Internally Meshing Planetary Gear Apparatus and Joint Apparatus for Robot

A joint device for a robot, comprising:

• an internal-meshing planetary gear device comprising:
• a bearing member, provided with an outer ring, and an inner ring arranged on an inner side of the outer ring and supported to be rotatable relative to the outer ring with a rotation axis as a center;
• an internally toothed gear, provided with internal teeth and fixed to the outer ring;
• a planetary gear, provided with external teeth partially meshing with the internal teeth;
• and
• a plurality of inner pins, configured to revolve in a plurality of inner pin holes formed in the planetary gear and configured to rotate relative to the internally toothed gear, in a state where the plurality of inner pins are inserted into the plurality of inner pin holes respectively,
• an inner peripheral surface of each of the plurality of inner pin holes configured to press against each corresponding inner pin of the plurality of inner pins to apply a pre-pressure to each corresponding inner pin of the plurality of inner pins, when the plurality of inner pins do not rotate relative to the internally toothed gear,
• the internal-meshing planetary gear device further comprising a support structure configured to support each of the plurality of inner pins to counteract moment generated from each of the plurality of inner pins due to the pre-pressure;
• a first member fixed to the outer ring;
• and
• a second member fixed to the inner ring.