Bendix drive

Bendix drive
Patent Drawing (colored):
  • 1: electric motor
  • 5: rotatable screw shaft
  • 6: pinion
  • 8: coiled spring
  • 13: flywheel

A Bendix drive is a type of engagement mechanism used in starter motors of internal combustion engines. The device allows the pinion gear of the starter motor to engage or disengage the ring gear (which is attached to the flywheel or flexplate of the engine) automatically when the starter is powered or when the engine fires, respectively. It is named after its inventor, Vincent Hugo Bendix.