ELECTRIC POWER STEERING DEVICE

PROBLEM TO BE SOLVED: To provide an electric power steering device that transmits rotation of an assist motor to a steering system at a transmission ratio in the same rotational direction or in the reverse rotational direction. SOLUTION: A transmission device 50 is provided with an input shaft 60, to which output of an assist motor 40 is transmitted, an output shaft 70, in which its shaft center line and the input shaft 60 are connected to a rack shaft 27 in parallel, and a roller 81 that partially contacts with both of a spherical recessed part 62, which is provided so as not to allow a shaft center line L2to pass therethrough centering around a shaft center line L1at the flange 61 of the input shaft 60, and an annular recessed part 72, which is annularly provided centering around the shaft center line L2so that a cross-section, having the same shape as that of the spherical recessed part 62 on a plane including the shaft center lines L1, L2, faces the cross-section of the spherical recessed part at the flange 71 of the output shaft 70. A variable speed motor 90 tilts a roller rotary shaft 82 so as to change an angle that a shaft center line L3and the shaft center line L1intersect with each other. COPYRIGHT: (C)2009,JPO&INPIT