Patent ID: 9169910
Filing Date: 2015-10-27
Classification: F16H,Y10T

Abstract:
1. A gear device for reducing speed of an inputted driving rotation to be outputted, comprising: an eccentric cam rotatably formed and including a support portion with an axis center arranged eccentrically relative to a rotational axis center of the eccentric cam; an internally toothed gear provided at a position to be coaxial to the rotational axis center of the eccentric cam; an externally toothed gear supported by the support portion and engaged with the internally toothed gear, the externally toothed gear-including smaller number of teeth than the internally toothed gear; an output portion integral with the externally toothed gear, the output portion rotating coaxially with the externally toothed gear; and a bearing portion supporting the output portion in a state where an axis line of the output portion and the externally toothed gear slants relative to the rotational axis center of the eccentric cam in a manner crossing the rotational axis center of the eccentric cam; wherein each of the internally toothed gear and the externally toothed gear includes a bevel gear portion which is formed by forming gear teeth on a circular cone whose apex overlaps with an intersection point of the axis line and the rotational axis center, each of the internally toothed gear and the externally toothed gear includes a spur gear portion arranged coaxially with the bevel gear portion, and the spur gear portions of the internally toothed gear and the externally toothed gear are engaged with each other, the bearing portion includes an insertion hole which is arranged coaxially with the eccentric cam and the internally toothed gear and to which the output portion is inserted to be positioned; and the bearing portion supports the output portion in a state where an outer circumference of the output portion slidably contacts an inner circumference of the insertion hole, and the output portion is formed with a slidably contacting convex surface which curves in a spherical shape on an outer circumference thereof; and the insertion hole is formed with a slidably contacting concave surface which curves in a spherical shape corresponding to the slidably contacting surface on an inner circumference thereof.