DIN 3975-1:2025-12

This document specifies definitions and parameters for cylindrical worm gear pairs with flank forms A, C, I, K, and N. These definitions and parameters apply to wheel sets, worms, worm wheels, tooth thickness dimensions, and backlash. DIN 3975-2 applies to deviations. The standard differs from DIN 3975-1:2017-09 as follows: a) subclauses 3.1 through 3.4 have been supplemented; b) equation (49) has been corrected; c) caption for Figure 10 has been corrected; d) the variable scaling of the form factor q has been added in Figure 14; e) Figures 29 and 31 have been corrected; f) the standard has been editorially revised. This document has been prepared by Working Committee NA 060-34-14 AA "Schneckenverzahnungen (SpA ISO/TC 60/SC 1/WG 7)" ("Worm gears") of Section "Antriebstechnik" ("Gear") at DIN Standards Committee Mechanical Engineering (NAM). Representatives of manufacturers and users of worm gears as well as representatives from universities participated in its preparation.