Abstract: A tool-rest driving device comprising a drive motor having its output shaft, a first rotatable shaft axially aligned with the motor output shaft and driven to rotate by the motor output shaft, a tool rest having at least one rotational tool, a reduction gear arranged between the first rotatable shaft and the tool rest for reducing the number of rotations of the motor output shaft, the tool rest being rotated at the reduced number of rotations, and a second rotatable shaft arranged coaxially of the motor output shaft for driving the rotational tool of the tool rest. A center axis of the rotational shaft, a center axis of the reduction gear and an axis of rotation of the tool rest are arranged on the same axis.

Abstract: A robot arm drive apparatus of an industrial robot comprising: an electric motor having a drive shaft; a first robot member having the electric motor mounted thereon; a second robot member rotatably supported on the first robot member; and reduction gears for reducing rotation of the electric motor and then transmitting to the second robot member; the reduction gears comprising a planetary reduction gear and furthermore an additional reduction gear which is purposely provided so that the number of rotations of the electric motor, at which the resonance of a drive system comprising the electric motor, the second robot member and the reduction gear means occurs, is shifted from a predetermined operational region of the electric motor.

Abstract: In articulation drive apparatus of an industrial robot which includes a first member (5) of the robot, a second member (12) of the robot freely rotatably supported on the first member and a reduction gear apparatus for reducing rotation of an electric motor integrally connected to the first member and transmitting the reduced rotation to the second member, the improvement wherein the reduction gear apparatus (3) comprises a primary reduction gear (20) for reducing the number of rotations of the electric motor (1) and a secondary planetary reduction gear (21) for further reducing the number of rotations of output of the primary reduction gear (20). Resonance phenomenon of the drive system is prevented by modifying the construction of the reduction gear apparatus used in the robot drive system, and furthermore, by using bar-shaped members (60), the robot is made small and light in weight and stands a relatively larger torsional rigidity.

Abstract: A robot arm drive apparatus of an industrial robot comprising: an electric motor having a drive shaft; a first robot member having the electric motor mounted thereon; a second robot member rotatably supported on the first robot member; and reduction gear means for reducing rotation of the electric motor and then transmitting to the second robot member. The reduction gear means has a primary reduction gear for reducing the rotation of the electric motor and a secondary, planetary reduction gear for further reducing rotation of output of the primary reduction gear. The primary reduction gear has a reduction ratio such that the maximum number of rotations of the electric motor is reduced less than the characteristic torsion frequency of the drive system.

Abstract: An improved hydraulic control circuit is disclosed for use in crawler type vehicles and the like in which relief valves as used in conventional circuits are eliminated. The resulting hydraulic circuit is not apt to be damaged by surge pressures and high pressures in the return passages, are simple in their design and more convenient to fabricate.