Abstract: An oil supply structure for a planetary gear device includes: a planetary gear device including a tubular body that rotates together with a carrier that holds planetary gears, the tubular body including a lubricating oil introduction port formed therein; an annular body that slides against the tubular body, the annular body including a lubricating oil supply passage that communicates with the lubricating oil introduction port; a pair of seal rings attached to the tubular body or the annular body at both sides of the lubricating oil introduction port in an axial direction; bypass passages bypassing the pair of respective seal rings; and a pair of pressure reduction mechanisms disposed between the lubricating oil introduction port and the pair of seal rings or disposed outside the pair of seal rings, the pair of pressure reduction mechanisms each limiting a flow of lubricating oil between the tubular body and the annular body.

Abstract: An oil supply structure for a planetary gear device includes: a planetary gear device including a tubular body that rotates together with a carrier that holds planetary gears. the tubular body including a lubricating oil introduction port formed therein; an annular body that slides against the tubular body, the annular body including a lubricating oil supply passage that communicates with the lubricating oil introduction port; a pair of seal rings attached to the tubular body or the annular body at both sides of the lubricating oil introduction port in an axial direction; bypass passages bypassing the pair of respective seal rings; and a pair of pressure reduction mechanisms disposed between the lubricating oil introduction port and the pair of seal rings or disposed outside the pair of seal rings, the pair of pressure reduction mechanisms each limiting a flow of lubricating oil between the tubular body and the annular body.

Abstract: A planetary gear reduction system has a sun gear, a plurality of planet gears, a ring gear, and a planet carrier. The planet carrier has a first plate supporting one ends of planet shafts supporting the planet gears, a second plate supporting the other ends of the planet shafts, and a cylindrical drum connecting the first and second plates.

Abstract: A planetary reduction gear apparatus has a sun gear having external teeth; planetary gears, each having external teeth and configured to be meshed with the sun gear; planetary shafts, each being a rotation shaft of the planetary gear; a ring gear having internal teeth and configured to be meshed with the planetary gears; and a planetary carrier including an annular base plate and an annular back plate. The planetary carrier supports the planetary shafts between the annular base plate and the annular back plate and determines a relative position between planetary gears. The annular base plate is integrally formed with one end of the planetary shaft to support the one end. The annular back plate supports the other end of the planetary shaft. At least one of the planetary shaft and the planetary carrier has lower stiffness in its part adjacent to the one end of the planetary shaft than stiffness of its part adjacent to the other end thereof.

Abstract: A planetary gear reduction system has a sun gear, a plurality of planet gears, a ring gear, and a planet carrier. The planet carrier has a first plate supporting one ends of planet shafts supporting the planet gears, a second plate supporting the other ends of the planet shafts, and a cylindrical drum connecting the first and second plates.

Abstract: This apparatus includes: a sun gear having external teeth; planetary gears, each having external teeth and configured to be meshed with the sun gear; planetary shafts, each being a rotation shaft of the planetary gear; a ring gear having internal teeth and configured to be meshed with the planetary gears; and a planetary carrier including an annular base plate and an annular back plate. The planetary carrier supports the planetary shafts between the annular base plate and the annular back plate and determines a relative position between planetary gears. The annular base plate is integrally formed with one end of the planetary shaft to support the one end. The annular back plate supports the other end of the planetary shaft. At least one of the planetary shaft and the planetary carrier has lower stiffness in its part adjacent to the one end of the planetary shaft than stiffness of its part adjacent to the other end thereof.