Positive SSL
1 有一四線螺紋,其螺距為2mm,設導程角(lead angle)為α,已知tanα=1/3π,則節圓直徑為多少mm?
A 8
B 12
C 16
D 24
tanθ=L/πd = 4P/πd = 8/πd = 1/3π => d =24