle under the torus constraints consider the degree of difficulty of implementation process in the rear frame of loader, taking into account the cost and improvement in the overall layout, the structure has been established, in order to reduce the five box front output leakage fault, the weak structure improvement It is a more mature direction to distribute and reduce the deformation of the stiffeners, and draw lessons from the characteristics of the sealing structure at home and abroad, adopt the way of "back to back" installation, adopt imported oil seal materials, and adopt reasonable process assembly methods.
4) experimental study of gearbox
According to the improved gearbox test technical index of the test system for gear box no-load power loss, the improved gearbox shifting process, sample working pressure, transmission efficiency, temperature rise characteristics and reliability test, evaluate its performance and reliability, and compared with the original strain ZL50 the box, the suggestion is put forward for optimizing design.
(1) the gearbox's no load power loss is too large and the efficiency is low. The main reason may be the low efficiency of the torque converter, and the low gear machining accuracy in the gearbox. It is suggested that the machining accuracy level of the gear parts should be increased appropriately, so as to improve efficiency and reduce vibration and noise.
(2) the improved overrunning clutch is in good condition in the heavy load test and the carrying cycle reliability test.
(3) the oil leakage in the front output shaft of the gearbox should be strengthened, and the assembly quality control of the oil seal and the seal ring should be strengthened.
(4) the rest of the improved parts have not been abnormally tested by the intensifying test. It is suggested that a small batch assembly should be tried.
Through a broad understanding of domestic and abroad loading machine gearbox manufacturing technology, careful analysis of 5t loader gearbox failure prone mechanism, theoretical calculation and test results, and put forward the implementation of structural optimization of active and effective manufacturing process control. After each index test of the gearbox are better than the original planet ZL50 gearbox, to achieve the desired effect.

【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH243.1

【参考文献】