Patent ID: 8434387

Claim:
An industrial robot, comprising: a tool mounting portion to which a tool is to be mounted; a tool mounting rotation arm to which the tool mounting portion is to be so mounted as to rotate about a rotation axis; a swing arm for pivotally supporting the tool mounting rotation arm via a pivot shaft; a tool mounting rotation arm driving motor provided in the swing arm and adapted to generate a rotational drive force of the tool mounting rotation arm; a tool mounting rotation arm driving transmission mechanism for transmitting the rotational drive force of the tool mounting rotation arm driving motor to the pivot shaft; a tool mounting rotation arm driving reduction mechanism provided in the swing arm, engaged with the outer periphery of the pivot shaft and adapted to pivot the tool mounting rotation arm while decelerating the rotational drive force of the pivot shaft; a tool mounting portion driving motor provided in the swing arm and adapted to generate a rotational drive force of the tool mounting portion; an intermediate power transmission shaft which is arranged on the inner periphery of the pivot shaft and operates on the same axis; a tool mounting portion driving first transmission mechanism for transmitting the rotational drive force supplied from the tool mounting portion driving motor to the intermediate power transmission shaft; an output power transmission shaft provided in the tool mounting rotation arm in parallel with the intermediate power transmission shaft; a tool mounting portion driving second transmission mechanism provided in the tool mounting rotation arm and adapted to transmit the rotation of the intermediate power transmission shaft to the output power transmission shaft; an intermediate output gear which is mounted on the output power transmission shaft and operates on the same axis; a tool mounting portion driving reduction unit provided in the tool mounting rotation arm, engaged with the intermediate output gear and adapted to decelerate the rotation of the intermediate output gear; and an output gear provided in the tool mounting portion driving reduction unit in the tool mounting rotation arm, engaged with an outer gear of the tool mounting portion and adapted to transmit the rotation decelerated by the tool mounting portion driving reduction unit to the tool mounting portion.