Budynas-Nisbett Shigleys I Design of Mechanical 14.Spur and Helical Gears T©The McGraw-Hil m Mechanical Engineering Elements Companies,2008 Design,Eighth Edition 4 Spur and Helical Gears Chapter Outline 14-1 The Lewis Bending Equation 714 14-2 Surface Durability 723 14-3 AGMA Stress Equations 725 14-4 AGMA Strength Equations 727 14-5 Geometry Factors I and J(Z and Y1 731 14-6 The Elastic Coefficient Cp (Z 736 14-7 Dynamic Factor K,736 14-8 Overload Factor K。738 14-9 Surface Condition Factor Cr (Zel 738 14-10 Size Factor K 739 14-11 Load-Distribution Factor Km(KH 739 14-12 Hardness-Ratio Factor CH 741 14-13 Stress Cycle Life Factors YN and ZN 742 14-14 Reliability Factor Ke(Y 743 14-15 Temperature Factor KT (Ya 744 14-16 Rim-Thickness Factor K8 744 14-17 Safety Factors Se and SH 745 14-18 Analysis 745 14-19 Design of a Gear Mesh 755 713Budynas−Nisbett: Shigley’s Mechanical Engineering Design, Eighth Edition III. Design of Mechanical Elements 14. Spur and Helical Gears © The McGraw−Hill 711 Companies, 2008 Spur and Helical Gears Chapter Outline 14–1 The Lewis Bending Equation 714 14–2 Surface Durability 723 14–3 AGMA Stress Equations 725 14–4 AGMA Strength Equations 727 14–5 Geometry Factors I and J (ZI and YJ) 731 14–6 The Elastic Coefficient Cp (ZE) 736 14–7 Dynamic Factor Kv 736 14–8 Overload Factor Ko 738 14–9 Surface Condition Factor Cf (ZR) 738 14–10 Size Factor Ks 739 14–11 Load-Distribution Factor Km (KH) 739 14–12 Hardness-Ratio Factor CH 741 14–13 Stress Cycle Life Factors YN and ZN 742 14–14 Reliability Factor KR (YZ) 743 14–15 Temperature Factor KT (Yθ) 744 14–16 Rim-Thickness Factor KB 744 14–17 Safety Factors SF and SH 745 14–18 Analysis 745 14–19 Design of a Gear Mesh 755 14 713