US 12,275,139 B2
Wrist device and robot
Takeshi Shibata, Kobe (JP); and Hitoshi Kudo, Kobe (JP)
Assigned to KAWASAKI JUKOGYO KABUSHIKI KAISHA, Kobe (JP)
Appl. No. 17/923,611
Filed by Kawasaki Jukogyo Kabushiki Kaisha, Kobe (JP)
PCT Filed May 7, 2021, PCT No. PCT/JP2021/017516
§ 371(c)(1), (2) Date Nov. 7, 2022,
PCT Pub. No. WO2021/230153, PCT Pub. Date Nov. 18, 2021.
Claims priority of application No. 2020-083805 (JP), filed on May 12, 2020.
Prior Publication US 2023/0182326 A1, Jun. 15, 2023
Int. Cl. B25J 17/02 (2006.01); B25J 9/10 (2006.01)
CPC B25J 17/0283 (2013.01) [B25J 9/102 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A wrist device, comprising:
a first element coupled to an arm configured to be rotatable about a first rotation axis;
a second element coupled to the first element configured to be rotatable about a second rotation axis which is perpendicular to the first rotation axis;
a first driver in the arm and configured to rotationally drive the first element;
a second driver in the arm and configured to rotationally drive the second element;
a first transmission in the arm and configured to transmit a driving force of the first driver to the first element; and
a second transmission in the arm and in the first element, the second transmission configured to transmit a driving force of the second driver to the second element,
wherein:
the second transmission includes a first driving gear which rotates about the first rotation axis and a first driven gear, the first driving gear being rotatably supported by the arm, the first driven gear being rotatably supported by the first element and configured to mesh with the first driving gear,
the second transmission reduces a rotation speed of a corresponding driving force in a component group including the first driving gear and one or more components downstream of the first driving gear,
the first driving gear is smaller than the first driven gear,
a first rotational motion of the first driving gear about the first rotation axis causes a second rotational motion of the first driven gear, a magnitude of the second rotational motion being less than a magnitude of the first rotational motion,
the second transmission includes a second driving gear and a second driven gear, the second driving gear being rotatably supported by the first element and configured to be rotated by rotation of the first driven gear, the second driven gear being in the second element and configured to mesh with the second driving gear, and
a set of the first driving gear and the first driven gear and a set of the second driving gear and the second driven gear reduce the rotation speed of the corresponding driving force, and
the first driven gear and the second driving gear are coaxially and non-rotatably coupled to each other.