ABSTRACT
Two pair reducer is developed very quickly in recent year due to its features such as its simple and compact structure,high driving ratio,large loading capacity and high driving efficiency. But some problems,including great noises,high temperature and the early-worm of bearings oceurring under the condition of high-sheep operation,heavy loading and high transmission ratio,influenced seriously its popularization progerss and are urgent to be solved.
Based on the study of driving principle of current two pair reducer,this dissertation suggested a two-stage coaxial double-ring reducer in the purpose of solving the high vibration and noise problems of two pair reducer under the condition of high-speed and heavy-load operation,Which consists of one-stage cylindrical gearing and one-stage dual-ring gearing.Bases on the analysis of the transmission theory,kinematics,dynamics of the suggested reducer,the anthor designed and manufactured a prototype of the suggested reducer,made some relevant researches and got a satisfying result.The major research works in the paper are listed as follows:
Provided a new-structured two pair reducer two-stage coaxial dual-ring gear reducer,set up its three-dimension model and assembled the model in the virtual condition,analyzed the structure and forces bearing situation of the new reducer 。
Caculated the contact stress of the inner meshing of the dual-ring reducer by means of finite elements method, and learned the maximum stress value and the actual pairs of contact teeth,which became a reliable source for selecting geometry parameter of reducer.
Caculated the inner excitation of gear resulting from varying stiffness and error of gear, analyzed the response of the system by means of vibration superprosition method based on coupling system mode,and predicted the dynamic response of the dual-ring reducer under dynamic inner excitation,and made a broad study of the dynamic characteristics of the reducer.
Designed and manufactured a prototype and tested pacrtieally its effieieney and the dynamic characteristies on gearing system dynamic experiment desk. The test result indicated that the two-stage coaxial double-ring reducer reached an efficiency of 90% and is improved on the vibration.
Key Word: Reducer ,Dynamic Characteristics ,Finite Element
目 录
摘 要: i
ABSTRACT ii
目 录 1
绪 论 4
1.1课题来源及研究的意义 4
1.2两级减速器目前的现状 4
1.3齿轮传动系统动力学国内外研究现状 5
第二章 传动系统运动分析计算 6
2.1工作机转速和所需功率计算 6
2.1.1工作机(卷筒)转速计算 6
2.1.2工作机所需功率的计算 6
2.2电动机的选择 6
2.2.1电动机类型和结构类型的选择 6
2.2.2电机容量的选择 6
2.2.3电动机转速的确定 7
2.2.4计算传动装置的运动和动力参数 8
2.2.5计算各轴输入功率 8
2.2.6计算各轴输入转矩 9
第三章 传动零件的设计计算 9
3.1直齿圆锥齿轮 9
3.2齿轮各项参数确定 10
3.2.1齿数 10
3.2.2模数 11
3.2.3大端分度圆直径 11
3.2.4节锥顶距 11
3.2.5节圆锥角 11
3.2.6大端齿顶圆直径 11
3.2.7齿宽b 12
3.2.8齿宽中点分度圆上的名义切向力的计算 12
3.2.9接触强度计算的有效齿宽的计算 12
3.2.10接触强度计算的齿向载荷分布因数的计算 13
3.2.11接触强度计算的锥齿轮因数的确定 13
3.2.12材料弹性模量系数的确定 13
3.2.13动载因数的确定 13
3.2.14齿间载荷分配因数的确定 13
3.2.15接触强度计算的寿命因数的确定 14
3.2.16齿面工作硬化因数的确定 14
3.2.17尺寸因数的确定 14
3.3直齿圆锥齿轮轮齿弯曲强度校核 15
3.3.1弯曲强度安全因数的确定 17
3.3.2齿轮尺寸 17
3.3.3斜齿圆柱轮 17
3.3.4齿轮 17
第四章 初步确定齿轮的主要参数 18
4.1按接触强度估算齿轮中心距 18
4.2按齿根弯曲强度估算齿轮模数 18
4.3初定齿轮几何参数 19
4.4计算圆周速度,选择齿轮精度等级 20
4.5校核齿面接触疲劳强度 20
4.5.1材料弹性模量系数的确定 21
4.5.2重合度因数的确定 21
4.5.3螺旋角因数的确定 21
4.5.4计算齿面接触应力 21
4.5.5确定式中各参数: 22
4.5.6润滑因数的确定 22
4.5.7齿面工作硬化因数的确定 22
4.5.8尺寸因数的确定 22
4.5.9接触强度安全因数 23
第五章 校核齿根弯曲疲劳强度 23
5.1计算齿根弯曲应力 23
5.1.1确定式中各参数: 23
5.1.2综合齿形系数 23
5.1.3重合度因数 24
5.1.4螺旋角因数 24
5.1.5计算弯曲应力: 24
5.1.6计算弯曲强度安全因数 24
5.1.7齿轮尺寸 26
第六章 传动轴承和传动轴的设计 26
6.1计算输出轴上的功率、转速和转矩 26
6.2计算作用在齿轮上的力 26
6.3初步确定轴的最小直径 27
第七章 轴的结构设计 27
7.1拟定轴上零件的装配方案 27
7.2初步选择滚动轴承 28
7.2.1确定安装齿轮处轴段的直径 28
7.3确定齿轮右边轴环的直径和长度 28
7.4确定轴上零件的周向固定 29
7.5确定轴上圆角和倒角尺寸 29
7.6选择轴的材料 29
7.7计算轴上载荷 29
7.7.1水平面内 30
7.7.2垂直面内 30
7.7.3总弯矩和转矩 30
7.7.4按弯扭合成应力校核轴的强度 31
7.8滚动轴承寿命计算 32
7.9计算轴向载荷 33
7.9.1计算当量动载荷, 33
7.9.2验算轴承额定寿命 33
第八章 总结 34
参考文献 34
致谢 35