Belt speed reducing apparatus for electric power steering apparatus and electric power steering apparatus

摘要

A belt speed reducing apparatus for an electric power steering apparatus includes a drive pulley having a first helical gear, a driven pulley having a second helical gear and a drive belt having a third helical gear in which a relationship of tan beta<mu is established between a twist angle beta of the respective helical gears and a friction coefficient mu between the first or the second helical gear and the third helical gear. Further, an electric power steering apparatus for adjusting a backlash between gears of a speed reducing apparatus brought in mesh with each other or adjusting a tension of a belt of a speed reducing apparatus.