Patent ID: 8657578

Claim:
A gear box for a wind turbine generator which comprises a main shaft coupled to a rotor head with blades and configured to rotate with the rotor head, the gear box comprising: a casing; a carrier having a plurality of planet pins and rotating with the main shaft of the wind turbine generator; planet roller bearings installed to the planet pins of the carrier, respectively, each of the bearings including rollers provided between an inner race and an outer race; a plurality of planet gears supported rotatably to the planet pins via the planet bearings, respectively; a ring gear provided in the casing and having an inner tooth meshed with the planet gears; a sun gear surrounded by the planet gears and meshed with the planet gears; and an oil bath provided in a lower part of the casing and configured to reserve lubrication oil inside, wherein the carrier comprises an outer cylinder part provided on both ends of the planet pins in an axial direction of the planet pin and surrounding the outer circumference of the both ends of the planet pins so as to hold the planet pins, and wherein the outer cylinder part of the carrier includes an inclined surface facing the planet bearing, the inclined surface inclining outward from the planet bearing in a radius direction of the planet pin, wherein the outer race has end faces in the axial direction, the end faces of the outer race including a first end face that is the nearest to the outer cylinder part, wherein the inner race has end faces in the axial direction, the end faces of the inner race including a second end face that is the nearest to the outer cylinder part, and wherein at least a part of the inclined surface is located between the first end face of the outer race and the second end face of the inner race as seen in the axial direction.