上海交通大学：《Design and manufacturing（ME371、ME337）》课程教学资源（讲义）Lecture 13 Bearings

图 上酒短大峰 色h人A口 LECTURE 15 ME371/ME337 DESIGN AND MANUFACTURING Bearings Covered in Cha11 Mechanical Engineering Design SHAN 国上清通大学 Lectures Power/Energy Conversion (Electrical Motors) Power/Energy Transmission (Gears,Cam,Linkage Belt Drives, Power Screws) Joints Transmission (Fasteners, Support Connectors) (Bearings) Structural Support (Frames) Tools Statics,Dynamics, Stress Analysis,etc. 1

1 Bearings LECTURE 15 ME371/ME337 DESIGN AND MANUFACTURING Covered in Cha11 Mechanical Engineering Design Lectures Power/Energy Conversion (Electrical Motors) Transmission Support (Bearings) Joints (Fasteners, Connectors) Structural Support (Frames) Tools Statics, Dynamics, Stress Analysis, etc. Power/Energy Transmission (Gears, Cam, Linkage, Belt Drives, Power Screws)

上酒短大峰 Outline ▣Introduction ▣Rolling bearing Types ▣Bearing Life ▣Bearing Design 国 上酒文通大学 Why Bearings Bearing is defined by Webster's to be"a support or supporting part'” In machine design,a bearing is a component that allows for relative motion between two bodies ▣Bearings are for:: reduce friction >carry load >guide of moving parts Rotary Encoder ☒I AC Brushless Motor Flexible Coupling Rearing Housing Ballscrew Ballnut Support Bearings 2

2  Introduction  Rolling bearing Types  Bearing Life  Bearing Design Outline Why Bearings  Bearing is defined by Webster’s to be “a support or supporting part”  In machine design, a bearing is a component that allows for relative motion between two bodies  Bearings are for:  reduce friction  carry load  guide of moving parts

图 上海久通大学 Bearings Applications Bearing Bearing 图 上泽充道大学 Principles of Operation 口Rolling Friction(Rolling Contact Bearing滚动轴承) Roller/ball (滚子球) Outer Ring(外圆) Lubrication (润滑剂) ~Inner Ring(内圜) 3

3 Bearings Applications Bearing Bearing Principles of Operation  Rolling Friction (Rolling Contact Bearing 滚动轴承) Roller/ball （滚子/球） Lubrication （润滑剂） Outer Ring（外圈） Inner Ring（内圈）

公 上海久通大学 Principles of Operation 口Sliding Friction(Sleeve Bearing滑动轴承) Hydrodynamic lift is Sleeve(轴承座) generated by fluid being dragged into gap by viscous shear Lubrication Circumferential pressure profile Bushing(轴瓦) 圈上充通大学 History 4

4 Principles of Operation  Sliding Friction (Sleeve Bearing 滑动轴承) Sleeve（轴承座） Lubrication Circumferential pressure profile Hydrodynamic lift is generated by fluid being dragged into gap by viscous shear Bushing（轴瓦） History

图 上海久通大学 Development of the Bearing 3500B.C. 1794A.D. 1869 700B.C 40A.D. CARB 1995 图上涤夫廷大学 Outline ▣Introduction 口Rolling Bearing Types ▣Bearing Life ▣Bearing Design 5

5 Development of the Bearing 700 B.C. 3500 B.C. 40 A.D. 1794 A.D. 1869 1995  Introduction  Rolling Bearing Types  Bearing Life  Bearing Design Outline

图 上海通大学 Types of Loads 口 Radial loads(径向载荷：act toward the center of the bearing along a radius,created by spur gears(直齿轮)，V-belt drives, and chain drives. ▣ Thrust loads(轴向载荷)：act parallel to the axis of the shaft. The axial components of the forces on helical gears(斜齿轮 ),bevel gears(圆锥齿轮)，or supporting shafts with vertical axes. ▣Misalignment(轴线偏斜)：refers to the angular deviation of the axis of the shaft at the bearing from the true axis of the bearing itself. 图 上泽充道大学 Types of Antifriction Bearings 口 Ball Bearings Width→ Corner radius Outer ring 外圆 Shoulders Inner 内 Corner radius 罢 農 Inner ring ball race 染 Separator 保持架 (retainer) 端面 -Outer ring 外圈 Face ball race 6

6  Radial loads(径向载荷): act toward the center of the bearing along a radius, created by spur gears(直齿轮), V-belt drives, and chain drives.  Thrust loads(轴向载荷): act parallel to the axis of the shaft. The axial components of the forces on helical gears(斜齿轮 ), bevel gears(圆锥齿轮) , or supporting shafts with vertical axes.  Misalignment(轴线偏斜): refers to the angular deviation of the axis of the shaft at the bearing from the true axis of the bearing itself. Types of Loads R A Types of Antifriction Bearings  Ball Bearings外径 内径 端面 外圈 滚道 内圈 滚道 保持架 内圈 外圈

图 上海文通大学 Bearings Components Seal Rolling elements Inner ring Outer ring Cage Seal 图上涤夫廷大学 Types of Antifriction Bearings Bearing width Tapered Roller Bearings Cun back face radius r Cup back face Cup front face ▣Components: 保特架Cae -Cone back face rib >Cone =Inner ring C Cone back face >Cup -Cone length 8- =Outer ring >Tapered rollers >Cage Space retainer Cone front- face radius Cone front face- Cone Standout F 7

7 Bearings Components Seal Rolling elements Inner ring Outer ring Cage Seal Types of Antifriction Bearings  Tapered Roller Bearings 保持架  Components: Cone = Inner ring Cup = Outer ring Tapered rollers Cage =Space retainer

图 上海文通大学 Types of Antifriction Bearings 圆上泽支大学 Rolling Elements Ball Spherical Asymmetrical Cylindrical Taper Needle 8

8 Types of Antifriction Bearings Rolling Elements Cylindrical Needle Taper Ball Spherical Asymmetrical

图 上海通大学 Types of Roller Bearings A)Cylindrical(圆柱滚子) B)Spherical(球面滚子) C)Tapered Roller,Thrust (推力圆锥滚子) D)Needle(滚针) E)Tapered Roller (h) (圆锥滚子) F)Steep-angle Tapered Roller(大锥角圆锥滚子) (f) 国上清通大学 Types of Ball Bearings ( id) Filling notch Shielded Sealed 深沟球 有装球缺口 Λ角接触 带防尘盖 带密封圈 Ig 1 } External Double row Self-aligning Thrust Self-aligning thrust 带球面外衬圈 双列球 双列自动调心 单向推力 单向推力带 球面座圈 9

9 Types of Roller Bearings A) Cylindrical（圆柱滚子） B) Spherical（球面滚子） C) Tapered Roller, Thrust （推力圆锥滚子） D) Needle（滚针） E) Tapered Roller (圆锥滚子) F) Steep-angle Tapered Roller（大锥角圆锥滚子） Types of Ball Bearings 深沟球 有装球缺口 角接触 带防尘盖 带密封圈 带球面外衬圈 双列球 双列自动调心 单向推力 单向推力带 球面座圈

图 上海久通大学 Concept of Contact Angle n A (a) (b) (c) 国 上酒充通大学 Types of Ball Bearings 口Single Row Deep Groove BB(单列深沟球轴承) >Spherical balls roll in deep groove in both races >Space maintained by separators(retainers/cages) >Ball radius smaller than groove radius >Mostly take radial loads,some thrust load(轴向载荷) >Theoretical point contact(actually a small circular area),so high local contact stress >Some permissible misalignment 深沟球轴承 10

10 Concept of Contact Angle Types of Ball Bearings  Single Row Deep Groove BB（单列深沟球轴承）  Spherical balls roll in deep groove in both races  Space maintained by separators (retainers/cages)  Ball radius smaller than groove radius  Mostly take radial loads, some thrust load(轴向载荷)  Theoretical point contact (actually a small circular area), so high local contact stress  Some permissible misalignment