图上涤支大峰 OUTLINE Power Screw Introduction ©Basic Terminology ©Torque Loading ©Other issues 圆上海文大学 Basic Terminology 口Pitch,p(螺距) Maje dimteder >Distance between adjacent thread forms 一Pitch dumeter measured parallel to the thread axis. Mior diameler ▣Major Diameter,d(大径) >Largest diameter of a screw thread. ▣Minor Diameter,.d,(小径) >Smallest diameter of a screw thread 口Pitch Diameter,d,(中径) >The effective diameter of the screw Sometimes called the mean diameter,dm 88 OUTLINE Power Screw Introduction Basic Terminology Torque Loading Other issues Basic Terminology  Pitch, p（螺距）  Distance between adjacent thread forms measured parallel to the thread axis.  Major Diameter, d（大径）  Largest diameter of a screw thread.  Minor Diameter, dr （小径）  Smallest diameter of a screw thread  Pitch Diameter, dp（中径）  The effective diameter of the screw  Sometimes called the mean diameter, dm