Patent attributes
The present invention relates to a power transmission device of an electric power steering apparatus. The power transmission device includes: a driving shaft of a motor having an accommodation part formed at a rotation center thereof; a coupling member inserted into the accommodation part and having an axial through-hole formed therethrough; and a gear shaft including a coupling part formed on one side thereof to be coupled to the axial through-hole, and a gear part formed on the other side thereof. According to the present invention as described above, in a power transmission device of an electric power steering apparatus, it is possible to reduce rattle noise generated as backlash increases due to wearing-out of a gear or generated due to impact transmitted from a road surface through a vehicle wheel and a steering shaft while improving a driver's steering feeling by reducing a locking feeling and a rotational resistance between a driving shaft of a motor and a gear shaft.