Planetary reduction gear device

Patent metadata

Field	Value
Publication number	US-10215259-B2
Application number	US-201715424090-A
Country	US
Kind code	B2
Filing date	Feb 3, 2017
Priority date	Feb 8, 2016
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

A planetary reduction gear device has first and second planetary gears meshed with a sun gear and an internal at different locations in a direction of an axis line; and a carrier assembly for supporting the first and second planetary gears. The carrier assembly has a first planetary carrier for supporting the first planetary gears and a second planetary carrier for supporting the second planetary gears. The first and second planetary carriers are fixed coaxially with each other in the direction of the axis line so as to rotate integrally. A planetary reduction gear device having a large torque capacity can be obtained.

First claim

What is claimed is:

1. A planetary reduction gear device comprising:
a sun gear;
an internal gear;
at least first and second planetary gears meshed with the sun gear and the internal gear at different locations in a direction of an axis line; and
a carrier assembly for supportinq the first and second planetary gears, wherein
the carrier assembly has a first planetary carrier for supportinq the first planetary gear and a second planetary carrier for supporting the second planetary gear; and
the first and second planetary carriers are fixed coaxially with each other in the direction of the axis line so as to rotate integrally, wherein
a plurality of the first planetary gears and a plurality of the second planetary gears are provided;
the first planetary gears are arranged at prescribed angular intervals in a circumferential direction on a first location in the direction of the axis line between the sun gear and the internal gear;
the second planetary gears are arranged at prescribed angular intervals in a circumferential direction on a second location in the direction of the axis line between the sun gear and the internal gear, the second location being different from the first location in the direction of the axis line;
the first planetary carrier supports a plurality of first planetary shafts on both sides of the first planetary gears, the first planetary shafts supporting the first planetary gears in a rotatable state; and
the second planetary carrier supports a plurality of second planetary shafts on both sides of the second planetary gears, the second planetary shafts supporting the second planetary gears in a rotatable state.

2. The planetary reduction gear device according to claim 1 , wherein
the first planetary carrier has a first shaft support plate and a second shaft support plate located on both sides of the first planetary gears in the direction of the axis line, and the first planetary shafts are bridged between the first and second shaft support plates; and
the second planetary carrier has a third shaft support plate and a fourth shaft support plate located on both sides of the second planetary gears in the direction of the axis line, and the second planetary shafts are bridged between the third and fourth shaft support plates.

3. The planetary reduction gear device according to claim 2 , wherein
the second and third shaft support plates located between the first and second planetary gears are connected with each other.

4. The planetary reduction gear device according to claim 2 , wherein
a single common shaft support plate is arranged in place of the second and third shaft support plates.

5. The planetary reduction gear device according to claim 4 , further comprising:
a front-stage planetary reduction part having a front-stage internal gear, a front-stage planetary carrier, a front-stage planetary gear supported in a rotatable manner by the front-stage planetary carrier, and a front-stage sun gear, wherein
the front-stage planetary carrier is fixed in a coaxial manner to the sun gear.

6. The planetary reduction gear device according to claim 5 , further comprising:
an annular device case, wherein
the internal gear is formed on one side of a circular inner peripheral surface in the direction of the axis line of the device case, and the front-stage internal gear is formed on the other side of the circular inner peripheral surface in the direction of the axis line.

7. The planetary reduction gear device according to claim 2 , wherein
the number of the first planetary gears is the same as the number of the second planetary gears; and
the first and second planetary gears are arranged at same angular positions in the circumferential direction.

Assignees

• Harmonic Drive Systems

Inventors

• Shirokoshi Norio

Classifications

• F16H57/08 Primary

  of gearings with members having orbital motion · CPC title

• F16H1/46

  Systems consisting of a plurality of gear trains each with orbital gears, {i.e. systems having three or more central gears} · CPC title

• F16H57/082

  Planet carriers · CPC title

• F16H1/28 Primary

  with gears having orbital motion · CPC title

• F16H57/02

  Gearboxes; Mounting gearing therein · CPC title