Schaeffler North America

Safety and mechatronics

Overrunning alternator pulley

The purpose of the overrunning alternator pulley is to decouple the generator from the rotational irregularities in the crankshaft of an internal-combustion engine, since the generator has the largest mass moment of inertia in the accessory drive. To drive the generator in this way, only the accelerating sections of the crankshaft's rotational irregularities are used.

Special features:

  • Reduced forces in the belt drive
  • Reduced tensioner travel
  • Increased belt service life
  • Improved noise behavior in the belt drive
  • Increased generator speed in the idle speed area
  • Reduced belt slip and noise from the generator drive wheel during gear changes