Patent ID: 8353798
Filing Date: 2013-01-15
Classification: B25J,F16H

Abstract:
1. A gear transmission configured to be connected to a lower arm of a multi joint robot and to rotate a wrist of the multi-joint robot about a rotational axis of the lower arm, the gear transmission comprising: an internal gear member having an internal gear formed on its inner circumference; a carrier positioned coaxially with a central axis of the internal gear and being rotatably supported on the internal gear member; an external gear meshing with the internal gear and being supported on the carrier in an eccentrically rotatable manner; a first shaft extending through the carrier along the central axis of the internal gear and being rotatably borne on the carrier so as to be rotatable independent of the internal gear, the external gear and the carrier, the first shaft being configured to transmit a drive torque inputted by a first motor at one axial end of the first shaft to its other axial end, which is configured to be coupled to an input shaft of another gear transmission; a second shaft extending through an interior of the first shaft coaxially with the first shaft and rotatably supported on the first shaft via bearings; a first gear affixed at a robot base-side end of the first shaft, the first gear being configured to be mechanically coupled to the first motor, and a second gear affixed at a robot base-side end of the second shaft, the second gear being configured to be mechanically coupled to a second motor, wherein the first shaft is detachably connected to a first drive shaft at a robot tip-side end of the first shaft, the second shaft is detachably connected to a second drive shaft at a robot tip-side end of the second shaft, and the first and second drive shafts are configured to transmit respective torques to respective joints disposed at a tip-side of the lower arm.