起重机开式齿轮异响原因分析与预防措施

起重机异常振动和声响是常见的故障,特别是开式齿轮的异响在起重机故障中占有很高的比例。本文通过对多台起重机开式齿轮传动异响的分析及异响故障的排除,找出了在齿轮加工、装配以及起重机设计中应注意的有关问题,旨在为从事起重机装配、调试、维修的技术人员提供一些参考。     

点线啮合齿轮与渐开线齿轮啮合特性对比分析

以点线啮合齿轮副与渐开线齿轮副为研究对象,建立两种啮合齿轮的仿真模型,综合对比分析了点线啮合齿轮与渐开线齿轮在啮合传动误差、齿面载荷分布、齿面滑动速度分布、齿面接触应力分布、齿根弯曲应力分布、啮合接触迹线分析等方面的啮合特性。分析得知,点线啮合齿轮在上述啮合特性方面明显优于渐开线啮合齿轮。研究为全面理解点线啮合齿轮的传动特性提供了理论依据,对其推广应用具有一定参考价值。     

直线共轭内啮合齿轮副啮合特性分析

对直线共轭内啮合齿轮副的啮合特性进行了全面分析，包括共轭齿形的求解、啮合过程分析和重合度计算及齿轮参数对重合度的影响等内容。     

线外啮合齿轮传动啮合刚度计算

对变形和误差引起的线外啮合进行了研究与分析，提出了一种基于线外啮合的齿轮传动刚度计算方法。     

计算直齿轮的啮合效率

直齿轮的总效率通常是根据三种类型的功率损失:齿轮啮合、轴承和间隙或者搅拌阻力。一般计算假设外啮合的齿轮效率是E=0.98,内啮合的齿轮效率是E=0.99。但是基于这样的假设,计算功率损失会导致设计中在计算其它系数时的大错误。齿轮的啮合效率可以从下式计算得到     

定力矩比齿轮传动啮合过程的分析

本文针对从动轮齿形为渐开线的定力矩比齿轮传动，考虑其中心距误差和齿距误差对啮合过程的影响，按进，出啮点所处的位置不同，把啮合过程分为２类４种，推导了每种工作过程的进、出啮角计算公式和具体工作过程的判别准则。     

齿轮齿根及心部硬度不足原因分析及修正措施

1引言齿轮的失效,特别是没有明显征兆的失效,往往会带来巨大的损失,甚至导致严重事故。齿轮箱中的齿轮若由于硬度不足产生过量塑性变形,会造成齿轮啮合不良、卡死或断齿,引起设备故障。     

某柴油发动机启动异响优化分析

市场反馈某柴油发动机在转速750 r/min附近,一档爬坡过程中产生异响,一档带空调起步及二档带空调起步均存在异响,起步后异响消失。经过初步故障诊断,确定为前端轮系的皮带打滑异响,皮带打滑异响与皮带、张紧器有密切的关系。经过对皮带刚度及强度、底胶工艺、张紧器阻尼的进一步分析,确认上述因素为产生皮带打滑异响的根本原因。在采取皮带和张紧器的整改方案后,完成400小时交变试验验证,验证效果良好。     

水泵非传动端轴承损坏原因分析及处理

通过分析VENUS V1-12000.1000C立式水泵运行情况,提出了该泵非传动端轴承损坏的原因和相应的解决方法.     

准双曲面齿轮振动噪声试验与预估分析研究

为研究准双曲面齿轮传动机构的啮合振动、辐射噪声与传动误差的关系,建立三者之间的数据同步检测模型;并利用Y9550型锥齿轮滚动检验机搭建了综合试验平台。通过对一副准双曲面齿轮的振动与噪声信号的采集数据对比,分析振动与噪声的时域特征,并进一步分析振动与噪声谱中的频域相关特性。在Kato公式的基础上引伸出准双曲面齿轮的定量分析式,并借助传动误差的检测结果,对多次采集的数据进行以振动代替噪声的预估计算,试验结果表明:准双曲面齿轮的啮合振动能够较准确地反映出传动噪声的状态,并能够反馈到齿轮设计层面上,从而达到降低齿轮振动与噪声的目的,提高传动系统的稳定性。     

FY卫星系统云图失真问题的一种解决方法

本文针对在保障民航FY静止气象卫星云图接收处理系统运行过程中出现的云图失真故障现象,结合昆明机场卫星接收系统现场安装情况,通过详细分析得出了造成云图失真故障的原因,并给出了故障的解决方法。实践结果表明,本文给出的方法较好地解决了实践工作中出现的投影移位、云层信息大量丢失等云图失真问题。     

康明斯柴油机气缸异常磨损原因分析及对策与检修

分析了重型车柴油机气缸磨损的规律和异常磨损的原因，从实践中总结了减磨措施与对策和诊断检修方法。     

L-55/4.5型空压机油耗量大的原因分析及解决办法

针对L—55／4．5型空压机油耗量大的问题进行原因分析，找出了问题症结所在，对局部结构进行现场改进，控制油耗量在规定范围内。     

Single flank total composite error analysis and noise prediction of gears

The single flank gear error test is known to every gear maker as an all round test of transmission error which implies the smooth running character of gears. A new type of total single flank composite gear error tester has been initiated and produced in China which provides full information about the change-over impact and hence the noise. This article is an in-depth analysis of the total (from tooth tip to root) single flank composite error test and the generation of gear noise. Important conclusions have been made about the ‘favourableness’ of gear geometry and the accuracy on silent transmission.     

齿轮三维建模方法的误差分析

对齿轮的各种建模方法进行了对比分析,提出一种较为精确、可行的建模方法,对各种建模方法的误差及其对齿轮运动精度的影响进行了探索和对比分析,并就如何在虚拟环境中对虚拟的齿轮进行精度检测,提出一种尝试。     

Cavity design method for injection-molded spur gears

Mold cavities of gears should be made larger than the product specification since plastics shrink when changing from a molten to a solid state. For injection molded spur gears, two design methods for the compensation of shrinkage are widely used. One is the module correction method and the other is the pressure angle correction method. Both methods are based on the assumption that shrinkage occurs toward the center of a molded gear. This paper deals with the shrinkage rate and proposes a method of designing gear cavity derived from the measured shrinkage rates which govern the outside diameter, the tooth depth and the tooth thickness of a molded gear. The proposed method imposes no restriction on the shrinkage direction and provides a cavity with all of the fundamental gear design parameters.     

Durability improvement method for plastic spur gears

An experimental investigation of power-transmission plastic spur gears was performed by inspecting both the characteristics of wear and durability, and a durability improvement method is proposed that either drills an internal hole or inserts a steel-pin in the internal hole of the gear tooth, and this proposed method was verified. In the case of acetal gears, the amount of wear was observed to increase with the development of plastic deformation, and an increase in tooth stiffness occurred due to the brittle material property of acetal. On the other hand, in the case of nylon gears, the proposed method was shown to reduce the tooth temperature compared to the original gear, thus reducing the amount of wear and prolonging service life. Hence, the proposed method was proven to be practically applicable to plastic gears made from soft polymers that show visco-elastic properties such as nylon.