Abstract: This invention relates to an articulated robot comprising at least two control arms (4), (7), and two speed reducers provided at articulated portions of the two control arms (4), (7) on the same axis in opposed relation to each other. The two speed reducers comprises first and second harmonic drive speed reducers which include a common circular spline (60) fixedly secured to the articulated portion of one of the control arms (4), (7), and a bracket (40), (50) mounted on one end of the common circular spline (60) for angular movement relative to the common circular spline (60) and connected to the articulated portion of the control arm (4), (7). The number of component parts can be reduced, the assembling operation can be facilitated, a stable high accuracy can be maintained, and an inexpensive articulated robot can be obtained.

Abstract: The robot articulation device includes a first arm pivoted on a support stand for rotation about a first axis and a second arm is pivotally mounted on the free end of the first arm for rotational movement about a second axis. The first and second axes may be vertically or horizontally disposed. Opposed recessed are located in the first and second arms concentric with the second axis and a sleeve secured to one of the arms extends into the recess in the other arm. A projection is secured to the other arm and extends into the sleeve and bearings are disposed between the projection and the sleeve and the sleeve and the recess, respectively. A gear reduction unit is located in the other recess and is provided with an input shaft which may be driven from a drive motor mounted on the support stand.

Abstract: An industrial robot is disclosed in which inertia is reduced and backlash substantially eliminated by mounting motors for the first and second movable arms on a stationary stand, and transmitting torque to the second arm by means of timing belts. A harmonic gear mechanism arranged at the juncture of the first and second arms reduces the speed of the output timing pulley. The belt arrangement requires no lubrication and is lighter and much quieter in operation than previous torque transmitting arrangements.