Oscillating internally meshing planetary gear reducer

Abstract

To provide an oscillating internally meshing planetary gear reducer capable of realizing a low cost and a high speed reduction ratio, the oscillating internally meshing type planetary gear reducer is constituted so as to include: an input shaft provided with an input gear which is circumscribed and meshed with a pinion provided on a motor; an input shaft gear formed on the input shaft; a plurality of eccentric body shafts each provided with an eccentric body for oscillating an oscillating external gear; an eccentric body shaft gear which is formed on each eccentric body shaft; and a distributing gear which is meshed with the input shaft gear and the eccentric body shaft gear.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side cross sectional view of a geared motor according to one of embodiments of the present invention.

FIG. 2 is a cross sectional view taken along line II-II indicated by an arrow in FIG. 1.

FIG. 3 is a side cross sectional view of a geared motor according to another one of embodiments of the present invention.

FIG. 4 is a cross sectional view taken along line IV-IV indicated by an arrow in FIG. 3.

FIG. 5 is a side cross sectional view of a geared motor according to the other one of embodiments of the present invention.

FIG. 6 is a side cross sectional view of a conventional geared motor 1.

FIG. 7 is a side cross sectional view of a conventional geared motor 2.

FIG. 8 is a side cross sectional view of a conventional geared motor 2′.

Claims

1. An oscillating internally meshing planetary gear reducer for reducing a speed of an input power via an oscillating external gear, comprising: an input gear which is circumscribed and meshed with a pinion rotating at the same speed as that of an output shaft of an external power source;an input shaft provided with the input gear to receive driving force from the pinion;an input shaft gear mounted on the input shaft;a plurality of eccentric body shafts each provided with an eccentric body for oscillating the oscillating external gear;an eccentric body shaft gear which is mounted on at least one of the eccentric body shafts to make the eccentric body shaft receive the power; anda distributing gear which meshes with the input shaft gear and the eccentric body shaft gear to distribute and transmit rotation of the input shaft gear to the plurality of eccentric body shaft gears.

2. The oscillating internally meshing planetary gear reducer according to claim 1, wherein the input shaft is arranged inside a pitch circle of the oscillating external gear so as to pass through the oscillating external gear.

3. The oscillating internally meshing planetary gear reducer according to claim 1, wherein the input gear has a diameter larger than that of the pinion and the eccentric body shaft gear has a diameter larger than that of the input shaft gear.

4. The oscillating internally meshing planetary gear reducer according to claim 1, wherein the pinion is arranged inside a pitch circle of an internal gear with which the oscillating external gear meshes.

5. The oscillating internally meshing planetary gear reducer according to claim 1, wherein the distributing gear is not directly supported by a bearing, and a position of the distributing gear in a radius direction is regulated by meshing of the input shaft gear and the eccentric body shaft gear.

6. The oscillating internally meshing planetary gear reducer according to claim 1, wherein the input shaft gear, the eccentric body shaft gear and the distributing gear are arranged on an identical plane.

7. The oscillating internally meshing planetary gear reducer according to claim 1, further comprising: a through member which passes through the distributing gear in an axial direction; andone bearing for supporting the distributing gear rotatably in relation to the through member.

8. The oscillating internally meshing planetary gear reducer according to claim 7, wherein the input shaft gear, the eccentric body shaft gear, the distributing gear and the bearing are arranged on an identical plane.

9. The oscillating internally meshing planetary gear reducer according to claim 7, wherein the through member is a hollow cylinder.

10. The oscillating internally meshing planetary gear reducer according to claim 7, wherein the bearing has a plurality of rollers, and an outer circumferential surface of the through member and an inner circumferential surface of the distributing gear serve as a rolling surface for the rollers.

11. The oscillating internally meshing planetary gear reducer according to claim 1, wherein a plurality of oscillating external gears are stacked on each other in an axial direction, andthe distributing gear is arranged between the oscillating external gears so that a position thereof in an axial direction is regulated.

12. The oscillating internally meshing planetary gear reducer according to claim 1, wherein the distributing gear is arranged between the oscillating external gear and a carrier body for taking out a rotation component of the oscillating external gear so that a position thereof in an axial direction is regulated.