Increased Tooth Bending Strength and Pitting Load Capacity of Fine Module Gears

Miniaturization is one of the major trends for future drivetrain design. Hence more and more small motors and gearboxes are available at the market. Also components like gears becoming smaller. Modules of 1 mm and less are not unusual. But the common calculation methods according to ISO 6336 and DIN 3990 are mainly verified for gears with module 3 mm — 10 mm. These investigations showed a decreasing load-carrying capacity for tooth bending strength and pitting resistance with increasing gear size. But for gears with module less than 5 mm, a size effect is not thus far considered in the calculation methods.