Robot and method for manufacturing robot
Object To provide a robot and a method for manufacturing the robot with which downsizing of an arm is possible. Solution to Problem A robot 1 includes a lower arm portion 9 , an elbow portion 11 rotatably coupled to the lower arm portion 9 , a motor 23 housed in the lower arm portion 9 and including a motor shaft 31 rotating around a motor axial center AxM, a first gear 33 coupled to the motor shaft 31 and rotating around the motor axial center AxM, a second gear 37 rotating, in conjunction with the first gear 33 , around a gear axial center AxG intersecting the motor axial center AxM, and a decelerator 27 configured to decelerate rotation of an input shaft 47 and transmit the decelerated rotation to an output shaft 51 , the decelerator including the input shaft 47 configured to rotate, in conjunction with the second gear 37 , around a decelerator axial center AxR coinciding with the gear axial center AxG, and the output shaft 51 coupled to the elbow portion 11.
1 . A robot comprising:
a first arm;
a second arm rotatably coupled to the first arm;
a motor housed in the first arm and including a rotation shaft configured to rotate around a first axial center;
a first gear coupled to the rotation shaft and configured to rotate around the first axial center;
a second gear configured to rotate, in conjunction with the first gear, around a second axial center intersecting the first axial center;
a housing rotatably supporting the second gear and coupled to the motor;
a tubular member configured to attach to and detach from the housing; and
a decelerator configured to decelerate rotation of an input shaft and transmit the decelerated rotation to an output shaft, wherein
the decelerator includes:
the input shaft configured to rotate around the second axial center in conjunction with the second gear; and
the output shaft coupled to the second arm,
the second gear includes a first hollow portion extending along the second axial center,
the input shaft includes a second hollow portion extending along the second axial center,
the first arm includes an opening and a cover configured to close the opening,
in a state where the second gear and the input shaft are coupled to each other:
the first hollow portion and the second hollow portion communicate with each other along the second axial center,
the tubular member is disposed inside the first hollow portion and the second hollow portion, and
the housing and an entirety of the motor are exposed through the opening on a side opposite to the decelerator along the second axial center, and
the tubular member includes a flange portion at one end of the tubular member that is nearer to the opening than the other end of the tubular member.
2 . The robot according to claim 1 ,
wherein
the housing is configured to attach to and detach from the first arm.
3 . The robot according to claim 2 , wherein
one of the second gear and the input shaft includes a shaft portion including a first uneven portion on an outer periphery of the shaft portion and extending along the second axial center,
the other of the second gear and the input shaft includes a hole portion into which the shaft portion is inserted,
the hole portion includes a second uneven portion on an inner periphery of the hole portion, and
the second uneven portion extends along the second axial center and is fitted with the first uneven portion.
4 . The robot according to claim 3 , wherein
the shaft portion includes a first space at the first uneven portion,
in the state where the second gear and the input shaft are coupled, the second uneven portion moves within the first space toward a base end side of the shaft portion along of the second axial center,
the hole portion includes a second space at the second uneven portion, and
in the state where the second gear and the input shaft are being coupled, the first uneven portion moves within the second space toward a distal end side of the shaft portion along the second axial center.
5 . The robot according to claim 1 , wherein a dimension of the opening along the first axial center is greater than a sum of a dimension of the housing along the first axial center and a dimension of the motor, along the first axial center.
6 . A method for manufacturing a robot including a first arm and a second arm rotatably coupled to the first arm, the method comprising:
coupling a second gear to an input shaft of a decelerator to cause the second gear and the input shaft to rotate around a second axial center, wherein
the second gear is configured to rotate in conjunction with a first gear configured to rotate around a first axial center of a motor housed in the first arm,
the first gear is coupled to a rotation shaft configured to rotate around the first axial center,
the decelerator is configured to decelerate rotation of the input shaft and transmit the decelerated rotation to an output shaft, and includes:
the input shaft configured to rotate, in conjunction with the second gear, around the second axial center intersecting the first axial center; and
the output shaft coupled to the second arm; and
inserting a tubular member into a first hollow portion and a second hollow portion, wherein
tubular member is configured to attach to and detach from a housing that rotatably supports the second gear and is coupled to the motor,
the second gear includes the first hollow portion extending along the second axial center,
the input shaft includes the second hollow portion extending along the second axial center,
the first arm includes an opening and a cover configured to close the opening,
in a state where the second gear and the input shaft are coupled to each other:
the first hollow portion and the second hollow portion communicate with each other along the second axial center, and
the housing and an entirety of the motor are exposed through the opening on a side opposite to the decelerator along the second axial center, and
the tubular member includes a flange portion at one end of the tubular member that is nearer to the opening than the other end of the tubular member.