US Patent 11300007 Planetary gearbox having compliant journal bearings

A planetary gear train for an aircraft engine, has: a sun gear; planet gear assemblies having main gears meshed with the sun gear, fore lateral gears and aft lateral gears disposed on opposite sides of the main gears and rotating therewith; journal bearings rotatably supporting the planet gear assemblies for rotation about rotation axes, gaps defined between the journal bearings and the planetary gear assemblies; a planet carrier supporting the journal bearings; a fore ring gear meshed with the fore lateral gears; an aft ring gear meshed with the aft lateral gears; and a lubrication system extending within the planet carrier and hydraulically connected to the gaps between the journal bearings and the planet gear assemblies.