圆柱齿轮公差与检测

一、齿轮面齿的点失蚀效形式Tooth surface pitting
原因：由于在齿面啮合处脉动循环变接触应力长期作 用下，当应力峰值超过材料的接触疲劳极限，经过一
定应失力效循环形次式数后，先在节线附近的齿廓表面产生细
微的疲劳裂纹。随着裂纹的扩展，将导致小块金属剥 落，产生齿面点蚀。Reason:Because of the long term effect of pulsating cyclic variable contact stress on meshing point of tooth surface.When peak stress exceeds material’s contact fatigue limit, hairlike fatigue cracks will appear on tooth profile surface around nodel line after certain number of times of stress cycle.With the extending of flaws. Scrap metal will peel off to produce tooth surface pitting. 点蚀不良影响：影响轮齿正常啮合，引起冲击和噪声， 造成传动的不平稳。 Harmful effects of pitting:Influencing the normal engagement of gear teeth,causing concussions and noise,creating un-stationary transmission.
Power gear:The speed of revolution is not high and it transmits torque(mining machine and hoisting machinery)
分度齿轮：精确回转（精密机床 仪表中的分度装置）
Dividing gear:Precise rotation(precision machine tool and dividing device in instrumentation)
齿轮传动的类型 Types of gear
drive
传动齿轮：转速较高，功率较大 （汽车 飞机等变速装 置）
Drive gear:Higher rotation rate and power(Speed variators in automobiles and airplanes)
动力齿轮：转速不高，传递扭矩（矿山机械 起重机械）
特点 Traits 1 结构紧凑 Compact structure 2 恒定的传动比 Constant transmission ratio 3 传动效率高 High transmission efficiency 4 可实现平行轴、相交轴和交错轴之间 的传动 It could realize the transmission between parallel axles, intersectant axles and interlaced axles 5 使用寿命长 Long working life 6 维护保养简单 Sample to maintain
The fatigue fracture which is caused by oft-repeated bending stresses and stress concentration.
2.由于突然严重过载或冲击 载荷作用引起的过载折断。
The overload break which is caused by sudden severe overload or impact load.
第7章 圆柱齿轮
公差与配合应用 Chapter 7 Cylindrical gear's
tolerance and fit application
基本要求 Basic requirements
目的：了解圆柱齿轮的公差标准
Aim:To understand tolerance standards of Cylindrical gear
操作技能：评定指标的检验 Manipulative skill:The
test of evaluation index.
作用：传递空间任意两轴（平行、相交、交错）的旋转运动，或将转动转换 为移动。Founction:To transmit the revolving movements of any two axles(parallel,intersectant and interlaced) in space.And to convert turn to shift.
直齿轮：齿宽较小的往往发 生全齿折断,齿宽较大的直齿 轮或斜齿轮则容易发生局部 折断。
Straight gear:The gears with smaller breadth of tooth often emerge whole tooth fracture while the straight gears or helical gears with bigger breadth of tooth are easy to emerge local break.
初步掌握： Grasp preliminarily:
1.应用要求、加工误差
Application requirements and manufacturing error
2.评定指标 Evaluation index 3.图样标注 Labels of pattern 4.齿轮精度设计 Design of gear accuracy
缺点：要求较高的制造和安装精度，加工成本高、不适宜远距离传动。 Disadvantages:It needs higher accuracies of manufacture and installment. Conversion cost is high and it is not suitable for long distance transmission.
齿轮传动机构组成
The form of gear transimission mechanism
齿轮副、轴、轴承、箱 体…pair of gears, axles, bearings and boxes…
Leabharlann Baidu效形式 failure mode
轮齿折断
tooth breakage
1.由于多次重复的弯曲应力 和应力集中造成的疲劳折断；