Abstract: An industrial robot is disclosed which is movable about six revolute axes, and which is modular in nature, to permit it to be configured to efficiently operate in a number of different applications. The robot includes a support stand defining a first primary axis, a waist which is rotatable about the first axis and which defines a second primary axis disposed perpendicular to the first axis, an inner arm fixed to the waist for rotation about the second axis, an outer arm fixed to the inner arm for relative rotation about a third primary axis, and a hand assembly mounted at the end of the outer arm. In addition, the outer arm includes a simplified drive arrangement composed of three concentric tubular members and respective drive motors, for moving the hand assembly of the robot about three additional axes of movement.

Abstract: An industrial robot is disclosed which includes three primary drive units defining three separately controlled axes of movement, and an outer arm assembly having three additional axes of movement. The three primary drive units are interconnected so that a first drive unit defines a vertical axis of movement, and the second and third drive units define horizontal axes of movement which are coaxial. Also, the three primary drive units each include an electrical stepping motor which has its rotor and stator coaxially disposed about the axis of movement, with the rotor and stator being respectively fixed to the output components, to thereby eliminate the need for any torque converting drive train between the motor and output components.

Abstract: An industrial robot is disclosed, which utilizes three like drive units for controlling movement about the three primary axes of rotation. Each drive unit comprises a pair of electrical stepping motors, which act through a differential gear train to control movement about the associated axis. Preferably, the number of teeth in the output drive gear of one motor differs from the number of teeth in the output drive gear of the other motor, whereby both motors may be operated at the same rotational speed to permit accurately controllable relative movement at a relatively slow speed, and one motor may be de-energized to achieve high speed operation.