圈上泽支大峰 Acme thread-Load Raising For other threads(not square thread),the normal force acts at an angle. Angle increases frictional force by wedging action of the threads. Can be accounted for by dividing angle frictional terms by cosa 圆上泽夫道大峰 Effect of Thread Angle ▣Raise Load: T= +dm seca 2 nd-flseca ▣Lower Load: 2a= Thread T= Fd nfd seca-l angle 2 πdnm+flseca 2424  For other threads( not square thread), the normal force acts at an angle.  Angle increases frictional force by wedging action of the threads.  Can be accounted for by dividing frictional terms by cosα α Acme thread——Load Raising  Raise Load:  Lower Load:                sec sec 2 d fl Fd l fd T m m m               sec sec 2 d fl Fd fd l T m m m － α Effect of Thread Angle