ECCENTRIC OSCILLATION GEAR DEVICE AND METHOD FOR PRODUCING ECCENTRIC OSCILLATION GEAR DEVICE

摘要

Disclosed is an eccentric oscillation gear device which rotates a second counterpart member with respect to a first counterpart member at a rotational speed obtained by reducing an input rotational speed at a predetermined rotational speed ratio. The eccentric oscillation gear device is provided with an external cylinder which is connected to the first counterpart member and which has an inner surface provided with a plurality of internal teeth; a crank shaft which has an eccentric portion and which rotates about an axis of the crank shaft within the external cylinder by a rotative force being input to the crank shaft; an externally toothed gear which is attached to the eccentric portion and which oscillates and rotates in association with an eccentric rotation of the eccentric portion while meshing with the internal teeth; a carrier which is connected to the second counterpart member and fitted in the external cylinder and which rotates about an axis of the external cylinder with respect to the external cylinder by receiving a rotative force of the externally toothed gear; and a carrier bearing which supports the carrier within the external cylinder with respect to the external cylinder so that the carrier is rotatable about the axis of the external cylinder. The carrier bearing has an inner ring portion which is fitted onto the carrier and which is rotatable about the axis of the external cylinder integrally with the carrier, an outer ring portion which is fitted in the external cylinder and which is rotatable about the axis of the external cylinder integrally with the external cylinder, and a roll member which is rotatably disposed between the inner ring portion and the outer ring portion. A gap in which the roll member is movable in a radial direction of the external cylinder is formed between the inner ring portion and the outer ring portion.