Power transmission system with helical planetary gears

摘要

A power transmission system comprises planetary gears including: first and second integrated pinion gears made of helical gears of different diameters; a carrier bearing the first and second pinion gears rotatably; a ring gear made of a helical gear meshing with the first pinion gear; and a sun gear made of a helical gear meshing with the second pinion gear. The power is transmitted, by using one of the carrier, the ring gear and the sun gear as a reaction element, between the remaining two elements through the first and second pinion gears. The relation between the angles of torsion of the tooth traces of the first and second pinion gears is so set on the basis of the ratio between the diameters of the two helical gears that the first and second pinion gears may not exert a thrust force upon another member. <IMAGE>