Belt tightener having a spur gear

Abstract

A belt tensioner for a seatbelt system comprising a spur gearing (18). The spur gearing (18) comprises at least one motor gearwheel (24) and at least a first stepped wheel (26) and a second stepped wheel (28). The motor gearwheel (24) forms a first gear stage (34) with the first stepped wheel (26), and the first stepped wheel (26) forms a second gear stage (36) with the second stepped wheel (28). The motor gearwheel (24) and each of the stepped wheels (24, 26) include helical teeth, and the helix angle of the helical teeth of the second gear stage (36) is determined depending on the helix angle of the first gear stage (34). The overlap ratio of at least one helical toothing is not integer.

Dependencies are inferred from the claim text.