SPEED REDUCTION GEAR OF ELECTRIC POWER STEERING DEVICE

摘要

An electric power steering device having a speed reduction gear using a toothed belt and capable of preventing the speed reduction gear from being locked and steering frombeing disabled even if the toothed belt is broken. A clearance ” between the inner surface (21x) of the second housing (21b) of the speed reduction gear (40) and the rear surface (29a) of the toothed belt (29) applied to a toothed pulley (27) is formed larger than the tooth depth (H) of the toothed belt (29) (” > II). Thus, even if the toothed belt (29) is broken, the toothed belt (29) is not caught between the inner surface (21x) of the second housing (21b) and the outer peripheral surface (27a) of the second toothed pulley (27), and the toothed pulley (29) is not locked.