Patent ID: 7600602

Claim:
A motor-driven power steering apparatus in which a rotating torque of an electric motor is transmitted to a steering shaft by a drive gear provided in an output shaft of said electric motor and a driven gear provided in said steering shaft, and a speed reduction ratio is equal to or more than 3, wherein said steering shaft and the output shaft of said electric motor are arranged in almost parallel, a center distance between both the shafts is equal to or more than 35 mm and equal to or less than 90 mm, and wherein said drive gear has at least 6 and no more than 15 teeth, a module of said drive gear is at least 0.8 and no more than 1.5, a tooth depth of said drive gear is equal to or less than 2.4 times of the module, a pressure angle of said drive gear is at least 14.5 degrees and no more than 30 degrees, and a torsion angle of said drive gear is at least 0 degrees and no more than 40 degrees.